U.S. patent application number 15/856486 was filed with the patent office on 2018-08-16 for substrate treating method and apparatus used therefor.
The applicant listed for this patent is SCREEN Holdings Co., Ltd.. Invention is credited to Yasuhiro FUKUMOTO, Takeharu ISHII, Tomohiro MATSUO, Yuji TANAKA.
Application Number | 20180231894 15/856486 |
Document ID | / |
Family ID | 63104601 |
Filed Date | 2018-08-16 |
United States Patent
Application |
20180231894 |
Kind Code |
A1 |
FUKUMOTO; Yasuhiro ; et
al. |
August 16, 2018 |
SUBSTRATE TREATING METHOD AND APPARATUS USED THEREFOR
Abstract
Disclosed is a substrate treating method for performing a heat
treatment of a substrate having a treated film formed thereon in a
heat treating space of a heat treating chamber. The method includes
an exhaust step of exhausting gas within the heat treating space
formed by a cover enclosing surroundings of a heat treating plate;
an inert gas supply step of supplying inert gas from an upper
portion of the heat treating space into the heat treating space and
supplying inert gas into a gap between an outer peripheral surface
of the heat treating plate and an inner wall of the cover; and a
heat treating step of performing the heat treatment of the
substrate in the heat treating space. The heat treating step is
performed after the exhaust step and the inert gas supply step.
Inventors: |
FUKUMOTO; Yasuhiro;
(Kyoto-shi, JP) ; TANAKA; Yuji; (Kyoto-shi,
JP) ; ISHII; Takeharu; (Kyoto-shi, JP) ;
MATSUO; Tomohiro; (Kyoto-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SCREEN Holdings Co., Ltd. |
Kyoto |
|
JP |
|
|
Family ID: |
63104601 |
Appl. No.: |
15/856486 |
Filed: |
December 28, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G03F 7/40 20130101; G03F
7/0002 20130101 |
International
Class: |
G03F 7/40 20060101
G03F007/40; G03F 7/00 20060101 G03F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 14, 2017 |
JP |
2017-025229 |
Claims
1. A substrate treating method for performing a heat treatment of a
substrate having a treated film formed thereon in a heat treating
space of a heat treating chamber, the substrate treating method
comprising: an exhaust step of exhausting gas within the heat
treating space formed by a cover enclosing surroundings of a heat
treating plate; an inert gas supply step of supplying inert gas
from an upper portion of the heat treating space into the heat
treating space and supplying inert gas into a gap between an outer
peripheral surface of the heat treating plate and an inner wall of
the cover; and a heat treating step of performing the heat
treatment of the substrate in the heat treating space, the heat
treating step being performed after the exhaust step and the inert
gas supply step.
2. The substrate treating method according to claim 1, wherein the
heat treating step is performed while exhaust from through holes
into which support pins moving forward/backward from the heat
treating plate are inserted is only performed and exhaust from an
exhaust port of the cover stops.
3. The substrate treating method according to claim 1, wherein the
treated film is made from a directed self-assembly material.
4. The substrate treating method according to claim 2, wherein the
treated film is made from a directed self-assembly material.
5. A substrate treating apparatus for performing a heat treatment
of a substrate having a treated film formed thereon in a heat
treating space, the substrate treating apparatus comprising: a heat
treating plate where the substrate to be treated is placed; a cover
that is erected outwardly from an outer peripheral surface of the
heat treating plate by a gap, and encloses surroundings of the heat
treating plate to form a heat treating space inside thereof; an
upper inert gas supplying device that supplies inert gas from an
upper portion of the heat treating space into the heat treating
space; openings formed in the cover in communication with the gap;
a lower inert gas supplying device that supplies inert gas into the
openings; an exhaust device that exhausts gas within the heat
treating space; and a controller that causes the exhaust device to
exhaust the gas within the heat treating space, and causes the
upper inert gas supplying device and the lower inert gas supplying
device to supply the inert gas, and thereafter performs the heat
treatment of the substrate placed on the heat treating plate.
6. The substrate treating method according to claim 5, wherein the
cover includes the openings formed therein at two positions that
are opposite to each other across the center of the heat treating
plate in plan view.
