U.S. patent application number 11/348323 was filed with the patent office on 2006-08-10 for substrate processing apparatus, control method adopted in substrate processing apparatus and program.
This patent application is currently assigned to TOKYO ELECTRON LIMITED. Invention is credited to Shinichiro Hayasaka, Seiichi Kaise, Toshiyuki Kobayashi, Hiroshi Nakamura.
Application Number | 20060176928 11/348323 |
Document ID | / |
Family ID | 36779875 |
Filed Date | 2006-08-10 |
United States Patent
Application |
20060176928 |
Kind Code |
A1 |
Nakamura; Hiroshi ; et
al. |
August 10, 2006 |
Substrate processing apparatus, control method adopted in substrate
processing apparatus and program
Abstract
A substrate processing apparatus according to the present
invention comprises a plurality of processing chambers, discharge
systems each provided in conjunction with one of the processing
chambers and a common discharge system connected with the discharge
systems of at least two processing chambers among the discharge
systems provided in conjunction with the individual processing
chambers. The common discharge allows a switch-over between a
scrubbing common discharge system that discharges discharge gas
from each processing chamber after scrubbing the discharge gas at a
scrubbing means and a non-scrubbing common discharge system that
directly discharges the discharge gas from the discharge system of
the processing chamber without scrubbing at the scrubbing means. In
this substrate processing apparatus, switch-over control is
executed to select either the scrubbing common discharge system of
the non-scrubbing common discharge system in correspondence to the
type of processing executed in the processing chamber.
Inventors: |
Nakamura; Hiroshi;
(Yamanashi, JP) ; Kobayashi; Toshiyuki; (Miyagi,
JP) ; Hayasaka; Shinichiro; (Miyagi, JP) ;
Kaise; Seiichi; (Yamanashi, JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
TOKYO ELECTRON LIMITED
Minato-ku
JP
|
Family ID: |
36779875 |
Appl. No.: |
11/348323 |
Filed: |
February 7, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60702990 |
Jul 28, 2005 |
|
|
|
60655425 |
Feb 24, 2005 |
|
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Current U.S.
Class: |
373/60 |
Current CPC
Class: |
H01L 21/6719 20130101;
H01L 21/67017 20130101 |
Class at
Publication: |
373/060 |
International
Class: |
H05B 7/18 20060101
H05B007/18 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 8, 2005 |
JP |
2005-032340 |
Jul 15, 2005 |
JP |
2005-206376 |
Claims
1. A substrate processing apparatus, comprising: a plurality of
processing chambers in each of which a specific type of processing
is executed by using a gas supplied thereto; discharge systems each
provided in conjunction with one of said processing chambers; and a
common discharge system connected with said discharge systems of at
least two processing chambers among said discharge systems provided
in conjunction with said processing chambers, wherein: said common
discharge system allows a switch-over between a scrubbing common
discharge system that discharges discharge gas from said discharge
system of each processing chamber after scrubbing the discharge gas
at a scrubbing means and a non-scrubbing common discharge system
that directly discharges the discharge gas from said discharge
systems of said processing chambers without scrubbing at said
scrubbing means; and said substrate processing apparatus further
includes a control means for executing switch-over control to
select either said scrubbing common discharge system or said
non-scrubbing common discharge system in correspondence to the type
of processing executed at said processing chamber.
2. A substrate processing apparatus according to claim 1, wherein:
when concurrent processing is executed in said plurality of
processing chambers connected to said common discharge system, said
control means executes a specific type of exclusivity control so
that while either first processing constituted with processing
executed by switching said common discharge system to said
non-scrubbing common discharge system or second processing
constituted with processing executed by switching said common
discharge system to said scrubbing common discharge system is in
progress in one of said plurality of processing chambers, the other
type of processing is not executed in any of the remaining
processing chambers among said plurality of processing chambers
3. A substrate processing apparatus according to claim 2, further
comprising: an access right reservation information storage means
for storing reservation information with regard to an access right
of a given processing chamber to said common discharge system,
wherein: when either said first processing or said second
processing is to be executed in a processing chamber among said
plurality of processing chambers connected to said common discharge
system, said exclusivity control for said processing chambers is
executed by; making a decision as to whether or not one type of
processing, i.e., either said first processing or said second
processing, is currently being executed in another processing
chamber among said plurality of processing chambers connected with
said common discharge system; and executing the other type of
processing if said one type of processing is judged not to be in
progress in the other processing chamber; or executing reservation
processing through which said other type of processing is set in a
processing wait state, access right reservation information for
said other type of processing with regard to an access right to
said common discharge system is stored into said access right
reservation information storage means and then said other type of
processing is executed based upon said reservation information in
said access right reservation information storage means, if said
one type of processing is judged to be currently in progress in
said other processing chamber.
4. A substrate processing apparatus according to claim 3, wherein:
said reservation processing enables execution of said other type of
processing in said processing chamber having been set in the
processing wait state, after said one type of processing in said
other processing chamber is completed.
5. A substrate processing apparatus according to claim 4, wherein:
if a plurality of sets of reservation information indicating access
right reservations for said common discharge system corresponding
to a plurality of processing chambers have been stored in said
access right reservation information storage means, said
reservation processing enables execution of said other type of
processing in the order in which said plurality of sets of
reservation information have been stored.
6. A substrate processing apparatus according to claim 1, wherein:
said first processing at least includes processing through which a
subject processing chamber is discharged to a pressure level equal
to or greater than a predetermined level without requiring
discharge gas scrubbing and said second processing at least
includes processing that generates discharge gas requiring
scrubbing.
7. A substrate processing apparatus according to claim 6, wherein:
said first processing is roughing vacuum processing executed in
said subject processing chamber or processing that includes said
roughing vacuum processing said second processing is processing gas
supply processing that necessitates discharge of said processing
chamber or processing that includes said processing gas supply
processing.
8. A substrate processing apparatus according to claim 7, wherein:
said first processing is automatic inspection processing or
maintenance processing executed in said processing chamber, which
includes said roughing vacuum processing in said processing
chamber.
9. A substrate processing apparatus according to claim 7, wherein:
said second processing is automatic inspection processing or
maintenance processing executed in said processing chamber, which
includes said processing gas supply processing in said processing
chamber.
10. A substrate processing apparatus according to claim 6, wherein:
both said first processing and said second processing are said
roughing vacuum processing executed in said processing chamber, or
both said first processing and said second processing are
processing that include said roughing vacuum processing.
11. A substrate processing apparatus according to claim 1, wherein:
a gas supply system through which gas is supplied into each of said
processing chambers includes a processing gas supply system for
supplying a processing gas and an inert gas supply system for
supplying an inert gas; and the inert gas supply system includes a
first supply system through which the inert gas can be supplied at
a predetermined flow rate and a second supply system through which
the inert gas can be supplied at a flow rate higher than the flow
rate set for said first supply system.
12. A substrate processing apparatus according to claim 11,
wherein: when executing particle reduction processing in said
processing chamber, the inert gas is supplied at least via said
second supply system.
13. A substrate processing apparatus according to claim 12,
wherein: said particle reduction processing is executed in said
processing chamber by first supplying the inert gas at least via
said second supply system over a predetermined length of time and
then supplying the inert gas via said first supply system only.
14. A control method to be adopted in a substrate processing
apparatus, comprising: a plurality of processing chambers in each
of which a specific type of processing is executed by using a gas
supplied thereto; discharge systems each provided in conjunction
with one of said processing chambers; and a common discharge system
connected with said discharge systems of at least two processing
chambers among said discharge systems provided in conjunction with
said processing chambers, which allows a switch-over between a
scrubbing common discharge system that discharges discharge gas
from said discharge system of each processing chamber after
scrubbing the discharge gas at a scrubbing means and a
non-scrubbing common discharge system that directly discharges the
discharge gas from said discharge systems of said processing
chamber without scrubbing at said scrubbing means, wherein:
switch-over control is executed to select either said scrubbing
common discharge system or said non-scrubbing common discharge
system in correspondence to the type of processing executed at said
processing chamber.
15. A control method to be adopted in a substrate processing
apparatus according to claim 14, wherein: a specific type of
exclusivity control is executed when concurrent processing is
executed in said plurality of processing chambers connected to said
common discharge system, so that while either first processing
constituted with processing executed by switching said common
discharge system to said non-scrubbing common discharge system or
second processing constituted with processing executed by switching
said common discharge system to said scrubbing common discharge
system is in progress in one of said plurality of processing
chambers, the other type of processing is not executed in any of
the remaining processing chambers among said plurality of
processing chambers.
16. A control method to be adopted in a substrate processing
apparatus according to claim 15, wherein: said substrate processing
apparatus further includes an access right reservation information
storage means for storing reservation information with regard to an
access right of a given processing chamber to said common discharge
system, and said exclusivity control executed in each of said
processing chambers includes steps for: making a decision as to
whether or not one type of processing, i.e., either said first
processing or said second processing, is currently being executed
in another processing chamber among said plurality of processing
chambers connected with said common discharge system when either
said first processing or said second processing is to be executed
in a processing chamber among said plurality of processing chambers
connected to said common discharge system; executing the other type
of processing if said one type of processing is judged not to be in
progress in said other processing chamber, or executing reservation
processing through which said other type of processing is set in a
processing wait state, access right reservation information for
said other type of processing with regard to an access right to
said common discharge system is stored into said access right
reservation information storage and then said other type of
processing is executed based upon said reservation information in
said access right reservation information storage means if said one
type of processing is judged to be in progress in said other
processing chamber.
17. A control method to be adopted in a substrate processing
apparatus according to claim 16, wherein: said reservation
processing enables execution of said other type of processing in
said processing chamber having been set in the processing wait
state, after said one type of processing in said other processing
chamber is completed.
18. A control method to be adopted in a substrate processing
apparatus according to claim 17, wherein: if a plurality of sets of
reservation information indicating access right reservations for
said common discharge system corresponding to a plurality of
processing chambers have been stored in said access right
reservation information storage means, said reservation processing
enables execution of said other type of processing in the order in
which said plurality of sets of reservation information have been
stored.
19. A control method to be adopted in a substrate processing
apparatus according to claim 14, wherein: said first processing at
least includes processing through which a subject processing
chamber is discharged to a pressure level equal to or greater than
a predetermined level without requiring discharge gas scrubbing and
said second processing at least includes processing that generates
discharge gas requiring scrubbing.
20. A control method to be adopted in a substrate processing
apparatus according to claim 19, wherein: said first processing is
roughing vacuum processing executed in said subject processing
chamber or processing that includes said roughing vacuum processing
said second processing is processing gas supply processing that
necessitates discharge of said processing chamber or processing
that includes said processing gas supply processing.
21. A control method to be adopted in a substrate processing
apparatus according to claim 20, wherein: said first processing is
automatic inspection processing or maintenance processing executed
in said processing chamber, which includes said roughing vacuum
processing in said processing chamber.
22. A control method to be adopted in a substrate processing
apparatus according to claim 20, wherein: said second processing is
automatic inspection processing or maintenance processing executed
in said processing chamber, which includes said processing gas
supply processing in said processing chamber.
23. A control method to be adopted in a substrate processing
apparatus according to claim 19, wherein: both said first
processing and said second processing are said roughing vacuum
processing executed in said processing chamber, or both said first
processing and said second processing are processing that include
said roughing vacuum processing.
24. A control method to be adopted in a substrate processing
apparatus according to claim 14, wherein: a gas supply system
through which gas is supplied into each of said processing chambers
includes a processing gas supply system for supplying a processing
gas and an inert gas supply system for supplying an inert gas; and
the inert gas supply system includes a first supply system through
which the inert gas can be supplied at a predetermined flow rate
and a second supply system through which the inert gas can be
supplied at a flow rate higher than the flow rate set for said
first supply system.
25. A control method to be adopted in a substrate processing
apparatus according to claim 24, wherein: when executing particle
reduction processing in said processing chamber, the inert gas is
supplied at least via said second supply system.
26. A control method to be adopted in a substrate processing
apparatus according to claim 25, wherein: said particle reduction
processing is executed in said processing chamber by first
supplying the inert gas at least via said second supply system over
a predetermined length of time and then supplying the inert gas via
said first supply system only.
27. A program that enables control of a substrate processing
apparatus, comprising: a plurality of processing chambers in each
of which a specific type of processing is executed by using gas
supplied thereto; discharge systems each provided in conjunction
with one of said processing chambers; and a common discharge system
connected with said discharge systems of at least two processing
chambers among said discharge systems provided in conjunction with
said processing chambers, which allows a switch-over between a
scrubbing common discharge system that discharges discharge gas
from said discharge system of each processing chamber after
scrubbing the discharge gas at a scrubbing means and a
non-scrubbing common discharge system that directly discharges the
discharge gas from said discharge system of said processing chamber
without scrubbing at said scrubbing means, wherein: said program
enables a computer to execute switch-over control between said
scrubbing common discharge system and said non-scrubbing common
discharge system in correspondence to the type of processing
executed at said processing chamber.
28. A program according to claim 27, wherein: if processing is
concurrently executed at said plurality of processing chambers
connected with said common discharge system, a specific type of
exclusivity control is executed so that while either first
processing constituted with processing executed by switching said
common discharge system to said non-scrubbing common discharge
system or second processing constituted with processing executed by
switching said common discharge system to said scrubbing common
discharge system is in progress in one of said plurality of
processing chambers, the other type of processing is not executed
in any of the remaining processing chambers among said plurality of
processing chambers
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This document claims priority to Japanese Patent Application
No. 2005-032340 filed Feb. 8, 2005, Japanese Patent Application No.
2005-206376 filed Jul. 15, 2005, U.S. Provisional Application No.
60/655,425 filed Feb. 24, 2005, and U.S. Provisional Application
No. 60/702,990 filed Jul. 28, 2005, the entire contents of which
are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a substrate processing
apparatus that includes a scrubbing device for scrubbing discharge
gas that is discharged while a substrate such as a semiconductor
wafer or a liquid crystal substrate is processed, a control method
to be adopted in a substrate processing apparatus and a
program.
BACKGROUND OF THE INVENTION
[0003] Substrate processing apparatuses include plasma processing
apparatuses that execute processing such as film formation and
etching by using specific types of gases on substrates such as
semiconductor wafers (hereafter may be referred to simply as
"wafers") placed inside processing chambers or clean the inside of
the processing chambers with a specific type of gas.
[0004] The discharge gas discharged from a processing chamber of
such a substrate processing apparatus may be toxic or may contain a
substance that places a heavy burden on the environment. Thus, it
would be detrimental to the environment to directly release the
discharge gas into the atmosphere. This issue is addressed in some
substrate processing apparatuses by releasing the discharge gas
from a processing chamber via a scrubbing device that scrubs
(eliminates noxious elements in) the discharge gas through a heat
treatment or the like.
[0005] For instance, the substrate processing apparatus shown in
FIG. 24 includes scrubbing devices 20A and 20B respectively
provided in conjunction with processing chambers 10A and 10B. In
this substrate processing apparatus, the scrubbing devices 20A and
20B respectively connected with discharge systems 12A and 12B for
the individual processing chambers 10A and 10B scrub the discharge
gas from the processing chambers 10A and 10B. This type of
substrate processing apparatus, which requires as many scrubbing
devices as processing chambers, is bound to take up a large
installation space and its manufacturing costs are bound to be
high.
[0006] These problems are addressed by adopting a structure such as
that shown in FIG. 25, which includes a common discharge system 31
connected with discharge systems 12A and 12B of the individual
processing chambers 10A and 10B, with the common discharge system
31 connected with a scrubbing device 30 to serve both the
processing chambers 10A and 10B so as to scrub the discharge gas
from the processing chambers 10A and 10B through a single scrubbing
device 30 (see, for instance, Japanese Laid Open Patent Publication
No. H11-8200 and Japanese Laid Open Patent Publication No.
2004-95643).
