U.S. patent application number 14/468796 was filed with the patent office on 2015-03-05 for substrate processing method, substrate processing apparatus and storage medium.
The applicant listed for this patent is Tokyo Electron Limited. Invention is credited to Miyako Kaneko, Itaru Kanno, Takehiko Orii.
Application Number | 20150064911 14/468796 |
Document ID | / |
Family ID | 52583827 |
Filed Date | 2015-03-05 |
United States Patent
Application |
20150064911 |
Kind Code |
A1 |
Kaneko; Miyako ; et
al. |
March 5, 2015 |
SUBSTRATE PROCESSING METHOD, SUBSTRATE PROCESSING APPARATUS AND
STORAGE MEDIUM
Abstract
Productivity can be improved. A substrate processing method
includes a processing liquid supplying process of supplying a
processing liquid, which contains a volatile component and forms a
film on a substrate, onto the substrate on which a pre-treatment,
which requires atmosphere management or time management after the
pre-treatment, is performed; and an accommodating process of
accommodating, in a transfer container, the substrate on which the
processing liquid is solidified or cured by volatilization of the
volatile component.
Inventors: |
Kaneko; Miyako; (Nirasaki
City, JP) ; Orii; Takehiko; (Nirasaki City, JP)
; Kanno; Itaru; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Tokyo Electron Limited |
Tokyo |
|
JP |
|
|
Family ID: |
52583827 |
Appl. No.: |
14/468796 |
Filed: |
August 26, 2014 |
Current U.S.
Class: |
438/694 ;
118/72 |
Current CPC
Class: |
B05B 16/20 20180201;
B05B 12/14 20130101; B05B 9/00 20130101; B05B 13/0228 20130101;
H01L 21/6715 20130101; B05B 7/2497 20130101; H01L 21/76814
20130101; H01L 21/02063 20130101 |
Class at
Publication: |
438/694 ;
118/72 |
International
Class: |
H01L 21/67 20060101
H01L021/67; B05B 9/00 20060101 B05B009/00; H01L 21/3105 20060101
H01L021/3105; H01L 21/306 20060101 H01L021/306; H01L 21/02 20060101
H01L021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 27, 2013 |
JP |
2013-176086 |
Feb 6, 2014 |
JP |
2014-021599 |
Feb 6, 2014 |
JP |
2014-021710 |
Claims
1. A substrate processing method, comprising: a processing liquid
supplying process of supplying a processing liquid, which contains
a volatile component and forms a film on a substrate, onto the
substrate on which a pre-treatment, which requires atmosphere
management or time management after the pre-treatment, is
performed; and an accommodating process of accommodating, in a
transfer container, the substrate on which the processing liquid is
solidified or cured by volatilization of the volatile
component.
2. The substrate processing method of claim 1, wherein the
pre-treatment is a process in which a portion to be modified by
being exposed to the atmosphere is formed on a surface of the
substrate.
3. The substrate processing method of claim 1, further comprising:
a unloading process of taking out the substrate accommodated in the
transfer container after the processing liquid supplying process;
and a removing process of removing the solidified or cured
processing liquid from the substrate after the unloading
process.
4. The substrate processing method of claim 3, further comprising:
a post-treatment process of performing a preset post-treatment on
the substrate after the removing process.
5. The substrate processing method of claim 4, wherein the
pre-treatment is a process in which dry etching or ashing is
performed on the substrate before the processing liquid supplying
process, and the post-treatment is a process in which wet cleaning
is performed on the substrate after the removing process.
6. The substrate processing method of claim 4, wherein the
pre-treatment is a process in which dry etching or ashing is
performed on the substrate before the processing liquid supplying
process, and the post-treatment is a process in which dry etching
is performed on the substrate after the removing process.
7. The substrate processing method of claim 4, wherein the
pre-treatment is a process in which a metal film is formed in the
substrate before the processing liquid supplying process, and the
post-treatment is a process in which a metal film is formed on the
substrate after the removing process.
8. The substrate processing method of claim 4, wherein the
pre-treatment is a process in which wet cleaning is performed on
the substrate before the processing liquid supplying process, and
the post-treatment is a process in which a metal film is formed on
the substrate after the removing process.
9. The substrate processing method of claim 4, wherein the
pre-treatment is a process in which wet cleaning is performed on
the substrate before the processing liquid supplying process, the
processing liquid is a liquid of a sublimation material, and in the
removing process, the solidified or cured processing liquid is
removed from the substrate by sublimation.
10. The substrate processing method of claim 1, further comprising:
an other surface process of processing, in a state that an entire
main surface of the substrate is covered with the solidified or
cured processing liquid, an other surface of the substrate.
11. The substrate processing method of claim 1, further comprising:
a pre-treatment process of performing the pre-treatment on the
substrate.
12. The substrate processing method of claim 3, wherein, in the
removing process, the solidified or cured processing liquid is
removed from the substrate by supplying a removing liquid.
13. The substrate processing method of claim 12, wherein the
removing liquid contains an anticorrosive material for a metal
wiring formed in the substrate.
14. A substrate processing apparatus, comprising: a mounting unit
configured to mount thereon a transfer container accommodating a
plurality of substrates therein; a processing liquid supplying unit
configured to supply a processing liquid, which contains a volatile
component and forms a film on a substrate, onto the substrate on
which a pre-treatment, which requires atmosphere management or time
management after the pre-treatment, is performed; and a substrate
transfer device configured to transfer the substrate, on which the
processing liquid is solidified or cured by volatilization of the
volatile component, to the mounting unit and accommodate the
substrate in the transfer container mounted on the mounting
unit.
15. The substrate processing apparatus of claim 14, further
comprising: a pre-treatment unit configured to perform the
pre-treatment on the substrate.
16. The substrate processing apparatus of claim 14, further
comprising: an other surface processing unit configured to process,
in a state that an entire main surface of the substrate is covered
with the solidified or cured processing liquid, an other surface of
the substrate.
17. The substrate processing apparatus of claim 15, further
comprising: a first block including the pre-treatment unit; a
second block including the processing liquid supplying unit; and a
connecting unit that has an internal space blocked from an
atmosphere and connects the first block and the second block to
each other.
18. A substrate processing apparatus comprising: a mounting unit
configured to mount thereon a transfer container accommodating a
plurality of substrates therein; a removing unit configured to
remove, from a substrate onto which atmosphere management or time
management is performed by supplying a processing liquid, which
contains a volatile component and forms a film on the substrate, on
the substrate and by allowing the processing liquid to be
solidified or cured by volatilization of the volatile component,
the solidified or cured processing liquid; a post-treatment unit
configured to perform a preset post-treatment on the substrate from
which the solidified or cured processing liquid is removed by the
removing unit; and a substrate transfer device configured to
transfer the substrate, which is post-processed by the
post-treatment unit, to the mounting unit and accommodate the
substrate in the transfer container mounted on the mounting
unit.
19. The substrate processing apparatus of claim 18, further
comprising: an other surface processing unit configured to process,
in a state that an entire main surface of the substrate is covered
with the solidified or cured processing liquid, an other surface of
the substrate.
20. The substrate processing apparatus of claim 18, further
comprising: a first block including the mounting unit, the
substrate transfer device and the post-treatment unit; a second
block including the removing unit; and a connecting unit that has
an internal space blocked from an atmosphere and connects the first
block and the second block to each other.
21. A computer-readable storage medium having stored thereon
computer-executable instructions that, in response to execution,
cause a substrate processing apparatus to perform a substrate
processing method as claimed in claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Japanese Patent
Application Nos. 2013-176086, 2014-021599 and 2014-021710 filed on
Aug. 27, 2013, Feb. 6, 2014 and Feb. 6, 2014, respectively, the
entire disclosures of which are incorporated herein by
reference.
TECHNICAL FIELD
[0002] The embodiments described herein pertain generally to a
substrate processing method, a substrate processing apparatus and a
storage medium.
BACKGROUND
[0003] Conventionally, there is known a dry etching process in
which a dry etching process is performed on a substrate such as a
semiconductor wafer to expose a part of a metal wiring formed
within the substrate (see, for example, Patent Document 1).
[0004] If, however, the substrate is exposed for a long time after
the metal wiring within the substrate is exposed through such a dry
etching process, an adverse effect such as oxidation of the exposed
metal wiring or the like may be caused. For this reason, there is
set a time limit (Q-time) in exposure time after the dry etching
process.
[0005] Patent Document 1: Japanese Patent Laid-open Publication No.
2010-027786
[0006] In the above-described conventional technology, however,
time management is required to keep the time limit (Q-time). Thus,
productivity may be decreased due to the increase of the number of
required processes.
[0007] The problem that productivity is decreased may also occur
when performing a wet etching process, a film forming process, or
the like as well as when performing the dry etching process.
SUMMARY
[0008] In view of the foregoing problem, example embodiments
provide a substrate processing method, a substrate processing
apparatus and a storage medium capable of improving
productivity.
[0009] In one example embodiment, a substrate processing method
includes a processing liquid supplying process of supplying a
processing liquid, which contains a volatile component and forms a
film on a substrate, onto the substrate on which a pre-treatment,
which requires atmosphere management or time management after the
pre-treatment, is performed; and an accommodating process of
accommodating, in a transfer container, the substrate on which the
processing liquid is solidified or cured by volatilization of the
volatile component.
[0010] In accordance with the example embodiment, it is possible to
improve productivity.
[0011] The foregoing summary is illustrative only and is not
intended to be in any way limiting. In addition to the illustrative
aspects, embodiments, and features described above, further
aspects, embodiments, and features will become apparent by
reference to the drawings and the following detailed
description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In the detailed description that follows, embodiments are
described as illustrations only since various changes and
modifications will become apparent to those skilled in the art from
the following detailed description. The use of the same reference
numbers in different figures indicates similar or identical
items.
[0013] FIG. 1A is a diagram for describing a substrate processing
method in accordance with a first example embodiment;
[0014] FIG. 1B is a diagram for describing the substrate processing
method in accordance with the first example embodiment;
[0015] FIG. 1C is a diagram for describing the substrate processing
method in accordance with the first example embodiment;
[0016] FIG. 2 is a diagram illustrating a schematic configuration
of a substrate processing system in accordance with the first
example embodiment;
[0017] FIG. 3 is a diagram illustrating a schematic configuration
of a first processing apparatus;
[0018] FIG. 4 is a diagram illustrating a schematic configuration
of a second processing apparatus;
[0019] FIG. 5 is a schematic diagram depicting an example
configuration of a dry etching unit;
[0020] FIG. 6 is a schematic diagram depicting an example
configuration of a first liquid processing unit;
[0021] FIG. 7 is a schematic diagram depicting an example
configuration of a second liquid processing unit;
[0022] FIG. 8 is a flowchart for describing a process sequence of
processing a substrate in accordance with the first example
embodiment;
[0023] FIG. 9A is a diagram showing an example of a rear surface
cleaning process;
[0024] FIG. 9B is a diagram showing an example of the rear surface
cleaning process
[0025] FIG. 10 is a diagram illustrating another example of the
rear surface cleaning process;
[0026] FIG. 11 is a diagram illustrating still another example of
the rear surface cleaning process;
[0027] FIG. 12 is a diagram depicting a schematic configuration of
a first processing apparatus in accordance with a third example
embodiment;
[0028] FIG. 13 is a diagram depicting a schematic configuration of
a second processing apparatus in accordance with the third example
embodiment;
[0029] FIG. 14 is a diagram depicting a schematic configuration of
a second processing apparatus in accordance with a fourth example
embodiment;
[0030] FIG. 15 is a diagram depicting a schematic configuration of
a removing unit in accordance with the fourth example
embodiment;
[0031] FIG. 16 is a diagram depicting a schematic configuration of
a second processing apparatus in accordance with a fifth example
embodiment; and
[0032] FIG. 17 is a table showing example processes to which the
film forming liquid supplying process and the removing process are
applied.