7. The substrate treating method according to claim 5, wherein the
heat treating plate includes through holes into which support pins
for delivering the substrate are inserted in communication with the
heat treating space, the cover includes an exhaust port in
communication with the heat treating space, the exhaust device
performs exhaust from the through holes and exhaust from the
exhaust port, and the controller performs the heat treatment of the
substrate while causing the exhaust device to stop the exhaust from
the exhaust port and to perform only the exhaust from the through
holes.
8. The substrate treating method according to claim 6, wherein the
heat treating plate includes through holes into which support pins
for delivering the substrate are inserted in communication with the
heat treating space, the cover includes an exhaust port in
communication with the heat treating space, the exhaust device
performs exhaust from the through holes and exhaust from the
exhaust port, and the controller performs the heat treatment of the
substrate while causing the exhaust device to stop the exhaust from
the exhaust port and to perform only the exhaust from the through
holes.
9. The substrate treating method according to claim 5, wherein the
treated film is made from a directed self-assembly material.
10. The substrate treating method according to claim 6, wherein the
treated film is made from a directed self-assembly material.
11. The substrate treating method according to claim 7, wherein the
treated film is made from a directed self-assembly material.
12. The substrate treating method according to claim 8, wherein the
treated film is made from a directed self-assembly material.
13. The substrate treating method according to claim 5, wherein the
lower inert gas supplying device allows regulation of a flow rate
of the nitrogen gas.
14. The substrate treating method according to claim 6, wherein the
lower inert gas supplying device allows regulation of a flow rate
of the nitrogen gas.
15. The substrate treating method according to claim 7, wherein the
lower inert gas supplying device allows regulation of a flow rate
of the nitrogen gas.
16. The substrate treating method according to claim 8, wherein the
lower inert gas supplying device allows regulation of a flow rate
of the nitrogen gas.
17. The substrate treating method according to claim 9, wherein the
lower inert gas supplying device allows regulation of a flow rate
of the nitrogen gas.
18. The substrate treating method according to claim 10, wherein
the lower inert gas supplying device allows regulation of a flow
rate of the nitrogen gas.
19. The substrate treating method according to claim 11, wherein
the lower inert gas supplying device allows regulation of a flow
rate of the nitrogen gas.
20. The substrate treating method according to claim 12, wherein
the lower inert gas supplying device allows regulation of a flow
rate of the nitrogen gas.
Description
BACKGROUND OF THE INVENTION
(1) Field of the Invention
[0001] The present invention relates to a substrate treating method
and an apparatus used therefor for performing a heat treatment of a
semiconductor wafer, a substrate for liquid crystal display, a
substrate for flat panel display (FPD) like a substrate for organic
electroluminescence (EL), a substrate for optical display, a
magnetic disk substrate, an optical magnetic disk substrate, a
substrate for photomask, and a solar cell substrate (hereinafter,
simply referred to as a substrate).
(2) Description of the Related Art
[0002] In recent process technologies, attention has been focused
on a DSA process, for example, as a technology instead of immersion
lithography or extreme ultraviolet (EUV) lithography. The DSA
process is performed with a directed self-assembly (DSA) technology
using micro phase separation of a block co-polymer for achieving
much finer design rules on substrates.
[0003] In the currently-used substrate treating method in the DSA
process, a block co-polymer (BCP) is applied to a substrate for
deposition of a treated film, and thereafter, a heat treatment of
heating the treated film on the substrate is performed in a heat
treating space of a heat treating chamber, whereby (phase)
separation of two types of polymers in the treated film is
performed. Then, etching is performed to one of the (phase)
separated polymers, whereby fine patterns are formed. See, for
example, Japanese Unexamined Patent Publication No.
2014-22570A.
[0004] However, the example of the currently-used apparatus with
such a configuration has the following problems.
[0005] Specifically, in the currently-used method, such a problem
may arise as the polymer in the treated film is not able to be
separated appropriately depending on a treatment atmosphere in the
heat treating space. Moreover, the deposited film may pose some
difficulty in its property and performance depending on a treatment
atmosphere in the heat treating space also during a process of
performing heat treatment of the substrate within the heat treating
chamber other than the DSA process, the process including process
of depositing a film by a heat treatment after a spin on glass
(SOG) solution is applied to the substrate.
