U.S. patent application number 10/322974 was filed with the patent office on 2003-05-08 for substrate processing system.
This patent application is currently assigned to LSI Logic Corporation. Invention is credited to Catabay, Wilbur G., Kumar, Kiran, Rios, Rudy, Schinella, Richard D., Wang, Zhihai.
Application Number | 20030084587 10/322974 |
Document ID | / |
Family ID | 25183676 |
Filed Date | 2003-05-08 |
United States Patent
Application |
20030084587 |
Kind Code |
A1 |
Kumar, Kiran ; et
al. |
May 8, 2003 |
Substrate processing system
Abstract
An apparatus for performing contaminant sensitive processing on
a substrate. A substrate load chamber receives the substrate from
an ambient contaminant laden environment, and isolates the
substrate from the ambient contaminant laden environment. The
substrate load chamber further forms a first environment of
intermediate cleanliness around the substrate. A substrate pass
through chamber receives the substrate from the substrate load
chamber, and isolates the substrate from the intermediate
cleanliness of the first environment of the substrate load chamber.
The substrate pass through chamber further forms a second
environment of high cleanliness around the substrate. A substrate
transfer chamber receives the substrate from the substrate pass
through chamber, and isolates the substrate from the high
cleanliness of the second environment of the substrate pass through
chamber. The substrate transfer chamber maintains a third
environment of high cleanliness around the substrate, and transfers
the substrate into more than one substrate processing chambers,
where the substrate is selectively transferred into and out of the
more than one substrate processing chambers without leaving the
high cleanliness of the third environment. The substrate transfer
chamber also selectively passes the substrate to the substrate pass
through chamber when the substrate pass through chamber has formed
the high cleanliness of the second environment. The substrate pass
through chamber also receives the substrate from the substrate
transfer chamber, and selectively passes the substrate to the
substrate load chamber when the substrate load chamber has formed
the intermediate cleanliness of the first environment. The
substrate load chamber receives the substrate from the substrate
pass through chamber, and selectively passes the substrate out of
the substrate load chamber and into the ambient contaminant laden
environment when the substrate load chamber is not open to the
substrate pass through chamber.
Inventors: |
Kumar, Kiran; (Sunnyvale,
CA) ; Wang, Zhihai; (Sunnyvale, CA) ; Rios,
Rudy; (San Jose, CA) ; Catabay, Wilbur G.;
(Saratoga, CA) ; Schinella, Richard D.; (Saratoga,
CA) |
Correspondence
Address: |
LSI LOGIC CORPORATION
1621 BARBER LANE
MS D-106, LEGAL DEPARTMENT
MILPITAS
CA
95035
US
|
Assignee: |
LSI Logic Corporation
|
Family ID: |
25183676 |
Appl. No.: |
10/322974 |
Filed: |
December 18, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10322974 |
Dec 18, 2002 |
|
|
|
09802424 |
Mar 9, 2001 |
|
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|
6518193 |
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Current U.S.
Class: |
34/218 ;
257/E21.577; 34/444; 34/611 |
Current CPC
Class: |
C23C 14/566 20130101;
H01L 21/76843 20130101; H01L 21/67167 20130101; C23C 16/4401
20130101; H01L 21/76802 20130101; H01L 21/67017 20130101; H01L
21/67201 20130101 |
Class at
Publication: |
34/218 ; 34/611;
34/444 |
International
Class: |
F26B 019/00; F26B
025/06; C23F 001/00; H01L 021/306; F26B 003/00; F26B 009/00; F26B
013/00; F26B 013/06 |
Claims
What is claimed is:
1. An apparatus for performing contaminant sensitive processing on
a substrate, comprising: a substrate load chamber for receiving the
substrate from an ambient contaminant laden environment, for
isolating the substrate from the ambient contaminant laden
environment, and for forming a first environment of intermediate
cleanliness around the substrate, a substrate pass through chamber
for receiving the substrate from the substrate load chamber, for
isolating the substrate from the intermediate cleanliness of the
first environment of the substrate load chamber, and for forming a
second environment of high cleanliness around the substrate, a
substrate transfer chamber for receiving the substrate from the
substrate pass through chamber, for isolating the substrate from
the high cleanliness of the second environment of the substrate
pass through chamber, for maintaining a third environment of high
cleanliness around the substrate, and for transferring the
substrate into more than one substrate processing chambers, where
the substrate is selectively transferred into and out of the more
than one substrate processing chambers without leaving the high
cleanliness of the third environment, the substrate transfer
chamber also for selectively passing the substrate to the substrate
pass through chamber when the substrate pass through chamber has
formed the high cleanliness of the second environment, the
substrate pass through chamber also for receiving the substrate
from the substrate transfer chamber, and for selectively passing
the substrate to the substrate load chamber when the substrate load
chamber has formed the intermediate cleanliness of the first
environment, and the substrate load chamber for receiving the
substrate from the substrate pass through chamber, and for
selectively passing the substrate out of the substrate load chamber
into the ambient contaminant laden environment when the substrate
load chamber is not open to the substrate pass through chamber.