SUMMARY OF THE INVENTION
[0007] The processing executed in the individual processing
chambers may include discharge processing executed at a relatively
high pressure, such as roughing vacuum processing executed prior to
wafer processing in the processing chamber to reduce the pressure
in the processing chamber from atmospheric pressure (one
atmosphere) to a predetermined level. Since such roughing vacuum
processing is executed before the processing gas is drawn into the
processing chambers, it does not necessitate discharge gas
scrubbing.
[0008] However, the discharge gas from each processing chamber in
the structure shown in FIG. 24 or 25 is invariably scrubbed via the
scrubbing device and is then discharged, regardless of the type of
processing executed in the processing chamber. This means that the
gas discharged through the roughing vacuum processing or the like,
which is discharged under high pressure conditions and does not
require scrubbing, too, has to first undergo scrubbing via the
scrubbing device before it is released. As a result, the onus
placed on the scrubbing device increases, which leads to a reduced
service life of the scrubbing device.
[0009] In addition, the significant increase in the size of
substrates to undergo processing, such as wafers and liquid crystal
panels seen in recent years has necessitated an increase in the
size of processing chambers. This, in turn, has resulted in a great
increase in the quantities of discharge gas discharged from the
processing chambers, and ultimately a greater onus on scrubbing
devices.
[0010] Furthermore, since the discharge gas is scrubbed through,
for instance, a heat treatment at a scrubbing device, the level of
energy required for the discharge processing rises as the number of
scrubbing devices included in the processing system increases. As a
result, the energy efficiency at the plant where such substrate
processing apparatuses are installed is lowered and the level of
energy consumption at the entire plant rises. Accordingly, from the
viewpoint of improving the overall energy efficiency and the
overall cost efficiency at the plant, it is crucial to scrub
discharge gas while economizing on energy consumption.
[0011] This leads to the conclusion that it is more desirable to
use fewer scrubbing devices, i.e., it is more desirable to use a
common scrubbing device to serve multiple processing chambers, as
shown in FIG. 25, than to provide a scrubbing device in
correspondence to each of the processing chambers, as shown in FIG.
24. However, in the structure shown in FIG. 25, all the discharge
gas from the plurality of processing chambers is gathered into the
common scrubbing device and thus, if concurrent processing is
executed at the individual processing chambers, the onus on the
scrubbing device may increase depending upon the types of
processing executed in the processing chambers.
[0012] Accordingly, an object of the present invention, having been
completed by addressing the problems of the related art discussed
above, is to provide a substrate processing apparatus, a control
method to be adopted in a substrate processing apparatus and a
program, which reduce the onus on a scrubbing means for scrubbing
the discharge gas and also reduce the energy and the cost required
for the discharge gas scrubbing.
[0013] The object described above is achieved in an aspect of the
present invention by providing a substrate processing apparatus
comprising a plurality of processing chambers in each of which a
specific type of processing is executed by using gas supplied
thereto, discharge systems each provided in conjunction with one of
the processing chambers and a common discharge system connected
with the discharge systems of at least two processing chambers
among the discharge systems provided in conjunction with the
individual processing chambers. The common discharge system in this
substrate processing apparatus allows a switch-over between a
scrubbing common discharge system that discharges discharge gas
from the discharge system of each processing chambers after
scrubbing the discharge gas at a scrubbing means and a
non-scrubbing common discharge system that directly discharges the
discharge gas from the discharge systems of the processing chamber
without scrubbing at the scrubbing means, and the substrate
processing apparatus further includes a control means that executes
switch-over control to select either the scrubbing common discharge
system or the non-scrubbing common discharge system in
correspondence to the type of processing executed at the processing
chamber.
[0014] The object described above is achieved in another aspect of
the present invention by providing a control method to be adopted
in a substrate processing apparatus comprising a plurality of
processing chambers in each of which a specific type of processing
is executed by using a gas supplied thereto, discharge systems each
provided in correspondence to one of the processing chambers and a
common discharge system connected with the discharge systems of at
least two processing chambers among the discharge systems provided
in conjunction with the individual processing chambers, with the
common discharge system allowing a switch-over between a scrubbing
common discharge system that discharges discharge gas from the
discharge system of each processing chamber after scrubbing the
discharge gas at a scrubbing means and a non-scrubbing common
discharge system that directly discharges the discharge gas from
the discharge system of the processing chamber without scrubbing at
the scrubbing means. In this control method, switch-over control is
executed to select either the scrubbing common discharge system or
the non-scrubbing common discharge system in correspondence to the
type of processing executed at the processing chamber.
[0015] By adopting the apparatus or the control method according to
the present invention described above, switch-over control is
executed to select the scrubbing common discharge system or the
non-scrubbing common discharge system in correspondence to the
types of processing executed at the individual processing chambers
and thus, the non-scrubbing common discharge system can be selected
in correspondence to, for instance, roughing vacuum processing
during which a gas that does not need to be scrubbed is discharged
under high pressure conditions so as to release the gas without
scrubbing at the scrubbing means. As a result, the onus on the
scrubbing means for scrubbing discharge gas is reduced and the
energy and the cost required for the discharge gas scrubbing are
also reduced.
[0016] In the apparatus or the control method described above, a
specific type of exclusivity control may be executed when
concurrent processing is executed in the plurality of processing
chambers connected to the common discharge system so that while
either first processing constituted with processing executed by
switching the common discharge system to the non-scrubbing common
discharge system (e.g., roughing vacuum processing executed to
reduce the pressure from atmospheric pressure, which does not
require discharge gas scrubbing) or second processing constituted
with processing executed by switching the common discharge system
to the scrubbing common discharge system (e.g., processing one a
substrate, which requires discharge gas scrubbing) is in progress
in one of the plurality of processing chambers, the other type of
processing is not executed in any remaining processing chamber
among the plurality of processing chambers. By taking these
measures, it is ensured that the first processing and the second
processing are not simultaneously executed in different processing
chambers. As a result, failure to scrub discharge gas requiring
scrubbing can be reliably prevented while, at the same time,
reducing the onus on the scrubbing means.
[0017] The apparatus described above may include, or the control
method described above may employ, an access right reservation
information storage means for storing reservation information with
regard to an access right of a given processing chamber to the
common discharge system. When either the first processing or the
second processing is to be executed in a processing chamber among
the plurality of processing chambers connected to the common
discharge system, the exclusivity control for the individual
processing chambers may be executed in conjunction with the access
right reservation information storage means by making a decision as
to whether or not one type of processing, i.e., either the first
processing or the second processing, is currently being executed in
any of the other processing chambers among the plurality of
processing chambers connected with the common discharge system,
executing the other type of processing if the one type of
processing is judged not to be in progress in the other processing
chambers, and executing reservation processing if the one type of
processing is judged to be in progress in any of the other
processing chambers. Through the reservation processing, the other
type of processing is set in a processing wait state, access right
reservation information for the one type of processing with regard
to an access right to the common discharge system is stored into
the access right reservation information storage means and then the
other type of processing is subsequently based upon the reservation
information in the access right reservation information storage
means. The reservation processing enables execution of the other
type of processing in the processing chamber having been set in the
processing wait state, after the one type of processing in the
other processing chamber is completed. Through such reservation
processing, processing can be automatically executed in the
processing chamber having been set in the processing wait
state.
[0018] If a plurality of sets of reservation information indicating
access right reservations for the common discharge system
corresponding to a plurality of processing chambers have been
stored in the access right reservation information storage means,
the reservation processing may enable execution of the other type
of processing in the order in which the individual sets of
reservation information have been stored. In this case, if
reservations for the common discharge system are made in
correspondence to a plurality of processing chambers, the
processing in the individual chambers can be executed in the order
in which the reservations are registered.
[0019] In the apparatus or the control method described above, the
first processing may be, for instance, processing that includes at
least processing through which the subject processing chamber is
discharged to a pressure level equal to or greater than a
predetermined level without requiring discharge gas scrubbing and
the second processing may be processing that includes at least
processing that generates discharge gas requiring scrubbing. When
the first processing and the second processing defined as such are
executed under the control described above, the discharge gas
discharged under high pressure conditions is not released via the
scrubbing means and the discharge gas that needs to be scrubbed is
never released without first being scrubbed at the scrubbing means.
The onus on the scrubbing means in such an apparatus or in such a
control method is thereby reduced
[0020] The first processing executed in the apparatus or through
the control method may be, for instance, roughing vacuum processing
in the subject processing chamber or processing that includes the
roughing vacuum processing (e.g., automatic inspection processing
or maintenance processing for the processing chamber during which
roughing vacuum processing is executed as part thereof). The second
processing may be, for instance, processing gas supply processing
that necessitates discharge of the processing chamber or processing
that includes the processing gas supply processing (e.g., automatic
inspection processing or maintenance processing during which
processing gas supply processing is executed as part thereof).
Since automatic inspection processing or maintenance processing may
include roughing vacuum processing or processing gas supply
processing, the execution of exclusivity control on the first
processing and the second processing in conjunction with such
automatic inspection processing or maintenance processing will
reduce the onus on the scrubbing means while reliably preventing
any discharge gas requiring scrubbing from being released without
first going through the process of scrubbing.
[0021] In the apparatus or the control method described above, the
first processing and the second processing may both be the roughing
vacuum processing at the processing chamber or processing that
includes the roughing vacuum processing. In this case, simultaneous
execution of, for instance, roughing vacuum processing at different
processing chambers can be prevented and thus, the discharge gas
from roughing vacuum processing requiring scrubbing is not directly
released without first being scrubbed. At the same time, the
reverse flow of the discharge gas due to the difference between the
pressure levels at the individual processing chambers attributable
to the difference in the timing with which the roughing vacuum
processing starts at the individual processing chambers can be
reliably prevented.
[0022] In the apparatus or the control method described above, a
gas supply system through which gas is supplied into the processing
chambers may include a processing gas supply system for supplying a
processing gas and an inert gas supply system for supplying an
inert gas. The inert gas supply system may, in turn, include a
first supply system through which the inert gas can be supplied at
a predetermined flow rate and a second supply system through which
the inert gas can be supplied at a flow rate higher than the flow
rate set for the first supply system. When inert gas supply
processing is executed at a low flow rate via the first supply
system, the subject processing chamber can be discharged via the
scrubbing means by switching to the scrubbing common discharge
system, whereas when inert gas supply processing is executed at a
high flow rate via the second supply system, the processing chamber
can be discharged by switching to the non-scrubbing common
discharge system so as to allow the discharge gas to be released
without being scrubbed at the scrubbing means. Consequently, the
onus on the discharge device can be reduced.
[0023] When executing particle reduction processing in the
processing chamber in the apparatus or the control method, the
inert gas may be supplied at least via the second supply system.
During particle reduction processing, roughing vacuum processing,
through which the processing chamber is discharged initially at a
high pressure level without requiring the discharge gas to be
scrubbed, may be executed and the discharge gas resulting from such
processing can be released by switching to the non-scrubbing common
discharge system without scrubbing the discharge gas at the
scrubbing means. Thus, the onus on the scrubbing means for
discharge gas scrubbing can be reduced, and the energy and the cost
required for discharge gas scrubbing can also be reduced. In
addition, regardless of whether the inert gas is continuously
supplied or briefly supplied for the particle reduction processing,
gas shock waves generated under specific conditions by supplying
the inert gas at a high flow rate via the second supply system can
be used to clean the interior of the processing chamber.
[0024] The processing chamber may be cleaned by initially supplying
the inert gas at least via the second supply system over a
predetermined length of time and then supplying the inert gas
entirely via the first supply system. A gas shock wave, generated
under specific conditions by briefly supplying the inert gas into
the processing chamber at a high flow rate over a predetermined
length of time, can then be used to clean the interior of the
processing chamber. In addition, even if the inert gas is
discharged through the scrubbing common discharge system via the
scrubbing means, the inert gas will be discharged at a high flow
rate only briefly, and thus, the onus on the scrubbing device is
not increased.
[0025] The object described above is also achieved in yet another
aspect of the present invention by providing a program to be used
to control a substrate processing apparatus comprising a plurality
of processing chambers in each of which a specific type of
processing is executed by using a gas supplied thereto, discharge
systems each provided in correspondence to one of the processing
chambers and a common discharge system connected with the discharge
systems of at least two processing chambers among the discharge
systems provided in conjunction with the individual processing
chambers, common discharge system allowing a switch-over between a
scrubbing common discharge system that discharges discharge gas
from the discharge system of each processing chambers after
scrubbing the discharge gas at a scrubbing means and a
non-scrubbing common discharge system that directly discharges the
discharge gas from the discharge system of the processing chamber
without scrubbing the discharge gas at the scrubbing means. The
program enables a computer to execute switch-over control between
the scrubbing common discharge system and the non-scrubbing common
discharge system in correspondence to the type of processing
executed at each processing chamber. By executing this program, the
onus on the scrubbing means can be reduced.
[0026] If processing is concurrently executed at the plurality of
processing chambers connected with the common discharge system, the
program may enable execution of a specific type of exclusivity
control so that while either first processing constituted with
processing executed by switching the common discharge system to the
non-scrubbing common discharge system or second processing
constituted with processing executed by switching the common
discharge system to the scrubbing common discharge system is in
progress in one of the plurality of processing chambers, the other
type of processing is not executed in any of the remaining
processing chambers among the plurality of processing chambers. By
executing this program, it is ensured that the first processing and
the second processing are not simultaneously executed in different
processing chambers. As a result, failure to scrub discharge gas
requiring scrubbing can be reliably prevented while, at the same
time, reducing the onus on the scrubbing means.
[0027] According to the present invention, the onus on the
scrubbing means for scrubbing discharge gas can be reduced, and the
energy and the cost required for the discharge gas scrubbing can
both be reduced. In addition, when processing is to be executed
concurrently at a plurality of processing chambers, the switch-over
between the non-scrubbing common discharge system and the scrubbing
common discharge system is not allowed to occur while the one type
of processing is in progress. As a result, any discharge gas
requiring scrubbing is always discharged as scrubbed gas without
fail, while reducing the onus placed on the scrubbing means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a sectional view showing the structure adopted in
a substrate processing apparatus achieved in an embodiment of the
present invention;
[0029] FIG. 2 is a block diagram presenting a piping structure
example that may be adopted in the individual processing chambers
and an example of a structure that may be adopted in the scrubbing
device at the substrate processing apparatus shown in FIG. 1;
[0030] FIG. 3 illustrates a flow of discharge gas that may be
observed when the discharge gas from a single processing chamber
engaging the scrubbing device is discharged via the non-scrubbing
common discharge system;
[0031] FIG. 4 illustrates a flow of discharge gas that may be
observed when the discharge gas from a single processing chamber
engaging the scrubbing device is discharged via the scrubbing
common discharge system;
[0032] FIG. 5 illustrates a flow of discharge gas that may be
observed when processing is concurrently executed at two processing
chambers;
[0033] FIG. 6 illustrates a flow of discharge gas that may be
observed when processing is concurrently executed at two processing
chambers;
[0034] FIG. 7 illustrates a flow of discharge gas that may be
observed when processing is concurrently executed at two processing
chambers;
[0035] FIG. 8 illustrates a flow of discharge gas that may be
observed when processing is concurrently executed at two processing
chambers;
[0036] FIG. 9 is a block diagram presenting an example of a
structure that may be adopted in the control unit in the
embodiment;
[0037] FIG. 10 presents a specific example of a data table holding
the processing status management information used in the
embodiment;
[0038] FIG. 11 presents a specific example of a data table holding
the scrubbing device access right reservation information used in
the embodiment;
[0039] FIG. 12 presents a flowchart of a specific example of
control under which the first processing is executed in the
embodiment;
[0040] FIG. 13 presents a flowchart of a specific example of
control under which the second processing is executed in the
embodiment;
[0041] FIG. 14 is a block diagram presenting a specific example of
a structure that may be adopted in the gas supply systems in FIG.