DETAILED DESCRIPTION
[0033] In the following detailed description, reference is made to
the accompanying drawings, which form a part of the description. In
the drawings, similar symbols typically identify similar
components, unless context dictates otherwise. Furthermore, unless
otherwise noted, the description of each successive drawing may
reference features from one or more of the previous drawings to
provide clearer context and a more substantive explanation of the
current example embodiment. Still, the example embodiments
described in the detailed description, drawings, and claims are not
meant to be limiting. Other embodiments may be utilized, and other
changes may be made, without departing from the spirit or scope of
the subject matter presented herein. It will be readily understood
that the aspects of the present disclosure, as generally described
herein and illustrated in the drawings, may be arranged,
substituted, combined, separated, and designed in a wide variety of
different configurations, all of which are explicitly contemplated
herein.
[0034] Hereinafter, a substrate processing method, a substrate
processing apparatus, and a storage medium in accordance with
example embodiments will be described in detail with reference to
the accompanying drawings. It should be noted herein that the
example embodiments are not limiting.
First Example Embodiment
Substrate Processing Method
[0035] First, a substrate processing method in accordance with a
first example embodiment will be elaborated with reference to FIG.
1A to FIG. 1C. FIG. 1A to FIG. 1C are diagrams for describing the
substrate processing method of the first example embodiment.
[0036] In accordance with, the substrate processing method of the
first example embodiment, it is possible to process a substrate
such as a semiconductor wafer (hereinafter, simply referred to as
"wafer W"), in which at least a part of a metal wiring formed
therein is exposed, without being restricted by Q-time.
[0037] Here, the term "Q-time" means, for example, a time limit set
in the exposure time after a dry etching in order to suppress the
metal wiring exposed by the dry etching from being oxidized.
[0038] Once the Q-time is set, time management for keeping the
Q-time is required. Accordingly, productivity may be decreased due
to the increase of the number of required processes. Further, if
the set Q-time is short, line management may be difficult. Thus,
there is a concern that the productivity is decreased since the
line management is complicated.
[0039] As depicted in FIG. 1A, a wafer W has, for example, a wiring
layer 101, a liner film 103 and an interlayer insulating film 104.
The wiring layer 101, the liner film 103 and the interlayer
insulating film 104 are stacked on top of each other in this
sequence. A Cu wiring 102 as an example of a metal wiring is formed
in the wiring layer 101.
[0040] Further, the wafer W also has a via hole 106. The via hole
106 is formed by the dry etching. The via hole 106 is extended to
the wiring layer 101, and a surface of the Cu wiring 102 is exposed
at a bottom of the via hole 106.
[0041] In the substrate processing method in accordance with the
first example embodiment, as depicted in FIG. 1B, a processing
liquid, which contains a volatile component and is configured to
form a film on the wafer W (hereinafter, simply referred to as
"film forming liquid"), is supplied onto the wafer W. To elaborate,
in the first example embodiment, a film forming liquid for forming
a topcoat film on the wafer W (hereinafter, referred to as "topcoat
liquid") is supplied onto the wafer W.
[0042] Here, the topcoat film refers to a protection film coated on
a top surface of a resist film in order to suppress an immersion
liquid from being introduced into the resist film. Here, the
immersion liquid may be a liquid for use in, for example, liquid
immersion exposure in a lithography process.
[0043] As the volatile component contained in the topcoat liquid is
volatilized, the topcoat liquid supplied on the wafer W undergoes
volume shrinkage to be solidified or cured into a topcoat film (see
FIG. 1C). Further, the topcoat liquid also includes an acrylic
resin of which volume tends to be shrunk while being solidified or
cured. The volume shrinkage of the topcoat liquid is also caused by
cure shrinkage of this acrylic resin as well. Here, the term "being
solidified" implies changing into a solid, and the term "being
cured" implies that molecules are interlinked to be a polymer
(e.g., cross-linking, polymerization, etc.).
[0044] If the topcoat film is formed on the wafer W, the Cu wiring
102 exposed by the dry etching is covered with the topcoat film. In
this state, the wafer W is accommodated into a transfer
container.
[0045] According to the substrate processing method of the first
example embodiment, by protecting the exposed Cu wiring 102 with
the topcoat film, the exposed Cu wiring 102 may be suppressed from
being adversely influenced by, for example, oxidation. Thus, the
Q-time need not be set. Since the Q-time is unnecessary, the time
management for observing the Q-time is not needed, so that
complication of line management that might be accompanied by
observance of the Q-time can be avoided. Accordingly, in accordance
with the substrate processing method of the first example
embodiment, productivity can be improved.
[0046] Further, a reaction product P grows as a residual gas in the
dry etching reacts with moisture or oxygen in the atmosphere.
However, in accordance with the substrate processing method of the
first example embodiment, by protecting the exposed Cu wiring 102
with the topcoat film, growth of the reaction product P can be
suppressed. Accordingly, an adverse influence from the reaction
product P, such as deterioration of electrical characteristics or
decrease of yield, can be suppressed.
[0047] Further, in the substrate processing method in accordance
with the first example embodiment, after the wafer W accommodated
into the transfer container is taken out, there is performed a
process of removing the topcoat film formed on the wafer W. Through
this process of removing the topcoat film, the reaction product P
such as polymer, which is generated by dry etching or ashing, can
be removed.
[0048] To elaborate, a removing liquid configured to remove the
topcoat film is supplied onto the topcoat film. In the first
example embodiment, an alkali developer is used as the removing
liquid.
[0049] By supplying the alkali developer, the topcoat film is
peeled off from the wafer W. At this time, the reaction product P
remaining on the wafer W is also peeled off from the wafer W along
with the topcoat film. Accordingly, the reaction product P can be
removed.
[0050] As stated above, according to the substrate processing
method of the first example embodiment, since the reaction product
can be removed without using chemical action, it is possible to
suppress damage on the Cu wiring 102 that might be caused by the
etching or the like.
[0051] Thus, in accordance with the substrate processing method of
the first example embodiment, it is possible to remove the reaction
product P remaining on the wafer W after the dry etching or ashing,
while suppressing damage on the wafer W. Further, the topcoat film
is efficiently removed from the wafer W without performing the
pattern exposure after formed on the wafer W.
[0052] The topcoat liquid undergoes volume shrinkage to be
solidified or cured into the topcoat film. The reaction product P
remaining on the wafer W can be removed from the wafer W by a
distortion (tensile force) caused by the volume shrinkage of the
topcoat liquid.
[0053] Since the volume shrinkage of the topcoat liquid occurs as a
result of the volatilization of the volatile component and the cure
shrinkage of the acrylic resin, a volume shrinkage rate thereof may
be higher than that of a film forming liquid containing a volatile
component only. Thus, the reaction product P can be peeled off from
the wafer W forcibly. Especially, since the degree of cure
shrinkage of the acrylic resin is higher than that of other resins
such as an epoxy resin, the acrylic resin can effectively remove
the reaction product P, so that the acrylic resin is suitable for
the topcoat liquid.
[0054] Further, the topcoat film is swelled when it is peeled off
by the alkali developer. Thus, in accordance with the substrate
processing method of the first example embodiment, it is possible
to remove the reaction product P from the wafer W forcibly through
volume expansion caused by the swelling of the topcoat film as well
as the volume shrinkage caused by the volatilization of the topcoat
liquid.
[0055] Further, in the first example embodiment, by using the
alkali liquid to remove the reaction product P, the removing
efficiency may be increased.
[0056] By supplying the alkali developer, zeta potentials having
the same polarity are generated on the surfaces of the wafer W and
the reaction product P. The reaction product P peeled off from the
wafer W by the volume change of the topcoat liquid is charged with
the zeta potential having the same polarity as that of the wafer W,
so that the reaction product P and the wafer W are repelled against
each other. As a result, the reaction product P can be suppressed
from being re-attached to the wafer W.
[0057] As mentioned above, after the reaction product P is removed
from the wafer W or the like through the volume shrinkage of the
topcoat film, by generating the zeta potentials having the same
polarity on the wafer W and the reaction product P, it is possible
to suppress the reaction product P from being re-attached to the
wafer W. Thus, the removing efficiency for the reaction product P
can be increased.
[0058] Further, the alkali developer may contain at least one of,
but not limited to, ammonia, TMAH (Tetra Methyl Ammonium
Hydroxide), and a choline aqueous liquid.
[0059] Further, according to the substrate processing method of the
first example embodiment, it is also possible to remove the
reaction product P that has entered the via hole 106, which has
been difficult to be removed in a cleaning method using a physical
force, for example.
[0060] The topcoat film formed on the wafer W is completely removed
from the wafer W. Thus, after the topcoat film is removed, the
wafer W returns to the state before the topcoat liquid is supplied,
i.e. a state in which the Cu wiring 102 is exposed.
[0061] <Configuration of Substrate Processing System>
[0062] Now, a substrate processing system configured to perform the
above-described substrate processing method will be explained with
reference to FIG. 2. FIG. 2 is a diagram depicting a schematic
configuration of the substrate processing system in accordance with
the first example embodiment
[0063] As depicted in FIG. 2, the substrate processing system 1 in
the first example embodiment includes a first processing apparatus
2 as a pre-treatment apparatus and a second processing apparatus 3
as a post-treatment apparatus. Further, the substrate processing
system 1 also includes a first control device 4A and a second
control device 4B.
[0064] The first processing apparatus 2 is configured to perform
the dry etching or supply a topcoat liquid onto the wafer W, and
the second processing apparatus 3 is configured to supply the
alkali developer onto the wafer W processed by the first processing
apparatus 2.
[0065] The first control device 4A may be implemented by, but not
limited to, a computer and includes a control unit 401 and a
storage unit 402. The storage unit 402 includes a storage device
such as a RAM (Random Access Memory), a ROM (Read Only Memory), a
hard disk, etc., and is configured to store therein programs for
controlling various kinds of processes performed in the first
processing apparatus 2. The control unit 401 may be, but not
limited to, a CPU (Central Processing Unit). The control unit 401
reads out the programs from the storage unit 402 and executes the
programs to control the operation of the first processing apparatus
2.
[0066] Likewise, the second control device 4B may also be
implemented by, for example a computer and includes a control unit
403 and a storage unit 404. The storage unit 404 includes a storage
device such as a RAM, a ROM, a hard disk, etc., and is configured
to store therein programs for controlling various kinds of
processes performed in the second processing apparatus 3. The
control unit 403 may be, but not limited to, a CPU. The control
unit 403 reads out the programs from the storage unit 404 and
executes the programs to control the operation of the second
processing apparatus 3.
[0067] Here, the programs may be stored in a computer-readable
storage medium and installed in the storage unit 402 of the first
control device 4A or the storage unit 404 of the second control
device 4B from the storage medium. The computer-readable storage
medium may include, but not limited to, a hard disk HD, a flexible
disk (FD), a compact disk (CD), a magnet optical disk (MO), a
memory card, and so forth.
[0068] <Configuration of First Processing Apparatus>
[0069] Now, a configuration of the first processing apparatus 2
will be discussed with reference to FIG. 3. FIG. 3 is a diagram
depicting a schematic configuration of the first processing
apparatus 2. In the following description, to clarify a positional
relationship, X, Y and Z axes orthogonal to each other are defined,
and a positive direction on the Z axis is set as a vertical upward
direction.
[0070] As shown in FIG. 3, the first processing apparatus 2
includes a loading/unloading station 5 and a processing station 6.
The loading/unloading station 5 and the processing station 6 are
located adjacent to each other.
[0071] The loading/unloading station 5 includes a mounting unit 10
and a transfer unit 11. The mounting unit 10 is configured to mount
thereon a multiple number of transfer containers (hereinafter,
referred to as "carriers C") accommodating therein multiple wafers
W in a horizontal posture.