2. The apparatus of claim 1 wherein the more than one substrate
processing chambers include an etch chamber and a deposition
chamber.
3. The apparatus of claim 1 wherein the more than one substrate
processing chambers include an etch chamber, a titanium deposition
chamber, a titanium nitride deposition chamber, and a tantalum
deposition chamber.
4. The apparatus of claim 1 wherein the more than one substrate
processing chambers include an etch chamber, a clean chamber, a
tantalum deposition chamber, and a copper deposition chamber.
5. The apparatus of claim 1 further comprising a first load lock
for selectively isolating the substrate load chamber from the
substrate pass through chamber.
6. The apparatus of claim 1 further comprising a second load lock
for selectively isolating the substrate pass through chamber from
the substrate transfer chamber.
7. The apparatus of claim 1 further comprising at least one third
load lock for selectively isolating the substrate transfer chamber
from the more than one substrate processing chambers.
8. The apparatus of claim 1 further comprising: a first pumping
system for selectively forming the first environment of
intermediate cleanliness in the substrate load chamber, a second
pumping system for selectively forming the second environment of
high cleanliness in the substrate pass through chamber, and a third
pumping system for selectively forming the third environment of
high cleanliness in the substrate transfer chamber.
9. The apparatus of claim 1 further comprising a first roughing
pump for selectively forming the first environment of intermediate
cleanliness in the substrate load chamber,
10. The apparatus of claim 1 further comprising a first cryogenic
pump for selectively forming the second environment of high
cleanliness in the substrate pass through chamber,
11. The apparatus of claim 1 further comprising a second cryogenic
pump for selectively forming the third environment of high
cleanliness in the substrate transfer chamber,
12. A method of performing contaminant sensitive processing on a
substrate, comprising the steps of: transferring the substrate from
an ambient contaminant laden environment and into a substrate load
chamber, isolating the substrate from the ambient contaminant laden
environment with the substrate load chamber, forming a first
environment of intermediate cleanliness around the substrate in the
substrate load chamber, transferring the substrate from the
intermediate cleanliness of the first environment of the substrate
load chamber and into a substrate pass through chamber, isolating
the substrate from the intermediate cleanliness of the first
environment of the substrate load chamber with the substrate pass
through chamber, forming a second environment of high cleanliness
around the substrate with the substrate pass through chamber,
transferring the substrate from the high cleanliness of the second
environment of the substrate pass through chamber and into a
substrate transfer chamber, isolating the substrate from the high
cleanliness of the second environment of the substrate pass through
chamber with the substrate transfer chamber, maintaining a third
environment of high cleanliness around the substrate with the
substrate transfer chamber, selectively transferring the substrate
into more than one substrate processing chambers, where the
substrate is selectively transferred into and out of the more than
one substrate processing chambers without leaving the high
cleanliness of the third environment, selectively processing the
substrate in the more than one substrate processing chambers,
transferring the substrate to the substrate pass through chamber
from the substrate transfer chamber when the substrate pass through
chamber has formed the high cleanliness of the second environment
and the substrate pass through chamber is not open to the substrate
load chamber, transferring the substrate to the substrate load
chamber from the substrate pass through chamber when the substrate
load chamber has formed the intermediate cleanliness of the first
environment and the substrate pass through chamber is not open to
the substrate transfer chamber, and transferring the substrate out
of the substrate load chamber and into the ambient contaminant
laden environment when the substrate load chamber is not open to
the substrate pass through chamber.
