U.S. patent application number 11/337314 was filed with the patent office on 2006-06-15 for substrate processing apparatus and substrate processing method drying substrate by spraying gas.
This patent application is currently assigned to Dainippon Screen Mfg. Co., Ltd.. Invention is credited to Akira Izumi.
Application Number | 20060123658 11/337314 |
Document ID | / |
Family ID | 31972832 |
Filed Date | 2006-06-15 |
United States Patent
Application |
20060123658 |
Kind Code |
A1 |
Izumi; Akira |
June 15, 2006 |
Substrate processing apparatus and substrate processing method
drying substrate by spraying gas
Abstract
A first gas nozzle and a second gas nozzle are fixedly provided
in the vicinity of the forward end of a nozzle arm. The nozzle arm
is rotated along a locus R while a substrate rinsed with deionized
water is rotated, for discharging nitrogen gas from the first and
second gas nozzles. Visible moisture is loosely expelled from the
upper surface of the substrate by spraying the nitrogen gas from
the first gas nozzle, and moisture slightly remaining on a fine
pattern or the like can also be completely removed by spraying the
nitrogen gas from the second gas nozzle to the same region of the
substrate as that sprayed with the nitrogen gas by the first gas
nozzle. Consequently, the surface of the substrate can be stably
and reliably dried. Thus, a substrate processing apparatus capable
of stably and reliably drying the surface of the substrate is
provided.
Inventors: |
Izumi; Akira; (Kyoto,
JP) |
Correspondence
Address: |
OSTROLENK FABER GERB & SOFFEN
1180 AVENUE OF THE AMERICAS
NEW YORK
NY
100368403
US
|
Assignee: |
Dainippon Screen Mfg. Co.,
Ltd.
|
Family ID: |
31972832 |
Appl. No.: |
11/337314 |
Filed: |
January 23, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10634432 |
Aug 5, 2003 |
7017281 |
|
|
11337314 |
Jan 23, 2006 |
|
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Current U.S.
Class: |
34/565 ; 34/492;
34/523 |
Current CPC
Class: |
Y10S 134/902 20130101;
H01L 21/67034 20130101 |
Class at
Publication: |
034/565 ;
034/492; 034/523 |
International
Class: |
F26B 3/00 20060101
F26B003/00; F26B 21/00 20060101 F26B021/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 30, 2002 |
JP |
JP2002-254214 |
Claims
1-12. (canceled)
13. A substrate processing method spraying gas to a substrate
completely cleaned with deionized water for drying said substrate,
comprising steps of: (a) spraying said gas to the surface of said
substrate wet with said deionized water; and (b) further spraying
said gas to the same region as the region on said substrate already
sprayed with said gas in said step a).
14. The substrate processing method according to claim 13, wherein
the flow rate of said gas sprayed to said substrate in said step b)
is larger than the flow rate of said gas sprayed to said substrate
in said step a).
15. The substrate processing method according to claim 14, wherein
said gas is inert gas.
16. The substrate processing method according to claim 13, wherein
said steps a) and b) are performed while rotating said
substrate.
17. The substrate processing method according to claim 16, further
comprising the step of: c) after said steps a) and b), rotating
said substrate a number of revolutions higher than the numbers of
revolutions of said substrate in said steps a) and b).
18. The substrate method according to claim 16, wherein arrival
points of said gas sprayed in said steps a) and b) are moved to
draw loci directed from a rotation center of said substrate toward
an edge.
19. The substrate processing method according to claim 18, wherein
the spray of said gas to said rotation center of said substrate is
started in step b) while said deionized water is fed from said
rotation center of said substrate toward said edge in said step
a).
20. The substrate processing method according to claim 18, wherein
the spray of said gas to said rotation center of said substrate is
started in step b) immediately after said deionized water is fed
from said rotation center of said substrate toward said edge and
the arrival point of said gas sprayed to said substrate reaches
said edge in said step a).
21. The substrate processing method according to claim 13, further
comprising the steps of: d) forming a paddle of said deionized
water in the upper surface of said substrate prior to said step
a).
22. A substrate processing apparatus spraying gas to a substrate
completely cleaned with deionized water for drying said substrate,
comprising: a first gas discharge element spraying said gas to the
surface of said substrate wet with said deionized water; and a
second gas discharge element further spraying said gas to the same
region as the region already sprayed with said gas by said first
gas discharge element, wherein the flow rate of said gas sprayed
from said second gas discharge element to said substrate is larger
than the flow rate of said gas sprayed from said first gas
discharge element to said substrate, further comprising a rotation
element rotating said substrate substantially in a horizontal
plane, wherein, said first gas discharge element comprises: a first
nozzle discharging said gas, and a first nozzle moving element
moving said first nozzle substantially in a horizontal plane, said
second gas discharge element comprises: a second nozzle discharging
said gas, and a second nozzle moving element moving said nozzle
substantially in a horizontal plane, and said first nozzle moving
element and said second nozzle moving element move the respective
ones of said first nozzle and said second nozzle so that arrival
points of said gas discharged from the respective ones of said
first nozzle and said second nozzle draw loci directed from the
rotation center of rotated said substrate toward the edge.
23. The substrate processing apparatus according to claim 22,
wherein said gas is inert gas.