[0072] The transfer unit 11 is located adjacent to the mounting
unit 10 and includes therein a substrate transfer device 111. The
substrate transfer device 111 includes a wafer holding device
configured to hold the wafer W. Further, the substrate transfer
device 111 is configured to be movable in the horizontal direction
and the vertical direction and rotatable about a vertical axis.
This substrate transfer device 111 serves to transfer the wafer W
between the carrier C and the processing station 6 by using the
wafer holding device.
[0073] To elaborate, the substrate transfer device 111 is
configured to take out a wafer W from the carrier C mounted on the
mounting unit 10 and load the wafer W into a dry etching unit 12 of
the processing station 6 to be described later. Further, the
substrate transfer device 111 is also configured to take out the
wafer W from a first liquid processing unit 14 of the processing
station 6 to be described later and return the wafer W back into
the carrier C on the mounting unit 10.
[0074] The processing station 6 is provided adjacent to the
transfer unit 11. The processing station 6 includes the dry etching
unit 12, a load lock chamber 13 and the first liquid processing
unit 14.
[0075] The dry etching unit 12 corresponds to an example
pre-treatment unit and is configured to perform a dry etching
process on the wafer W loaded therein by the substrate transfer
device 111. Through this dry etching process, the via hole 106 is
formed, and the Cu wiring 102 (see FIG. 1A) within the wafer W is
exposed.
[0076] Further, the dry etching process is performed in a
depressurized state. Moreover, in the dry etching unit 12, an
ashing process of removing unnecessary resist can also be performed
after the dry etching process.
[0077] The load lock chamber 13 may switch an internal pressure
thereof between an atmospheric pressure and a depressurized
pressure. A non-illustrated substrate transfer device is provided
within the load lock chamber 13. Upon the completion of the process
in the dry etching unit 12, the processed wafer W is unloaded from
the dry etching unit 12 by the non-illustrated substrate transfer
device of the load lock chamber 13, and then, is loaded into the
first liquid processing unit 14.
[0078] To elaborate, the inside of the load lock chamber 13 is
maintained in the depressurized state until the wafer W is unloaded
from the dry etching unit 12. Then, after the unloading of the
wafer W is completed, an inert gas such as nitrogen or argon is
supplied into the load lock chamber 13 and the inside of the load
lock chamber 13 is switched into the atmospheric pressure state.
Under this atmospheric pressure state, the wafer W is loaded into
the first liquid processing unit 14.
[0079] Accordingly, since the wafer W is blocked from the exterior
air until it is loaded into the first liquid processing unit 14
after unloaded from the dry etching unit 12, the exposed Cu wiring
102 may be suppressed from being oxidized.
[0080] Subsequently, the first liquid processing unit 14 performs a
film forming liquid supplying process of supplying the topcoat
liquid onto the wafer W. As stated above, the topcoat liquid
supplied on the wafer W undergoes volume shrinkage to be solidified
or cured into the topcoat film. As a result, the exposed Cu wiring
102 is covered with the topcoat film.
[0081] Upon the completion of the film forming liquid supplying
process, the processed wafer W is accommodated into the carrier C
by the substrate transfer device 111, and then, is transferred into
the second processing apparatus 3.
[0082] <Configuration of Second Processing Apparatus>
[0083] Now, a configuration of the second processing apparatus 3
will be explained with reference to FIG. 4. FIG. 4 is a diagram
depicting a schematic configuration of the second processing
apparatus.
[0084] As shown in FIG. 4, the second processing apparatus 3
includes a loading/unloading station 7 and a processing station 8.
The loading/unloading station 7 and the processing station 8 are
provided adjacent to each other.
[0085] The loading/unloading station 7 includes a mounting unit 16
and a transfer unit 17. The mounting unit 16 is configured to mount
thereon a multiple number of carriers C.
[0086] The transfer unit 17 is located adjacent to the mounting
unit 16 and includes therein a substrate transfer device 171 and a
transit unit 172. The substrate transfer device 171 includes a
wafer holding device configured to hold thereon the wafer W.
Further, the substrate transfer device 171 is configured to be
movable in a horizontal direction and a vertical direction and
rotatable about a vertical axis. This substrate transfer device 171
serves to transfer the wafer W between the carrier C and the
transit unit 172 by using the wafer holding device.
[0087] The processing station 8 is provided adjacent to the
transfer unit 17. The processing station 8 includes a transfer unit
18 and multiple second liquid processing units 19. The multiple
liquid processing units 19 are arranged at both sides of the
transfer unit 18 side by side.
[0088] The transfer unit 18 includes therein a substrate transfer
device 181. The substrate transfer device 181 has a wafer holding
device configured to hold the wafer W. Further, the substrate
transfer device 181 is configured to be movable in a horizontal
direction and a vertical direction and rotatable about a vertical
axis. This substrate transfer device 181 serves to transfer the
wafer W between the transit unit 172 and the second liquid
processing unit 19 by using the wafer holding device.
[0089] In the second processing apparatus 3, the substrate transfer
device 171 of the loading/unloading station 7 is configured to take
out, from the carrier C, the wafer W processed by the first
processing apparatus 2, and then, is configured to mount the wafer
W on the transit unit 172. The wafer W mounted on the transit unit
172 is unloaded from the transit unit 172 by the substrate transfer
device 181 of the processing station 8, and then, is loaded into
the second liquid processing unit 19.
[0090] In the second liquid processing unit 19, a process of
removing the topcoat film by supplying the alkali developer onto
the wafer W is performed. In this process, as the topcoat film is
peeled off, the reaction product P left on the wafer W is also
removed. Further, in this second liquid processing unit 19, the
wafer W from which the topcoat film is removed is cleaned by a
chemical liquid. Here, a DHF (Dilute HydroFluoric acid) is used as
the chemical liquid.
[0091] Subsequently, the wafer W is unloaded from the second liquid
processing unit 19 by the substrate transfer device 181, and then,
mounted on the substrate transit unit 172. Then, the processed
wafer W mounted on the transit unit 172 is returned back to the
carrier C of the mounting unit 16 by the substrate transfer device
171.
[0092] <Configuration of Dry Etching Unit>
[0093] Now, a configuration of each unit included in the first
processing apparatus 2 and the second processing apparatus 3 will
be explained. First, a configuration of the dry etching unit 12 of
the first processing apparatus 2 will be described with reference
to FIG. 5. FIG. 5 is a schematic diagram illustrating an example
configuration of the dry etching unit 12.
[0094] As depicted in FIG. 5, the dry etching unit 12 includes a
hermetically sealed chamber 201 configured to accommodate therein a
wafer W, and a mounting table 202 configured to mount thereon the
wafer W in a horizontal posture is provided within the chamber 201.
The mounting table 202 includes a temperature control device 203
configured to control a temperature of the wafer W to a preset
value by cooling or heating the wafer W. A loading/unloading
opening (not shown) through which the wafer W is loaded and
unloaded into and from the load lock chamber 13 is formed at a
sidewall of the chamber 201.
[0095] A shower head 204 is provided at a ceiling of the chamber
201, and a gas supply line 205 is connected to the shower head 204.
The gas supply line 205 is connected to an etching gas supply
source 207 via a valve 206, and a preset etching gas is supplied to
the shower head 204 from the etching gas supply source 207. The
shower head 204 is configured to introduce the etching gas supplied
from the etching gas supply source 207 into the chamber 201.
[0096] The etching gas supplied from the etching gas supply source
207 may be, but not limited to, a CH.sub.3F gas, a CH.sub.2F.sub.2
gas, a CF.sub.4 gas, an O.sub.2 gas, an Ar gas, or the like.
[0097] A gas exhaust device 209 is connected to a bottom of the
chamber 201 via a gas exhaust line 208. The inside of the chamber
201 is maintained at a depressurized pressure by the gas exhaust
device 209.
[0098] The dry etching unit 12 is configured as described above.
While depressurizing the inside of the chamber 201 by using the gas
exhaust device 209, the etching gas is supplied into the chamber
201 from the shower head 204, so that the wafer W mounted on the
mounting table 202 is dry-etched. As a result, the via hole 106
(see FIG. 1A) is formed in the wafer W, and the Cu wiring 102 is
exposed.
[0099] In the dry etching unit 12, after dry-etching the interlayer
insulating film 104 (see FIG. 1A) by using, for example, a resist
film as a mask, an ashing process of removing the resist film may
also be performed.
[0100] <Configuration of First Liquid Processing Unit>
[0101] Now, the first liquid processing unit 14 of the first
processing apparatus 2 will be explained with reference to FIG. 6.
FIG. 6 is a schematic diagram illustrating an example configuration
of the first liquid processing unit 14.
[0102] As depicted in FIG. 6, the first liquid processing unit 14
includes a chamber 20, a substrate holding device 30, liquid supply
units 40_1 and 40_2, and a collecting cup 50.
[0103] The chamber 20 is configured to accommodate therein the
substrate holding device 30, the liquid supply unites 40_1 and 40_2
and the collecting cup 50. A FFU (Fan Filter Unit) 21 is provided
at a ceiling of the chamber 20. The FFU 21 generates a downflow in
the chamber 20.
[0104] The FFU 21 is connected to an inert gas supply source 23 via
a valve 22. The FFU 21 is configured to discharge an inert gas such
as an N.sub.2 gas supplied from the inert gas supply source 23 into
the chamber 20. In this way, by using the inert gas as a downflow
gas, the exposed Cu wiring 102 (see FIG. 1A) can be suppressed from
being oxidized.
[0105] The substrate holding device 30 includes a rotating/holding
unit 31 configured to hold a wafer W while rotating the wafer W;
and a fluid supply unit 32 which is inserted through a hollow
portion 314 of the rotating/holding unit 31 and is configured to
supply a gas toward a rear surface of the wafer W.
[0106] The rotating/holding unit 31 is provided at a substantially
central portion of the chamber 20. A holding member 311 configured
to hold the wafer W from a lateral side thereof is provided on a
top surface of the rotating/holding unit 31. The wafer W is
horizontally held by the holding member 311 while slightly spaced
apart from the top surface of the rotating/holding unit 311.
[0107] Further, the rotating/holding unit 31 also includes a
driving device 312 having, for example, a motor and a belt that
delivers a rotary power of the motor to the rotating/holding unit
31. The rotating/holding unit 31 is rotated about a vertical axis
by operating the driving device 312. As the rotating/holding device
31 is rotated, the wafer W held on the rotating/holding unit 31 is
also rotated as one body with the rotating/holding unit 31.
Further, the rotating/holding unit 31 is rotatably supported at the
chamber 20 and the collecting cup 50 via a bearing 313.
[0108] The fluid supply unit 32 is inserted through the hollow
portion 314 in a central portion of the rotating/holding unit 31. A
flow path 321 is formed within the fluid supply unit 32, and an
N.sub.2 supply source 34 is connected to the flow path 321 via a
valve 33. The fluid supply unit 32 supplies an N.sub.2 gas from the
N.sub.2 gas supply source 34 to the rear surface of the wafer W
through the valve 33 and the flow path 321.
[0109] The N.sub.2 gas supplied via the valve 33 has a high
temperature (e.g., about 90.degree. C.) and is used in a
volatilization accelerating process to be described later.
[0110] When receiving the wafer W from the non-illustrated
substrate transfer device of the load lock chamber 13, the fluid
supply unit 32 is raised by a non-illustrated elevating device, and
the substrate holding device 30 mounts the wafer W on
non-illustrated supporting pins provided on a top surface of the
fluid supply unit 32. Thereafter, the substrate holding device 30
lowers the fluid supply unit 32 to a preset position to deliver the
wafer W onto the holding member 311 of the rotating/holding unit
31. Further, when transferring the processed wafer W to the
substrate transfer device 111, the substrate holding unit 30 raises
the fluid supply unit 32 by using the non-illustrated elevating
device and mounts the processed wafer W held by the holding member
311 on the non-illustrated supporting pins. Then, the substrate
holding device 30 delivers the wafer W mounted on the
non-illustrated supporting pins onto the substrate transfer device
111.