SUMMARY OF THE INVENTION
[0006] The present invention has been made regarding the state of
the art noted above, and its one object is to provide a substrate
treating method and an apparatus used therefor that allow
appropriate film deposition by producing a suitable treatment
atmosphere in a heat treating space in a heat treating process.
[0007] To fulfill the above object, Inventors of the present
invention have made intensive research and attained the following
findings. Attention was focused on an influence of oxygen in a heat
treating space in view of a relationship between various parameters
of the heat treating space and a separated condition of a polymer
after a heat treatment under different treatment atmospheres in the
heat treating space of the heat treating chamber. Such attention
was made based on the finding that inappropriate phase separation
of the polymers was performed during the heat treatment where an
oxygen concentration in the heat treating space was lowered
incompletely. Now, it is estimated that, if the oxygen
concentration is lowered incompletely, the polymer is adversely
affected during phase separation thereof, and accordingly normal
phase separation is inhibited. Also in heat treatment processes
other than the DSA process, oxidation caused by oxygen adversely
affects a property of film deposition. The present invention based
on such finding as above is constituted as under.
[0008] One aspect of the present invention provides a substrate
treating method for performing a heat treatment of a substrate
having a treated film formed thereon in a heat treating space of a
heat treating chamber. The method includes an exhaust step of
exhausting gas within the heat treating space formed by a cover
enclosing surroundings of a heat treating plate; an inert gas
supply step of supplying inert gas into the heat treating space
from an upper portion of the heat treating space and supplying
inert gas into a gap between an outer peripheral surface of the
heat treating plate and an inner wall of the cover; and a heat
treating step of performing the heat treatment of the substrate in
the heat treating space, the heat treating step being performed
after the exhaust step and the inert gas supply step.
[0009] With the aspect of the present invention, the exhaust step
is performed to exhaust the gas within the heat treating space. The
inert gas supply step is performed to supply the inert gas from the
upper portion of the heat treating space, and to supply the inert
gas into the gap between the outer peripheral surface of the heat
treating plate and the inner wall of the cover. The gap between the
outer peripheral surface of the heat treating plate and the inner
wall of the cover is narrow, and oxygen stagnated in the gap is not
able to be replaced sufficiently only with the supply of the inert
gas from the upper portion of the heat treating space. Accordingly,
the inert gas is also supplied to the gap. Consequently, the oxygen
stagnated in the gap is able to be replaced by the inert gas,
achieving an extremely lowered oxygen concentration in the heat
treating space. As a result, the treatment atmosphere within the
heat treating space during the heat treating step is able to be
made suitable for the heat treating process, leading to appropriate
film deposition.
[0010] Moreover, it is preferred in the aspect of the present
invention that, the heat treating step is performed while exhaust
from through holes into which support pins moving forward/backward
from the heat treating plate are inserted is only performed and
exhaust from an exhaust port of the cover stops.
[0011] The exhaust from the through holes located adjacent to a
lower surface of the substrate is only performed, achieving stable
airflow in the heat treatment atmosphere around a top face of the
substrate. Consequently, a heat treatment of a treated film is
performable in a stable manner.
[0012] Moreover, it is preferred in the aspect of the present
invention that the treated film is made from a directed
self-assembly material.
[0013] This makes the treatment atmosphere in the heat treating
space suitable for the DSA process, achieving appropriate
separation of the polymer.
[0014] Another aspect of the present invention provides a substrate
treating apparatus for performing a heat treatment of a substrate
having a treated film formed thereon in a heat treating space. The
apparatus includes a heat treating plate where the substrate to be
treated is placed; a cover that is erected outwardly from an outer
peripheral surface of the heat treating plate by a gap, and
encloses surroundings of the heat treating plate to form a heat
treating space inside thereof; an upper inert gas supplying device
that supplies inert gas from an upper portion of the heat treating
space into the heat treating space; openings formed in the cover in
communication with the gap; a lower inert gas supplying device that
supplies inert gas into the openings; an exhaust device that
exhausts gas within the heat treating space; and a controller that
causes the exhaust device to exhaust the gas within the heat
treating space, and causes the upper inert gas supplying device and
the lower inert gas supplying device to supply the inert gas, and
thereafter performs the heat treatment of the substrate placed on
the heat treating plate.