24. A substrate processing apparatus spraying gas to a substrate
completely cleaned with deionized water for drying said substrate,
comprising: a nozzle spraying said gas to the surface of said
substrate wet with said deionized water; a nozzle arm fixedly
provided with said nozzle; and a moving element moving said nozzle
arm in a plane substantially parallel to said substrate, wherein
said moving element moves said nozzle arm to re-spray said gas by
said nozzle to the same region as the region on said substrate
sprayed with gas by said nozzle.
25. The substrate processing apparatus according to claim 24,
wherein the flow rate of said gas re-sprayed from said nozzle to
said substrate is larger than the flow rate of said gas precedently
sprayed from said nozzle to said substrate.
26. The substrate processing apparatus according to claim 25,
further comprising a rotation element rotating said substrate
substantially in a horizontal plane, wherein said moving element
moves said nozzle arm substantially in a horizontal plane so that
arrival points of said gas precedently and subsequently discharged
from said nozzle draw loci directed from the rotation center of
rotated said substrate toward the edge.
27. The substrate processing apparatus according to claim 26,
wherein said gas is inert gas.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a substrate processing
apparatus, particularly a single-substrate type substrate
processing apparatus, and a substrate processing method spraying
gas to a semiconductor substrate, a glass substrate for a liquid
crystal display, a glass substrate for a photomask, a substrate for
an optical disk or the like (hereinafter simply referred to as
"substrate") for drying the substrate.
[0003] 2. Description of the Background Art
[0004] A single-substrate type substrate processing apparatus
supplying a chemical solution such as hydrofluoric acid to a
substrate while rotating the same for etching or cleaning the
substrate generally performs rinse processing with deionized water
after the chemical solution processing, followed by drying
processing for removing the deionized water adhering to the
substrate. In general, such a substrate processing apparatus dries
the substrate by a technique of rotating the substrate thereby
spinning off the same as proposed in Japanese Patent Application
Laying-Open Gazette No. 11-233481 (1999), for example.
[0005] In order to dry a large substrate such as a substrate for a
liquid crystal display, the so-called air knife may be employed for
spraying stratified gas from a slitlike discharge port to the
surface of the substrate, as proposed in Japanese Patent
Application Laying-Open Gazette No. 11-111666 (1999), for
example.
[0006] In a drying step subsequent to the rinse processing with
deionized water, however, imperfect drying may result in the form
of water marks, which are readily caused particularly when the
substrate processing apparatus etches silicon (Si) or polysilicon
forming the surface of the substrate with hydrofluoric acid due to
partial exposure of a hydrophobic surface. Oxygen contained in the
atmosphere may conceivably be dissolved into moisture adhering to
the surface of the substrate and react with Si to result in
residues, which in turn form such water marks due to drying.
[0007] In order to prevent formation of such water marks, IPA
(isopropyl alcohol) may be sprayed to the surface of the substrate
in the drying processing for replacing the moisture with IPA.
According to this method, however, combustible IPA is handled in
the form of a liquid or gas, and hence the apparatus must be
brought into an explosion-proof structure in consideration of
safety. In view of the process, the conditional range for replacing
the residual moisture with IPA is so narrow that reproducibility
for prevention of water marks is hard to attain. When the organic
IPA is supplied to the surface of the substrate in the final drying
step, increasingly refined device characteristics may
disadvantageously be deteriorated.
SUMMARY OF THE INVENTION
[0008] The present invention is directed to a substrate processing
apparatus spraying gas to a substrate completely cleaned with
deionized water for drying the substrate.
[0009] According to the present invention, the substrate processing
apparatus comprises a first gas discharge element spraying the gas
to the surface of the substrate wet with the deionized water and a
second gas discharge element further spraying the gas to the same
region as the region already sprayed with the gas by the first gas
discharge element.
[0010] The substrate processing apparatus can also completely
remove a trace of moisture remaining on the surface of the
substrate for stably and reliably drying the surface of the
substrate.
[0011] According to an aspect of the present invention, the
substrate processing apparatus comprises a first nozzle spraying
the gas to the surface of the substrate wet with the deionized
water, a second nozzle spraying the gas to the surface of the
substrate, a nozzle arm fixedly provided with the first nozzle and
the second nozzle and a moving element moving the nozzle arm in a
plane substantially parallel to the substrate, while the moving
element moves the nozzle arm to spray the gas from the second
nozzle to the same region as the region on the substrate sprayed
with the gas by the first nozzle.
[0012] The second nozzle sprays the gas to the same region as that
on the substrate sprayed with the gas by the first nozzle, whereby
the substrate processing apparatus can also completely remove a
trace of moisture remaining on the surface of the substrate for
stably and reliably drying the surface of the substrate.
[0013] According to another aspect of the present invention, the
substrate processing apparatus comprises a nozzle spraying the gas
to the surface of the substrate wet with the deionized water, a
nozzle arm fixedly provided with the nozzle and a moving element
moving the nozzle arm in a plane parallel to the substrate, while
the moving element moves the nozzle arm to re-spray the gas from
the nozzle to the same region as the region on the substrate
sprayed with the gas by the nozzle.
[0014] The nozzle re-sprays the gas to the same region as that on
the substrate sprayed with the gas by the nozzle, whereby the
substrate processing apparatus can also completely remove a trace
of moisture remaining on the surface of the substrate for stably
and reliably drying the surface of the substrate.