[0111] The liquid supply unit 40_1 includes nozzles 41a to 41c, an
arm 42 and a rotating/elevating device 43.
[0112] A DHF supply source 45a is connected to the nozzle 41a via a
valve 44a; a DIW supply source 45b is connected to the nozzle 41b
via a valve 44b; and an IPA supply source 45c is connected to the
nozzle 41c via a valve 44c. A DHF supplied from the nozzle 41a is a
dilute hydrofluoric acid which is diluted to a preset concentration
that does not cause corrosion of the Cu wiring 102. Further, the
arm 42 is configured to support the nozzles 41a to 41c
horizontally, and the rotating/elevating device 43 is configured to
rotate and move the arm 42 up and down.
[0113] The liquid supply unit 40_1 is configured to supply, onto
the wafer W, a preset chemical liquid (here, DHF) from the nozzle
41a, DIW (pure water) as a kind of rinse liquid from the nozzle
41b, and IPA (isopropyl alcohol) as a kind of drying solvent from
the nozzle 41c.
[0114] Further, the liquid supply unit 40_2 includes nozzles 41d
and 41e, an arm 42 configured to support the nozzles 41d and 41e
horizontally; and a rotating/elevating device 43 configured to
rotate and move the arm 42 up and down. A MIBC supply source 45d is
connected to the nozzle 41d via a valve 44d, and a topcoat liquid
supply source 45e is connected to the nozzle 41e via a valve
44e.
[0115] The liquid supply unit 40_2 is configured to supply MIBC
(4-methyl-2-pentanol) as a solvent having affinity with the topcoat
liquid onto the wafer W from the nozzle 41d, and supply the topcoat
liquid onto the wafer W from the nozzle 41e.
[0116] The MIBC is also contained in the topcoat liquid and has
affinity with the topcoat liquid. Besides the MIBC, PGME (propylene
glycol monomethyl ether), PGMEA (Propylene glycol monomethyl ether
acetate), or the like may be used as the solvent having affinity
with the topcoat liquid.
[0117] Further, although the dedicated nozzles 41a to 41e are
provided for the respective processing liquids in this example
embodiment, a single nozzle may be shared for the multiple the
processing liquids. If the nozzle is shared, however, a processing
liquid remaining in the nozzle or a pipeline needs to be first
discharged out in a case where the processing liquids are required
not to be mixed, for example. Accordingly, the corresponding
processing liquid may be consumed unnecessarily. In contrast, by
providing the dedicated nozzles 41a to 41e, such a process of
discharging the processing liquid need not be performed, so that
waste of the processing liquid can be avoided.
[0118] The collecting cup 50 is provided to surround the
rotating/holding unit 31 and is configured to collect a processing
liquid dispersed from the wafer W by the rotation of the
rotating/holding unit 31. A liquid drain opening 51 is formed at a
bottom of the collecting cup 50, and the processing liquid
collected by the collecting cup 50 is drained out from the liquid
drain opening 51 to an outside of the first liquid processing unit
14. Further, a gas exhaust opening 52, through which the N.sub.2
gas supplied from the fluid supply unit 32 or the inert gas
supplied from the FFU 21 is exhausted to the outside of the first
liquid processing unit 14, is also formed at the bottom of the
collecting cup 50.
[0119] <Configuration of Second Liquid Processing Unit>
[0120] Now, a configuration of the second liquid processing unit 19
included in the second processing apparatus 3 will be described
with reference to FIG. 7. FIG. 7 is a schematic diagram depicting
an example configuration of the second liquid processing unit
19.
[0121] As depicted in FIG. 7, the second liquid processing unit 19
includes, within a chamber 60, a substrate holding device 70, a
liquid supply unit 80 and a collecting cup 90.
[0122] The substrate holding device 70 has a rotating/holding unit
71, a supporting column 72 and a driving unit 73. The
rotating/holding unit 71 is provided at a substantially central
portion of the chamber 60. A holding member 711 configured to hold
a wafer W from a lateral side thereof is provided on a top surface
of the rotating/holding unit 71. The wafer W is horizontally held
by the holding member 711 while slightly spaced apart from the top
surface of the rotating/holding unit 71. The supporting column 72
is a vertically extended member. A base end of the supporting
column 72 is rotatably supported by the driving unit 73, and a
leading end of the supporting column 72 is configured to
horizontally support the rotating/holding unit 71. The driving unit
73 is configured to rotate the supporting column 72 about a
vertical axis.
[0123] The substrate holding device 70 configured as described
above rotates the rotating/holding unit 71, which is supported on
the supporting column 72, by rotating the supporting column 72
through the driving unit 73, so that the wafer W held on the
rotating/holding unit 71 is also rotated.
[0124] The liquid supply unit 80 includes nozzles 81a to 81c, an
arm 82 and a rotating/elevating device 83.
[0125] The nozzle 81a is connected to a DHF supply source 85a via a
valve 84a, the nozzle 81b is connected to an alkali developer
supply source 85b via a valve 84b, and the nozzle 81c is connected
to a DIW supply source 85c via a valve 84c. The arm 82 is
configured to horizontally support the nozzles 81a to 81c. The
rotating/elevating device 83 is configured to rotate and move the
arm 82 up and down.
[0126] The liquid supply unit 80 is configured to supply, onto the
wafer W, a DHF as a preset chemical liquid from the nozzle 81a, the
alkali developer as the removing liquid for removing the topcoat
film from the nozzle 81b, and the DIW as the rinse liquid from the
nozzle 81c.
[0127] The alkali developer supplied from the nozzle 81b contains
an anticorrosive material that suppresses corrosion of the Cu
wiring 102. Accordingly, it is possible to remove the topcoat film
while suppressing damage on the Cu wiring 102 in a removing liquid
supplying process to be described later. Further, the DHF supplied
from the nozzle 81a is diluted to a preset concentration that does
not incur corrosion of the Cu wiring 102.
[0128] The collecting cup 90 is placed to surround the
rotating/holding unit 71 to suppress the processing liquids from
being dispersed. A liquid drain opening 91 is formed at a bottom of
the collecting cup 90, and the processing liquids collected by the
collecting cup 90 are drained out of the second liquid processing
unit 19 from the liquid drain opening 91.
[0129] As described above, the second liquid processing unit 19 in
accordance with the first example embodiment corresponds to a
removing unit configured to remove the topcoat film from the wafer
W and, also, an example post-treatment unit configured to perform a
preset post-treatment on the wafer W from which the topcoat film
has been removed.
[0130] <Operations of Substrate Processing System>
[0131] Now, specific operations of the substrate processing system
1 will be discussed with reference to FIG. 8. FIG. 8 is a flowchart
showing a process sequence of processing the substrate in
accordance with the first example embodiment. Respective processes
shown in FIG. 8 are performed under the control of the first
control device 4A or the second control device 4B.
[0132] In the substrate processing system 1 in accordance with the
first example embodiment, processes from a dry etching process
(block S101) to a first unloading process (block S107) shown in
FIG. 8 are performed in the first processing apparatus 2, and
processes from a removing liquid supplying process (block S108) to
a second unloading process (block S110) are performed in the second
processing apparatus 3.
[0133] As shown in FIG. 8, at block S101 (Dry Etching Process), the
dry etching process is performed in the dry etching unit. In this
dry etching process, the dry etching unit 12 performs a dry etching
or ashing on a wafer W. As a result, a Cu wiring 102 formed within
the wafer W is exposed (see FIG. 1A).
[0134] Then, the wafer W is loaded into the first liquid processing
unit 14. Since this loading process is performed through the load
lock chamber 13, the exposed Cu wiring 102 can be suppressed from
being oxidized. Processing may proceed from block S101 to block
S102.
[0135] Subsequently, at block S102 (Chemical Liquid Process), a
chemical liquid process is performed in the first liquid processing
unit 14. In this chemical liquid process, the nozzle 41a of the
liquid supply unit 40_1 (see FIG. 6) is positioned above a central
portion of the wafer W, and a DHF is supplied onto the wafer W from
the nozzle 41a. The DHF supplied to the wafer W is diffused on a
main surface of the wafer W by a centrifugal force generated by
rotation of the wafer W.
[0136] Accordingly, a surface of a reaction product P or the Cu
wiring 102 is slightly dissolved by the DHF, and an adhesive
strength of the reaction product P is weakened. Thus, the reaction
product P becomes easily removable.
[0137] Here, the chemical liquid process of block S102 is performed
to easily remove the reaction product P, and is performed under a
low etching condition where the reaction product P may not be
completely removed. Here, the term "low etching condition" means a
condition for performing etching with, for example, an etching time
shorter than an etching time required to completely remove the
reaction product P, or a DHF concentration lower than a DHF
concentration required to completely remove the reaction product
P.
[0138] Thus, as compared to the conventional case of removing the
reaction product P only with the DHF, it is possible to remove the
reaction product P more effectively while suppressing the Cu wiring
102 from being damaged. Further, since the DHF supplied from the
nozzle 41a in the first example embodiment is diluted to a preset
concentration that does not incur corrosion of the Cu wiring 102,
damage on the Cu wiring 102 may be more securely suppressed.
[0139] A reaction product P having a relatively smaller particle
size may be easily removed in the chemical liquid process, whereas
a reaction product P having a relatively larger particle size may
be easily removed in a removing process using a topcoat liquid and
an alkali removing liquid to be described later. Accordingly,
through the combination of these two types of processes, it is
possible to remove the reaction product P more effectively.
[0140] The chemical liquid supplied from the nozzle 41a may not be
limited to the DHF. By way of non-limiting example, ammonium
fluoride, hydrochloric acid, sulfuric acid, hydrogen peroxide
water, phosphoric acid, acetic acid, nitric acid, ammonium
hydroxide, organic acid, an aqueous liquid containing ammonium
fluoride, or the like may be used as the chemical liquid.
Processing may proceed from block S102 to block S103.
[0141] Subsequently, in the first liquid processing unit 14, at
block S103 (Rinsing Process), a rinsing process of cleaning the
main surface of the wafer W with DIW is performed. In this rinsing
process, the nozzle 41b (see FIG. 6) is positioned above the
central portion of the wafer W. Thereafter, the valve 44b is opened
for a preset time, so that the DIW is supplied from the nozzle 41b
onto the main surface of the wafer W being rotated, and the DHF
remaining on the wafer W is washed away. Processing may proceed
from block S103 to block S104.
[0142] Thereafter, at block S104 (Substitution Process), a
substitution process is performed in the first liquid processing
unit 14. In this substitution process, the nozzle 41c (see FIG. 6)
is positioned above the central portion of the wafer W. Then, the
valve 44c is opened for a preset time, so that IPA is supplied from
the nozzle 41c onto the main surface of the wafer W being rotated,
and the DIW on the wafer W is substituted with the IPA. Then, the
rotation of the wafer W is stopped while the IPA remains on the
wafer W. Upon the completion of the substitution process, the
liquid supply unit 40_1 is moved to the outside of the wafer W. The
processes from blocks S102 to S104 may not necessarily be
performed. Processing may proceed from block S104 to block
S105.
[0143] Subsequently, at block S105 (Solvent Supplying Process), a
solvent supplying process is performed in the first liquid
processing unit 14. The solvent supplying process is a process of
supplying MIBC having affinity with the topcoat liquid onto the
wafer W before supplying the topcoat liquid as a film forming
liquid onto the wafer W.