[0015] With the aspect of the present invention, the controller
causes the exhaust device to exhaust the gas within the heat
treating space, and causes the upper inert gas supplying device and
the lower inert gas supplying device to supply the inert gas. The
inert gas is supplied from the upper portion of the heat treating
space and the openings in communication with the gap between the
outer peripheral surface of the heat treating plate and the cover.
Accordingly, oxygen stagnated in the gap is able to be replaced by
the inert gas, achieving an extremely lowered oxygen concentration
in the heat treating space. As a result, the treatment atmosphere
within the heat treating space during the heat treating step is
able to be made suitable for the heat treating process, leading to
appropriate film deposition.
[0016] Moreover, it is preferred in the embodiment of the present
invention that the cover includes the openings formed therein at
two positions that are opposite to each other across the center of
the heat treating plate in plan view.
[0017] Since the inert gas is supplied from the openings at the two
positions opposite to each other, an enough amount of the inert gas
is able to be supplied to the entire periphery of the gap in
contrast to a situation where the inert gas is supplied from one
position. Consequently, oxygen stagnated into the gap is able to be
replaced sufficiently by the inert gas.
[0018] Moreover, it is preferred in the aspect of the present
invention that the heat treating plate includes through holes into
which support pins for delivering the substrate are inserted in
communication with the heat treating space, the cover includes an
exhaust port in communication with the heat treating space, the
exhaust device performs exhaust from the through holes and exhaust
from the exhaust port, and the controller performs the heat
treatment of the substrate while causing the exhaust device to stop
the exhaust from the exhaust port and to perform only the exhaust
from the through holes.
[0019] The controller performs the heat treatment of the substrate
while causing the exhaust device to stop the exhaust from the
exhaust port and to perform the exhaust from only the through
holes. The exhaust is performed only from the through holes
adjacent to the lower surface of the substrate, leading to stable
airflow in the heat treatment atmosphere around the top face of the
substrate. Consequently, the heat treatment of the treated film is
able to be performed in a stable manner.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] For the purpose of illustrating the invention, there are
shown in the drawings several forms which are presently preferred,
it being understood, however, that the invention is not limited to
the precise arrangement and instrumentalities shown.
[0021] FIG. 1 schematically illustrates an overall configuration of
a substrate treating apparatus according to one embodiment of the
present invention.
[0022] FIG. 2 is a plan view around a heat treating plate.
[0023] FIG. 3 is a longitudinal sectional view around the heat
treating plate.
[0024] FIG. 4 is a time chart illustrating one example of treating
a substrate according to the embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The following describes one embodiment of the present
invention with reference to drawings.
[0026] FIG. 1 schematically illustrates an overall configuration of
a substrate treating apparatus according to one embodiment of the
present invention. FIG. 2 is a plan view around a heat treating
plate, and FIG. 3 is a longitudinal sectional view around the heat
treating plate.
[0027] The substrate treating apparatus according to the present
embodiment for executing a substrate treating method is used for
performing a heat treatment of a substrate W. Examples of the
substrate W in the present embodiment include one having a treated
film made from a directed self-assembly material deposited on a
front face thereof.
[0028] The substrate treating apparatus according to the present
embodiment includes a heat treatment plate unit 1, a heat treating
chamber 3, an upper gas supply unit 5, a shutter 7, a chamber
exhaust unit 9, a support pin lifting member 11, a lower gas supply
unit 13, a support pin seal exhaust unit 15, a controller 17, and a
setting unit 19.
[0029] The heat treatment plate unit 1 places the substrate W on
its top face for performing a heat treatment of the substrate W.
The heat treatment plate unit 1 includes a base plate 21, a heat
treating plate 23, and a heater 25. The base plate 21 is attached
to a lower part of the heat treating plate 23, and is also attached
to a lower part of the heat treating chamber 3 together with the
heat treating plate 23. The heat treating plate 23 is composed of a
material whose base material is a metal, such as copper (Cu) and
aluminum (Al), with a high thermal conductivity. The heater 25 is
embedded in the heat treating plate 23, and controls a temperature
of the heat treating plate 23. For instance, the heater 25 controls
a temperature of the heat treating plate 23 within a range of 300
to 400.degree. C. The heat treating plate 23 has proximity balls,
not shown, embedded in its top face for locating a rear face of the
substrate W away from a top face of the heat treating plate 23 by a
given interval (e.g., 0.1 mm).