2;
[0042] FIG. 15 illustrates a flow of discharge gas that may be
observed when wafer processing is executed at a processing chamber
adopting the piping structure in FIG. 14;
[0043] FIG. 16 illustrates a flow of discharge gas that may be
observed when particle reduction processing is executed at a
processing chamber adopting the piping structure in FIG. 14;
[0044] FIG. 17 is a block diagram presenting another specific
example of a structure that may be adopted in the gas supply system
in FIG. 2;
[0045] FIG. 18 presents a flowchart of a specific example of
control under which the particle reduction processing is executed
at a processing chamber adopting the piping structure in FIG.
17;
[0046] FIG. 19 presents a flowchart of a specific example of the
first NPPC in FIG. 17;
[0047] FIG. 20 presents a flowchart of a specific example of the
second NPPC in FIG. 17;
[0048] FIG. 21 illustrates a flow of discharge gas that may be
observed when the first NPPC is executed at a processing chamber
adopting the piping structure in FIG. 17;
[0049] FIG. 22 illustrates a flow of discharge gas that may be
observed when the second NPPC is executed at a processing chamber
adopting the piping structure in FIG. 17;
[0050] FIG. 23 illustrates a flow of discharge gas that may be
observed when the second NPPC is executed at a processing chamber
adopting the piping structure in FIG. 17;
[0051] FIG. 24 is a block diagram presenting an example of a
substrate processing apparatus in the related art, which includes
scrubbing devices; and
[0052] FIG. 25 is a block diagram presenting another example of a
substrate processing apparatus in the related art, which includes a
scrubbing device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0053] The following is a detailed explanation of preferred
embodiments of the present invention, given in reference to the
attached drawings. It is to be noted that in the specification and
the drawings, the same reference numerals are assigned to
components having substantially identical functions and structural
features to preclude the necessity for a repeated explanation
thereof.
[0054] (Structural Example Adopted in Substrate Processing
Apparatus)
[0055] First, the substrate processing apparatus achieved in an
embodiment of the present invention is explained in reference to
drawings. FIG. 1 schematically shows the structure adopted in the
substrate processing apparatus in an embodiment of the present
invention. The substrate processing apparatus 100 comprises a
processing unit 110 where various types of processing such as film
formation and etching are executed on substrates which may be, for
instance, semiconductor wafers (hereafter may be simply referred to
as "wafers") W and a transfer unit 120 that transfers the wafers W
to/from the processing unit 110.
[0056] First, an example of a structure that may be adopted in the
transfer unit 120 is explained. As shown in FIG. 1, the transfer
unit 120 includes a transfer chamber 130 through which wafers are
transferred between substrate storage containers such as cassette
containers 132 (132A through 132C) to be detailed later and the
processing unit 110. The transfer chamber 130 is formed as a box
with a substantially polygonal section. On one side of the transfer
chamber 130 along the longer side of its substantially polygonal
section, a plurality of cassette stages 131 (131A through 131C) are
disposed side-by-side. The cassette containers 132A through 132C
representing an example of substrate storage containers can be
placed on the cassette stages 131A through 131C respectively.
[0057] The cassette containers 132 (132A through 132C) each has a
capacity for holding up to, for instance, 25 wafers W stacked with
uniform pitches. The cassette containers adopt a sealed structure
with their inner space filled with, for instance, an N.sub.2 gas
atmosphere. The wafers W can be transferred between the transfer
chamber 130 and the cassette containers via gate valves. It is to
be noted that the numbers of the cassette stages 131 and the
cassette containers 132 are not limited to those shown in FIG.
1.
[0058] An orienter (pre-alignment stage) 136 to function as a
positioning device is disposed at an end of the transfer chamber
130. This orienter 136 aligns a wafer W by detecting an orientation
flat, a notch or the like in the wafer W.
[0059] Inside the transfer chamber 130, a transfer unit-side
transfer mechanism (transfer chamber internal transfer mechanism)
170 that transfers a wafer W along the longer side of the transfer
chamber (along the direction indicated by the arrow in FIG. 1) via,
for instance, a linear drive mechanism is disposed. The transfer
unit-side transfer mechanism 170 is driven based upon a control
signal provided by a control unit 400. It is to be noted that the
transfer unit-side transfer mechanism 170 may be a double-arm
mechanism with two picks such as that shown in FIG. 1, or it may be
a single-arm mechanism with a single pick.
[0060] Next, an example of a structure that may be adopted in the
processing unit 110 is explained. The processing unit 110 in, for
instance, a cluster tool-type substrate processing apparatus may
include a plurality of processing chambers 200 (first through
fourth processing chambers 200A through 200D) where specific types
of processing such as film formation (e.g., plasma CVD processing)
and etching (e.g., plasma etching) are executed on wafers W and
load-lock chambers 160M and 160N, all connected around a common
transfer chamber 150 assuming a Polygonal shape (e.g., a hexagonal
shape) as shown in FIG. 1 with a high level of airtightness.
[0061] Gas supply systems 210A through 210D (not shown in FIG. 1)
through which specific types of gases to be used as a processing
gas and a purge gas can be supplied into the individual processing
chambers 200A through 200D and discharge systems 220A through 220D
through which the processing chambers 200A through 200D can be
discharged are respectively connected to the processing chambers
200A through 200D. It is to be noted that examples of structures
that may be adopted in the gas supply systems and the discharge
systems are to be described in detailed later.
[0062] The processing chambers 200A through 200D may adopt the
internal structure described below. Namely, an upper electrode and
a lower electrode are disposed so as to face opposite each other
inside each of the processing chambers 200A through 200D. The gas
supply system mentioned above is connected to the upper electrode.
The lower electrode also functions as a stage on which a wafer W is
placed. High frequency power sources that apply high frequency
power at specific levels are connected to the upper electrode and
the lower electrode.
[0063] As a wafer W, for instance, is transferred into each of the
processing chambers 200A through 200D and placed on the lower
electrode, the processing chamber is set in a state of vacuum with
a predetermined pressure level through discharge processing
executed via the corresponding discharge system. The high frequency
power is applied to the upper electrode and the lower electrode and
the processing gas supplied from the gas supply system is evenly
directed toward the wafer W via the upper electrode. The processing
gas drawn in via the upper electrode is then raised to plasma with
which the surface of the wafer W is, for instance, etched.
[0064] Wafers W are processed in the individual processing chambers
200A through 200D based upon wafer processing information such as
process recipes indicating specific processing steps and the like,
which is stored in advance at a storage means or the like in, for
instance, the control unit 400. The contents of the wafer
processing information vary depending upon the types of the wafer
processing and the conditions under which the wafer processing is
to be executed. It is to be noted that the number of processing
chambers 200 may be different from that shown in FIG. 1.
[0065] The common transfer chamber 150 has a function of
transferring wafers W between the individual processing chambers
200A through 200D described above and/or between the processing
chambers 200A through 200D and the first and second load-lock
chambers 160M and 160N. The common transfer chamber 150 assumes a
polygonal shape (e.g., a hexagonal shape). The processing chambers
200 (200A through 200D), which are disposed around the common
transfer chamber, are each connected with the common transfer
chamber via a gate valve and the front ends of the first and second
load-lock chambers 160M and 160N are each connected with the common
transfer chamber via a gate valve (a vacuum pressure-side gate
valve). The base ends of the first and second load-lock chambers
160M and 160N are connected to the other side surface of the
transfer chamber 130 each via a gate valve (an atmospheric
pressure-side gate valve).
[0066] The first and second load-lock chambers 160M and 160N have a
function of temporarily holding wafers W and passing them on to
subsequent stages after pressure adjustment. Inside each of the
first and second load-lock chambers 160M and 160N, a transfer stage
on which a wafer can be placed is disposed.
[0067] At the processing unit 110 structured as described above,
the passages between the common transfer chamber 150 and the
individual processing chambers 200A through 200D and the passages
between the common transfer chamber 150 and the individual
load-lock chambers 160M and 160N can be opened/closed while
assuring a high level of airtightness, thereby achieving a
cluster-tool structure that allows communication with the common
transfer chamber 150 as necessary. In addition, the passages
between the transfer chamber 130 and the first and second load-lock
chambers 160M and 160N, too, can be opened/closed while assuring
airtightness.
[0068] Inside the common transfer chamber 150, a processing
unit-side transfer mechanism (common transfer chamber internal
transfer mechanism) 180 constituted with articulated arms capable
of flexing, moving up/down and rotating, for instance, is disposed.
This processing unit-side transfer mechanism is used to transfer
wafers W from the load-lock chambers 160M and 160N to the
individual processing chambers 200A through 200D and vice versa.
The processing unit-side transfer mechanism 180 is driven based
upon a control signal provided by the control unit 400. It is to be
noted that the processing unit-side transfer mechanism 180 may be a
double-arm mechanism with two picks such as that shown in FIG. 1,
or it may be a single-arm mechanism with a single pick.
[0069] The substrate processing apparatus 100 includes the control
unit 400 that controls the overall operations of the substrate
processing apparatus including control of the transfer unit-side
transfer mechanism 170, the processing unit-side transfer mechanism
180, the various gate valves and the orienter 136. An example of a
structure that may be adopted in such a control unit 400 is
explained later.
[0070] The substrate processing apparatus 100 also includes a
common scrubbing device 300 that scrubs (eliminates noxious
elements in) gases discharged from the various processing chambers
200A through 200D. The scrubbing device 300 is connected to a
common discharge system 310 connected with the discharge systems
220A through 220D respectively provided in conjunction with the
processing chambers 200A through 200D. The common discharge system
310 is connected via the scrubbing device 300 to a discharge system
at, for instance, a plant where the substrate processing apparatus
100 is installed.
[0071] As the substrate processing apparatus 100 structured as
described above is engaged in operation, processing on wafers W
starts. For instance, a wafer W taken out of one of the cassette
containers 132A through 132C by the transfer unit-side transfer
mechanism 170 is then carried over to the orienter 136. After
undergoing alignment at the orienter 136, the wafer W is carried
out of the orienter 136 and is moved into either the load-lock
chamber 160M or the load-lock chamber 160N. If a processed wafer W
having undergone all the required processing is present in the
load-lock chamber 160M or 160N at this time, the unprocessed wafer
W is carried into the load-lock chamber after carrying out the
processed wafer W.
[0072] The wafer having been carried into the load-lock chamber
160M or 160N is transferred out of the load-lock chamber 160M or
160N by the processing unit-side transfer mechanism 180, and is
transferred into the processing chamber 200 where it is to undergo
the specific type of processing. Once the processing is completed
in the processing chamber 200, the processed wafer is transferred
out of the processing chamber 200 by the processing unit-side
transfer mechanism 180. If the wafer W needs to undergo continuous
processing at a plurality of processing chambers 200, the wafer is
carried into another processing chamber 200 to undergo the next
phase of processing.
[0073] Ultimately, the processed wafer having undergone all the
required processing is carried back into the load-lock chamber 160M
or 160N. The processed wafer W having been moved back into the
load-lock chamber 160M or 160N is then taken back into the initial
cassette container among the cassette containers 132A through 132C
by the transfer unit-side transfer mechanism 170.
[0074] The discharge gases discharged via the discharge systems
220A through 220D of the processing chambers 200A through 200D
while the substrate processing apparatus 100 is engaged in
operation are then directed from the common discharge system 310
to, for instance, the plant exhaust system via the scrubbing device
300.
[0075] Now, an example of a piping structure that may be adopted in
the individual processing chambers 200A through 200D and an example
of a structure that may be adopted in the scrubbing device 300 are
explained in reference to a drawing. FIG. 2 is a block diagram
showing an example of a piping structure that may be adopted in the
individual processing chambers 200A through 200D and an example of
a structure that may be adopted in the scrubbing device 300. Since
the piping structures at the processing chambers 200A through 200D
are identical, an explanation is given below on a processing
chamber 200 representing the individual processing chambers 200A
through 200D. This means that the processing chamber 200 may be any
of the processing chambers 200A through 200D.
[0076] (Example of Piping Structure in Processing Chamber)
[0077] First, the piping structure (which includes the gas supply
system and the discharge system) adopted at the processing chamber
200 is explained. As shown in FIG. 2, a pressure sensor 280 that
detects a pressure inside the processing chamber 200, a gas supply
system 210 through which a specific type of gas to be used a
processing gas or a purge gas can be supplied into the processing
chamber 200 and a discharge system 220 through which the processing
chamber 200 can be discharged are disposed in conjunction with the
processing chamber 200.
[0078] The gas supply system 210 may be constituted by, for
instance, connecting a gas supply source 212 to the processing
chamber 200 via a gas supply valve 214. The gas drawn into the
processing chamber 200 from the gas supply source 212 may be a
processing gas requiring scrubbing upon discharge from the
processing chamber, such as a PFC gas (CF.sub.4, C.sub.2F.sub.6 or
the like) which hastens the process of global warming, or NF.sub.3,
SF.sub.6, NH.sub.3, NO.sub.x, hydrogen halide or a heavy-metal
alkoxide complex containing hazardous components. Or the gas drawn
into the processing chamber 200 may be an inert gas used as a purge
gas or a pressure adjusting gas. The term "inert gas" is used in
the description to broadly refer to a gas that does not induce a
chemical change readily and, such an inert gas may be N.sub.2 gas,
as well as any of the rare gas elements such as Ar and He. It is to
be noted that the gas supply system 210 may adopt a structure other
than that shown in FIG. 2. For instance, a flow regulating means
such as a mass flow controller or a check valve may be disposed
downstream of the gas supply valve.
[0079] The discharge system 220 may be constituted by, for
instance, connecting in parallel a main discharge system 230 and an
auxiliary discharge system 240 to the processing chamber 200. The
main discharge system 230 and the auxiliary discharge system 240
join each other on the discharge side and are together connected to
an auxiliary pump 250. A main pump 260 is connected to the main
discharge system 230, whereas a switch-over valve (switching valve,
auxiliary valve) 270 used to switch between discharge through the
main discharge system 230 and discharge through the auxiliary
discharge system 240 is connected to the auxiliary discharge system
240. It is to be noted that the main pump 260 connected to the main
discharge system 230 is connected with the processing chamber 200
via a pressure adjusting valve (APC) (not shown).
[0080] The auxiliary pump 250 may be a dry pump with which roughing
vacuum processing is executed to evacuate the processing chamber
200 to a state of vacuum achieving a specific pressure. The main
pump 260 may be, for instance, a turbo-pump with which main
discharge processing is executed to further evacuate the processing
chamber 200 until a desired vacuum is achieved. The discharge side
of the auxiliary pump 250 in the discharge system 220 is connected
to the scrubbing device 300 via the common discharge system 310. It
is to be noted that as long as roughing vacuum processing, at
least, can be executed with the discharge system 220, the discharge
system 220 may adopt a structure other than that shown in FIG.
2.
[0081] The pressure sensor 280 is constituted with, for instance, a
diaphragm gauge (e.g., a capacitance manometer). An output from the
pressure sensor 280 is provided to the control unit 400 of the
substrate processing apparatus 100. In addition, the gas supply
valve 214 in the gas supply system 210 and the switch-over valve
270 in the discharge system 220 are controlled based upon control
signals provided by the control unit 400.
[0082] (Examples of Operations at Gas Supply System and Discharge
System)
[0083] Before processing a wafer W in the processing chamber 200
structured as described above, discharge processing is first
executed with the gate valve at the processing chamber 200 kept in
a closed state so as to reduce the pressure inside the processing
chamber 200 to a predetermined level. During the discharge
processing, the pressure inside the processing chamber is first
lowered to a specific level through the roughing vacuum processing
and then the pressure at the specific level may be further lowered
to a level having been set to achieve a high level of vacuum
through main discharge processing.
[0084] More specifically, the roughing vacuum processing is first
executed by opening the switch-over valve 270 so as to switch the
discharge system 220 to the auxiliary discharge system 240 and
driving the auxiliary pump 250. Then, once the pressure inside the
processing chamber detected by the pressure sensor 280 is lowered
to the specific level, the switch-over valve 270 is closed to
switch the discharge system 220 to the main discharge system 230
and the main discharge processing is executed by driving the main
pump 260 until the pressure detected by the pressure sensor 280 is
lowered to the preset level.