[0144] To elaborate, the nozzle 41d of the liquid supply unit 40_2
is positioned above the central portion of the wafer W. Then, the
MIBC is supplied onto the wafer W from the nozzle 41d. The MIBC
supplied on the wafer W is diffused on the main surface of the
wafer W by the centrifugal force generated by the rotation of the
wafer W.
[0145] In this way, by diffusing the MIBC having affinity with the
topcoat liquid on the wafer W in advance, the topcoat liquid may be
easily diffused on the wafer W and easily enter the via hole 106 in
a subsequent film forming liquid supplying process to be described
later. Accordingly, a consumption amount of the topcoat liquid can
be decreased, and the reaction product P within the via hole 106
can be more securely removed.
[0146] The MIBC has high affinity with the topcoat liquid, whereas
the MIBC is hardly mixed with DIW and has low affinity with the
DIW. Thus, in the first liquid processing unit 14, prior to
supplying the MIBC, the DIW is substituted with the IPA having
higher affinity with the MIBC than the DIW. Accordingly, as
compared to a case of performing the solvent supplying process
(block S105) immediately after the rinsing process (block S103),
the MIBC is allowed to be more easily diffused on the main surface
of the wafer W. Therefore, a consumption amount of the MIBC can be
decreased.
[0147] Further, in case that a solvent having affinity with the
film forming liquid has affinity with the DIW as well, the
substitution process of block S104 may be omitted.
[0148] As stated above, it is desirable to perform the
above-described solvent supplying process, for example, to diffuse
the topcoat liquid on the top surface of the wafer W efficiently
for a short time period. Further, if the film forming liquid has
affinity with the IPA, the solvent supplying process of block S105
may be omitted. Processing may proceed from block S105 to block
S106.
[0149] Thereafter, at block S106 (Film Forming Liquid Supplying
Process), the film forming liquid supplying process is performed in
the first liquid processing unit 14. In this film forming liquid
supplying process, the nozzle 41e of the liquid supply unit 40_2 is
positioned above the central portion of the wafer W. Then, the
topcoat liquid as a film forming liquid is supplied from the nozzle
41e onto the main surface of the wafer W, which serves as a surface
on which a circuit is formed and no resist film is formed.
[0150] The topcoat liquid supplied on the wafer W is diffused on
the main surface of the wafer W by the centrifugal force generated
by the rotation of the wafer W. As a result, a liquid film of the
topcoat liquid is formed on the entire main surface of the wafer W
(see FIG. 1B). At this time, the wettability of the main surface of
the wafer W has been increased by supplying the MIBC on the wafer W
at block S105. Thus, the topcoat liquid can be easily diffused on
the main surface of the wafer W, and can enter the via hole 106
more easily. Therefore, the consumption amount of the topcoat
liquid can be reduced, and a processing time can also be
shortened.
[0151] As a volatile component is volatilized when the wafer W is
rotated, the topcoat liquid is solidified or cured. As a result, a
topcoat film is formed on the entire main surface of the wafer
W.
[0152] Further, a volatilization accelerating process is performed
in the first liquid processing unit 14. This volatilization
accelerating process is a process of accelerating the
volatilization of the volatile component contained in the topcoat
liquid for forming the film on the entire main surface of the wafer
W. To be specific, by opening the valve 33 (see FIG. 6) for a
preset time, a high-temperature N.sub.2 gas is supplied from the
fluid supply unit 32 to the rear surface of the wafer W being
rotated. As a consequence, the topcoat liquid is heated along with
the wafer W, so that the volatilization of the volatile component
can be accelerated.
[0153] Alternatively, the volatilization accelerating process may
be a process of depressurizing the inside of the chamber 20 by a
non-illustrated depressurizing device or a process of decreasing
humidity within the chamber 20 by a gas supplied from the FFU 21.
The volatilization of the volatile component can also be
accelerated through these processes.
[0154] Here, though the present example embodiment is described for
the case of performing the volatilization accelerating process in
the first liquid processing unit 14, the volatilization
accelerating process may be omitted. That is, the wafer W may be
left in the first liquid processing unit 14 until the topcoat
liquid is naturally solidified or cured. Further, by rotating the
wafer W at a rotational speed that does not make the topcoat liquid
dispersed off the wafer W and does not expose the main surface of
the wafer W or does not stop the rotating of the wafer W, the
volatilization of the topcoat liquid may be accelerated. Processing
may proceed from block S106 to block S107.
[0155] Subsequently, at block S107 (First Unloading Process), a
first unloading process is performed in the first liquid processing
unit 14. In this first unloading process, the substrate transfer
device 111 takes out the wafer W from the first liquid processing
unit 14, and then, transfers the wafer W onto the mounting unit 10
to accommodate the wafer W in the carrier C mounted on the mounting
unit 10.
[0156] At this time, the exposed Cu wiring 102 of the wafer W is
covered with the topcoat liquid in a short time period after the
dry etching (see FIG. 1C). That is, since the Cu wiring 102 is
blocked from the exterior air, an adverse effect on the wafer W,
such as oxidation thereof, may be avoided.
[0157] Accordingly, in the substrate processing system 1 of the
first example embodiment, since time management for keeping the
Q-time from the end of the dry etching to the cleaning process
becomes unnecessary, productivity can be improved.
[0158] The wafer W accommodated in the carrier C is transferred
from the first processing apparatus 2 to the mounting unit 16 of
the second processing apparatus 3. Thereafter, the wafer W is taken
out of the carrier C by the substrate transfer device 171 (see FIG.
4) of the second processing apparatus 3, and then, loaded into the
second liquid processing unit 19 via the transit unit 172 and the
substrate transfer device 181. Processing may proceed from block
S107 to block S108.
[0159] In the second liquid processing unit 19, at block S108
(Removing Liquid Supplying Process), a removing liquid supplying
process is performed first. In the removing liquid supplying
process, the nozzle 81b (see FIG. 7) is positioned above the
central portion of the wafer W. Then, the valve 84b is opened for a
preset time, and the alkali developer as a removing liquid is
supplied from the nozzle 81b onto the wafer W being rotated. As a
result, the topcoat film formed on the wafer W is peeled off and
dissolved to be removed from the wafer W.
[0160] At this time, the reaction product P remaining on the wafer
W is peeled off and removed from the wafer W. At the moment, since
zeta potentials having the same polarity are generated on the wafer
W and the reaction product P, the wafer W and the reaction product
P are repelled against each other. Thus, re-attachment of the
reaction product P to the wafer W or the like can be
suppressed.
[0161] Further, the alkali developer contains an anticorrosive
material that suppresses corrosion of the Cu wiring 102.
Accordingly, corrosion of the Cu wiring 102 can be suppressed even
when the alkali developer is supplied on the Cu wiring 102. Thus,
in accordance with the substrate processing system 1 of the first
example embodiment, it is possible to remove the topcoat film while
suppressing the Cu wiring 102 from being damaged. Processing may
proceed from block S108 to block S109.
[0162] Subsequently, at block S109 (Chemical Liquid Process), a
chemical liquid process is performed in the second liquid
processing unit 19. In this chemical liquid process, the nozzle 81a
(see FIG. 7) is positioned at the central portion of the wafer W,
and the DHF is supplied onto the wafer W from the nozzle 81a. The
DHF supplied on the wafer W is diffused on the main surface of the
wafer W by the centrifugal force generated by the rotation of the
wafer W.
[0163] In this way, by performing the chemical liquid process after
the removing liquid supplying process, i.e., after removing the
topcoat film, it is possible to remove the reaction product P
(especially, a reaction product P having a relatively smaller
particle size), if any, which may still remain on the wafer W
without being removed when the topcoat film is peeled off. Even in
such a case, it is possible to remove the reaction product P more
effectively while suppressing damage on the wafer W, as compared to
a general chemical liquid cleaning process. Further, if the
reaction product P is removed sufficiently by the removing liquid
supplying process, the chemical liquid process of block S109, i.e.,
the wet cleaning process may be omitted.
[0164] Upon the completion of the chemical liquid process, there is
performed a rinsing process of cleaning the main surface of the
wafer W by supplying the DIW onto the wafer W from the nozzle 81c
in the second liquid processing unit 19. Through this rinsing
process, the dissolved topcoat film or the reaction product P
floating in the alkali developer are washed away by the DIW from
the wafer W. After the rinsing process, in the second liquid
processing unit 19, there is performed a drying process of drying
the wafer W by increasing the rotational speed of the wafer W for a
preset time period to disperse the DIW remaining on the main
surface of the wafer W. Thereafter, the rotation of the wafer W is
stopped. Processing may proceed from block S109 to block S110.
[0165] Then, at block S110 (Second Unloading Process), a second
unloading process is performed in the second liquid processing unit
19. In this second unloading process, the wafer W is unloaded from
the second liquid processing unit 19 by the substrate transfer
device 181 (see FIG. 4), and then, accommodated in the carrier C
mounted on the mounting unit 16 via the transit unit 172 and the
substrate transfer device 171. Upon the completion of the second
unloading process, a series of substrate processes on the single
sheet of wafer W is finished.
[0166] As described above, the substrate processing system 1 in
accordance with the first example embodiment includes the mounting
unit 10, the liquid supply unit 40_2 (corresponding to the example
processing liquid supply unit), and the substrate transfer device
111. The mounting unit 10 is configured to mount thereon carriers C
each of which is capable of accommodating therein a multiple number
of wafers W. The liquid supply unit 40_2 is configured to supply
the topcoat liquid, which contains a volatile component and is used
as a processing liquid for forming a film on the wafer W, after
performing the dry etching or ashing on the wafer W in which a Cu
wiring 102 is formed and at least a part thereof is exposed. The
substrate transfer device 111 transfers, to the mounting unit 10,
the wafer W having thereon the topcoat liquid solidified or cured
as a result of the volatilization of the volatile component, and
then accommodates the wafer W in the carrier C mounted on the
mounting unit 10.
[0167] Accordingly, in accordance with the substrate processing
system 1 of the first example embodiment, the Q-time from the
exposure of the Cu wiring 102 to the cleaning process is easily
managed, so that productivity may be improved.
Second Example Embodiment
[0168] Meanwhile, in a semiconductor manufacturing process, a rear
surface process such as cleaning on a rear surface of a wafer W may
be performed. In such a case, however, there is a concern that a
cleaning liquid used in the rear surface process may be dispersed
to or infiltrated into a main surface of the wafer W, so that the
main surface of the wafer W is contaminated.
[0169] Accordingly, by forming a topcoat film on the main surface
of the wafer W and then performing the rear surface process of the
wafer W in the state that the main surface of the wafer W is
protected by the topcoat film, the contamination of the main
surface of the wafer W may be suppressed.
[0170] This process will be described below with reference to FIG.
9A and FIG. 9B. FIG. 9B and FIG. 9B illustrate an example rear
surface cleaning process.
[0171] As illustrated in FIG. 9A, a fluid supply unit 32 included
in a first liquid processing unit 14A is connected to an N.sub.2
supply source 34 via a valve 33 and also connected to a SC1 supply
source 36 via a valve 35. The fluid supply unit 32 is configured to
supply an N.sub.2 gas introduced from the N.sub.2 supply source 34
to the rear surface of the wafer W and, also, supply SC1 (ammonia
hydrogen peroxide water) introduced from the SC1 supply source 36
to the rear surface of the wafer W.
[0172] The first liquid processing unit 14A is configured to
perform the rear surface cleaning process depicted in FIG. 9B after
the process of block S106 shown in FIG. 8 is performed, i.e., after
a topcoat film is formed on the entire main surface of the wafer
W.
[0173] In the rear surface cleaning process, the valve 35 is opened
for a preset time, and the SC1 is supplied from the fluid supply
unit 32 to the rear surface of the wafer W being rotated. As a
result, the rear surface of the wafer W is cleaned.