13. The method of claim 12 wherein the step of processing the
substrate in the more than one substrate processing chambers
further comprises: etching the substrate in an etch chamber,
cleaning the substrate in a clean chamber, and depositing a layer
in a deposition chamber.
14. The method of claim 12 wherein the step of processing the
substrate in the more than one substrate processing chambers
further comprises: etching the substrate in an etch chamber,
cleaning the substrate in a clean chamber, and depositing a layer
of titanium in a deposition chamber.
15. The method of claim 12 wherein the step of processing the
substrate in the more than one processing chambers further
comprises: etching the substrate in an etch chamber, cleaning the
substrate in a clean chamber, depositing a layer of tantalum in a
first deposition chamber, and depositing a layer of copper in a
second deposition chamber.
16. The method of claim 12 further comprising the step of
selectively isolating the substrate load chamber from the substrate
pass through chamber with a first load lock.
17. The method of claim 12 further comprising the step of
selectively isolating the substrate pass through chamber from the
substrate transfer chamber with a second load lock.
18. The method of claim 12 further comprising the step of
selectively isolating the substrate transfer chamber from the more
than one substrate processing chambers with at least one third load
lock.
19. The method of claim 12 wherein: the step of forming the first
environment of intermediate cleanliness in the substrate load
chamber further comprises using a first pumping system, the step of
forming the second environment of high cleanliness in the substrate
pass through chamber further comprises using a second pumping
system, and the step of forming the third environment of high
cleanliness in the substrate transfer chamber further comprises
using a third pumping system.
20. A method of forming a via on a substrate of a low dielectric
constant material, comprising the steps of: forming a first
environment of intermediate cleanliness around the substrate with a
substrate load chamber that receives the substrate from an ambient
contaminant laden environment and isolates the substrate from the
ambient contaminant laden environment, forming a second environment
of high cleanliness around the substrate with a substrate pass
through chamber that receives the substrate from the substrate load
chamber and isolates the substrate from the intermediate
cleanliness of the first environment of the substrate load chamber,
maintaining a third environment of high cleanliness around the
substrate with a substrate transfer chamber that receives the
substrate from the substrate pass through chamber and isolates the
substrate from the high cleanliness of the second environment of
the substrate pass through chamber, transferring the substrate into
more than one substrate processing chambers, where the substrate is
selectively transferred into and out of the more than one substrate
processing chambers without leaving the high cleanliness of the
third environment, etching the substrate in an etch chamber to form
a via recess, depositing a titanium adhesion layer in a first
deposition chamber, depositing a titanium nitride diffusion barrier
layer in a second deposition chamber, selectively transferring the
substrate to the substrate pass through chamber from the substrate
transfer chamber when the substrate pass through chamber has formed
the high cleanliness of the second environment, selectively
transferring the substrate to the substrate load chamber from the
substrate pass through chamber at a time when the substrate load
chamber has formed the intermediate cleanliness of the first
environment, and selectively transferring the substrate out of the
substrate load chamber into the ambient contaminant laden
environment at a time when the substrate load chamber is not open
to the substrate pass through chamber.
Description
FIELD
[0001] This invention relates to the field of integrated circuit
fabrication. More particularly this invention relates to a system
for performing contaminant sensitive processing on a substrate.
BACKGROUND
[0002] A variety of different materials are typically used in
integrated circuit fabrication processes. Many of these materials
are highly susceptible to various contaminants. In addition, some
processes, at intermediate points, create sites or structures that
are very susceptible to contamination. For example, when trenches
or holes are etched into dielectric films, the dielectric films
tend to be extremely susceptible to contaminants in the atmosphere
such as oxygen, nitrogen, rare gases, hydrocarbons, water vapor and
other atmospheric contaminants. When exposed to such, the etched
portions of the dielectric layer tend to attract such
contaminants.
[0003] In the specific case of low dielectric constant materials,
which tend to be porous in nature, the adsorption of contaminants
tends to be even greater. Thus, when a low dielectric constant
material is etched, the etched portions tend to adsorb
contaminants. Then, when a thin material layer is subsequently
deposited over the etched portions, such as when a diffusion
barrier is formed in a via, the contaminants absorbed in the low
dielectric constant material in the area of the etched via tend to
outgas and interfere with the uniform and desirable deposition of
the deposited layer. This condition tends to cause problems with
the integrated circuit, such as barrier layers that are porous or
otherwise defection, and which do not exhibit the desired barrier
properties.