[0030] As illustrated in FIG. 2, the heat treating plate 23 has
through holes 27 formed at positions corresponding to vertexes of a
regular triangle in plan view. The through holes 27 each pass from
the top face to the rear face of the heat treating plate 23, and
also pass through the base plate 21. Holder pins mentioned later
are inserted into the through holes 27, respectively. Moreover, a
topside plate supply port 29 passing the heat treating plate 23 and
the base plate 21 in a vertical direction is formed around the
center of the heat treating plate 23.
[0031] The heat treating chamber 3 includes a cover 31. The cover
31 includes an opening at a lower portion thereof, and the heat
treatment plate unit 1 is attached to the opening. The cover 31
shows a shape that covers a lateral side and an upper side of the
heat treatment plate unit 1. A space is formed between the ceiling
of the cover 31 and the top face of the heat treating plate 23. The
space corresponds to a heat treating space HS. The cover 31 has a
load outlet 33 formed on a first side face thereof. The load outlet
33 is used for loading a substrate W to be treated into the heat
treating space HS and unloading the treated substrate W from the
heat treating space HS. A cooling pipe 35 is attached around the
load outlet 33. The cooling pipe 35 cools the cover 31 with cooling
water supplied thereto, and protects an O-ring around the load
outlet 33.
[0032] The cover 31 has an exhaust port 37 formed on a second side
face thereof, which is opposite to the load outlet 33. The exhaust
port 37 is used for exhausting gas within the cover 31. The exhaust
port 37 has a flow path sectional area corresponding to a vertical
sectional area of the heat treating space HS. An exhaust port cover
39 is removably attached to the outside of the exhaust port 37 via
the O-ring. The ceiling of the cover 31 includes a plurality of
through holes 41. An annular gap 43 in plan view is present between
the heat treatment plate unit 1 and an outer peripheral surface of
the heat treating plate 23 of the cover 31 around the heat
treatment plate unit 1. A side face of the cover 31 facing to the
gap 43 has openings 45 each in communication with the gap 43. The
openings 45 are, for example, formed at two positions opposite to
each other across the center of the heat treating plate 23 in plan
view as in FIG. 2. The cooling pipe 35 is disposed at an outer face
of the cover 31 below the openings 45 as in FIGS. 1 and 3. The
cooling pipe 35 protects the O-ring between the cover 31 and the
base plate 21. The lower gas supply unit 13 supplies nitrogen gas
into the openings 45 and the topside plate supply port 29. The
lower gas supply unit 13 includes a plurality of flow rate
regulating valves or on-off valves for allowing regulation of a
flow rate of the nitrogen gas.
[0033] The exhaust port 37 exhausts gas through the exhaust port
having the flow path sectional area corresponding to the vertical
sectional area of the heat treating space HS, leading to efficient
exhaust.
[0034] Here, the lower gas supply unit 13 corresponds to the "lower
inert gas supplying device" in the present invention.
[0035] A pressure sensor 47 is disposed above the cover 31 adjacent
to the load outlet 33. An oxygen concentration sensor 49 is
disposed above the cover 31 adjacent to the exhaust port 37. The
pressure sensor 47 determines pressure within the heat treating
space HS. The oxygen concentration sensor 49 determines an oxygen
concentration within the heat treating space HS. As is described
hereunder, it should be noted that the oxygen concentration sensor
49 is only used when an examination to determine lapsed time during
which the oxygen concentration is lowered to a target value or
less, and accordingly, the oxygen concentration sensor 49 is not
necessarily provided during normal treatment.
[0036] A gas supply buffer 51 is disposed above the cover 31. Here,
nitrogen (N.sub.2) gas supplied from the center of the top face of
the cover 31 is supplied from an underside opening of the cover 31,
having a larger area than the center of the top face, through a
plurality of through holes 41 into the heat treating space HS. An
O-ring is disposed between the top face of the cover 31 and an
under face of the gas supply buffer 51. Another, cooling pipe 35 is
disposed inside of the gas supply buffer 51. The cooling pipe 35
protects the O-ring. The upper gas supply unit 5 supplies nitrogen
gas as inert gas into the gas supply buffer 51 mentioned above. The
upper gas supply unit 5 includes two flow rate regulating valves,
for example, that allow switch of a flow rate of the nitrogen gas
in two steps.