[0015] The present invention is also directed to a substrate
processing method spraying gas to a substrate completely cleaned
with deionized water for drying the substrate.
[0016] Accordingly, an object of the present invention is to
provide a substrate processing apparatus and a substrate processing
method capable of stably and reliably drying the surface of a
substrate.
[0017] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a longitudinal sectional view showing the
structure of a substrate processing apparatus according to a first
embodiment of the present invention;
[0019] FIG. 2 illustrates movement of a first gas nozzle and a
second gas nozzle in a horizontal plane;
[0020] FIG. 3 illustrates the first gas nozzle starting discharging
nitrogen gas;
[0021] FIG. 4 illustrates the second gas nozzle located immediately
above the rotation center of a substrate W;
[0022] FIG. 5 illustrates a process of movement of the first gas
nozzle and the second gas nozzle moving from immediately above the
rotation center of the substrate toward the edge;
[0023] FIG. 6 illustrates the second gas nozzle located immediately
above the edge of the substrate;
[0024] FIG. 7 is a longitudinal sectional view showing the
structure of a substrate processing apparatus according to a second
embodiment of the present invention;
[0025] FIG. 8 illustrates movement of a first gas nozzle and a
second gas nozzle of the substrate processing apparatus according
to the second embodiment in a horizontal plane; and
[0026] FIG. 9 is a longitudinal sectional view showing the
structure of a substrate processing apparatus according to a third
embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] Embodiments of the present invention are now described in
detail with reference to the drawings.
1. First Embodiment
[0028] FIG. 1 is a longitudinal sectional view showing the
structure of a substrate processing apparatus according to a first
embodiment of the present invention. The substrate processing
apparatus according to the first embodiment is a single-substrate
type substrate processing apparatus performing cleaning processing
etc. on a substrate W, and mainly comprises a spin base 10 holding
the substrate W, a plurality of chuck pins 14 provided on the spin
base 10, an electric motor 20 rotating the spin base 10, a
processing solution nozzle 30 and a gas nozzle 40 provided above
the spin base 10, a splash guard 50 enclosing the substrate W held
by the spin base 10, a mechanism supplying a processing solution
and gas to the substrate W held on the spin base 10 and a mechanism
vertically moving the splash guard 50.
[0029] The spin base 10 substantially horizontally holds the
substrate W thereon. This spin base 10 is a discoidal member having
an opening on its center, and provided on its upper surface with
the plurality of chuck pins 14 grasping the peripheral edge of the
circular substrate W respectively. The spin base 10 may be provided
with at least three chuck pins 14, in order to reliably hold the
circular substrate W. FIG. 1 shows only two chuck pins 14 for
convenience of illustration.
[0030] Each of the chuck pins 14 comprises a substrate support part
14a supporting the peripheral edge of the substrate W from below
and a substrate holding part 14b pressing the outer peripheral end
surface of the substrate W supported by the substrate support part
14a for holding the substrate W. Each chuck pin 14 is switchable
between a pressing state where the substrate holding part 14b
presses the outer peripheral end surface of the substrate W and an
open state where the substrate holding part 14b separates from the
outer peripheral end surface of the substrate W. In order to switch
the plurality of chuck pins 14 between the pressing state and the
open state, the substrate processing apparatus may employ any known
mechanism such as a link mechanism rotating the plurality of chuck
pins 14 in an interlocking manner, for example.
[0031] In order to transfer or receive the substrate W to or from
the spin base 10, the substrate processing apparatus brings the
chuck pins 14 into the open state. In order to perform processing
described later on the substrate W, on the other hand, the
substrate processing apparatus brings the chuck pins 14 into the
pressing state. When brought into the pressing state, the plurality
of chuck pins 14 grasp the peripheral edge of the substrate W for
horizontally holding the substrate W at a prescribed interval from
the spin base 10. The substrate W is held in a state directing the
front and rear surfaces thereof upward and downward respectively.
When the chuck pins 14 are brought into the pressing state for
holding the substrate W, the upper ends of the substrate holding
parts 14b project upward beyond the upper surface of the substrate
W, in order to reliably hold the substrate W so that the same will
not fall from the chuck pins 14 in processing.
[0032] A rotary shaft 11 is suspended from the lower surface of the
center of the spin base 10. This rotary shaft 11 is a hollow
cylindrical member, and a lower processing solution nozzle 15 is
inserted into the inner hollow portion thereof. The electric motor
20 is interlocked/coupled with a portion close to the lower end of
the rotary shaft 11 through a belt drive mechanism 21. In other
words, a belt 21c is extended between an idler pulley 21a fixedly
provided on the outer periphery of the rotary shaft 11 and a
driving pulley 21b coupled to the rotation axis of the electric
motor 20. The driving force of the electric motor 20 is transmitted
to the rotary shaft 11 through the belt drive mechanism 21 for
rotating the rotary shaft 11, the spin base 10 and the substrate W
held by the same about an axis J along the vertical direction in a
horizontal plane.