[0004] As a more specific example, when a titanium adhesion layer
is deposited in an etched silicon oxide via, and then the titanium
adhesion layer is followed by a titanium nitride diffusion barrier
layer, and then the titanium nitride diffusion barrier layer is
followed by a tungsten plug deposition, the resultant structure
often exhibits a breakdown of the barrier diffusion layer, which is
typically referred to as poisoned vias or poisoned plugs.
[0005] What is needed, therefore, is a system for forming
structures on a substrate, where the substrate and the various
layers are not exposed to a contaminant laden environment.
SUMMARY
[0006] The above and other needs are met by an apparatus for
performing contaminant sensitive processing on a substrate. A
substrate load chamber receives the substrate from an ambient
contaminant laden environment, and isolates the substrate from the
ambient contaminant laden environment. The substrate load chamber
further forms a first environment of intermediate cleanliness
around the substrate.
[0007] A substrate pass through chamber receives the substrate from
the substrate load chamber, and isolates the substrate from the
intermediate cleanliness of the first environment of the substrate
load chamber. The substrate pass through chamber further forms a
second environment of high cleanliness around the substrate.
[0008] A substrate transfer chamber receives the substrate from the
substrate pass through chamber, and isolates the substrate from the
high cleanliness of the second environment of the substrate pass
through chamber. The substrate transfer chamber maintains a third
environment of high cleanliness around the substrate, and transfers
the substrate into more than one substrate processing chambers,
where the substrate is selectively transferred into and out of the
more than one substrate processing chambers without leaving the
high cleanliness of the third environment.
[0009] The substrate transfer chamber also selectively passes the
substrate to the substrate pass through chamber when the substrate
pass through chamber has formed the high cleanliness of the second
environment. The substrate pass through chamber also receives the
substrate from the substrate transfer chamber, and selectively
passes the substrate to the substrate load chamber when the
substrate load chamber has formed the intermediate cleanliness of
the first environment. The substrate load chamber receives the
substrate from the substrate pass through chamber, and selectively
passes the substrate out of the substrate load chamber and into the
ambient contaminant laden environment when the substrate load
chamber is not open to the substrate pass through chamber.
[0010] Because there is a substrate pass through chamber between
the substrate load chamber and the substrate transfer chamber, the
high cleanliness environment of the substrate transfer chamber is
never exposed to the intermediate cleanliness of the substrate load
chamber, or the contaminant laden ambient environment. Thus, the
substrate pass through chamber, by forming an environment of high
cleanliness before transferring a substrate to or accepting a
substrate from the substrate transfer chamber, protects and helps
maintain the high cleanliness of the environment of the substrate
transfer chamber. Therefore, those contaminant sensitive processes
that are performed in the various substrate processing chambers are
not exposed to the environment of intermediate cleanliness or to
the contaminant laden ambient environment, and the intermediate
structures which may be created by these various processes are
likewise not exposed to the environments of lesser cleanliness.
[0011] In another aspect of the invention, a method of performing
contaminant sensitive processing on a substrate is given. The
substrate is transferred from an ambient contaminant laden
environment and into a substrate load chamber. The substrate is
isolated from the ambient contaminant laden environment with the
substrate load chamber, and the substrate load chamber forms a
first environment of intermediate cleanliness around the
substrate.
[0012] The substrate is transferred from the intermediate
cleanliness of the first environment of the substrate load chamber
and into a substrate pass through chamber, where the substrate is
isolated from the intermediate cleanliness of the first environment
of the substrate load chamber. A second environment of high
cleanliness is formed around the substrate with the substrate pass
through chamber.
[0013] The substrate is transferred from the high cleanliness of
the second environment of the substrate pass through chamber and
into a substrate transfer chamber, where a third environment of
high cleanliness is maintained around the substrate. The substrate
is selectively transferred into more than one substrate processing
chambers, where the substrate is selectively transferred into and
out of the more than one substrate processing chambers without
leaving the high cleanliness of the third environment. The
substrate is selectively processed in the more than one substrate
processing chambers.