[0085] Once the main discharge processing is completed, the gate
valve is opened and the wafer W is carried into the processing
chamber 200. After the wafer W is placed on the stage, the gate
valve is closed and the operation shifts to processing the wafer W.
At this time, the processing gas from the gas supply source 212 is
drawn into the processing chamber 200 by opening the gas supply
valve 214 while the switch-over valve 270 is in a closed state and
the main discharge system 230 is selected at the discharge system
220, and thus, the processing of the wafer W starts. Namely, the
wafer W is processed over a predetermined length of time while the
pressure inside the processing chamber 200 is sustained at the
predetermined level by monitoring the pressure detected by the
pressure sensor 280.
[0086] Once the wafer W is processed, the gas supply valve 214 is
closed, carryover discharge of the processing chamber 200 is
executed via the main discharge system 230 and the processed wafer
W is carried out of the processing chamber 200. The processing of
the particular wafer W thus ends. Subsequently, a next wafer W is
carried into the processing chamber 200. Namely, wafers W are
sequentially processed one at a time through the procedure
described above. The discharge gas discharged through the discharge
system 220 of the processing chamber 200 as wafers W are processed
as described above is directed to, for instance, the factory
discharge system from the common discharge system 310 via the
scrubbing device 300.
[0087] (Example of Structure that May be Adopted in Scrubbing
Device)
[0088] Next, an example of a structure that may be adopted in the
scrubbing device is explained. The scrubbing device 300 is
connected with the common discharge system 310. More specifically,
the common discharge system 310 branches into a scrubbing common
discharge system 320, through which the discharge gas from the
processing chamber 200 is first scrubbed in the scrubbing device
300 and is then discharged and a non-scrubbing common discharge
system 330, through which the discharge gas from the processing
chamber 200 is directly discharged without undergoing
scrubbing.
[0089] A scrubbing means 340 for scrubbing the discharge gas from
the common discharge system 310 is connected to the scrubbing
common discharge system 320, whereas a switch-over valve (switching
valve) 350 that effects a switch-over between discharge through the
scrubbing common discharge system 320 and discharge through the
non-scrubbing common discharge system 330 is connected to the
non-scrubbing common discharge system 330. The discharge sides of
the scrubbing common discharge system 320 and the non-scrubbing
common discharge system 330 join each other and are then together
connected to the plant exhaust system.
[0090] It is to be noted that the scrubbing means 340 may be
constituted with, for instance, a scrubbing reactor tank where the
discharge gas passing through the scrubbing common discharge system
320 is scrubbed through a heat treatment. It is to be noted that
the scrubbing means may scrub the discharge gas through any of
various types of processing other than a heat treatment. The
switch-over valve 350 of the scrubbing device is controlled based
upon a control signal provided via the control unit 400. The
control unit 400 executes switch-over control for the switch-over
valve 350 of the scrubbing device 300 in correspondence to the type
of processing executed in the processing chamber 200.
[0091] (Example of Operations Executed at Scrubbing Device)
[0092] Next, an example of operations that may be executed at the
scrubbing device structured as described above is explained in
reference to drawings. First, operations that may be executed when
the discharge gas from a single processing chamber is discharged
via the scrubbing device 300 are explained. In the example
explained below, the scrubbing device 300 is engaged in operation
to discharge gas from the processing chamber 200A among the
processing chambers 200A through 200D. FIGS. 3 and 4 illustrate
flows of the discharge gas (indicated by the bold arrows) that may
be observed when the gas in the processing chamber 200A alone is
discharged via the scrubbing device 300.
[0093] As explained earlier, the switch-over between discharge via
the scrubbing common discharge system 320 and discharge via the
non-scrubbing common discharge system 330 is effected depending
upon the type of processing executed in the processing chamber 200A
via a the switch-over valve 350 at the scrubbing device 300. Thus,
when executing roughing vacuum processing inside the processing
chamber 200A as described above, the switch-over valve 350 of the
scrubbing device 300 is set in an open state to switch to discharge
via the non-scrubbing common discharge system 330, as shown in FIG.
3, to directly discharge the gas without first scrubbing it. When
executing other processing, e.g., when processing a wafer W by
drawing in the processing gas, on the other hand, the switch-over
valve 350 at the scrubbing device 300 is set in a closed state to
switch over to discharge via the scrubbing common discharge system
320, as shown in FIG. 4 to discharge the gas after scrubbing
it.
[0094] Under normal circumstances, when the roughing vacuum
processing is executed before processing the wafer W, no processing
gas is drawn into the processing chamber yet and thus, no discharge
gas containing a harmful substance is discharged from the
processing chamber 200A. For this reason, the gas in the processing
chamber 200A may be discharged without it first being scrubbed at
the scrubbing means 340. In addition, a discharge executed to lower
a relatively high pressure, such as roughing vacuum processing
executed to lower the atmospheric pressure will place a significant
onus on the scrubbing device 300 if the gas discharged through the
processing is to the discharged via the scrubbing means 340 of the
scrubbing device 300. However, the gas discharged through such
processing, does not need to be scrubbed at the scrubbing means
340. By directing the discharge gas to be directly discharged
without scrubbing, the onus placed on the scrubbing device 300 can
be reduced to extend the service life of the scrubbing device 300.
Furthermore, since higher efficiency is achieved in the scrubbing
processing, the amount of energy used in the scrubbing processing,
too, is reduced, which allows a scrubbing device with a small
capacity to fully function as a common scrubbing device 300 to
serve the individual processing chambers.
[0095] The types of processing that may be executed in the
processing chamber 200A include, for instance, maintenance
processing executed by an operator and automatic inspection
processing (auto-check processing) automatically executed to
inspect the various units of the substrate processing apparatus 100
to improve the efficiency of regular maintenance work and reduce
the length of time required for regular maintenance work, in
addition to the regular processing executed on wafers W as
described above. The automatic inspection processing (auto-check
processing) includes auto setup processing and self check
processing, and various check items inspected during the processing
include the gas supply system 210A and the discharge system 220A of
the processing chamber 200A. Accordingly, roughing vacuum
processing also needs to be executed in the processing chamber 200,
as described above, for the maintenance processing or the
auto-check processing.
[0096] In particular, when the auto-check processing is underway in
the processing chamber 200A, roughing vacuum processing may be
executed after drawing the processing gas into the processing
chamber through buildup processing during which the pressure inside
the processing chamber is raised to a predetermined level by
drawing in the processing gas from, for instance, the gas supply
system 210A and monitoring the pressure in the processing chamber
with the pressure sensor 280A. Under such circumstances, the
processing gas is discharged through the roughing vacuum
processing, and if the processing gas contains a harmful substance,
it needs to be first scrubbed before it is discharged. In other
words, discharge gas containing a harmful substance is discharged
when a specific type of roughing vacuum processing is executed at
the processing chamber 200A.
[0097] If such roughing vacuum processing is executed with the
switch-over valve 350 at the scrubbing device 300 automatically
switched to discharge via the non-scrubbing common discharge system
330 by interlocking with the switch-over valve 270A, which is
opened to switch to the auxiliary discharge system 240A, a
discharge gas containing harmful substances may be directly
discharged to the plant exhaust system without first being
scrubbed.
[0098] Accordingly, instead of interlocking with the switch-over
valve 270A, the switch-over valve 350 is controlled, as described
below, by the control unit 400 of the substrate processing
apparatus 100. Namely, a decision is made at the control unit 400
as to whether or not the processing to be executed at the
processing chamber 200A is executed initially under high pressure
conditions (e.g., a pressure equal to or higher than a
predetermined level) that does not require, at least, discharge gas
scrubbing. If it is decided that such processing is to be executed
at the processing chamber 200A, the common discharge system 310 is
switched to the non-scrubbing common discharge system 330 by
opening the switch-over valve 350 of the scrubbing device 300, as
shown in FIG. 3, to discharge the gas without first scrubbing it.
If, on the other hand, it is decided that the processing is not
executed initially under high pressure conditions (e.g., a pressure
equal to or higher than a predetermined level), the common
discharge system 310 is switched to the scrubbing common discharge
system 320 by closing the switch-over valve 350 of the scrubbing
device 300, as shown in FIG. 4, to first scrub the gas and then
discharge it.
[0099] The decision as to whether or not the processing is executed
initially under high pressure conditions (e.g., a pressure equal to
or higher than the predetermined level) may be made during this
operation by, for instance, detecting the pressure inside the
processing chamber 200A with a pressure sensor 280A when executing
the processing in the processing chamber 200A, judging that the
processing is initially executed in a high pressure condition if
the detected pressure is equal to or higher than a predetermined
level (e.g., 50 Torr (66.6 hPa)) and judging that the processing is
executed initially under low pressure conditions from the beginning
if the detected pressure is lower than the predetermined level
(e.g., 50 Torr).
[0100] Under this control, the gas discharged through roughing
vacuum processing in the processing chamber 200 at a pressure of,
for instance, one atmosphere, i.e., processing executed initially
under high pressure conditions, which does not require discharge
gas scrubbing, is discharged via the non-scrubbing common discharge
system 330 without undergoing the process of scrubbing.
[0101] In contrast, the gas discharged during maintenance
processing or auto-check processing executed under low pressure
conditions needs to be first scrubbed via the scrubbing common
discharge system 320 and then discharged, even when the gas is
discharged through roughing vacuum processing. In addition, wafer
processing that requires the processing gas to be drawn into the
processing chamber is executed under low pressure conditions and
necessitates scrubbing of the discharge gas. Accordingly, the
discharge gas resulting from such processing, too, is first
scrubbed and then discharged via the scrubbing common discharge
system 320.
[0102] The scrubbing device 300 operating as described above
prevents discharge of any discharge gas containing a harmful
substance to the plant exhaust system with a high level of
reliability. Moreover, even if the gas resulting from the roughing
vacuum processing or the wafer processing executed initially under
low pressure conditions is discharged via the scrubbing means 340,
the onus placed on the scrubbing device 300 on account of such
roughing vacuum processing or wafer processing is not as
significant as the onus placed on the scrubbing device 300 on
account of roughing vacuum processing executed initially under high
pressure conditions.
[0103] Next, an example of operations that may be executed at the
scrubbing device when processing is concurrently executed at a
plurality of processing chambers is explained in reference to
drawings. In the example explained below, processing is
concurrently executed at the processing chambers 200A and 200B
among the processing chambers 200A through 200D. FIGS. 5 through 8
illustrate flows of the discharge gas (indicated by the bold
arrows) that may be observed when processing is executed
concurrently at the processing chambers 200A and 200B.
[0104] As explained earlier, if the processing at the processing
chambers 200A and 200B does not, at least, require discharge gas
scrubbing and is executed initially under high pressure conditions
(e.g., a pressure equal to or higher than a predetermined level),
the common discharge system 310 is switched to the non-scrubbing
common discharge system 330, but otherwise, the common discharge
system 310 is switched to the scrubbing common discharge system
320, according to the present invention.
[0105] When processing is executed concurrently at a plurality of
processing chambers, first processing requiring the common
discharge system 310 to be switched to the non-scrubbing common
discharge system 330 and second processing requiring the common
discharge system 310 to be switched to the scrubbing common
discharge system 320 may be simultaneously executed at different
processing chambers, depending upon the timing with which the
processing at the individual processing chambers is executed. Under
such circumstances, if the first processing starts in a processing
chamber while the second processing is already in progress in
another processing chamber, i.e., while discharge via the scrubbing
common discharge system 320 is underway, the discharge will be
switched to discharge via the non-scrubbing common discharge system
330. As a result, the other processing chamber where the processing
that requires discharge gas scrubbing will be discharged via the
non-scrubbing common discharge system 330 allowing toxic discharge
gas to be discharged to the plant exhaust system.
[0106] For instance, if the first processing, e.g., roughing vacuum
processing for lowering the pressure from one atmosphere is
executed at the processing chamber 200A, as shown in FIG. 6 while
the second processing, e.g., processing of a wafer W executed by
drawing in processing gas from the gas supply system 210B, is
underway at the other processing chamber 200B with the scrubbing
common discharge system 320 engaged in discharge operation, as
shown in FIG. 5, the switch-over valve 350 at the scrubbing device
300 is opened to switch over to discharge via the non-scrubbing
common discharge system 330. As a result, the discharge gas that
needs to be scrubbed, discharged from the processing chamber 200A
is directly discharged to the plant exhaust system via the
non-scrubbing common discharge system 330 without first undergoing
the process of scrubbing, as shown in FIG. 6.
[0107] If, on the other hand, second processing, e.g., wafer
processing executed by drawing in the processing gas from, for
instance, the gas supply system 210B, is executed at the processing
chamber 200A, as shown in FIG. 8 while the first processing, e.g.,
roughing vacuum processing executed to lower the pressure from one
atmosphere, is underway at the processing chamber 200B by engaging
the non-scrubbing common discharge system 330 in discharge
operation as shown in FIG. 7, the switch-over valve 350 at the
scrubbing device 300 is closed to switch over to discharge via the
scrubbing common discharge system 320. In this case, while the
problem of discharge gas that needs to be scrubbed, discharged from
the processing chamber 200A, being directly discharged to the plant
exhaust system via the non-scrubbing common discharge system 330
without first being scrubbed does not occur, the gas from the
processing chamber 200B where the processing is executed initially
under high pressure conditions is discharged unnecessarily via the
scrubbing means 340 through the scrubbing common discharge system
320, thereby increasing the onus placed on the scrubbing device
300.
[0108] According to the present invention, this problem is
addressed by executing a specific type of exclusivity control under
which processing is concurrently executed at a plurality of
processing chambers by ensuring that when either the first
processing or the second processing is currently in progress in a
given processing chamber, the other processing is not executed in
any of the remaining processing chambers. By executing this
exclusivity control, synchronous execution of processing that does
not require discharge gas scrubbing and processing that does
require discharge gas scrubbing at different processing chambers
are prevented even when processing is executed concurrently at a
plurality of processing chambers. As a result, the onus on the
scrubbing device 300 is reduced and, at the same time, any
discharge gas requiring scrubbing is not allowed to be directly
discharged to the plant exhaust system without first undergoing the
process of scrubbing.
[0109] (Example of Structure Adopted in Control Unit that Executes
Exclusivity Control)
[0110] Next, the control unit that executes the exclusivity control
described above is explained. Since such exclusivity control may be
executed at, for instance, the control unit 400 that controls the
substrate processing apparatus 100, a specific example of a
structure that may be adopted in the control unit 400 is explained
below in reference to FIG. 9.
[0111] The control unit 400 comprises a CPU (central processing
unit) 410 constituting the control unit main body, a ROM (read only
memory) 420 having stored therein program data (e.g., program data
used to execute processing on wafers W, various types of check
processing executed in the substrate processing apparatus as
described later, scrubbing device access right processing, particle
reduction processing and the like) based upon which the CPU 410
controls the various units and the like, a RAM (random access
memory) 430 that includes a memory area used by the CPU 410 when it
executes various types of data processing, a time measuring means
440 constituted with a counter or the like used to measure lengths
of time, a display means 450 constituted with a liquid crystal
display or the like at which an operation screen or a selection
screen is brought up on display, an input/output means 460 that
allows an operator to input/output various types of data, a warning
means 470 constituted with, for instance, an alarm such as a
buzzer, various controllers 480 used to control the various units
constituting the substrate processing apparatus 100 and a storage
means 490 constituted with, for instance, a memory, as shown in
FIG. 9.
[0112] The CPU 410, the ROM 420, the RAM 430, the time measuring
means 440, the display means 450, the input/output means 460, the
warning means 470, the various controllers 480 and the storage
means 490 are electrically connected via a bus line such as a
control bus, a system bus or a data bus.