[0033] The lower processing solution nozzle 15 passes through the
rotary shaft 11, so that its forward end 15a is located immediately
under the center of the substrate W held by the spin base 10. The
base end of the lower processing solution nozzle 15 is
communicatively connected to a processing solution pipe 16. The
base end of the processing solution pipe 16 is bifurcated into
branch pipes 16a and 16b communicatively connected with a chemical
solution supply source 17 and a deionized water supply source 18
respectively. The branch pipes 16a and 16b are provided with valves
12a and 12b provided. The substrate processing apparatus can
selectively switch and discharge/supply a chemical solution or
deionized water from the forward end 15a of the lower processing
solution nozzle 15 to a portion around the center of the lower
surface of the substrate W held by the spin base 10 by switching
opening/closing of the valves 12a and 12b. In other words, the
substrate processing apparatus can supply the chemical solution
from the lower processing solution nozzle 15 by opening the valve
12a and closing the valve 12b, and can supply the deionized water
from the lower processing solution nozzle 15 by opening the valve
12b and closing the valve 12a. The substrate processing apparatus
uses hydrofluoric acid (HF), hydrochloric acid (HCl), SC2 (mixed
solution of hydrochloric acid, hydrogen peroxide water and water)
or the like, for example, as the chemical solution.
[0034] A clearance between the inner walls of the hollow portion of
the rotary shaft 11 and the opening of the spin base 10 and the
outer wall of the lower processing solution nozzle 15 defines a gas
supply passage 19. A forward end 19a of the gas supply passage 19
is directed to the center of the lower surface of the substrate W
held by the spin base 10. The base end of the gas supply passage 19
is communicatively connected to a gas pipe 22. The gas pipe 22 is
communicatively connected to an inert gas supply source 23, while a
valve 13 is provided on an intermediate portion of the path of the
gas pipe 22. The substrate processing apparatus can supply inert
gas from the forward end 19a of the gas supply passage 19 to the
center of the lower surface of the substrate W held by the spin
base 10 by opening the valve 13. The substrate processing apparatus
uses nitrogen gas (N.sub.2), for example, as the inert gas.
[0035] The rotary shaft 11, the belt drive mechanism 21, the
electric motor 20 etc. described above are stored in a cylindrical
casing 25 provided on a base member 24.
[0036] A receiving member 26 is fixedly mounted on the periphery of
the casing 25 provided on the base member 24. Cylindrical partition
members 27a, 27b and 27c are uprightly provided on the base member
24 as the receiving member 26. A space between the outer wall of
the casing 25 and the inner wall of the partition member 27a forms
a first discharge tank 28, a space between the outer wall of the
partition member 27a and the inner wall of the partition member 27b
forms a second discharge tank 29 and a space between the outer wall
of the partition member 27b and the inner wall of the partition
member 27c forms a third discharge tank 39.
[0037] An outlet 28a communicatively connected to a disposal drain
28b is provided on the bottom of the first discharge tank 28. Spent
deionized water and gas are discharged from the outlet 28a of the
first discharge tank 28 to the disposal drain 28b. The deionized
water and the gas discharged to the disposal drain 28b are
separated from each other and thereafter disposed according to
prescribed procedures respectively.
[0038] An outlet 29a communicatively connected to a discharge drain
29b is provided on the bottom of the second discharge tank 29. A
spent chemical solution is discharged from the outlet 29a of the
second discharge tank 29 to the discharge drain 29b. The chemical
solution discharged to the discharge drain 29b is discharged to a
discharge line (not shown).
[0039] An outlet 39a communicatively connected to a recovery drain
39b is provided on the bottom of the third discharge tank 39.
Another spent chemical solution is discharged from the outlet 39a
of the third discharge tank 39 to the recovery drain 39b. The
chemical solution discharged to the recovery drain 39b is recovered
by a recovery tank (not shown) so that the recovered chemical
solution is supplied from the recovery tank to the chemical
solution supply source 17 to be circulated/recycled.
[0040] The splash guard 50 is provided above the receiving member
26. The splash guard 50 is a cylindrical member, which is arranged
to enclose the spin base 10 and the substrate W held by the same.
The splash guard 50 is formed by an outer side portion 54 and an
inner side portion 55. The outer side portion 54 and the inner side
portion 55 are coupled with each other by a coupling member 56,
which is only partially arranged for circumferentially forming a
discharge guide channel. A clearance between the outer side portion
54 and the inner side portion 55 coupled with each other by the
coupling member 56 forms a recovery port 57, whose diameter is
reduced upward. The inner side portion 55 of the splash guard 50 is
formed with a first receiving part 51 having a V-shaped section and
a second receiving part 52 having an arcuate section, and provided
with annular grooves 53a and 53b.
[0041] The splash guard 50 is coupled with a guard moving mechanism
59 through a link member 58, and rendered vertically movable by the
guard moving mechanism 59. The guard moving mechanism 59 can be
formed by any known mechanism such as a feed screw mechanism
employing a ball screw or a mechanism employing an air
cylinder.
[0042] When the guard moving mechanism 59 moves down the splash
guard 50 to the lowermost position, the partition members 27a and
27b are loosely fitted with the grooves 53a and 53b while the upper
end of the splash guard 50 is located downward beyond the spin base
10 and the substrate W held by the same so that the substrate W is
introducible. When the guard moving mechanism 59 thereafter
slightly moves up the splash guard 50, the recovery port 57 is
located around the substrate W (the state shown in FIG. 1). The
substrate processing apparatus implements this state in etching
processing for recovering/recycling the chemical solution, so that
the chemical solution scattered from the rotated substrate W etc.
is received by the recovery port 57, passes through the coupling
member 56, flows into the third discharge tank 39, is guided to the
outlet 39a and thereafter discharged from the outlet 39a to the
recovery drain 39b.