[0014] The substrate is transferred to the substrate pass through
chamber from the substrate transfer chamber when the substrate pass
through chamber has formed the high cleanliness of the second
environment and the substrate pass through chamber is not open to
the substrate load chamber. The substrate is transferred to the
substrate load chamber from the substrate pass through chamber when
the substrate load chamber has formed the intermediate cleanliness
of the first environment and the substrate pass through chamber is
not open to the substrate transfer chamber. The substrate is
transferred out of the substrate load chamber and into the ambient
contaminant laden environment when the substrate load chamber is
not open to the substrate pass through chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Further advantages of the invention are apparent by
reference to the detailed description when considered in
conjunction with the figures, which are not to scale so as to more
clearly show the details, wherein like reference numbers indicate
like elements throughout the several views, and wherein:
[0016] FIG. 1 is a functional block diagram of an apparatus
according to the present invention,
[0017] FIG. 2 is cross sectional diagram of a substrate, including
a layer,
[0018] FIG. 3 is a cross sectional diagram of a via etched in the
layer of the substrate,
[0019] FIG. 4 is a cross sectional diagram of an adhesion layer
deposited in the via of the substrate,
[0020] FIG. 5 is a cross sectional diagram of a barrier layer
deposited in the via of the substrate, and
[0021] FIG. 6 is a cross sectional diagram of a plug layer
deposited in the via of the substrate.
DETAILED DESCRIPTION
[0022] Referring now to FIG. 1, there is depicted an apparatus 10
according to the present invention. Substrates are transferred into
and out of the apparatus 10 via a substrate load chamber 12, which
can be selectively isolated from the contaminant laden ambient
environment around the apparatus 10 via a load lock mechanism 32.
By contaminant laden environment, it is not necessarily meant that
the ambient environment is filthy. Rather, it is intended to mean
that the ambient environment contains some sort of material that is
detrimental to a material, process, or structure that is to be
deposited, used, or exposed at a point in time during the desired
processing of the substrate. Thus, even oxygen or water, such as
water vapor, may be considered a contaminant within the present
context. It is anticipated that the load lock 32 of the substrate
load chamber 12 will open up into a clean room facility.
[0023] Once the substrate is brought within the substrate load
chamber 12, the load lock 32 is closed, isolating the substrate
from the contaminant laden ambient environment. An environment of
intermediate cleanliness is preferably formed around the substrate
once it is within the substrate load chamber 12. This is preferably
accomplished by drawing a vacuum within the substrate load chamber
12, such as by using a first pumping system 26 that is in
communication with the substrate load chamber 12 via a vacuum line
40. In the most preferred embodiment, the first pumping system 26
is a roughing pump, such as a rotary vane pump, which reduces the
pressure within the substrate load chamber 12 to at least about
10.sup.-3 torr.
[0024] By reducing the pressure within the substrate load chamber
12 in this manner, a first environment of intermediate cleanliness
if formed. The first environment has an intermediate cleanliness
because much of the matter of the contaminant laden ambient
environment has been removed by drawing a vacuum on the first
environment. Thus, much of what is detrimental to the later
processes, materials, and structures has been removed from the
first environment. Further, the first environment is not as clean
as is ultimately desired, and thus the first environment is
designated as having an intermediate cleanliness that is somewhere
between the contaminant laden ambient environment and the cleaner
environment that is ultimately desired.
[0025] The substrate is brought into a substrate pass through
chamber 14, such as by opening a load lock 34 between the substrate
load chamber 12 and the substrate pass through chamber 14. In the
preferred embodiment, the load lock 34 between the substrate pass
through chamber 14 and the substrate load chamber 12 is not opened
unless the load lock 32 is closed and the first environment of
intermediate cleanliness has been formed in the substrate load
chamber 12. In this manner, the substrate pass through chamber 14
is kept isolated from the contaminant laden ambient
environment.