[0113] The various controllers 480 include a controller that
controls the various units constituting the individual processing
chambers 200A through 200D and a valve controller that controls the
gas supply valve 214 at the gas supply system 210, the switch-over
valve 270 at the discharge system 220 and the switch-over valve 350
at the scrubbing device, as well as the controller used to control
the individual transfer mechanisms 170 and 180 and orienter 136. It
is to be noted that the various units constituting the processing
chambers 200A through 200D may instead be controlled by control
units each provided in conjunction with one of the processing
chambers 200A through 200D. In such a case, the control unit 400
should be connected with the individual control units serving the
respective processing chambers 200A through 200D so as to control
the substrate processing apparatus 100 by exchanging data and
signals.
[0114] At the storage means 490, processing status management
information 492 on the processing status indicating whether or not
the first processing or the second processing is in progress at
each of the processing chambers 200A through 200D, scrubbing device
access right reservation information (common discharge system
access right reservation information) 494 reserving an access right
to the scrubbing device 300 for execution of the first processing
or the second processing and the like are stored.
[0115] A specific example of the processing status management
information 492 is now explained in reference to FIG. 10. As shown
in FIG. 10, the processing status management information 492 is
constituted with a data table that includes entries such as
"processing chamber", "first processing" and "second processing".
The data in the "processing chamber" entry indicate a specific
processing chamber among the processing chambers 200A through 200D
at the substrate processing apparatus 100. The data in the "first
processing" entry and the "second processing" entry respectively
indicate whether or not the first processing and the second
processing are in progress at each subject processing chamber.
[0116] "1" is set (stored) in the "first processing" or the "second
processing" entry as the corresponding processing starts at the
subject processing chamber among the processing chambers 200A
through 200D, and "0" is set (stored) when the processing ends.
Accordingly, "0" set in the "first processing (or second
processing)" entry indicates that the first processing (or second
processing) is not currently executed at the subject processing
chamber, whereas "1" set in the "first processing (or second
processing)" entry indicates that the first processing (or the
second processing) is currently in progress at the subject
processing chamber.
[0117] In the example presented in FIG. 10, "0" is set both in the
"first processing" entry and the "second processing" entry for the
processing chambers 200A, 200C and 200D, indicating that neither
the first processing nor the second processing is currently in
progress at the processing chambers 200A, 200C and 200D. "1" is set
in the "first processing" entry and "0" is set in the "second
processing" entry for the processing chamber 200B, indicating that
while the second processing is not being executed, the first
processing is in progress at the processing chamber 200B.
[0118] Such processing status management information 492 clearly
indicates the processing statuses with regard to the first
processing and the second processing at the individual processing
chambers 200A through 200D, allowing a decision as to whether or
not the first processing and the second processing are currently in
progress at the other processing chambers to be made with ease
based upon the processing status management information 492 when
the first processing or the second processing is to be executed at
a given processing chamber.
[0119] It is to be noted that instead of storing the processing
status management information 492 as a data table such as that
shown in FIG. 10, the processing statuses with regard to the first
processing and the second processing at the processing chambers
200A through 200D may be indicated by flags F.sub.A1 through
F.sub.D1 and flags F.sub.A2 through F.sub.D2' which may be set to
either "0" or "1" as described above.
[0120] Next, a specific example of the scrubbing device access
right reservation information 494 is explained in reference to FIG.
11. The scrubbing device access right reservation information 494
may be constituted with a data table that includes entries such as
"processing chamber" and "processing type", as shown in FIG. 11.
The data in the "processing chamber" entry indicate a specific
processing chamber among the processing chambers 200A through 200D
at the substrate processing apparatus 100. The data in the
"processing type" entry indicate the specific type of processing
(the first processing or the second processing) executed by
reserving an access right to the scrubbing device.
[0121] Reservations for the first processing or the second
processing made in correspondence to the individual processing
chambers 200A through 200D are sequentially stored in the data
table constituting the scrubbing device access right reservation
information 494. Accordingly, the processing (job) having the
reservation is indicated in each line in the data table
constituting the scrubbing device access right reservation
information 494.
[0122] In conjunction with the exclusivity control under which,
when either the first processing or the second processing is in
progress at a given processing chamber, the execution of the other
processing is disallowed at the other chambers, the scrubbing
device access right reservation information 494 is used to reserve
an access right to the scrubbing device 300 (the common discharge
system 310) for subsequent execution of the other processing.
[0123] Such access rights to the scrubbing device 300 are granted
in the order in which reservations are entered in the scrubbing
device access right reservation information 494 on a first come
first serve basis. Accordingly, as a given type of processing
executed at a given processing chamber ends, the other type of
processing (job) at the top of the reservation list in the data
table constituting the scrubbing device access right reservation
information 494 is executed. As the processing is thus executed,
the remaining reservations move up in the reservation list.
[0124] In the example presented in FIG. 11, the reservation for the
first processing to be executed in the processing chamber 200A is
at the top of the reservation list and thus, this processing is
executed first. Once the processing having been reserved first is
executed, the reservation for the first processing to be executed
at the processing chamber 200C, which is second in the reservation
list, moves up to the top of the reservation list.
[0125] A reservation registered in the scrubbing device access
right reservation information 494 can be canceled by the operator
by operating the input/output means 460 at the control unit 400. In
addition, if the processing at a given processing chamber, having
been put on hold through a reservation is interrupted, the
reservation registered in the scrubbing device access right
reservation information 494, too, is canceled. As a reservation is
thus canceled, the remaining reservations sequentially move up in
the reservation list.
[0126] The processing described above may be executed by adopting a
queue table data structure that enables first-in, first-out (FIFO)
control in the data table constituting the scrubbing device access
right reservation information 494.
[0127] (Specific Example of Exclusivity Control of First Processing
and Second Processing)
[0128] Next, a specific example of the exclusivity control of the
first processing and the second processing, executed by the control
unit 400 structured as described above, is explained. In the
example, the first processing is executed by switching the common
discharge system 310 to the non-scrubbing common discharge system
330, and the second processing is executed by switching the common
discharge system 310 to the scrubbing common discharge system
320.
[0129] Examples of the first processing include roughing vacuum
processing executed initially at high-pressure (e.g., a pressure
equal to or higher than 50 Torr), auto-check processing and
maintenance processing during which such roughing vacuum processing
is executed, and cleaning processing through which roughing vacuum
processing is executed, e.g., particle reduction processing (NPPC:
non-plasma particle cleaning) for cleaning the inside of the
processing chamber with a purge gas (or an inert gas) drawn into
the processing chamber. Particle reduction processing may be
executed by alternately evacuating and charging the chamber so as
to the switch between a vacuum and a pressure of one atmosphere
while drawing in a purge gas such as N.sub.2 gas so as to lift and
drive away particles having accumulated in the processing chamber,
or by flaking off and removing particles having accumulated in the
processing chamber with a gas shock wave (a pressure wave
transmitted at a speed exceeding the speed of sound) generated
under specific conditions as a purge gas such as N.sub.2 gas is
drawn into the processing chamber at a high flow rate. Furthermore,
when removing particles with a gas shock wave, the processing
chamber may be discharged while continuously drawing the purge gas
into the processing chamber at a high flow rate (by adopting a
piping structure such as that shown in FIG. 14, for instance) as
described later, or the processing chamber may be evacuated by
drawing the purge gas briefly into the processing chamber at a high
flow rate and subsequently, continuously drawing in the purge gas
at a low flow rate (by adopting a piping structure such as that
shown in FIG. 17).
[0130] Examples of the second processing include processing
executed on a wafer W such as etching or film formation, open
processing for opening the gas supply valve 214 to draw in the
processing gas, which constitutes part of cleaning processing
executed by drawing in the processing gas (e.g., waterless cleaning
processing for cleaning the inside of the processing chamber by
drawing the processing gas into the processing chamber where no
wafer is present), roughing vacuum processing executed initially
under low pressure conditions, and auto-check processing and
maintenance processing during which a processing gas must be drawn
in or roughing vacuum processing must be executed initially in a
low-pressure condition (e.g., a pressure lower than 50 Torr).
[0131] (Specific Example of Control Under which First Processing is
Executed)
[0132] First, a specific example of control under which the first
processing (e.g., roughing vacuum processing initially executed at
high pressure) is executed at a given processing chamber among the
processing chambers 200A through 200D is explained. FIG. 12
presents a flowchart of the specific example of the control under
which the first processing is executed. As shown in FIG. 12, the
execution of the first processing (steps S160 through S190) at a
given processing chamber starts after executing the exclusivity
control (steps S100 through S150).
[0133] During the exclusivity control, a decision is made in step
S100 as to whether or not there is a processing chamber waiting in
standby to execute reserved processing. More specifically, a
decision is made as to whether or not the table constituting the
scrubbing device access right reservation information 494 contains
any reservation for processing (job). This decision is made so as
to confer priority to processing to be executed at another
processing chamber, which has been reserved in the table
constituting the scrubbing device access right reservation
information 494 and awaiting the execution thereof.
[0134] If it is decided in step S100 that there is a processing
chamber waiting in standby for the execution of reserved
processing, i.e., that there is processing (job) for which a
reservation has been made in the table constituting the scrubbing
device access right reservation information 494, the operation
proceeds to step S120 to bring up a display indicating that the
first processing cannot be executed at the display means 450,
before the operation shifts into reservation processing in step
S130 and subsequent steps to be detailed later. As a result,
simultaneous execution of the first processing and the second
processing at different processing chambers is prevented. It is to
be noted that the warning means 490 may be engaged at this time to
warn the operator that the first processing cannot be executed.
[0135] If, on the other hand, it is decided in step S100 that there
is currently no processing chamber waiting for execution of
reserved processing, i.e., that there is no processing (job) the
execution of which has been reserved in the table constituting the
scrubbing device access right reservation information 494, the
operation proceeds to step S110 to make a decision as to whether or
not the second processing is in progress in another processing
chamber. This decision is made so as to prevent simultaneous
execution of the first processing and the second processing at
different processing chambers. More specifically, the decision is
made based upon the processing status management information 492
stored at the storage means 490. For instance, it can be decided
that the second processing is not currently being executed at any
of the processing chambers 200A through 200D based upon the
processing status management information 492 in FIG. 10, which
invariably indicates "0" in the "second processing" entries
corresponding to the individual processing chambers 200A through
200D.
[0136] If it is decided in step S110 that the second processing
(e.g., processing on a wafer W) is not currently in progress at
another processing chamber, the operation shifts into the
processing in step S160 and subsequent steps, thereby starting the
first processing. If, on the other hand, it is decided in step S110
that the second processing is currently in progress at another
processing chamber, the operation proceeds to step S120 to bring up
a display indicating that the first processing cannot the executed
at the display means 450. At this time, the warning means 470 may
be engaged to warn the operator that the first processing cannot be
executed.
[0137] Then, the reservation processing is executed in steps S130
through S150. During the reservation processing, an access right to
the scrubbing device 300 is first reserved in step S130. More
specifically, an access right that will allow the use of the
scrubbing device 300 (the common discharge system 310) is reserved
at the data table constituting the scrubbing device access right
reservation information 494 at the storage means 490.
[0138] Next, a decision is made in step S140 as to whether or not
the second processing at the other processing chamber has ended.
This decision is made based upon the processing status management
information 492 at the storage means 490. As the second processing
having been in progress at the other processing ends, the "second
processing" entry corresponding to the other processing chamber in
the processing status management information 492 is switched from
"1" to "0" and accordingly, the second processing at the other
processing chamber can be judged to have ended when the "second
processing" entry is switched to "0". If it is decided in step S140
that the second processing having been in progress at the other
processing chamber has not ended yet, the operation waits in
standby for the second processing at the other processing chamber
to end.
[0139] If it is decided in step S140 that the second processing
having been in progress at the other processing chamber has ended,
the operation proceeds to step S150 to make a decision as to
whether or not an access right to the scrubbing device 300 has been
obtained. This decision is made in correspondence to the order in
which reservations have been registered in the scrubbing device
access right reservation information 494. The decision as to
whether or not an access right to the scrubbing device 300 has been
obtained is made by judging based upon, for instance, the
processing status management information 492, as to whether or not
the second processing is in progress in another processing chamber.
If the second processing is judged to be not in progress at another
processing chamber, it is decided that an access right to the
scrubbing device 300 has been obtained and, in this case, the
operation shifts to the processing in step S160 and subsequent
steps, thereby starting the first processing.
[0140] If, on the other hand, the second processing is judged to be
in progress in another processing chamber, it is decided that an
access right to the scrubbing device 300 has not been obtained and
the operation waits until an access right to the scrubbing device
300 is obtained. The control follows this flow so as not to execute
the first processing if the second processing is underway at yet
another processing chamber while the second processing is in
progress in a given processing chamber, since the exclusivity
control does not apply to concurrent executions of the second
processing at different processing chambers. Through this
reservation processing, the processing in a processing chamber in a
processing wait state can be automatically started.
[0141] Next, an explanation is given on how the first processing is
started. When starting the first processing, first processing start
information is recorded in step S160. More specifically, "1" is set
(stored) in the "first processing" entry in the data table
constituting the processing status management information 492.
[0142] Next, the first processing is executed in step S170. The
first processing (e.g., roughing vacuum processing executed
initially under high pressure conditions) is executed by opening
the switch-over valve 350 of the scrubbing device 300 and thus
switching the common discharge system 310 to the non-scrubbing
common discharge system 330. The gas discharged from the processing
chamber as a result is directly discharged to, for instance, the
plant exhaust system without being scrubbing at the scrubbing means
340.
[0143] Then, a decision is made in step S180 as to whether or not
the first processing has ended. If it is decided in step S180 that
the first processing has ended, first processing end information is
recorded in step S190. More specifically, "0" is set (stored) in
the "first processing" entry in the data table constituting the
processing status management information 492. The first processing
sequence that includes the exclusivity control with relation to the
second processing thus ends.
[0144] Under the control achieved in the first embodiment described
above, executed in conjunction with the first processing, the first
processing (e.g., roughing vacuum processing that does not require
scrubbing) is not executed at any of the remaining processing
chambers if the second processing (e.g., processing of a wafer W
during which gas requiring scrubbing is discharged) is in progress
at a given processing chamber. Thus, as long as the second
processing is in progress at any processing chamber and the
discharge gas is scrubbed at the scrubbing device 300 through the
scrubbing common discharge system 320, the scrubbing device 300 is
not switched over to non-scrubbing discharge through the
non-scrubbing common discharge system 330. As a result, the
discharge gas that needs to be scrubbed is never directly
discharged without first undergoing the scrubbing process at the
scrubbing device 300.
[0145] For instance, while the second processing such as processing
of a wafer W requiring the discharge gas to be scrubbed is in
progress at the processing chamber 200B and the scrubbing discharge
is executed via the scrubbing means 340 at the scrubbing device 300
as shown in FIG. 5, the first processing such as roughing vacuum
processing executed initially at atmospheric pressure, which does
not require discharge gas scrubbing, is not executed at any of the
other processing chambers, e.g., the processing chamber 200A. Thus,
since the switch-over valve 350 at the scrubbing device 300 is
never opened while the second processing is in progress at the
processing chamber 200B, as shown in FIG. 6, the discharge gas from
the processing chamber 200B is not directly discharged without
first undergoing scrubbing at the scrubbing device 300.
[0146] In addition, while the second processing such as processing
of a wafer W is in progress at a given processing chamber, the
first processing such as auto-check processing or maintenance
processing that includes roughing vacuum processing executed
initially at atmospheric pressure is not executed at the other
processing chambers.
[0147] In this case, the entire auto-check processing or the entire
maintenance processing may be designated as the first processing
and the execution thereof may be suspended under the exclusivity
control described above, or only the roughing vacuum processing
executed initially at atmospheric pressure during the auto-check
processing or the maintenance processing may be designated as the
first processing and the execution thereof alone may be suspended
under the exclusivity control. As long as at least the roughing
vacuum processing executed initially at atmospheric pressure is not
simultaneously executed at another processing chamber as the second
processing, i.e., the processing of a wafer W, is in progress in a
given processing chamber, the scrubbing device 300 is not switched
to the non-scrubbing common discharge system 330, and thus, the
discharge gas that needs to be scrubbed is never directly
discharged without first being scrubbed at the scrubbing device
300.