[0043] When the guard moving mechanism 59 slightly moves up the
splash guard 50 from the state shown in FIG. 1, it follows that the
first receiving part 51 is located around the spin base 10 and the
substrate W held by the same. The substrate processing apparatus
implements this state in deionized water rinse processing, so that
the deionized water scattered from the rotated substrate W etc. is
received by the first receiving part 51, flows into the first
discharge tank 28 along its inclination, is guided to the outlet
28a and thereafter discharged from the outlet 28a to the disposal
drain 28b.
[0044] When the guard moving mechanism 59 further moves up the
splash guard 50, it follows that the partition members 27a and 27b
separate from the grooves 53a and 53b respectively while the second
receiving part 52 is located around the spin base 10 and the
substrate W held by the same. The substrate processing apparatus
implements this state in etching processing for disposing the
chemical solution, so that the chemical solution scattered from the
rotated substrate W etc. is received by the second receiving part
52, flows into the second discharge tank 29 along its curved
surface, is guided to the outlet 29a and thereafter discharged from
the outlet 29a to the discharge drain 29b.
[0045] The processing solution nozzle 30 is provided above the spin
base 10. The processing solution nozzle 30 is fixed to the forward
end of a nozzle arm 31 while directing its discharge port 30a
vertically downward. The base end of the nozzle arm 31 is coupled
to the rotation axis of a rotary motor 32. The rotary motor 32
rotates the nozzle arm 31 and the processing solution nozzle 30 in
a horizontal plane.
[0046] A nozzle moving mechanism (not shown) renders the rotary
motor 32 vertically movable. Therefore, the processing solution
nozzle 30 performs rotation about the rotation axis of the rotary
motor 32 in the horizontal plane and vertical movement. Due to such
operations, the processing solution nozzle 30 is movable between a
position (discharge position) located above the rotation center of
the substrate W held by the spin base 10 and an upper position
(retreating position) outside the splash guard 50.
[0047] The processing solution nozzle 30 is communicatively
connected to a processing solution pipe 33. The base end of the
processing solution pipe 33 is bifurcated into branch pipes 33a and
33b communicatively connected with the chemical solution supply
source 17 and the deionized water supply source 18 respectively.
The branch pipes 33a and 33b are provided with valves 34a and 34b.
The substrate processing apparatus can selectively switch and
discharge/supply the chemical solution or the deionized water from
the discharge port 30a of the processing solution nozzle 30 to the
upper surface of the substrate W held by the chuck pins 14 by
switching opening/closing of the valves 34a and 34b. In other
words, the substrate processing apparatus can supply the chemical
solution from the processing solution nozzle 30 by opening the
valve 34a and closing the valve 34b, and can supply the deionized
water from the processing solution nozzle 30 by opening the valve
34b and closing the valve 34a.
[0048] The processing nozzle 30 may be formed not by a single
nozzle but by a chemical solution nozzle dedicated to the chemical
solution and a deionized water nozzle dedicated to the deionized
water.
[0049] A gas nozzle 40 is also provided above the spin base 10.
This gas nozzle 40 is formed by a first gas nozzle 41 and a second
gas nozzle 42. The first gas nozzle 41 is fixed to a portion around
the forward end of the nozzle arm 43 while directing its discharge
port 41a vertically downward. The second gas nozzle 42 is also
fixed to a portion around the forward end of the nozzle arm 43
while directing its discharge port 42a vertically downward. In
other words, the first and second gas nozzles 41 and 42 are fixed
to the same nozzle arm 43. The base end of the nozzle arm 43 is
coupled to the rotation axis of a rotary motor 48. The rotary motor
48 rotates the first and second gas nozzles 41 and 42 and the
nozzle arm 34 in a horizontal plane.
[0050] A nozzle moving mechanism (not shown) renders the rotary
motor 48 vertically movable. The nozzle moving mechanism vertically
moves the rotary motor 48, thereby vertically moving the first and
second gas nozzle 41 and 42 and the nozzle arm 43 coupled to the
rotary motor 48. Therefore, the first and second gas nozzles 41 and
42 perform rotation about the rotation axis of the rotary motor 48
in the horizontal plane and vertical movement. Due to such
operations, the first and second gas nozzles 41 and 42 are movable
between a position (discharge position) located above the rotation
center of the substrate W held by the spin base 10 and an upper
position (retreating position) outside the splash guard 50.
[0051] FIG. 2 shows the first and second gas nozzles 41 and 42
moved in the horizontal plane. As hereinabove described, the
substrate W is rotated by the electric motor 20 about the vertical
axis J in the horizontal plane. On the other hand, the first and
second gas nozzles 41 and 42 are rotated by the rotary motor 48
about a vertical axis X in the horizontal plane. The first and
second gas nozzles 41 and 42 are fixed to the nozzle arm 43
equidistantly from the axis X. As shown in FIG. 2, therefore, both
of the first and second gas nozzles 41 and 42 rotated by the rotary
motor 48 draw a locus R directed from the rotation center of the
substrate W toward the edge.