[0026] Once the substrate is brought within the substrate pass
through chamber 14, the load lock 34 is closed, isolating the
substrate from the intermediate cleanliness of the first
environment of the substrate load chamber 12. A second environment
of high cleanliness is preferably formed around the substrate once
it is within the substrate pass through chamber 14. This is
preferably accomplished by drawing a vacuum within the substrate
pass through chamber 14, such as by using a second pumping system
28 that is in communication with the substrate pass through chamber
14 via a vacuum line 42. In the most preferred embodiment, the
second pumping system 28 is a cryogenic pump, or some other high
vacuum type pump such as a diffusion pump or molecular pump, which
reduces the pressure within the substrate pass through chamber 14
to at least about 10.sup.-7 torr. In another embodiment, the first
pumping system 26 and the second pumping system 28 are the same
pumping system that is appropriately valved to the substrate pass
through chamber 14 and the substrate load chamber 12.
[0027] By reducing the pressure within the substrate pass through
chamber 14 in this manner, a second environment of high cleanliness
if formed. The second environment has a high cleanliness because an
additional amount of the matter of the intermediate cleanliness
environment has been removed by drawing a higher vacuum on the
second environment. Thus, even more of what is detrimental to the
later processes has been removed from the second environment. The
second environment may still not be as clean as is ultimately
desired, for a variety of reasons. For example, because the
substrate pass through chamber 14 is intermittently exposed to the
intermediate cleanliness of the first environment, it may not be
able to become as clean as an environment that is not
intermittently exposed to the intermediate cleanliness of the first
environment, but which is rather more isolated from sources of
contaminants.
[0028] The substrate is brought into a substrate transfer chamber
16, such as by opening a load lock 36 between the substrate pass
through chamber 14 and the substrate transfer chamber 16. In the
preferred embodiment, the load lock 36 between the substrate pass
through chamber 14 and the substrate transfer chamber 16 is not
opened unless the load lock 34 between the substrate pass through
chamber 14 and the substrate load chamber 12 is closed and the
second environment of high cleanliness has been formed in the
substrate pass through chamber 14. In this manner, the substrate
transfer chamber 16 is kept isolated from the intermediate
cleanliness of the first environment in the substrate load chamber
12.
[0029] Once the substrate is brought within the substrate transfer
chamber 16, the load lock 36 is closed, isolating the substrate
from the high cleanliness environment of the substrate pass through
chamber 14. An environment of high cleanliness is preferably
maintained around the substrate once it is within the substrate
transfer chamber 16. This is preferably accomplished by drawing a
vacuum within the substrate transfer chamber 16, such as by using a
third pumping system 30 that is in communication with the substrate
transfer chamber 16 via a vacuum line 44. In the most preferred
embodiment, the third pumping system 30 is a cryogenic pump, or
some other high vacuum type pump such as a diffusion pump or
molecular pump, which reduces the pressure within the substrate
transfer chamber 16 to about 10.sup.-8 torr. Thus, the environment
of high cleanliness within the substrate transfer chamber 16 is
preferably even cleaner than that formed within the substrate pass
through chamber 14.
[0030] In one embodiment, the first pumping system 26, the second
pumping system 28, and the third pumping system 30 are all the same
pumping system, which is appropriately valved to the substrate
transfer chamber 16, the substrate pass through chamber 14, and the
substrate load chamber 12.
[0031] With the substrate inside of the substrate transfer chamber
16, the substrate may now be selectively transferred into and out
of various processing chambers, such as first processing chamber
18, second processing chamber 20, third processing chamber 22, and
fourth processing chamber 24. It is appreciated that the number of
processing chambers may be either greater than or less than the
number depicted in FIG. 1 and described in this embodiment. Most
preferably, the processing chambers are each selectively isolated
from the substrate transfer chamber 16, such as by load locks
38.
[0032] With the processing chambers isolated from the contaminant
laden ambient environment and the first environment of intermediate
cleanliness, the processes conducted within the processing
chambers, the material used within the processing chambers, and the
intermediate structures formed within the processing chambers are
all isolated from the contaminants within those relatively
contaminated environments. Thus, processes, materials, and
structures which are sensitive to the contaminants within the
ambient environment or the intermediate cleanliness of the first
environment may be more safely processed within the processing
chambers.
[0033] For example, FIG. 2 depicts a substrate having a bottom
layer 102 and a top layer 100. In FIG. 3, a via 104 has been etched
within the top layer 100, which via 104 extends down to the bottom
layer 102. In a specific example where the top layer 100 is a
porous dielectric layer, such as a low dielectric constant layer,
the freshly etched sidewalls of the via 104 tend to be extremely
hydroscopic and readily adsorb water from an ambient environment.