[0037] Here, the gas supply buffer 51 corresponds to the "upper
inert gas supplying device" in the present invention.
[0038] The shutter 7 is disposed on a front face of the load outlet
33. The shutter 7 includes the load outlet 33, a shutter body 57,
and an actuator 59. The shutter body 57 is lifted by the actuator
59 whose actuating pieces move upwardly/downwardly in a vertical
direction. The shutter body 57 closes the load outlet 33 via the
O-ring when moving upwardly. When the actuator 59 is brought into
an actuated state, the shutter body 57 moves to a position denoted
by solid lines in FIG. 1 to close the load outlet 33. When the
actuator 59 is brought into a non-actuated state, the shutter body
57 moves downwardly to a position denoted by chain double-dashed
lines in FIG. 1 to open the load outlet 33.
[0039] The chamber exhaust unit 9 exhausts gas within the heat
treating space HS via the exhaust port cover 39 mentioned above.
The chamber exhaust unit 9 includes a plurality of on-off valves,
flow rate regulating valves, aspirators, and the like, for
exhausting the gas within the heat treating space HS by supplying
air from an air supplying source. It should be noted that the
chamber exhaust unit 9 may be formed by an exhaust pump and the
like instead of the aspirators and the air supplying source.
[0040] The support pin lifting member 11 includes three support
pins 61 (two of which are only denoted in FIG. 1 for an
illustrational reason), a manifold 63, mechanical seals 65, a
lifting member 67, and an actuator 69. The support pins 61 are
inserted into the through holes 27, respectively. The support pins
61 pass through the manifold 63 and are coupled at lower ends
thereof to the lifting member 67 via the mechanical seals 65. An
O-ring is attached between the top face of the manifold 63 and the
base plate 21 so as to surround each of the through holes 27. Upper
ends of the mechanical seals 65 are attached to an under face of
the manifold 63. The mechanical seals 65 are metal seals that allow
upward/downward movement of the support pins 61 while supporting
outer peripheral surfaces of the support pins 61 in a sealing
manner. The manifold 63 shows a triangle shape in plan view, and
has one space formed therein. The manifold 63 has an exhaust port
71 formed at one region thereof in communication with the
space.
[0041] The lifting member 67 shows an annular shape in plan view,
and is moved upwardly/downwardly by the actuator 69. The actuator
69 is disposed in an attitude where the actuating pieces are moved
forward/backward in the vertical direction. When the actuator 69 is
brought into an actuated state, the support pins 61 project to move
to the delivery position denoted by chain double-dashed lines in
FIG. 1. When the actuator 69 is brought into a non-actuated state,
the support pins 61 moves to the retracted position denoted by
solid lines in FIG. 1. When the support pins 61 move to the
retraced position, the substrate W is placed on the top face of the
heat treating plate 23.
[0042] The support pin seal exhaust unit 15 exhausts gas from an
exhaust port 71 of the manifold 63. The support pin seal exhaust
unit 15 includes a plurality of on-off valves, flow rate regulating
valves, aspirators, and the like for exhausting gas within the heat
treating space HS through the manifold 63 and the through holes 27
by supplying air from an air supplying source. In addition, dust
generated on the mechanical seals 65 is discharged simultaneously.
It should be noted that the support pin seal exhaust unit 15 may be
formed by a vacuum pump instead of the aspirators and the air
supplying source.
[0043] The support pin seal exhaust unit 15 exhausts gas from the
through holes 27 that are formed near a position where the
substrate W is placed during the heat treatment. This achieves
effective reduction in oxygen concentration around the substrate W
that may influence film deposition largely during the heat
treatment. Moreover, since the dust generated due to slide of the
support pins 61 on the mechanical seals 65 is discharged without
entering into the heat treating space HS, the substrate W is able
to be treated cleanly.
[0044] Here, the through holes 27 and the exhaust port 37
correspond to the "exhaust device" in the present invention.