[0052] Both of the first and second nozzles 41 and 42 are
communicatively connected to an inert gas supply source 46. In
other words, the forward end of a gas pipe 47 is communicatively
connected to the inert gas supply source 46 while the base end
thereof is bifurcated into branch pipes 47a and 47b communicatively
connected to the first and second gas nozzles 41 and 42
respectively. The branch pipe 47a is provided with a valve 44a and
a flow control valve 45a. The branch pipe 47b is provided with a
valve 44b and a flow control valve 45b.
[0053] The substrate processing apparatus can switch
presence/absence of discharge of inert gas (e.g., nitrogen gas)
from the respective discharge ports 41a and 42a of the first and
second gas nozzles 41 and 42 by opening/closing the valves 44a and
44b. In other words, the substrate processing apparatus can
discharge and spray the nitrogen gas from the discharge port 41a of
the first gas nozzle 41 to the upper surface of the substrate W
held by the chuck pins 14 by opening the valve 44a. Similarly, the
substrate processing apparatus can discharge and spray the nitrogen
gas from the discharge port 42a of the second gas nozzle 42 to the
upper surface of the substrate W held by the chuck pins 14 by
opening the valve 44b. When opening both of the valves 44a and 44b,
the substrate processing apparatus can discharge the nitrogen gas
from both of the first and second gas nozzles 41 and 42, as a
matter of course.
[0054] The flow control valves 45a and 45b have functions of
adjusting the flow rates of the nitrogen gas passing through the
respective ones of the branch pipes 47a and 47b for controlling the
flow rates of the nitrogen gas discharged from the respective ones
of the first and second gas nozzles 41 and 42.
[0055] A drying control part 90 controls operations of the valves
44a and 44b, the flow control valves 45a and 45b, the rotary motor
48 and the electric motor 20. The drying control part 90 is formed
by a computer comprising a CPU, a memory and the like, so that the
CPU runs a prescribed processing program thereby controlling the
operations of the valves 44a and 44b, the flow control valves 45a
and 45b, the rotary motor 48 and the electric motor 20.
[0056] The respective ones of the first and second gas nozzles 41
and 42 are fixed to the portions around the forward end of the
nozzle arm 43 while directing the discharge ports 41a and 42a
vertically downward. Therefore, it follows that the nitrogen gas is
discharged from the respective ones of the first and second nozzles
41 and 42 vertically downward. Both of the first and second gas
nozzles 41 and 42 rotated by the rotary motor 48 draw the locus R
directed from the rotation center (the axis J) of the substrate W
toward the edge. Therefore, it follows that the rotary motor 48
rotates the nozzle arm 43 so that arrival points of the gas
discharged from the respective ones of the first and second gas
nozzles 41 and 42 draw the locus R directed from the rotation
center of the rotated substrate W toward the edge.
[0057] The procedure of the substrate processing apparatus
according to the first embodiment having the aforementioned
structure for the substrate W is now described. In summary, the
single-substrate type substrate processing apparatus according to
the first embodiment performs etching processing on the substrate W
with the chemical solution (dilute hydrofluoric acid), thereafter
performs rinse processing for washing out the chemical solution
with the deionized water, and thereafter performs drying processing
on the substrate W.
[0058] First, the substrate processing apparatus slightly moves
down the splash guard 50 thereby protruding the spin base 10 from
the splash guard 50 and moving the processing solution nozzle 30
and the gas nozzle 40 to the retreating positions. In this state, a
transport robot (not shown) transfers the unprocessed substrate W
to the spin base 10. The chuck pins 14 grasp the peripheral edge of
the transferred substrate W thereby horizontally holding the
substrate W.
[0059] Then, the thermal processing apparatus moves up the splash
guard 50 for locating the recovery port 57 around the spin base 10
and the substrate W held by the same while moving the processing
solution nozzle 30 to the position located above the rotation
center of the substrate W. Then, the thermal processing apparatus
rotates the spin base 10 as well as the substrate W held by the
same. In this state, the lower processing solution nozzle 15
discharges the chemical solution (dilute hydrofluoric acid) to the
lower surface of the substrate W while the processing solution
nozzle 30 also discharges the chemical solution to the upper
surface of the substrate W. In other words, the substrate
processing apparatus supplies the chemical solution to the front
and rear surfaces of the rotated substrate W for progressing
etching processing. In this etching processing, the gas supply
passage 19 may discharge a small quantity of nitrogen gas for
preventing the chemical solution from backwardly flowing into the
gas supply passage 19.
[0060] In the etching processing, the chemical solution scattered
from the rotated substrate W is received by the recovery port 57 of
the splash guard 50, passes through the coupling member 56 and
flows into the third discharge tank 39. The chemical solution
flowing into the third discharge tank 39 is discharged from the
outlet 39a to the recovery drain 39b and recovered.
[0061] When the chemical solution may not be recovered, the
substrate processing apparatus moves up the splash guard 50 for
locating the second receiving part 52 around the spin base 10 and
the substrate W held by the same. The chemical solution received by
the second receiving part 52 flows into the second discharge tank
29, and is discharged from the outlet 29a to the discharge drain
29b.