[0174] As described, in this second example embodiment, the rear
surface of the wafer W is cleaned in the state that the entire main
surface of the wafer W is covered with the topcoat film.
Accordingly, even if the cleaning liquid is dispersed during the
rear surface cleaning process, the dispersed cleaning liquid may be
suppressed from adhering to the main surface of the wafer W, so
that the contamination of the main surface of the wafer W can be
suppressed. Furthermore, contamination of the main surface of the
wafer W as a result of infiltration of the cleaning liquid may also
be suppressed.
[0175] Although FIG. 9A and FIG. 9B depict an example case of
performing the rear surface cleaning process by supplying the
cleaning liquid such as SC1 to the rear surface of the wafer W, the
rear surface cleaning process may not be limited thereto. For
example, a scrub cleaning using a cleaning member such as a brush
may be performed as the rear surface cleaning process.
[0176] An example case of performing the scrub cleaning as the rear
surface cleaning process will be described below with reference to
FIG. 10. FIG. 10 is a diagram illustrating such another example
rear surface cleaning process.
[0177] When performing the scrub cleaning as the rear surface
cleaning process, a first liquid processing unit 14B shown in FIG.
10 first carries out processes of blocks S101 to S106 shown in FIG.
8.
[0178] Subsequently, the wafer W is taken out of the first liquid
processing unit 14B by the substrate transfer device 111, and then,
transferred to a non-illustrated inverting device. After front and
rear surfaces of the wafer W are inverted by the inverting device,
the wafer W is loaded again into the first liquid processing unit
14B by the substrate transfer device 111. By way of example, the
inverting device may be provided in the processing station 6 of the
first processing apparatus 2. As for the inverting device, any of
various known configurations may be employed.
[0179] Subsequently, as illustrated in FIG. 10, the first liquid
processing unit 14B holds and rotates the inverted wafer W by a
substrate holding device 30 and, then, performs the scrub cleaning
on the rear surface of the wafer W by using a brush 500.
Specifically, by moving the rotating brush 500 while maintaining
the brush 500 in contact with the rear surface of the wafer W, the
first liquid processing unit 14B removes foreign substances
adhering to the wafer W.
[0180] At this time, since the entire main surface of the wafer W
is covered with the topcoat film, the foreign substances removed
from the rear surface of the wafer W may not be attached to the
main surface of the wafer W. Here, a fluid such as an N.sub.2 gas
from the fluid supply unit 32 may be supplied, so that the foreign
substances can be suppressed from adhering to the topcoat film.
[0181] Upon the completion of the scrub cleaning, the wafer W is
unloaded from the first liquid processing unit 14B by the substrate
transfer device 111, inverted again by the non-illustrated
inverting device, and then, accommodated in the carrier C.
[0182] Here, although the brush 500 is used, the scrub cleaning may
be performed by using other cleaning members such as a sponge.
[0183] In addition, a process of jetting a gas cluster to the rear
surface of the wafer W to remove particles from the rear surface of
the wafer W may be performed as the rear surface cleaning process.
This process will be described below with reference to FIG. 11.
FIG. 11 illustrates such a still another example rear surface
cleaning process.
[0184] As illustrated in FIG. 11, a first liquid processing unit
14C includes a nozzle 600. The nozzle 600 is configured to jet
carbon dioxide as a cleaning gas at a high pressure and configured
to generate a gas cluster, which is an aggregate of atoms or
molecules of the cleaning gas, by adiabatic expansion.
[0185] The nozzle 600 includes a pressure chamber 601 formed in,
for example, a substantially cylindrical shape of which bottom
portion is opened. The bottom portion of the pressure chamber 601
is formed to have an orifice 602. A gas diffuser 603 of which
diameter increases downward is connected to the orifice 602. At the
orifice 602, an opening diameter is, e.g., about 0.1 mm.
[0186] One end of a gas supply path 604 is connected to a top
portion of the pressure chamber 601, and a carbon dioxide supply
source 606 is connected to the other end of the gas supply path 604
via a pressure control valve 605.
[0187] The first liquid processing unit 14C is configured to invert
the wafer W having the topcoat film formed thereon and, then,
rotate the wafer W while holding the wafer W on the substrate
holding device 30 in the same process sequence as that in the case
of performing the above-described scrub cleaning. Further, the
first liquid processing unit 14C is configured to supply carbon
dioxide to the nozzle 600 at a higher pressure than a pressure
within the chamber 20 of the first liquid processing unit 14C. Once
jetted from the nozzle 600 into the chamber 20, the carbon dioxide
is cooled to be a temperature equal to or lower than a condensation
temperature by rapid adiabatic expansion, and molecules M1 thereof
are agglomerated together into gas clusters M2, which are the
aggregates, by a van der Waals force.
[0188] The gas clusters M2 are vertically jetted toward the rear
surface of the wafer W, and may blow away and remove foreign
substances attached on the rear surface of the wafer W. Here, the
entire main surface of the wafer W is covered with the topcoat
film. Accordingly, the foreign substances removed from the rear
surface of the wafer W may be suppressed from adhering to the main
surface of the wafer W.
[0189] After the cleaning by the gas clusters M2 is completed, the
wafer W is unloaded from the first liquid processing unit 14C by
the substrate transfer device 111, inverted once again by the
non-illustrated inverting device, and, then, accommodated in the
carrier C.
[0190] Alternatively, the rear surface cleaning process may be
implemented by a two-fluid cleaning process using a two-fluid
nozzle configured to jet a cleaning liquid to the rear surface of
the wafer W in a mist form by a gas, an ultrasonic cleaning process
using an ultrasonic oscillator, or the like.
[0191] In addition, the process performed in the state that the
main surface of the wafer W is covered with the topcoat film may
not be limited to the rear surface cleaning process, and may be, by
way of example, an etching process of etching a rear surface or a
bevel of the wafer W by using a chemical liquid. Here, the etching
process may be a process of removing an oxide film by using, for
example, hydrofluoric acid (HF) or the like. Since the etching
process is performed in the state that the main surface of the
wafer W is covered with the topcoat film, the main surface of the
wafer W may not be etched by being protected by the topcoat film
even if the chemical liquid infiltrates from the rear surface of
the wafer W toward the main surface thereof. As described, since an
area to be etched is determined by the topcoat film, the etching
process can be performed with high accuracy.
[0192] In addition, the process performed in the state that the
main surface of the wafer W is covered with the topcoat film may
also be a polishing process of polishing the rear surface or the
bevel of the wafer W by using a polishing brush.
[0193] As stated above, by processing the other surface of the
wafer W in the state that the main surface of the wafer W is
covered with the topcoat film, the other surface of the wafer W can
be processed while suppressing the main surface of the wafer W from
being contaminated.
[0194] The above second example embodiment has been described for
the case where each of the first liquid processing units 14A to 14C
corresponds to an example other surface processing unit. That is,
the second example embodiment has been described for the case where
the first liquid processing units 14A to 14C perform the rear
surface cleaning process as well as a film forming liquid supplying
process. However, the first processing apparatus 2 may additionally
include a rear surface cleaning unit configured to perform the rear
surface cleaning process, separately from the first liquid
processing unit 14.
[0195] In addition, the other surface process such as the rear
surface cleaning process may be performed in the second processing
apparatus 3. In this case, a nozzle or a brush for the rear surface
cleaning may be provided in the second liquid processing unit 19,
or a rear surface processing unit, which is separate from the
second liquid processing unit 19, may be additionally provided in
the second processing apparatus 3.
Third Example Embodiment
[0196] Further, the configurations for performing the film forming
liquid supplying process or the removing liquid supplying process
may be additionally provided in a conventional pre-treatment or
post-treatment apparatus which does not have these configurations.
In a third example embodiment, such a configuration will be
described. FIG. 12 is a diagram depicting a schematic configuration
of a first processing apparatus in accordance with the third
example embodiment.
[0197] As illustrated in FIG. 12, the first processing apparatus 2A
includes a first block 2A1, a second block 2A2, and a connecting
unit 2A3.
[0198] The first block 2A1 includes a loading/unloading station 5
and a processing station 6. Since the loading/unloading station 5
is the same as the aforementioned loading/unloading station 5 of
the first processing apparatus 2 in accordance with the first
example embodiment, specific elaboration thereof is omitted
herein.
[0199] A multiple number of dry etching units 12 are arranged in
the processing station 6 of the first block 2A1. In addition,
unlike the processing station 6 of the first processing apparatus 2
in the first example embodiment, the processing station 6 of the
first block 2A1 does not include the first liquid processing unit
14.
[0200] The second block 2A2 includes a transfer unit 11' and a
multiple number of first liquid processing units 14. The transfer
unit 11' includes a substrate transfer device 112, which is the
same as the substrate transfer device 111, and performs the
loading/unloading of a wafer W into/from the first liquid
processing units 14 by using the substrate transfer device 112.
[0201] The connecting unit 2A3 is configured to connect the
transfer unit 11 of the first block 2A1 and the transfer unit 11'
of the second block 2A2 to each other. This connecting unit 2A3 has
an internal space blocked from the atmosphere. The internal space
is filled with an inert gas such as an N.sub.2 gas and blocked from
the atmosphere. Further, a non-illustrated mounting table is
provided in the internal space.
[0202] In this first processing apparatus 2A, after a process in a
dry etching unit 12 is finished, the wafer W is taken out of the
dry etching unit 12 by the substrate transfer device 111, and,
then, mounted on the non-illustrated mounting table of the
connecting unit 2A3.
[0203] The wafer W mounted on the mounting table is taken out of
the mounting table by the substrate transfer device 112 of the
second block 2A2, and then, transferred into a corresponding first
liquid processing unit 14 in which the processes of blocks S102 to
S106 shown in FIG. 8 are performed. As a result, a topcoat film is
formed on a main surface of the wafer W.
[0204] Thereafter, the wafer W is taken out of the first liquid
processing unit 14 by the substrate transfer device 112,
transferred from the substrate transfer device 112 to the substrate
transfer device 111 via the non-illustrated mounting table of the
connecting unit 2A3, and, then, accommodated in the carrier C
mounted on the mounting unit 10 by the substrate transfer device
111.
[0205] As described, the first liquid processing unit 14 configured
to perform a film forming liquid supplying process may be provided
separately from the first block 2A1 including the mounting unit 10,
the substrate transfer device 111 and the dry etching unit 12, and
the first liquid processing unit 14 may be provided in the second
block 2A2 connected to the first block 2A1 via the connecting unit
2A3. That is, the first liquid processing unit 14 may be
additionally provided in the conventional pre-treatment apparatus
which does not have the first liquid processing unit 14.
[0206] In this case, by blocking the internal space of the
connecting unit 2A3 from the atmosphere, the Cu wiring 102 exposed
by the dry etching can be suppressed from being oxidized when the
wafer W is transferred from the first block 2A1 to the second block
2A2 after the dry etching.
[0207] In addition, like the internal space of the connecting unit
2A3, the inside of the transfer unit 11 of the first block 2A1 and
the inside of the transfer unit 11' of the second block 2A2 may
also be filled with an N.sub.2 gas or the like, and thus, blocked
from the atmosphere. In this configuration, the exposed Cu wiring
102 can be further suppressed from being oxidized.
[0208] In addition, in the above-described third example
embodiment, the transfer unit 11 of the first block 2A1 and the
transfer unit 11' of the second block 2A2 are connected to each
other by the connecting unit 2A3. However, the first processing
apparatus 2A may have, for example, a configuration in which the
dry etching unit 12 of the first block 2A1 and the first liquid
processing unit 14 of the second block 2A2 are connected to each
other by the connecting unit 2A3. In such a configuration, a
non-illustrated substrate transfer device may be provided in the
internal space of the connecting unit 2A3, and the wafer W may be
transferred between the dry etching unit 12 and the first liquid
processing unit 14 by the non-illustrated substrate transfer
device. In addition, in this configuration, the second block 2A2
does not need to include the transfer unit 11'.