[0045] The upper gas supply unit 5, the chamber exhaust unit 9, the
lower gas supply unit 13, the support pin seal exhaust unit 15, and
the actuators 59, 69 are controlled en bloc by a controller 17. The
controller 17 contains a CPU, a memory, and a timer, each of which
is not shown. The controller 17 causes the memory, not shown, to
store in advance a plurality of recipes that specific procedures of
the heat treatment. The setting unit 19 is operated by an operator
to select one of the recipes and to provide an instruction for
starting treatment or for operation when an alarm is given.
[0046] In the present embodiment, the memory not shown stores in
advance a chamber exhaust time, a heat treatment shifting time, a
heat treating time, a cooling time, and the like, and such time is
referred to by the controller 17 as appropriately. The heat
treatment shifting time is lapsed time from an exhaust starting
time when the oxygen concentration within the heat treating space
HS is lowered to the target value or less in the heat treatment,
which is to be mentioned later. This time is measured and
determined in advance through examinations while the oxygen
concentration sensor 49 is provided.
[0047] The following describes one example of the heat treatment by
the substrate treating apparatus with reference to FIG. 4. FIG. 4
is a time chart illustrating one example of treating a substrate
according to the embodiment. Here, pressure within the heat
treating space HS is denoted by solid lines, and an oxygen
concentration in the heat treating space HS is denoted by dotted
lines in the time chart of FIG. 4. At time 0, the controller 17
causes the support pin seal exhaust unit 15 to start exhaust from
the exhaust port 71, and causes the chamber exhaust unit 9 to start
exhaust from the exhaust port 37. Accordingly, gas within the heat
treating space HS starts to be exhausted, and pressure is sharply
decreased to -p3 kPa at time t1 as the chamber exhaust time. It
should be noted that the condition to make the pressure decreased
to -p3 kPa at the time t1 as the chamber exhaust time is determined
in advance through various examinations of adjusting an exhaust
amount from the chamber exhaust unit 9 and the support pin seal
exhaust unit 15. Simultaneously, the controller 17 also starts
clocking. Such sharp exhaust produces the effect of preventing air
from entering from the outside into the heat treating space HS by
causing the shutter body 57 to adhere to the O-ring of the load
outlet 33 tightly.
[0048] After clocking the time t1 as the chamber exhaust time, the
controller 17 causes the upper gas supply unit 5 and the lower gas
supply unit 13 to start supply of nitrogen gas. Accordingly,
pressure within the heat treating space HS moves back sharply to
the atmospheric pressure while negative pressure of around -p 1 kPa
is maintained. This is achieved by making the supply amount of
nitrogen gas from the upper gas supply unit 5 and the lower gas
supply unit 13 less than the exhaust amount from the chamber
exhaust unit 9 and the support pin seal exhaust unit 15. During a
period of the time t1 to time t7, the oxygen concentration is
lowered through the exhaust and the supply of the nitrogen gas.
[0049] During the period of the time t1 to the time t7, the
negative pressure is maintained with the exhaust amount larger than
the supply amount of the nitrogen gas. The oxygen stagnated at
corners within the heat treating chamber 3 and the like is
discharged by flow of the nitrogen gas more easily than by flow of
the exhaust. Accordingly, this achieves more reduction in oxygen
concentration.
[0050] The controller 17 causes the chamber exhaust unit 9 to stop
at the time t7 corresponding to time after a given period of time
from the time 0, and the processing is shifted to exhaust via the
through holes 27 (support pin seal exhaust) and reduction in oxygen
concentration by purge of supplying nitrogen gas from the upper gas
supply unit 5 and the lower gas supply unit 13. This reduces a flow
rate of exhaust, leading to variation in pressure of the heat
treating space HS toward the atmospheric pressure to maintain the
pressurized space.
[0051] At this time, oxygen may possibly be stagnated in the gap 43
around the heat treating plate 23. Then, supplying nitrogen gas
from the openings 45 leads to exhaust of the stagnated oxygen along
with the flow of the nitrogen gas as in FIG. 3. Consequently, an
extremely lowered oxygen concentration is obtainable in the heat
treating space HS.
[0052] When the clocking time has reached the heat treatment
shifting time set in advance, the controller 17 causes the support
pins 61 to move downwardly to shift the processing to the heat
treatment. During the period of time t7 to time t9, chamber exhaust
is stopped and exhaust via the through holes 27 (support pin seal
exhaust) and supply of the nitrogen gas are performed, leading to
flow variation within the heat treating space HS until the time t7.