[0062] After completion of the etching processing performed for a
prescribed time, the substrate processing apparatus stops
discharging the chemical solution from the lower processing
solution nozzle 15 and the processing solution nozzle 30 and moves
up the splash guard 50 for locating the first receiving part 51
around the spin base 10 and the substrate W held by the same. The
processing solution nozzle 30 remains on the position located above
the rotation center of the substrate W. In this state, the
processing solution nozzle 30 and the lower processing solution
nozzle 15 discharge the deionized water to the upper and lower
surfaces of the rotated substrate W. The discharged deionized water
spreads entirely over the front and rear surfaces of the substrate
W due to centrifugal force of rotation, to progress cleaning
processing (rinse processing) for washing out the chemical solution
with the deionized water. Also in the rinse processing, the gas
supply passage 19 may discharge a small quantity of nitrogen gas
for preventing the deionized water from backwardly flowing into the
gas supply passage 19.
[0063] In the rinse processing, the deionized water scattered from
the rotated substrate W is received by the first receiving part 51
of the splash guard 50 and flows into the first discharge tank 28
along its inclination. The deionized water flowing into the first
discharge tank 28 is discharged from the outlet 28a to the disposal
drain 28b.
[0064] After completion of the rinse processing performed for a
prescribed time, the substrate processing apparatus stops
discharging the deionized water from the processing solution nozzle
30 and the lower processing solution nozzle 15 and slightly moves
down the splash guard 50 for slightly protruding the spin base 10
from the splash guard 50. In consideration of prevention of water
marks, it is preferable to reduce the rotational frequency for the
substrate W immediately before stopping discharging the deionized
water for paddling the deionized water on the upper surface of the
substrate W before completing the rinse processing.
[0065] The substrate processing apparatus moves the processing
solution nozzle 30 to the retreating position while moving the gas
nozzle 40 to the position located above the rotation center of the
substrate W. At this time, the drying control part 90 controls the
rotary motor 48 for locating the first gas nozzle 41 immediately
above the rotation center of the substrate W (above the axis J). In
drying processing described later, the drying control part 90
controls operations of the valves 44a and 44b, the flow control
valves 45a and 45b, the rotary motor 48 and the electric motor
20.
[0066] After locating the first gas nozzle 41 immediately above the
rotation center of the substrate W, the substrate processing
apparatus starts discharging the nitrogen gas from the first gas
nozzle 41 while starting rotating the first gas nozzle 41 along the
locus R (see FIG. 2) directed from immediately above the rotation
center of the substrate W toward the edge. At this time, the
substrate processing apparatus rotates the spin base 10 along with
the substrate W held by the same. In this stage, the second gas
nozzle 42 discharges no gas.
[0067] FIG. 3 shows the first gas nozzle 41 starting discharging
the nitrogen gas. The substrate processing apparatus sprays the
nitrogen gas to the rotation center of the substrate W from the
first gas nozzle 41 while rotating the substrate W thereby
expelling moisture from the rotation center toward the edge. The
substrate processing apparatus moves the first gas nozzle 41
discharging the nitrogen gas toward the edge of the substrate W
along the locus R thereby increasing the expelled area of the
substrate W. Such an expelled area is substantially circularly
shaped as viewed from above due to the continuous rotation of the
substrate W.
[0068] It is important to expel moisture by gradually ejecting the
deionized water heaped on the substrate W toward the edge by
centrifugal force resulting from rotation of the substrate W and
discharge of the nitrogen gas from the first gas nozzle 41, and it
is unpreferable to abruptly expel the moisture. This is because the
moisture may scatter and re-adhere to the substrate W to newly
cause imperfect drying if abruptly expelled. In order to implement
such gentle moisture expulsion, the rotational frequency for the
substrate W is relatively lowly set to 10 rpm to 360 rpm, desirably
set to 20 rpm to 260 rpm in the drying processing. Further, the
flow rate for discharging the nitrogen gas from the first gas
nozzle 41 is set to at least 5 l/min., desirably 10 l/min. to 80
l/min. In addition, the traveling speed of the first gas nozzle 41
along the locus R is set to 3 mm/sec. to 200 mm/sec., desirably 6
mm/sec. to 150 mm/sec. when the diameter of the substrate W is
.phi.200 mm.
[0069] The first and second gas nozzles 41 and 42 fixed to the same
nozzle arm 43 are simultaneously rotated along the locus R.
Therefore, the second gas nozzle 42 reaches the position
immediately above the rotation center of the substrate W,
immediately after the first gas nozzle 41 starts moving from the
position immediately above the rotation center of the substrate W.
When reaching the position immediately above the rotation center of
the substrate W, the second gas nozzle 42 starts discharging the
nitrogen gas.
[0070] FIG. 4 shows the second gas nozzle 42 located immediately
above the rotation center of the substrate W. The second gas nozzle
42 sprays the nitrogen gas to the area, already expelled by the
nitrogen gas sprayed from the first gas nozzle 41, around the
rotation center of the substrate W. In the area expelled by the
nitrogen gas sprayed from the first gas nozzle 41, moisture
infiltrating into a clearance of a fine pattern or the like may not
be readily dried but remain in a trace. The substrate processing
apparatus can also completely expel such a trace of moisture
remaining on the fine pattern or the like by spraying the nitrogen
gas from the second gas nozzle 42 to the aforementioned area.