[0209] Now, a modification example of the second processing
apparatus will be described with reference to FIG. 13. FIG. 13 is a
diagram depicting a schematic configuration of a second processing
apparatus in accordance with the third example embodiment.
[0210] As depicted in FIG. 13, the second processing apparatus 3A
includes a first block 3A1, a second block 3A2, and a connecting
unit 3A3.
[0211] The first block 3A1 includes a loading/unloading station 7
and a processing station 8. The loading/unloading station 7 is the
same as the loading/unloading station 7 of the second processing
apparatus 3 in accordance with the first example embodiment.
[0212] A multiple number of second liquid processing units 19A are
arranged in the processing station 8 of the first block 3A1. Each
second liquid processing unit 19A has the same configuration as
that of each second liquid processing unit 19 of the first example
embodiment excepting that the components related to a removing
liquid supplying process, specifically, the nozzle 81b, the valve
84b and the alkali developer supply source 85b are omitted in the
second liquid processing unit 19A.
[0213] The second block 3A2 includes a transfer unit 18' and a
multiple number of removing units 700. The transfer unit 18'
includes a substrate transfer device 182, which is the same as the
substrate transfer device 181. Loading/unloading of the wafer W
into/from the removing units 700 are performed by using the
substrate transfer device 182.
[0214] The removing units 700 have the configuration excluding the
nozzle 81a, the valve 84a, the DHF supply source 85a, the nozzle
81c, the valve 84c and the DIW supply source 85c, from the second
liquid processing units 19 in accordance with the first example
embodiment.
[0215] The connecting unit 3A3 connects the transfer unit 18 of the
first block 3A1 and the transfer unit 18' of the second block 3A2
to each other. This connecting unit 3A3 has an internal space
blocked from the atmosphere. The internal space is blocked from the
atmosphere by being filled with an inert gas such as, but not
limited to, an N.sub.2 gas. In addition, a non-illustrated mounting
table is provided in the internal space.
[0216] In this second processing apparatus 3A, the wafer W is
transferred from the loading/unloading station 7 to the transfer
unit 18 of the processing station 8, and, then, mounted on the
non-illustrated mounting table of the connecting unit 3A3 by the
substrate transfer device 181.
[0217] The wafer W mounted on the mounting table is taken out of
the mounting table by the substrate transfer device 182 of the
second block 3A2, and, then, transferred to a corresponding
removing unit 700 in which the removing liquid supplying process
(block S108 of FIG. 8) is performed. As a result, the topcoat film
is removed from the main surface of the wafer W.
[0218] Thereafter, the wafer W is taken out of the removing unit
700 by the substrate transfer device 182, and, then, transferred
from the substrate transfer device 182 to the substrate transfer
device 181 via the non-illustrated mounting table of the connecting
unit 3A3. Then, the wafer W is transferred into a corresponding
second liquid processing unit 19A by the substrate transfer device
181. After the chemical liquid process (block S109 of FIG. 8) is
performed by the second liquid processing unit 19A, the wafer W is
accommodated back into the carrier C through the second unloading
process (block S110 of FIG. 8).
[0219] As stated above, the removing unit 700 configured to perform
the removing liquid supplying process may be provided separately
from the first block 3A1 including the mounting unit 16, the
substrate transfer device 181 and the second liquid processing
units 19A configured to perform the chemical liquid process. The
removing unit 700 may be provided in the second block 3A2 connected
to the first block 3A1 via the connecting unit 3A3. That is, the
removing unit 700 may be additionally provided in the conventional
post-treatment apparatus which does not have the removing unit
700.
[0220] In such a configuration, by blocking the internal space of
the connecting unit 3A3 from the atmosphere, the exposed Cu wiring
102 can be suppressed from being oxidized when transferring the
wafer W from the second block 3A2 to the first block 3A1 after the
removing process. In addition, in the second processing apparatus
3A, the inside of the transfer unit 18 of the first block 3A1 and
the inside of the transfer unit 18' of the second block 3A2 may
also be blocked from the atmosphere.
[0221] In addition, the second block 3A2 may include the same
loading/unloading station as the loading/unloading station 7. In
this configuration, the wafer W having the topcoat film formed
thereon is loaded from the loading/unloading station of the second
block 3A2 into the inside of the second block 3A2, and the topcoat
film is removed from the wafer W by the removing unit 700. Then,
the wafer W is transferred into the first block 3A1 via the
connecting unit 3A3. Thus, transfer efficiency of the wafer W can
be improved.
Fourth Example Embodiment
[0222] The above example embodiments have been described for an
example case of removing the topcoat film from the wafer W by
supplying the alkali developer as a removing liquid to the topcoat
film. However, the process of removing the topcoat film from the
wafer W may not be limited to the above-described examples.
Hereinafter, another example removing process of removing the
topcoat film from the wafer W will be elaborated. FIG. 14 is a
diagram illustrating a schematic configuration of a second
processing apparatus in accordance with a fourth example
embodiment.
[0223] As illustrated in FIG. 14, a second processing apparatus 3B
in accordance with the fourth example embodiment includes, in a
processing station 8, a multiple number of second liquid processing
units 19B and a multiple number of removing units 710.
[0224] Each of the second liquid processing units 19B has the same
configuration as that of the second liquid processing unit 19A in
the third example embodiment. That is, the second liquid processing
unit 19B has the same configuration as that of the second liquid
processing unit 19 of the first example embodiment excepting that
the components related to a removing liquid supplying process,
i.e., the nozzle 81b, the valve 84b and the alkali developer supply
source 85b are omitted in the second liquid processing unit
19B.
[0225] Each of the removing units 710 is configured to remove a
film formed on a wafer W by sublimation. Here, a configuration of
the removing unit 710 will be described with reference to FIG. 15.
FIG. 15 is a schematic diagram illustrating an example
configuration of the removing unit 710 in accordance with the
fourth example embodiment.
[0226] In the fourth example embodiment, a liquid of a sublimation
material is used as the film forming liquid. By way of non-limiting
example, ammonium fluorosilicate, camphor, naphthalene or the like
may be used as the sublimation material. The film forming liquid is
obtained by dissolving the sublimation material in a volatile
solvent such as IPA. Such a film forming liquid is solidified or
cured into a film as a result of volatilization of IPA serving as
the solvent. The film forming liquid may include pure water besides
the sublimation material and the IPA.
[0227] As illustrated in FIG. 15, the removing unit 710 includes a
hot plate 701 having a heater 702 embedded therein, and a multiple
number of support pins 703 protruded from a top surface of the hot
plate 701. The support pins 703 support a peripheral portion of a
rear surface of a wafer W. Accordingly, a small gap is formed
between the rear surface of the wafer W and the top surface of the
hot plate 701.
[0228] Above the hot plate 701, there is provided an exhaust hood
704, which is configured to be moved up and down. The exhaust hood
704 has an opening at a central portion thereof. An exhaust line
705, at which a sublimation material collecting device 706 and a
pump 707 are provided, is connected to the opening of the hot plate
701. Here, as the sublimation material collecting device 706, there
may be employed various commonly known sublimation material
collecting devices, such as a device in which a sublimation
material is precipitated on a cooling plate provided within a
chamber through which an exhaust gas flows, or a device in which a
cooling fluid is contacted with a gas of a sublimation material
within a chamber through which an exhaust gas flows.
[0229] If a wafer W is mounted on the support pins 703 by the
substrate transfer device 181, the removing unit 710 lowers the
exhaust hood 704 to form a processing space between the exhaust
hood 704 and the hot plate 701. Subsequently, while exhausting the
space above the wafer W by the pump 707 provided on the exhaust
line 705 connected to the exhaust hood 704, the removing unit 710
heats the wafer W to a temperature higher than a sublimation
temperature of the sublimation material by the temperature-raised
hot plate 701.
[0230] As a result, the sublimation material on the wafer W is
sublimated and removed from the wafer W. At this time, the
sublimation material, which has been sublimated and tuned into a
gas, is collected by the sublimation material collecting device 706
to be reused. Thereafter, the wafer W is taken out of the removing
unit 710 and transferred into the second liquid processing unit 19B
by the substrate transfer device 181.
[0231] As described above, the second processing apparatus 3B may
perform the removing process of removing the solidified or cured
film forming liquid from the wafer W by heating the wafer W to a
higher temperature than the sublimation temperature of the
sublimation material contained in the film forming liquid. Further,
the sublimation process adopted therein is nothing more than an
example, and there may be employed a process of directly
overheating the sublimation material itself, and not the substrate,
by a gas or the like. Further, the heating process may not be
performed, depending on a sublimation temperature of the
sublimation material.
Fifth Example Embodiment
[0232] The above example embodiments have been described for the
case of performing the chemical liquid process as a post-treatment
after removing the solidified or cured film forming liquid from the
wafer W. However, the post-treatment may not be limited to the
chemical liquid process. In a fifth example embodiment, an example
of performing a dry etching process as the post-treatment will be
described with reference to FIG. 16. FIG. 16 is a diagram depicting
a schematic configuration of a second processing apparatus in
accordance with the fifth example embodiment.
[0233] As illustrated in FIG. 16, a second processing apparatus 3C
in accordance with the fifth example embodiment includes, in a
processing station 8, a multiple number of removing units 720 and a
multiple number of dry etching units 800.
[0234] Each of the removing units 720 has the same configuration as
that of the removing unit 710 of the fourth example embodiment and
is configured to remove a solidified or cured film forming liquid
from a wafer W through sublimation. Alternatively, the removing
unit 720 may have the same configuration as that of the removing
unit 700 of the third example embodiment and may be configured to
remove the solidified or cured film forming liquid from the wafer W
by using a removing liquid such as an alkali developer.
[0235] Each of the dry etching units 800 has the same configuration
as that of the dry etching unit 12 of the first example embodiment
and is configured to perform a dry etching process on the wafer W
from which the solidified or cured film forming liquid has been
removed by the removing unit 720. Upon the completion of the dry
etching process, the wafer W is accommodated in the carrier C
through the second unloading process (block S110 of FIG. 8).
[0236] As stated above, the second processing apparatus 3C may
implement the dry etching process as the post-treatment. That is,
it is also possible to apply the above-described film forming
liquid supplying process and removing process to a process in which
a dry etching is performed as a pre-treatment and then further
performed as a post-treatment once more.
[0237] As one example of such a process, a hard mask etching of
etching a hard mask may be performed as a pre-treatment, and, then,
a main etching of etching a target film on the wafer W may be
performed as a post-treatment. By applying the above-described film
forming liquid supplying process and removing process to this
process, it is possible to suppress a reaction product P from
growing after the hard mask etching or to stabilize a profile of
the target film when performing the main etching.
[0238] In case of performing the removing process by sublimation as
described in the fourth example embodiment, it is also possible to
perform the removing process within the dry etching unit 800.
Sixth Example Embodiment
[0239] The above example embodiments have been described for the
case of applying the film forming liquid supplying process of
supplying the film forming liquid to the wafer W after the
pre-treatment and the removing process of removing the solidified
or cured film forming liquid from the wafer W to the process in
which the dry etching is performed as the pre-treatment and the
chemical liquid process or the dry etching process are performed as
the post-treatment. However, the application of the film forming
liquid supplying process and the removing process may not be
limited to the above example, and the film forming liquid supplying
process and the removing process as described above may also be
applicable to various processes performed in FEOL (Front End Of
Line), MEOL (Middle End Of Line) and BEOL (Back End Of Line).
[0240] Accordingly, in this sixth example embodiment, various
processes to which the film forming liquid supplying process and
the removing process are applied will be described with reference
to FIG. 17. FIG. 17 is a table showing example processes to which
the film forming liquid supplying process and the removing process
are applied.