[0148] In the latter case, even though the execution of the
auto-check processing or the maintenance processing at the other
processing chamber can be started while the second processing,
i.e., the processing of the wafer W, is in progress in a given
processing chamber, the exclusivity control comes into effect at
the stage at which the roughing vacuum processing needs to be
executed at atmospheric pressure to disable execution of the
roughing vacuum processing.
[0149] It is to be noted that the exclusivity control does not
apply to execution of the first processing (e.g., roughing vacuum
processing executed initially at atmospheric pressure) at different
processing chambers in the specific example of the first processing
procedure that includes the exclusive processing, as shown in FIG.
12. For this reason, the first processing may be executed
simultaneously at a plurality of processing chambers. In such a
case, the gas discharged from any of the processing chambers where
the first processing is in progress does not need to be scrubbed
and can be directly discharged without first being scrubbed at the
scrubbing means 340 of the scrubbing device 300.
[0150] However, when the first processing (e.g., roughing vacuum
processing, executed initially at atmospheric pressure) is
individually executed at different processing chambers, the
pressure levels in the individual processing chambers may not
match, depending upon the timing with which the first processing is
started in each processing chamber. Under such circumstances, a
backflow of the discharge gas from a processing chamber where the
pressure is at a higher level to a processing chamber where the
pressure is lower may occur. Accordingly, exclusivity control may
also be implemented for individual execution of the first
processing in different processing chambers. In such a case, the
exclusivity control should be executed by substituting the first
processing for the second processing in FIG. 12. Under this
exclusivity control, simultaneous execution of the first processing
at different processing chambers are disallowed and thus, a
backflow of the discharge gas into any of the processing chambers
can be reliably prevented.
[0151] (Specific Example of Control Under which Second Processing
is Executed)
[0152] First, a specific example of control under which the second
processing (e.g., processing of a wafer W) is executed at a given
processing chamber among the processing chambers 200A through 200D
is explained. FIG. 13 presents a flowchart of the specific example
of the control under which the second processing is executed. As
shown in FIG. 13, the execution of the second processing (steps
S260 through S290) at a given processing chamber starts after
executing exclusivity control (steps S200 through S250).
[0153] During the exclusivity control, a decision is made in step
S200 as to whether or not there is a processing chamber waiting in
standby to execute reserved processing. More specifically, a
decision is made as to whether or not the table constituting the
scrubbing device access right reservation information 494 contains
a reservation for processing Uob). This decision is made so as to
confer priority to processing to be executed at another processing
chamber, which has been reserved in the table constituting the
scrubbing device access right reservation information 494 and
awaiting the execution thereof.
[0154] If it is decided in step S200 that there is a processing
chamber waiting in standby for the execution of reserved
processing, i.e., that there is processing (job) for which a
reservation has been made in the table constituting the scrubbing
device access right reservation information 494, the operation
proceeds to step S220 to bring up a display indicating that the
second processing cannot be executed at the display means 450,
before the operation shifts into reservation processing in step
S230 and subsequent steps to be detailed later. As a result,
simultaneous execution of the first processing and the second
processing at different processing chambers is prevented. It is to
be noted that the warning means 490 may be engaged at this time to
warn the operator that the second processing cannot be
executed.
[0155] If, on the other hand, it is decided in step S200 that there
is currently no processing chamber waiting for execution of
reserved processing, i.e., that there is no processing (job) the
execution of which has been reserved in the table constituting the
scrubbing device access right reservation information 494, the
operation proceeds to step S210 to make a decision as to whether or
not the first processing is in progress in another processing
chamber. This decision is made so as to prevent simultaneous
execution of the first processing and the second processing at
different processing chambers. More specifically, the decision is
made based upon the processing status management information 492
stored at the storage means 490.
[0156] If it is decided in step S210 that the first processing
(e.g., roughing vacuum processing executed initially at atmospheric
pressure) is not currently in progress at another processing
chamber, the operation shifts into the processing in step S260 and
subsequent steps, thereby starting the second processing. If, on
the other hand, it is decided in step S210 that the first
processing is currently in progress at another processing chamber,
the operation proceeds to step S220 to bring up a display
indicating that the second processing cannot the executed at the
display means 450. At this time, the warning means 470 may be
engaged to warn the operator that the second processing cannot be
executed.
[0157] Then, the reservation processing is executed in steps S230
through S250. During the reservation processing, an access right to
the scrubbing device 300 is first reserved in step S230. More
specifically, an access right that will allow the use of the
scrubbing device 300 (the common discharge system 310) is reserved
at the data table constituting the scrubbing device access right
reservation information 494 at the storage means 490.
[0158] Next, a decision is made in step S240 as to whether or not
the first processing at the other processing chamber has ended.
This decision is made based upon the processing status management
information 492 at the storage means 490. As the first processing
having been in progress at the other processing ends, the "first
processing" entry corresponding to the other processing chamber in
the processing status management information 492 is switched from
"1" to "0" and accordingly, the first processing at the other
processing chamber can be judged to have ended when the "first
processing" entry is switched to "0". If it is decided in step S240
that the first processing having been in progress at the other
processing chamber has not ended yet, the operation waits in
standby for the first processing at the other processing chamber to
end.
[0159] If it is decided in step S240 that the first processing
having been in progress at the other processing chamber has ended,
the operation proceeds to step S250 to make a decision as to
whether or not an access right to the scrubbing device 300 has been
obtained. This decision is made in correspondence to the order in
which reservations have been registered in the scrubbing device
access right reservation information 494. The decision as to
whether or not an access right to the scrubbing device 300 has been
obtained is made by judging, based upon, for instance, the
processing status management information 492, as to whether or not
the first processing is in progress in another processing chamber.
If the first processing is judged to be not in progress at another
processing chamber, it is decided that an access right to the
scrubbing device 300 has been obtained and, in this case, the
operation shifts to the processing in step S260 and subsequent
steps, thereby starting the second processing.
[0160] If, on the other hand, the first processing is judged to be
in progress in another processing chamber, it is decided that an
access right to the scrubbing device 300 has not been obtained and
the operation waits until an access right to the scrubbing device
300 is obtained. The control follows this flow so as not to execute
the second processing if the first processing is underway at yet
another processing chamber while the first processing is in
progress in a given processing chamber since the exclusivity
control does not apply to concurrent executions of the first
processing at different processing chambers.
[0161] Next, an explanation is given on how the second processing
is started. When starting the second processing, second processing
start information is recorded in step S260. More specifically, "1"
is set (stored) in the "second processing" entry in the data table
constituting the processing status management information 492.
[0162] Next, the second processing is executed in step S270. The
second processing (e.g., processing of a wafer W) is executed by
closing the switch-over valve 350 of the scrubbing device 300 and
thus switching the common discharge system 310 to the scrubbing
common discharge system 320. As a result, the discharge gas from
the processing chamber is first scrubbed via the scrubbing means
340 in is then discharged to, for instance, the plant exhaust
system.
[0163] Next, a decision is made in step S280 as to whether or not
the second processing has ended. If it is decided in step S280 that
the second processing has ended, second processing end information
is recorded in step S290. More specifically, "0" is set (stored) in
the "second processing" entry in the data table constituting the
processing status management information 492. The second processing
sequence that includes the exclusivity control with relation to the
first processing thus ends.
[0164] Under the control achieved in the first embodiment described
above, executed in conjunction with the second processing, the
second processing (e.g., processing on a wafer W executed at low
pressure) is not executed at any of the remaining processing
chambers if the first processing (e.g., roughing vacuum processing
executed initially under high pressure conditions) is in progress
at any processing chamber. Thus, as long as the first processing is
in progress at a given processing chamber and the gas from the
processing chamber is discharged through the non-scrubbing common
discharge system 330, the scrubbing device 300 at the scrubbing
device 300 is not switched over to scrubbing discharge through
which the discharge gas is discharged via the scrubbing common
discharge system 320. As a result, the gas resulting from
processing initially executed at high-pressure, which does not need
to be scrubbed, is not discharged via the scrubbing means 340 of
the scrubbing device 300, thereby reducing the onus on the
scrubbing device 300.
[0165] For instance, while the first processing such as roughing
vacuum processing executed initially at atmospheric pressure, i.e.,
at high-pressure, is in progress at the processing chamber 200B and
the gas from the processing chamber 200B is discharged through
non-scrubbing discharge without going through the scrubbing process
at the scrubbing means 340 of the scrubbing device 300, as shown in
FIG. 7, execution of the second processing such as processing of a
wafer W that needs to be executed under low pressure conditions at
any of the other processing chambers, e.g., the processing chamber
200A, is suspended. Thus, the switch-over valve 350 at the
scrubbing device 300 is not closed while the first processing is in
progress at the processing chamber 200B, as shown in FIG. 8, and
the gas discharged from the processing chamber 200B is not
discharged via the scrubbing means 340 at the scrubbing device 300.
The onus on the scrubbing device 300 is thus reduced.
[0166] It is to be noted that while roughing vacuum processing
started at atmospheric pressure is in progress, the wafer W is held
in standby in, for instance, the common transfer chamber 150,
instead of carrying it into the processing chamber, since there may
be a residual processing gas or a deposit resulting from the
previous processing in the processing chamber and the wafer W held
in standby in the processing chamber may become unintentionally
processed.
[0167] It is to be noted that the first processing described above
may be roughing vacuum processing executed initially at atmospheric
pressure or it may be auto-check processing, maintenance processing
or the like in which roughing vacuum processing is executed
initially at atmospheric pressure, as a part thereof. Accordingly,
while the first processing such as auto-check processing or
maintenance processing is in progress in a given processing
chamber, the second processing such as processing of a wafer W is
not executed in any of the other processing chambers.
[0168] Under these circumstances, the entire auto-check processing
or the entire maintenance processing may be designated as the first
processing and the execution of the second processing at another
processing chamber may be suspended while the first processing is
in progress, as described earlier, or only the roughing vacuum
processing executed initially at atmospheric pressure as part of
the auto-check processing or the maintenance processing alone may
be designated as the first processing and the execution of the
second processing at another processing chamber may be suspended
only while the designated first processing is in progress. As long
as the second processing, e.g., the processing of a wafer W, is not
simultaneously executed in another processing chamber at least
while the roughing vacuum processing executed initially at
atmospheric pressure is in progress at a given processing chamber,
the scrubbing device 300 is not switched to the scrubbing common
discharge system 320 and thus, the gas discharged under high
pressure conditions is not discharged via the scrubbing means 340
at the scrubbing device 300.
[0169] Accordingly, even while auto-check processing or maintenance
processing is in progress at a given processing chamber, the second
processing, i.e., the processing of a wafer W, can be executed at
another processing chamber, unless the roughing vacuum processing
executed initially under atmospheric pressure conditions, as part
of the auto-check processing or the maintenance processing is in
progress. If, on the other hand, the roughing vacuum processing
executed initially under atmospheric pressure conditions as part of
the auto-check processing or the maintenance processing is in
progress in a given processing chamber, the second processing such
as the processing of a wafer W cannot be executed in any of the
other processing chambers.
[0170] Examples of the second processing include processing for
opening the gas supply valve 214 to draw in the processing gas
executed as part of maintenance processing or cleaning processing,
as well as processing of a wafer W. When the gas supply valve 214
is opened, the processing chamber needs to be discharged and, for
this reason, if the processing gas drawn into the processing
chamber requires discharge gas scrubbing, the processing gas needs
to be discharged via the scrubbing means 340 at the scrubbing
device 300 by switching to the scrubbing common discharge system
320. Accordingly, while the first processing such as roughing
vacuum processing executed initially under atmospheric pressure
conditions is in progress in a given processing chamber, the second
processing, e.g., opening the gas supply valve 214, cannot be
executed in any of the other processing chambers.
[0171] It is to be noted that the start and the end of the
processing of a wafer W representing an example of the second
processing in the embodiment may be defined as follows. Namely,
when continuously processing a plurality of wafers W (e.g., a
single lot of wafers) at the subject processing chamber, processing
starts as the continuous processing operation for the lot starts
and ends as the continuous processing operation ends. If, on the
other hand, wafers W are to be individually processed, one wafer at
a time, at the subject processing chamber, the processing starts as
the process recipe execution starts before a wafer W is carried
into the processing chamber and ends as the elimination of the
static electricity in the processing chamber is completed following
the transfer of the processed wafer. If waferless cleaning (WLDC)
is to be subsequently executed by drawing in the processing gas
following the transfer of the outgoing wafer in order to remove any
substances deposited on the interior of the processing chamber, the
wafer processing ends as the waferless cleaning is completed. Since
the use of the scrubbing device 300 must be exclusively awarded to
the processing chamber while the processing of the wafer W is
executed, from the beginning to the end of the processing, it is
necessary to suspend execution of the first processing over the
entire duration of the wafer processing operation.
[0172] In addition, if an error occurs in the substrate processing
apparatus 100 and the processing of the wafer W stops, it may be
necessary to engage the scrubbing device 300 for the subsequent
recovery processing or for processing (such as static electricity
elimination) executed following the recovery processing. In such a
case, the reservations registered in the scrubbing device access
right reservation information 494 should be first canceled and then
a new access right to the scrubbing device 300 for the recovery
processing should be obtained. Likewise, if the operation shifts
into maintenance processing while the subject processing chamber
has been in a processing wait state under the first
processing/second processing exclusivity control, the reservation
registered in the scrubbing device access right reservation
information 494 should be first canceled and then an access right
to the scrubbing device 300 should be newly obtained for the
recovery processing. As described above, when executing recovery
processing or maintenance processing is executed, any existing
reservation registered in the scrubbing device access right
reservation information 494 is first canceled and thus, the problem
of the scrubbing device 300 being unavailable for recovery
processing or maintenance processing on account of an existing
reservation for another processing job in the scrubbing device
access right reservation information 494 does not occur.
[0173] In addition, if the operation shifts into independent
maintenance processing executed by isolating the subject processing
chamber, the first processing/second processing exclusivity control
such as that shown in FIG. 12 or FIG. 13 is not executed for the
subject processing chamber. Accordingly, the first processing or
the second processing can be executed in the subject processing
chamber in conjunction with such independent maintenance
processing, regardless of whether or not the first processing or
the second processing is currently being executed in another
processing chamber. Also, if the operation in a given processing
chamber where processing is underway by engaging the scrubbing
device 300 shifts into independent maintenance processing, the use
of the scrubbing device 300 in combination with the particular
processing chamber may be canceled and the use of the scrubbing
device 300 may be awarded to an other processing chamber with a
reservation registered in the scrubbing device access right
reservation information 494.
[0174] In addition, while an explanation is given above in
reference to the first processing/second processing exclusivity
control achieved in the embodiment on an example in which a
specific type of reservation processing (e.g., steps S130 through
S150 in FIG. 12 or steps S230 through S250 in FIG. 13) is executed
if either of the first processing and the second processing is in
progress at a given processing chamber when the other processing
needs to be executed at another processing chamber, the present
invention is not limited to this example and if either of the first
processing or the second processing is already in progress at a
given processing chamber when the other processing needs to be
executed at another processing chamber, the operation may end in an
error without executing any reservation processing.
[0175] Furthermore, the reservation processing described above does
not need to be executed under the following circumstances. For
instance, when the maintenance processing executed in response to
operator instructions includes the first processing or the second
processing, e.g., wafer processing executed during maintenance,
processing for operating the switch-over valve 270 and the gas
supply valve 214 at the auxiliary discharge system 240 by
themselves, cycle purge processing for discharging residual
processing gas remaining in the processing chamber by alternately
evacuating and charging the chamber so as to switch between a
vacuum and a pressure of one atmosphere, processing for charging
the processing chamber to a pressure of one atmosphere or cleaning
processing, and the subject processing chamber where such
processing is to be executed is set in a processing wait state
under the first processing/second processing exclusivity control
described earlier, the execution of the processing may be disabled
through an interlock without executing the reservation processing
described earlier. Since the substrate processing apparatus 100 is
likely to be monitored by an operator when any of the processing
listed above is to be executed, the processing does not need to be
automatically executed through reservation processing and the
operability of the apparatus improves by enabling free operation by
the operator.