Thus, it is most preferred to etch vias 104 within one of the
processing chambers of the apparatus 10, such as within the first
processing chamber 18, so that the resultant structure, the etched
via 104, is not exposed to undue levels of the water vapor
contamination.
[0034] After the via 104 is etched, the substrate is preferably
transferred to another chamber for further processing, such as to
the second processing chamber 20. In the second processing chamber
20, a layer of a material may be deposited over the clean surfaces
of the via 104. For example, as depicted in FIG. 4, a thin layer of
an adhesion material 106, such as titanium, may be deposited in the
via 104. After the adhesion layer 106 is deposited, the substrate
may be removed from the apparatus 10 as described below. However,
in a most preferred embodiment, the cleanliness of the environment
within the substrate transfer chamber 16 is more fully utilized by
processing the substrate further.
[0035] For example, as depicted in FIG. 5, an additional layer,
such as a barrier layer 108 may be deposited over the adhesion
layer 106. The barrier layer 108 may be of a material such as
titanium nitride, that is deposited in the third processing chamber
22. After the barrier layer 108 is deposited, the substrate may be
removed from the apparatus 10 as described below. However, in a
most preferred embodiment, the cleanliness of the environment
within the substrate transfer chamber 16 is more fully utilized by
processing the substrate further.
[0036] For example, as depicted in FIG. 6, and additional layer,
such as a plug layer 110 maybe deposited over the barrier layer
108. The plug layer 110 may be of a material such as tantalum, that
is deposited in the fourth processing chamber 24. After the plug
layer 110 is deposited, the substrate is preferably removed from
the apparatus 10.
[0037] In other embodiments, the via 104 is etched in the first
processing chamber 18, and the etched via 104 is then cleaned in
the second processing chamber 20. An adhesion layer 106 of titanium
is then deposited by sputter deposition in the third processing
chamber 22, and a barrier layer 108 of titanium nitride is
deposited by chemical vapor deposition in the fourth processing
chamber 24. Alternately, after the clean in the second processing
chamber 20 is performed, a barrier layer of tantalum is sputter
deposited in the third processing chamber 22, and a layer 110 of
copper is sputter deposited in the fourth processing chamber
24.
[0038] It is appreciated that the number of process steps performed
within the apparatus 10, the materials described in the specific
examples above, and the types of process steps so described are all
by way of example only. In various embodiments, different numbers
and types of process steps may be performed within the apparatus
10.
[0039] The substrate is withdrawn from the apparatus 10 by
transferring it from the substrate transfer chamber 16 when the
second environment of high cleanliness has been formed in the
substrate pass through chamber 14, and the load lock 34 between the
substrate pass through chamber 14 and the substrate load chamber 12
is closed. The load lock 36 between the substrate transfer chamber
16 is then closed, and the load lock 34 is opened when the first
environment of intermediate cleanliness has been formed within the
substrate load chamber 12 and the load lock 32 is closed. The
substrate is then transferred into the substrate load chamber 12,
and the load lock 34 between the substrate pass through chamber 14
and the substrate load chamber 12 is closed. Finally, the load lock
32 is opened when the load lock 34 is closed, and the substrate is
withdrawn from the apparatus 10 into the contaminant laden ambient
environment.
[0040] Thus, by using the apparatus 10 according to the method as
described above, all of the processes, materials, and structures
that are preferably isolated from the contaminant laden ambient
environment are so isolated, and the substrate is only exposed to
the contaminant laden ambient environment at such points in the
processing when such exposure is not unduly detrimental to the
exposed materials and structures on the substrate.
[0041] The foregoing description of preferred embodiments for this
invention have been presented for purposes of illustration and
description. They are not intended to be exhaustive or to limit the
invention to the precise form disclosed. Obvious modifications or
variations are possible in light of the above teachings. The
embodiments are chosen and described in an effort to provide the
best illustrations of the principles of the invention and its
practical application, and to thereby enable one of ordinary skill
in the art to utilize the invention in various embodiments and with
various modifications as is suited to the particular use
contemplated. All such modifications and variations are within the
scope of the invention as determined by the appended claims when
interpreted in accordance with the breadth to which they are
fairly, legally, and equitably entitled.
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