Accordingly, discharge of the oxygen stagnated in the heat treating
space HS is obtainable along with the flow variation, achieving a
more lowered oxygen concentration.
[0053] Here, the period of the time t1 to the time t9 mentioned
above corresponds to the "exhaust step" and the "inert gas supply
step" in the present invention.
[0054] When the time has reached the heat treatment shifting time,
the controller 17 causes the actuator 69 to be brought into a
non-actuated state, and causes the support pins 61 to move
downwardly to the retracted position. Accordingly, the substrate W
is placed on the top face of the heat treating plate 23, and the
heat treatment of the substrate W is started. The controller 17
starts clocking and maintains this condition until time t10 at
which the time reaches the heat treating time. Here, in the time
t9, the oxygen concentration in the heat treating space HS is
lowered to 100 ppm or less as the target value.
[0055] As noted above, the process is able to be shifted to the
heat treatment by merely measuring the heat treating time without
using any oxygen concentration meter 49. This achieves the
simplified configuration of the substrate treating apparatus,
leading to reduction in cost needed for the processing.
[0056] When the clocking time has reached the heat treating time,
the controller 17 causes the actuator 69 to actuate at the time t10
to move the support pins 61 upwardly. Accordingly, the substrate W
is moved away from the heat treating plate 23 to the delivery
position. The controller 17 causes the chamber exhaust unit 9 to
actuate to start exhaust from the exhaust port 37, and to start
clocking. This causes cooling of the substrate W.
[0057] The period of time t9 to t10 corresponds to the "heat
treating step" in the present invention.
[0058] When the clocking time reaches the cooling time, the
controller 17 causes the chamber exhaust unit 9, the upper gas
supply unit 5, and the lower gas supply unit 13 at the time t11 to
stop. Then, the actuator 59 is brought into a non-actuation
condition, and the shutter body 57 is moved downwardly for
unloading the substrate W.
[0059] With the aspect of the present embodiment, the gas within
the heat treating space HS is exhausted. The nitrogen gas is
supplied from the upper portion of the heat treating space HS and
from the openings 45 to the gap 43 between the outer peripheral
surface of the heat treating plate 23 and the inner wall of the
cover 31. The gap 43 between the outer peripheral surface of the
heat treating plate 23 and the inner wall of the cover 31 is
narrow, and oxygen stagnated in the gap 43 is not able to be
replaced sufficiently only with the supply of the inert gas from
the upper portion of the heat treating space. Accordingly, the
nitrogen gas is also supplied from the openings 45 to the gap 43.
Consequently, oxygen stagnated in the gap 43 is also able to be
replaced by the nitrogen gas, achieving an extremely lowered oxygen
concentration in the heat treating space HS. As a result, the
treatment atmosphere within the heat treating space HS is able to
be made suitable for the heat treating process, leading to
appropriate film deposition.
[0060] (1) In the embodiment mentioned above, the substrate W has a
treated film coated thereon that is made from a directed
self-assembly material. Such a substrate W is not limitative in the
present invention. For instance, the present invention is
applicable to the treatment that the oxygen concentration in the
heat treating space HS adversely affects, such as treatment for a
substrate to which a spin on glass (SOG) solution is applied.
[0061] (2) In the embodiment mentioned above, the openings 45 are
formed at the two positions opposite to each other across the
center of the heat treating plate 23 in plan view. However, such is
not limitative in the present invention. For instance, the openings
45 may be formed at three or more positions. Alternatively, the
openings 45 are not necessarily formed at the position opposite to
each other across the center of the heat treating plate 23.
[0062] (3) In the embodiment mentioned above, the exhaust from the
exhaust port 37 stops in the heat treating step. However, the
exhaust from the exhaust port 37 may be successively performed as
long as no influence is exerted on the film deposition. This
achieves simplified control.
[0063] (4) In the embodiment mentioned above, nitrogen gas has been
described as one example of the inert gas. However, another type of
inert gas such as argon or helium may be used.
[0064] The present invention may be embodied in other specific
forms without departing from the spirit or essential attributes
thereof and, accordingly, reference should be made to the appended
claims, rather than to the foregoing specification, as indicating
the scope of the invention.
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