[0176] In addition, while an explanation is given above in
reference to the embodiment on an example in which the discharge
systems 220A through 220D of all the processing chambers 200A
through 200D of the substrate processing apparatus 100 are
connected with the common scrubbing device 300 via the common
discharge system 310, the discharge systems of only some of the
processing chambers may be connected to the scrubbing device via
the common discharge system, as long as the discharge systems of at
least two processing chambers are connected to the scrubbing
device.
[0177] For instance, a first scrubbing device may be connected via
a first common discharge system to the processing chambers 200A and
200B, with a second scrubbing device connected with the processing
chambers 200C and 200D via a second common discharge system. In
this case, the first processing/second processing exclusivity
control in the embodiment will be executed in correspondence to
each of the processing chambers connected to either common
discharge system. Alternatively, a scrubbing device may be
connected to the processing chambers 200A through 200C via a common
discharge system and another scrubbing device may be connected to
the processing chamber 200D alone. In this configuration, the first
processing/second processing exclusivity control achieved in the
embodiment will be executed for the processing chambers 200A
through 200C.
[0178] While an explanation is given above in reference to the
embodiment on an example in which the common discharge system 310
includes the scrubbing common discharge system 320 for evacuating
each processing chamber via the scrubbing means 340 and the
non-scrubbing common discharge system 330 through which discharge
gas is discharged directly without being scrubbed at the scrubbing
means 340, both disposed within the scrubbing device 300, the
present invention is not limited to this example. For instance, the
scrubbing common discharge system 320 alone may be disposed in the
scrubbing device 300, with the non-scrubbing common discharge
system 330 provided as a device independent of the scrubbing device
300. This configuration allows the present invention to be adopted
in conjunction with a scrubbing device 300, which does not include
a non-scrubbing common discharge system 330.
[0179] As explained earlier, the gas supply system 210 may adopt a
structure other than that shown in FIG. 2. It goes without saying
that the present invention may be adopted equally effectively
regardless of a specific structure that may be assumed in the gas
supply system 210 in correspondence to, for instance, the type or
the flow rate of the gas to be supplied into the processing chamber
200. For instance, if multiple types of gases are to be drawn into
the processing chamber, a piping structure that includes a
plurality of gas supply systems each connecting a gas supply source
of a specific type of gas and a gas supply valve may be adopted so
as to allow a mixture of the various types of gases to be drawn
into the processing chamber 200. In such a case, the piping system
may include a plurality of gas supply systems each corresponding to
one of the multiple types of gases to be used for the processing,
or if a mixed gas containing an inert gas is to be used as the
processing gas, a gas supply system for the inert gas may be added
into the processing gas supply system. Moreover, an inert gas
supply system may be added as a supply system for supplying gas to
be used when charging the processing chamber to a pressure of one
atmosphere.
[0180] A structural example that may be adopted in the gas supply
system 210 in FIG. 2, which includes a processing gas supply system
and an inert gas supply system, is now explained in reference to
FIG. 14. In this example, the inert gas supply system is used when
executing wafer processing and also when executing particle
reduction processing by using a gas shock wave. The wafer
processing is executed by continuously supplying the inert gas
(e.g., N.sub.2 gas) at a predetermined flow rate to be used as a
pressure adjusting gas, together with the processing gas, into the
processing chamber. Particles in the processing chamber may be
eliminated with the gas shock wave by continuously supplying the
inert gas (e.g., N.sub.2 gas) at a high flow rate into the
processing chamber where the inert gas is used as, for instance, a
purge gas. As in the explanation given earlier in reference to FIG.
2, the following explanation is given simply by using reference
numeral 200 to refer to a given processing chamber representing the
processing chambers 200A through 200D. Accordingly, the processing
chamber 200 may be any of the processing chambers 200A through
200D, and the gas supply system 210 may be any of the gas supply
systems 210A through 210D corresponding to the individual
processing chambers 200A through 200D.
[0181] The gas supply system 210 in FIG. 14 is constituted by
connecting a piping at which a processing gas supply system 510 and
an inert gas supply system 520 are made to join each other, to the
processing chamber 200. The processing gas supply system 510 may
include, for instance, a processing gas supply source 512 and a gas
supply valve 514. It is to be noted that the processing gas supply
system 510 may instead adopt a piping structure that includes a
plurality of gas supply systems each corresponding to a specific
type of gas constituting the processing gas and disposed in
parallel to one another and allows a mixture of the individual
constituents of the processing gas to be drawn into the processing
chamber 200.
[0182] The inert gas supply system 520 may include, for instance,
an inert gas supply source 522, and may be constituted by
connecting in parallel a low flow rate supply system a first supply
system through which the inert gas from the inert gas supply source
522 can be drawn into the processing chamber 200 at a constant low
flow rate and a high flow rate supply system (a second supply
system) 540 through which the inert gas from the inert gas supply
source 522 can be drawn into the processing chamber 200 at a high
flow rate, set higher than the flow rate at the low flow rate
supply system 530.
[0183] The low flow rate supply system 530 is constituted with a
metering valve 532 through which the flow rate of the inert gas
from the inert gas supply source 522 is adjusted to a predetermined
flow rate and a gas supply valve 534. The metering valve 532 may be
a fixed valve constituted with, for instance, an orifice or a
choke, or it may be a variable valve that enables fine adjustment
of the flow rate. Alternatively, the gas supply valve 534 and the
metering valve 532 may be constituted as an integrated orifice
valve. The low flow rate supply system 530 is engaged to draw the
inert gas such as N.sub.2 gas to be used as a pressure adjusting
gas into the processing chamber 200 when drawing the processing gas
into the processing chamber 200 to execute, for instance, wafer
processing. When the low flow rate supply system 530 is engaged for
such wafer processing, the flow rate of the inert gas, which is
adjusted at the metering valve 532, should be set to a level at
which the pressure in the processing chamber 200 can be
adjusted.
[0184] The high flow rate supply system 540 is connected downstream
of the low flow rate supply system 530 via a gas supply valve 542.
The high flow rate supply system 540 is used for, for instance,
cleaning processing executed by drawing in the inert gas to
eliminate particles and the like present in the processing chamber
200. Such cleaning processing may be particle reduction processing
(NPPC) during which the processing chamber 200 is evacuated while
drawing in the inert gas such as N.sub.2 gas at a high flow rate
and particles and the like having been collected on the inner walls
of the processing chamber 200 are flaked off the inner walls by a
shock wave (a pressure wave transmitted at a speed exceeding the
speed of sound) generated under specific conditions and are
discharged together with the discharge gas. The inert gas flow rate
at the high flow rate supply system 540 engaged for such particle
reduction processing should be set to a level at which particles
and the like in the processing chamber 200 can be eliminated with a
gas shock wave.
[0185] It is to be noted that while the inert gas supply system 520
in the piping structure shown in FIG. 14 includes two supply
systems, i.e., the low flow rate supply system 530 and the high
flow rate supply system 540, the present invention is not limited
to this example. For instance, the inert gas supply system 520 may
be constituted with a single supply system. In such a case, the
flow rate of the inert gas may be adjusted to a low level for wafer
processing and the inert gas flow rate may be adjusted to a high
level for particle reduction processing via a flow regulating
valve. However, since the inert gas is used as the pressure
adjusting gas during the wafer processing, it is necessary to
ensure her that the inert gas is supplied at a constant low flow
rate during the wafer processing in either of the structures
described above.
[0186] While the inert gas supply system 520 may adopt a
single-system structure as described above, it may become difficult
depending upon the capacity of the flow regulating valve, which
needs to be repeatedly adjusted between the high flow rate setting
and the low flow rate setting to sustain a constant low flow rate.
By adopting a two-system structure in the inert gas supply system
520 as shown in FIG. 14, the need for a flow regulating valve for
adjusting the flow rate setting from high to low and vice versa is
eliminated and, as a result, a constant low flow rate can be
sustained at all times with a high level of reliability at low
cost. In addition, the inert gas supply system 520 adopting such a
two-system structure facilitates the switch-over control for the
common discharge system 310 at the scrubbing device 300, as
explained later.
[0187] When processing a wafer W in the processing chamber 200
adopting the piping structure shown in FIG. 14, the processing
chamber 200 is first discharged, as in the case of the processing
chamber 200 adopting the piping structure in FIG. 2, until the
pressure inside the processing chamber 200 is lowered to a
predetermined level while the gate valve of the processing chamber
200 is kept in a closed state. Once the discharge processing is
completed, the gate valve is opened and the wafer W is carried into
the processing chamber 200. After the wafer W is placed on the
stage, the gate valve is closed and the operation shifts to the
processing of the wafer W.
[0188] At this time, the switch-over valve 270 is closed to switch
the discharge system 220 to the main discharge system 230, as shown
in FIG. 15. As the gas supply valve 514 of the processing gas
supply system 510 is opened in this state, the processing gas from
the processing gas supply source 512 is drawn into the processing
chamber 200 and the gas supply valve 534 is opened while leaving
the gas supply valve 542 of the inert gas supply system 520 in a
closed state to draw the inert gas (e.g., N.sub.2 gas) from the
inert gas supply source 522 into the processing chamber 200 via the
low flow rate supply system 530, thereby starting the processing of
the wafer W. During this process, the inert gas acts as a pressure
adjusting gas so as to sustain the pressure inside the processing
chamber 200 at a predetermined level. The wafer W is processed over
a predetermined length of time in this state.
[0189] When the processing gas containing a harmful constituent is
used to process the wafer W, a discharge gas containing a harmful
substance is discharged from the processing chamber 200 as
described above. Accordingly, the switch-over valve 350 of the
scrubbing device 300 is closed to switch the common discharge
system 310 to the scrubbing common discharge system 320. As a
result, the gas discharged from the processing chamber 200 as the
wafer W is processed is first scrubbed and is then discharged to,
for instance, the plant exhaust system.
[0190] Next, after the processing of the wafer W is completed and
the processed wafer is carried out, particle reduction processing
may be executed as described earlier by opening the switch-over
valve 270 and switching the discharge system 220 to the auxiliary
discharge system 240. In this case, the gas supply valve 542 is
opened while the gas supply valve 514 at the processing gas supply
system 510 and the gas supply valve 534 at the inert gas supply
system 520 are sustained in a closed state to draw the inert gas
(e.g., N.sub.2 gas) from the inert gas supply source 522 into the
processing chamber 200 via the high flow rate supply system 540. As
a result, the gas shock wave generated with the inert gas (e.g.,
N.sub.2 gas) flakes off particles having accumulated on the inner
walls and the like at the processing chamber 200, which are then
discharged together with the discharge gas.
[0191] The inert gas such as N.sub.2 gas with no harmful substances
contained therein used in such particle reduction processing does
not need to be scrubbed at the scrubbing device 300. If the inert
gas was discharged via the scrubbing means 340 at the scrubbing
device 300, the onus on the scrubbing device 300 would increase.
Accordingly, the particle reduction processing is executed by
directly discharging the gas from the processing chamber 200
without scrubbing it at the scrubbing means 340, as in the cycle
purge explained earlier. More specifically, the switch-over valve
350 at the scrubbing device 300 is opened to switch the common
discharge system 310 to the non-scrubbing common discharge system
330, as shown in FIG. 16. The onus on the scrubbing device 300 is
thus reduced.
[0192] It is to be noted that while the inert gas may be drawn into
the processing chamber 200 via the high flow rate supply system 540
alone, as shown in FIG. 16, for the particle reduction processing,
or the particle reduction processing may be executed by drawing the
inert gas into the processing chamber 200 via both the high flow
rate supply system 540 and the low flow rate supply system 530 by
opening both the gas supply valves 542 and 534. In this case, the
inert gas can be supplied into the processing chamber 200 in an
even larger quantity.
[0193] In addition, when processing is executed concurrently at the
processing chambers 200A, 200B and the like adopting the piping
structure shown in FIG. 14, exclusivity control is executed in
conjunction with the first processing and the second processing, as
shown in FIGS. 12 and 13. In this case, the processing that
requires the processing gas drawn in via the processing gas supply
system 510 and the inert gas drawn in via the low flow rate supply
system 530, as shown in FIG. 15, e.g., wafer processing, is
executed by switching the common discharge system 310 to the
scrubbing common discharge system 320, and thus constitutes the
second processing. The processing that requires the inert gas drawn
in via the high flow rate supply system 540 (or both the high flow
rate supply system 540 and the low flow rate supply system 530) is
executed by switching the common discharge system 310 to the
non-scrubbing common discharge system 330 and thus constitutes the
first processing.
[0194] Under the exclusivity control, particle reduction processing
equivalent to the first processing is not executed at the
processing chamber 200B and the like while wafer processing
equivalent to the second processing is in progress at, for
instance, the processing chamber 200A, and wafer processing
equivalent to the second processing is not executed in the other
processing chamber 200B and the like while particle reduction
processing equivalent to the first processing is in progress at the
processing chamber 200A. As a result, simultaneous execution of the
first processing such as that described above and the second
processing such as that described above at different processing
chambers are prevented. Thus, in the substrate processing apparatus
having the processing chambers 200 adopting a piping structure such
as that shown in FIG. 14, too, the onus on the scrubbing device 300
is reduced and, at the same time, no discharge gas that requires
scrubbing is directly without first being scrubbed.
[0195] Next, another structural example that may be adopted in the
gas supply system 210 in FIG. 2 is explained in reference to
drawings. FIG. 17 is a block diagram showing another structural
example that may be adopted in the gas supply system 210. In the
example presented in FIG. 17, the inert gas supply system in FIG.
14 is achieved as an inert gas charging system that charges the
processing chamber with inert gas (e.g. N.sub.2 gas) so as to
adjust the pressure in the processing chamber to one atmosphere.
Such an inert gas supply system is used for particle reduction
processing (e.g., two-stage NPPC to be detailed later) in the
processing chamber as well as when charging the processing chamber
to a pressure of one atmosphere.
[0196] In the gas supply system 210 shown in FIG. 17, the piping of
a processing gas supply system 610 and the piping of an inert gas
supply system 620 used as an inert gas charging system are
conjoined and the conjoined piping is connected to the processing
chamber 200 via a main valve 602. The processing gas supply system
610 may include a processing gas supply source 612, an
upstream-side gas supply valve 614, a flow regulator (e.g., a mass
flow controller) 615 and a downstream-side gas supply valve 616. It
is to be noted that the processing gas supply system 610 may adopt
a piping structure that includes a plurality of gas supply systems
each corresponding to a specific type of gas constituting the
processing gas, disposed in parallel to one another, so as to draw
the individual types of gases constituting the processing gas as a
mixture into the processing chamber 200.
[0197] The inert gas supply system 620 may include, for instance,
an inert gas supply source 622 and may be constituted by connecting
in parallel a low flow rate supply system (a first supply system)
through which the inert gas from the inert gas supply source 622
can be drawn into the processing chamber 200 at a constant low flow
rate and a high flow rate supply system (a second supply system)
640 through which the inert gas from the inert gas supply source
622 can be drawn into the processing chamber 200 at a high flow
rate, set higher than the flow rate at the low flow rate supply
system 630.
[0198] The low flow rate supply system 630 is constituted with a
metering valve 632 through which the flow rate of the inert gas
from the inert gas supply source 622 is adjusted to a constant flow
rate and a downstream-side gas supply valve 636. The metering valve
632 may be a fixed valve constituted with, for instance, an orifice
or a choke, or it may be a variable valve that enables fine
adjustment of the flow rate. Alternatively, the downstream-side gas
supply valve 636 and the metering valve 632 may be constituted as
an integrated orifice valve. The high flow rate supply system 640
is connected downstream of the low flow rate supply system 630 via
a downstream-side gas supply valve 646.