[0241] The film forming liquid supplying process and the removing
process are applicable to a process which requires atmosphere
management or time management for a wafer W on which a
pre-treatment is performed. Here, the term "atmosphere management"
means, for example, controlling an atmosphere surrounding the wafer
W after the pre-treatment to be an inert gas atmosphere. Further,
the term "time management" means the Q-time management, which
delimits and manages the time from a pre-treatment to a
post-treatment.
[0242] That is, the process to which the film forming liquid
supplying process and the removing process are applied is a process
in which the atmosphere management or the time management described
above is required since a portion of a surface of a wafer W is
modified by being exposed to the atmosphere after being subject to
a pre-treatment. By applying the film forming liquid supplying
process and the removing process to this process, the portion to be
modified by being exposed to the atmosphere can be covered with the
solidified or cured film forming liquid and blocked from the
atmosphere. Thus, the atmosphere management and the time management
after the pre-treatment may become unnecessary.
[0243] As shown in FIG. 17, as an example of the process to which
the film forming liquid supplying process and the removing process
are applicable, there is a process of performing wet-cleaning
(post-treatment) after the dry etching (pre-treatment). An example
of this process may be a process described in the first example
embodiment, i.e., a process of post-cleaning a wafer W by a
chemical liquid after exposing a metal layer (which is not limited
to Cu but includes Co (cobalt), W (tungsten), or the like) within a
wafer W through the dry etching. Further, examples of this process
may be a process of post-cleaning a wafer W by a chemical liquid
after patterning Si, SiO.sub.2, SiN, a poly silicon gate electrode,
a HKMG (High-k/Metal Gate), or the like through the dry etching; a
process of post-cleaning a wafer W by a chemical liquid after
forming a contact hole through the dry etching; and so forth. By
applying the film forming liquid supplying process and the removing
process to these processes, it is possible to suppress the reaction
products from growing after the pre-treatment, for example. As for
the pre-treatment, the ashing as well as the dry etching may also
be employed, and even in case of performing the ashing as the
pre-treatment, it is still possible to apply the film forming
liquid supplying process and the removing process.
[0244] In addition, as another example of a process to which the
film forming liquid supplying process and the removing process are
applicable, there is a process of performing the dry etching
(post-treatment) after the dry etching (pre-treatment). Such a
process may be, for example, a process as described in the fifth
example embodiment. In this case as well, by applying the film
forming liquid supplying process and the removing process, the
reaction products after the pre-treatment can be suppressed from
growing.
[0245] As yet another example of a process to which the film
forming liquid supplying process and the removing process are
applicable, there is a process of performing film formation
(post-treatment) after film formation (pre-treatment). Examples of
such a process may include, but not limited to, a process of
forming a W layer on a wafer W after forming a TiN layer on the
wafer W, forming a Cu layer on a wafer W after forming a TaN layer
on the wafer W, and so forth.
[0246] Here, among the film forming apparatuses configured to
perform the film forming processes, the film forming apparatus for
the pre-treatment is arranged in the processing station of the
first processing apparatus, whereas the film forming apparatus for
the post-treatment is arranged in the processing station of the
second processing apparatus. As the film forming apparatus, a
plasma CVD apparatus may be used, but not limited thereto and
various commonly known techniques can be performed.
[0247] In addition, in case that a plasma CVD apparatus is used as
a film forming apparatus for the post-treatment and the removing
process is performed by sublimation as described in the fourth
example embodiment, it is possible to perform the removing process
within the plasma CVD apparatus. Further, in case that a film
forming apparatus configured to perform the film formation by the
wet process is used as the film forming apparatus for the
pre-treatment, it is possible to perform the film forming liquid
supplying process within that film forming apparatus.
[0248] As still another example process to which the film forming
liquid supplying process and the removing process are applicable,
there is a process of performing the film formation
(post-treatment) after the wet cleaning (pre-treatment). This
process may be, for example, a process of forming a metal film such
as a barrier metal on a wafer W after removing an oxide film or
foreign substances such as particles from the wafer W by
pre-cleaning the wafer W with a chemical liquid. By applying the
film forming liquid supplying process and the removing process to
such a process, it is possible to suppress the formed metal film
from being oxidized or the particles from being attached onto the
wafer W, for example.
[0249] In case of applying the film forming liquid supplying
process and the removing process to a process in which the wet
cleaning is performed as a pre-treatment, it is desirable to
perform the removing process by sublimation as described in the
fourth example embodiment.
[0250] That is, by performing the film forming liquid supplying
process after the wet cleaning to form a film of the film forming
liquid on the wafer W, a pattern collapse in the drying process can
be suppressed. In addition, by removing the film of the film
forming liquid through sublimation in the removing process, it is
possible to remove the film of the film forming liquid from the
wafer W without causing the pattern collapse.
[0251] The process of performing the other surface process as
described in the second example embodiment, the configurations of
the first processing apparatus and the second processing apparatus
as described in the third example embodiment, and the removing
process by sublimation as described in the fourth example
embodiment may be appropriately applied to each of the processes
specified in FIG. 17.
Other Example Embodiments
[0252] The foregoing example embodiments have been described for
the case of using a topcoat liquid or a sublimation material liquid
as a film forming liquid. However, the film forming liquid may not
be limited to these examples.
[0253] By way of non-limiting example, the film forming liquid may
be a processing liquid including a phenolic resin. Since the
phenolic resin is also subject to curing and shrinkage like the
above-described acrylic resin, using the phenolic resin may be
effective in applying a tensile force to a reaction product P, like
the topcoat liquid.
[0254] The film forming liquid including the phenolic resin may be,
for example, a resist liquid. The resist liquid is a film forming
liquid for forming a resist film on a wafer W. Specifically, the
resist liquid includes a novolac resin.
[0255] If the resist liquid is used as the film forming liquid, a
thinner capable of dissolving the resist liquid may be used as the
removing liquid. When using the thinner as the removing liquid, it
is possible to skip a rinsing process after a removing liquid
supplying process. Further, when using the resist liquid used as
the film forming liquid, the removing liquid may be supplied after
performing an exposure process of exposing, for example, the entire
surface of the resist film formed on the wafer W. In this case, the
removing liquid may be a developer or a thinner.
[0256] A synthetic resin contained in the film forming liquid is
not limited to the acrylic resin or the phenolic resin, and may not
be particularly limited as long as it is subject to cure shrinkage.
For example, the synthetic resin included in the film forming
liquid may be an epoxy resin, a melanin resin, an urea resin, an
unsaturated polyester resin, an alkyd resin, polyurethane,
polyimide, polyethylene, polypropylene, polyvinylchloride,
polystyrene, poly vinylacetate, polytetra fluoroethylene, an
acrylonitrile butadiene styrene resin, an acrylonitrile styrene
resin, polyamide, nylon, polyacetal, polycarbonate, modified
polyphenylene ether, polybutylene terephthalate, polyethylene
terephthalate, polyphenylene sulfide, polysulfon, polyether ether
ketone, polyamide amide, and so forth.
[0257] In addition, an anti-reflection film liquid may be used as
the film forming liquid. The anti-reflection film liquid is a film
forming liquid for forming an anti-reflection film on a wafer W.
Further, the anti-reflection film is also a protection film for
reducing surface reflection of the wafer W while increasing
transmittance. If such an anti-reflection film liquid is used as
the film forming liquid, the DIW capable of dissolving the
anti-reflection film liquid may be used as the removing liquid.
[0258] Further, the film forming liquid may further include a
certain chemical liquid, which dissolves a material formed on the
wafer W or foreign substances attached on the wafer W, in addition
to the volatile component and the synthetic resin. The "material
formed on the wafer W" may refer to, for example, the Cu wiring
102, and the "foreign substances attached on the wafer W" means,
for example, a reaction product P. In addition, the "certain
chemical liquid" may be, but not limited to, hydrogen fluoride,
ammonium fluoride, hydrochloric acid, sulfuric acid, hydrogen
peroxide water, phosphoric acid, acetic acid, nitric acid, ammonium
hydroxide, organic acid, or an aqueous liquid containing ammonium
fluoride. Since the adhesive strength of the reaction product P is
weakened as a surface of the reaction product P is dissolved by the
chemical liquid, the reaction product P may become easily
removable.
[0259] The "certain chemical liquid" is used under the condition of
a small etching amount, as compared to the chemical liquid used in
the general chemical liquid cleaning process in which the cleaning
is performed only by using a chemical operation of the chemical
liquid. Accordingly, it is possible to remove the reaction product
P more effectively, while suppressing erosion of the wafer W, as
compared to the case of the general chemical liquid cleaning
process.
[0260] Although the above-described example embodiments have been
described for the case of using the alkali developer as the
removing liquid, the removing liquid may be prepared by adding
hydrogen peroxide water to the alkali developer. By adding the
hydrogen peroxide water to the alkali developer, surface roughening
of the wafer W caused by the alkali developer may be
suppressed.
[0261] In addition, the removing liquid may be an organic solvent
such as a thinner, toluene, acetic acid esters, alcohols, and
glycols (propylene glycol monomethyl ether), or an acidic developer
such as acetic acid, formic acid, or hydroxy acetic acid.
[0262] In addition, the removing liquid may further include a
surfactant. Since the surfactant has a function to weaken a surface
tension, it can suppress re-attachment of a reaction product P to a
wafer W.
[0263] In addition, the above example embodiments have been
described for the case where the metal wiring formed within the
wafer W is the Cu wiring 102. However, the metal wiring is not
limited to the Cu wiring 102. In this regard, the removing liquid
for the topcoat film may contain an anticorrosive material
appropriately selected depending on the kind of the metal
wiring.
[0264] In addition, in the above-described example embodiments, a
target material of the dry etching is described to be a metal
wiring. However, the target material or structure to be etched by
the dry etching may not be limited to the metal wiring. Further,
the substrate processing method in accordance with the first
example embodiment may also be applied to a case of removing a
reaction product after a resist is removed by the ashing. For
example, the substrate processing method of the first example
embodiment may also be effective when being applied to a wafer
cleaning which is performed after injecting ions by using a resist
pattern as a mask and removing the resist by the ashing.
[0265] Furthermore, the above-described example embodiments have
been described for the case of performing the chemical liquid
process before the film forming liquid supplying process and, also,
after the removing liquid supplying process. However, the chemical
liquid process may be performed either before the film forming
liquid supplying process or after the removing liquid supplying
process. Moreover, the chemical liquid process may not necessarily
be performed.
[0266] In addition, in case of performing the chemical liquid
process after the removing liquid supplying process, the liquid
supply unit 40_1 included in the first liquid processing unit 14
may be provided in the second liquid processing unit 19, or a
separate processing unit configured to perform the chemical liquid
cleaning may be additionally provided.
[0267] Further, the configuration of the substrate processing
system 1 may not be limited to that described in the foregoing
example embodiments.
[0268] By way of example, the configuration of the liquid supply
unit 80 included in the second liquid processing unit 19 may be
provided in another film forming unit configured to perform a film
forming process on a wafer W having undergone the processes up to
block S107 of FIG. 8. That is, removing the topcoat film may be
performed in another film forming unit. Alternatively, a film
forming unit may be provided in the processing station 8 of the
second processing apparatus 3, and the film forming process may be
performed within the second liquid processing unit 19. In such a
case, since the film forming process can be performed immediately
after the topcoat film is removed, the Q-time management can be
further facilitated.
[0269] From the foregoing, it will be appreciated that various
embodiments of the present disclosure have been described herein
for purposes of illustration, and that various modifications may be
made without departing from the scope and spirit of the present
disclosure. Accordingly, the various embodiments disclosed herein
are not intended to be limiting, with the true scope and spirit
being indicated by the following claims.
* * * * *