[0199] The processing gas supply system 610 and the inert gas
supply system 620 are connected with each other via a communicating
pipe 604. More specifically, the downstream side of the
upstream-side gas supply valve 614 at the processing gas supply
system 610 and the downstream side of the upstream-side gas intake
valve 624 at the inert gas supply system 620 are connected with
each other via the communicating pipe 604 which includes a
communicating valve 606. As the communicating valve 606 is opened,
the inert gas from the inert gas supply system 620 is guided via
the communicating pipe 604 to the flow regulator 615 and the
downstream-side gas supply valve 616 in the processing gas supply
system 610 and the main valve 602, and is then taken into the
processing chamber 200. Thus, the inert gas from the inert gas
supply system 620 can be drawn into the processing chamber 200
after its flow rate is adjusted at the flow regulator 615 of the
processing gas supply system 610.
[0200] Next, a specific example of cleaning processing that may be
executed in the processing chamber 200 adopting the piping
structure shown in FIG. 17 is explained. Such cleaning processing
may be particle reduction processing (NPPC) during which particles
and the like having been collected on the inner walls of the
processing chamber 200 are flaked off the inner walls and the like
by a shock wave (a pressure wave transmitted at a speed exceeding
the speed of sound) generated under specific conditions as the
inert gas such as N.sub.2 gas is briefly drawn into the processing
chamber at a high flow rate and the particles are discharged
together with the discharge gas.
[0201] Such particle reduction processing may be executed under
control executed by the control unit 400 as shown in, for instance,
FIG. 18. FIG. 18 presents a flowchart of a specific example of
control under which particle reduction processing may be executed.
The particle reduction processing (NPPC) in this example includes
two phases of NPPC, i.e., first NPPC (step S300) executed as first
particle reduction processing and second NPPC (step S400) executed
as second particle reduction processing, as shown in FIG. 18. The
first NPPC is regular low pressure NPPC executed in a low-pressure
environment. The second NPPC is a high-pressure NPPC executed in a
high pressure environment, during which cleaning processing is
executed by using a gas shock wave.
[0202] A specific example of the first NPPC processing (step S300)
is now explained in reference to FIG. 19. The first NPPC processing
is started by first executing a pre-execution check in step S310 as
shown in FIG. 19. The pre-execution check is executed to ensure
that the processing chamber 200 is in a state that enables a normal
execution of NPPC. For instance, if wafer processing is in
progress, if a wafer is currently present in the processing
chamber, if an outgoing wafer is being carried out of the
processing chamber or if maintenance work is in progress in the
processing chamber 200 is not in conditions under which normal
execution of NPPC can be carried out.
[0203] The wafer processing may include phases such as a processing
gas drawing phase, a back gas drawing phase during which a back gas
for wafer temperature adjustment or the like is drawn in, a control
phase during which the electrostatic chuck for holding the wafer is
controlled and a control phase during which the high frequency
power sources are controlled. The outgoing wafer transfer may
include a gate opening phase during which the gate to the
processing chamber is opened. The maintenance work may include a
lid opening phase during which the lid of the processing chamber is
opened.
[0204] Under any of those circumstances, the processing chamber 200
is not in an NPPC enabling state. For this reason, the state of the
processing chamber 200 is checked in advance, and if it is decided
that the processing chamber 200 is not in an NPPC enabling state,
the NPPC processing ends in an error, whereas if the processing
chamber 200 is judged to be in an NPPC enabling state, the
processing in step S312 and subsequent steps is executed.
[0205] Main discharge processing is executed in step S312. More
specifically, the processing chamber 200 is evacuated via the main
pump 260 until a predetermined vacuum pressure is achieved in the
chamber. It is to be noted that if the predetermined level of
vacuum pressure is not achieved when a predetermined length of time
has elapsed, a timeout occurs and the processing ends in an error.
In step S314, pressure control via a pressure adjusting valve (APC)
(not shown) at the main discharge system 230 is started in order to
set the pressure inside the processing chamber 200 to a
predetermined cleaning pressure level.
[0206] Then, the inert gas (e.g., N.sub.2 gas) is drawn into the
processing chamber 200 in step S316. The inert gas is drawn in from
the processing gas supply system 610 via the communicating pipe 604
in the step. More specifically, the upstream-side gas supply valve
624 and the communicating valve 606 are opened while leaving the
downstream-side gas supply valves 636 and 646 in the inert gas
supply system 620 in a closed state and, at the same time, the
downstream-side gas supply valve 616 and the main valve 602 are
opened while leaving the upstream-side gas supply valve 614 of the
processing gas supply system 610 in a closed state. As a result,
the inert gas (e.g., N.sub.2 gas) from the inert gas supply source
622 is drawn into the processing chamber 200 from the processing
gas supply system 610 via the communicating pipe 604.
[0207] Then, in step S318, a decision is made as to whether or not
the pressure inside the processing chamber 200 has become stable
and if it is decided that the pressure in the processing chamber
200 has become stable, the operation proceeds to step S320 to
execute voltage application control. In this step, the voltage
applied to the electrostatic chuck used to hold fast the wafer onto
the lower electrode is controlled. In more specific terms, voltage
polarity conversion control during which the voltage applied to the
electrostatic chuck is first set to a positive value, the voltage
is turned off (set to 0) after a predetermined length of time (e.g.
2 sec) elapses, then the voltage applied to the electrostatic chuck
is set to a negative value and the voltage is turned off (set to 0)
after a predetermined length of time (e.g. 2 sec) elapses, is
repeatedly executed over a predetermined number of cycles (e.g.,
five cycles). Through this control, it becomes easier to scatter
particles present inside the processing chamber 200, and thus, the
particles can be removed effectively. Once the voltage application
control ends, the cleaning pressure control is stopped in step S322
by, for instance, fully opening the pressure adjusting valve (APC)
(not shown) of the main discharge system 230.
[0208] Next, the supply of the inert gas is stopped by closing the
upstream-side gas supply valve 624 at the inert gas supply system
620 in step S324. At this time, the communicating valve 606, the
downstream-side gas supply valve 616 of the processing gas supply
system 610 and the main valve 602 are left in an open state. In
this condition, discharge processing is executed to discharge any
residual gas present in the processing gas supply system 610 and
the communicating pipe 604 in step S326.
[0209] Next, main discharge processing is executed again in step
S328. More specifically, the processing chamber 200 is evacuated
via the main pump until a predetermined vacuum state is achieved.
It is to be noted that if the predetermined vacuum state is not
achieved when a predetermined length of time has elapsed, a timeout
occurs and the processing ends in an error. Once the sequence of
the first NPPC is completed as described above, the second NPPC is
executed.
[0210] In reference to FIG. 20, a specific example of the second
NPPC processing (step S400) is explained. After the second NPPC is
started, the main discharge processing is first stopped by closing
the pressure adjusting valve (APC) (not shown) of the main
discharge system 230 in step S410 in FIG. 20. Then, in step S412,
roughing vacuum processing is started. Namely, the processing
chamber 200 is evacuated via the auxiliary discharge system 240 by
driving the auxiliary pump 250. It is desirable to close the
protective valve at the vacuum pressure gauge at the start of the
second NPPC so as to protect the vacuum pressure gauge during the
second NPPC processing.
[0211] Then, in step S414, the inert gas is drawn into the
processing chamber 200 through the inert gas supply system 620,
which is an inert gas charging system to adjust the pressure in the
processing chamber to one atmosphere. In this step, the inert gas
is drawn in by using both the low flow rate supply system 630 and
the high flow rate supply system 640. Namely, the inert gas is
drawn in by opening the upstream-side gas supply valve 624 and also
by opening the downstream-side gas supply valves 636 and 646 and
the main valve 602, as shown in FIG. 22. Then, in step S416, the
operation waits for a predetermined length of time (e.g., 5 sec) to
elapse. Once the predetermined length of time elapses, the
downstream-side gas supply valve 646 at the high flow rate supply
system 630 is closed in step S418 so as to drawn in the inert gas
from the low flow rate supply system 640 alone, as shown in FIG.
23.
[0212] Next, voltage application control is executed in step S420.
The voltage application control executed in this step may be
similar to that executed in step S320. Next, the supply of the
inert gas is stopped in step S422 and the roughing vacuum
processing ends in step S424. More specifically, the upstream-side
gas supply valve 624 and the downstream-side gas supply valve 646
in the inert gas supply system 620 are first closed to stop the
supply of inert gas while roughing vacuum processing is in progress
and the main valve 602 is still in an open state, and then the
operation waits for a predetermined length of time to elapse. As a
result, any residual particles remaining in the processing chamber
can be removed. Once the predetermined length of time elapses, the
auxiliary pump 250 is stopped and the roughing vacuum processing
ends.
[0213] Next, main discharge processing is executed in step S426 by
driving the main pump 260 and thus, the sequence of the second NPPC
processing ends. It is to be noted that the second NPPC processing
may be repeatedly executed over a predetermined number of
cycles.
[0214] During the particle reduction processing (NPPC) shown in
FIG. 18, the NPPC processing is executed over two phases, i.e., the
first NPPC executed in a low-pressure environment and the second
NPPC executed in a high-pressure environment, which enables more
efficient removal of particles and the like present in the
processing chamber 200. In addition, during the second NPPC, a gas
shock wave is generated as the inert gas (N.sub.2 gas) is drawn
into the processing chamber 200 at a high flow rate briefly over
the predetermined length of time (e.g., 5 sec) and particles having
become adhered to the inner walls of the processing chamber 200 and
the like can be flaked off with a high level of efficiency with a
gas shock wave.
[0215] In addition, if the processing to be executed in the
processing chamber 200 does not at least require any discharge gas
scrubbing and starts under high-pressure conditions (e.g., a
pressure equal to or higher than 50 Torr (66.6 hPa)), the common
discharge system 310 is switched to the non-scrubbing common
discharge system 330 during the particle reduction processing
(NPPC) in FIG. 18, but otherwise, the particle reduction processing
(NPPC) in FIG. 18 is executed by switching the common discharge
system 312 to the scrubbing common discharge system 320. Through
these measures, it is ensured that no unnecessary onus is placed on
the scrubbing device 300 during the particle reduction processing
(NPPC) in FIG. 18.
[0216] When the first NPPC and the second NPPC constituting the
particle reduction processing (NPPC) in FIG. 18 are simultaneously
executed in a plurality of processing chambers under low-pressure
conditions with pressure levels inside the individual processing
chambers not exceeding, for instance, 50 Torr (66.6 hPa), the
processing chambers will all be discharged via the scrubbing means
340 by switching the common discharge system 310 to the scrubbing
common discharge system 320, as shown in FIGS. 21 through 23. For
this reason, if the second NPPC is executed by continuously drawing
in the inert gas at a high flow rate, as shown in FIG. 14 and the
inert gas is continuously discharged at a high flow rate from the
plurality of processing chambers simultaneously, the onus placed on
the scrubbing device 300 is bound to increase.
[0217] However, the second NPPC in FIG. 20 is executed by only
briefly drawing in the inert gas at a high flow rate instead of
continuously drawing in the inert gas at a high flow rate. Thus,
even if the second NPPC in FIG. 20 is simultaneously executed at a
plurality of processing chambers, the inert gas is discharged from
the processing chambers at a high flow rate only briefly, which
greatly reduces the onus on the scrubbing device 300 compared to
the onus that would be placed on the scrubbing device 300 by second
NPPC executed by continuously drawing in the inert gas at a high
flow rate.
[0218] It is to be noted that the particle reduction processing
(NPPC) in FIG. 18 may be executed during, for instance, maintenance
work. The particle reduction processing (NPPC) in FIG. 18 may also
be executed over predetermined time intervals or after a
predetermined number of wafers are processed during automatic
inspection processing (auto-check processing). In the latter case,
the purge processing executed by using the inert gas (e.g., N.sub.2
gas) may be stopped before executing the main discharge processing
(step S312) as part of the first NPPC in FIG. 19, information
indicating that NPPC is in progress may be brought up at the
display means 450, the information indicating that the NPPC is
underway may be cleared from the display means 450 after the main
discharge processing (step S426) is executed as part of the second
NPPC in FIG. 20 and then the purge processing that uses the inert
gas (e.g., N.sub.2 gas) may be resumed.
[0219] For instance, if a setting for executing the particle
reduction processing (NPPC in FIG. 18 over predetermined time
intervals or after a predetermined number of wafers have been
processed during automatic inspection processing (auto-check
processing) is selected, the operation may shift into the particle
reduction processing (NPPC) during batch processing of, for
instance, 25 wafers constituting a single lot. Under such
circumstances, if the operation needs to shift into the particle
reduction processing (NPPC) while the purge processing is executed
by using the inert gas (e.g., N.sub.2 gas), the purge processing
executed by using the inert gas must first be stopped. In the case
of maintenance processing, on the other hand, the purge processing
will have been completed before the operation shifts to maintenance
processing and, accordingly, it is not necessary to go through the
sequence of stopping the purge processing executed by using the
inert gas and then resuming the purge processing.
[0220] In addition, the particle reduction processing (NPPC) in
FIG. 18 may be executed in the load-lock chambers 160 as well as
the processing chambers 200. The particle reduction processing
(NPPC) may be repeatedly executed in the load-lock chambers 160
over a plurality of cycles.
[0221] The present invention described in detail above in reference
to the embodiments may be adopted in a system constituted with a
plurality of devices or in an apparatus constituted with a single
device. It will be obvious that the present invention may be
implemented by providing such a system or apparatus with a medium
such as a storage medium having stored therein a software program
for achieving the functions of the embodiments and by reading out
and executing the program stored in a medium such as a storage
medium at a computer (or a CPU or an MPU) constituting part of the
system or the apparatus.
[0222] The functions of the embodiments described above are
achieved in the program itself, read out from the medium such as a
storage medium, whereas the present invention is embodied in the
medium such as a storage medium having the program stored therein.
The medium such as a storage medium in which the program is
provided may be, for instance, a floppy (registered trademark)
disk, a hard disk, an optical disk, a magneto-optical disk, a
CD-ROM, a CD-R. a CD-RW, a DVD-ROM, a DVD-RAM, a DVD-RW, a DVD+RW,
magnetic tape, a nonvolatile memory card or a ROM, or it may be
achieved in the form of a download via a network.
[0223] It is to be noted that the scope of the present invention
includes an application in which an OS or the like operating on the
computer executes the actual processing in part or in whole in
response to the instructions in the program read out by the
computer and the functions of the embodiments are achieved through
the processing thus executed, as well as an application in which
the functions of the embodiments are achieved as the computer
executes the program it has read out.
[0224] The scope of the present invention further includes an
application in which the program read out from the medium such as a
storage medium is first written into a memory in a function
expansion board loaded in the computer or a function expansion unit
connected to the computer, a CPU or the like in the function
expansion board or the function expansion unit executes the actual
processing in part or in whole in response to the instructions in
the program and the functions of the embodiment described above are
achieved through the processing.
[0225] While the invention has been particularly shown and
described with respect to preferred embodiments thereof by
referring to the attached drawings, the present invention is not
limited to these examples and it will be understood by those
skilled in the art that various changes in form and detail may be
made therein without departing from the spirit, scope and teaching
of the invention.
[0226] For instance, while an explanation is given above in
reference to the embodiments on an example in which the present
invention is adopted in a cluster tool-type substrate processing
apparatus that includes a processing unit achieved by connecting a
plurality of processing chambers around a common transfer chamber,
the present invention may also be adopted in any of various types
of substrate processing apparatuses in which the operation stops
upon the occurrence of an error in the apparatuses, such as a
tandem-type substrate processing apparatus achieved by connecting
in parallel a plurality of processing units to a transfer unit,
with each processing unit having a processing chamber connected to
a load-lock chamber.
* * * * *