[0071] In other words, the nitrogen gas discharge from the first
gas nozzle 41 and that discharged from the second gas nozzle 42
have different roles, such that the first gas nozzle 41 discharges
the nitrogen gas in order to loosely expel visible moisture and the
second gas nozzle 42 discharges the nitrogen gas in order to
completely remove a trace of moisture remaining on the fine pattern
or the like. Therefore, the flow rate of the nitrogen gas sprayed
from the second gas nozzle 42 to the substrate W is larger than
that of the nitrogen gas sprayed from the first gas nozzle 41 to
the substrate W. More specifically, the flow rate of the nitrogen
gas discharged from the second gas nozzle 42 is set to at least 5
l/min., desirably at least 20 l/min. to 200 l/min. The substrate
processing apparatus continuously discharges the nitrogen gas from
the first gas nozzle 41 also after starting discharging the
nitrogen gas from the second gas nozzle 42, for continuously
expelling the moisture heaped on the substrate W. The substrate
processing apparatus also continuously rotates the substrate W and
moves the first and second gas nozzles 41 and 42 toward the edge of
the substrate W along the locus R.
[0072] FIG. 5 illustrates the process of movement of the first and
second gas nozzles 41 and 42 from immediately above the rotation
center of the substrate W toward the edge. The substrate processing
apparatus rotates the nozzle arm 43 while discharging the nitrogen
gas from both of the first and second gas nozzles 41 and 42,
thereby gradually expelling the moisture remaining on the substrate
W toward the edge due to the nitrogen gas sprayed from the first
gas nozzle 41 and immediately eliminating a small quantity of
residual moisture from the expelled area due to the nitrogen gas
sprayed from the second gas nozzle 42.
[0073] When the first gas nozzle 41 reaches a position located
immediately above the edge of the substrate W, the substrate
processing apparatus stops discharging the nitrogen gas from the
first gas nozzle 41. At this time, the substrate processing
apparatus has expelled visible moisture from above the substrate W.
The substrate processing apparatus continuously discharges the
nitrogen gas from the second gas nozzle 42 and rotating the nozzle
arm 43 and the substrate W.
[0074] Thereafter the second gas nozzle 42 immediately reaches the
position located immediately above the edge of the substrate W.
FIG. 6 illustrates the second gas nozzle 42 located immediately
above the edge of the substrate W. When the second gas nozzle 42
reaches the position immediately above the substrate W, the
substrate processing apparatus stops discharging the nitrogen gas
from the second gas nozzle 42. At this point, the substrate
processing apparatus also completely removes a trace of moisture
remaining on the overall upper surface of the substrate W.
[0075] Thereafter the substrate processing apparatus further
increases the rotational frequency for the substrate W for
performing finish drying. At this time, the rotational frequency
for the substrate W is set to a high level of 800 rpm to 4000 rpm,
desirably 1000 rpm to 3000 rpm.
[0076] When the finish drying processing performed for a prescribed
time is completed, the substrate processing apparatus stops
rotating the spin base 10 and the substrate W held by the same. The
substrate processing apparatus further moves the processing
solution nozzle 30 and the gas nozzle 40 to the retreating
positions. At this time, the transport robot (not shown) takes out
and discharges the processed substrate W from the spin base 10,
thereby terminating the series of processing.
[0077] As hereinabove described, the substrate processing apparatus
can also completely remove a trace of moisture remaining on the
fine pattern or the like by loosely expelling visible moisture from
the substrate W by spraying the nitrogen gas from the first gas
nozzle 41 and thereafter spraying the nitrogen gas from the second
gas nozzle 42 to the same region of the substrate W as that sprayed
with the nitrogen gas by the first gas nozzle 41. Consequently, it
is possible to quickly and completely remove moisture adhering to
the surface of the substrate W without using IPA, for stably and
reliably drying the surface of the substrate W.
[0078] In order to stably and reliably dry the surface of the
substrate W by spraying the nitrogen gas to the same region twice,
the interval between the first spraying and the second spraying is
preferably minimized. If this interval is long, a trace of moisture
remaining on the fine pattern or the like causes imperfect drying.
According to the first embodiment, the first and second gas nozzles
41 and 42 are fixed to the same nozzle arm 43, whereby the interval
between the first spraying and the second spraying depends on the
rotational speed of the nozzle arm 43 and the distance between the
first and second gas nozzles 41 and 42. The rotational speed of the
nozzle arm 43 (traveling speed of the first gas nozzle 41 along the
locus R) is described above. While the distance between the first
and second gas nozzles 41 and 42 is preferably minimized in
consideration of prevention of water marks, discharged nitrogen gas
components may mutually interfere with each other to cause
turbulence if the nozzles 41 and 42 are too close to each other.
Under the aforementioned conditions, therefore, the distance
between the first and second gas nozzles 41 and 42 is set to about
10 mm to 30 mm.
[0079] The substrate processing apparatus clearly distinguishes the
first and second gas nozzles 41 and 42 into the role of discharging
the nitrogen gas for loosely expelling visible moisture and the
role of discharging the nitrogen gas for completely removing a
trace of moisture remaining on the fine pattern or the like
respectively, to be capable of stabilizing drying processing and
allowing process conditions (discharge flow rate etc.) in each
nozzle some latitude.
[0080] Further, the substrate processing apparatus renders the flow
rate of the nitrogen gas sprayed from the second gas nozzle 42 to
the substrate W larger than that of the nitrogen gas sprayed from
the first gas nozzle 41 to the substrate W thereby ensuring gradual
expulsion of visible moisture and complete removal of moisture
remaining in a trace.
[0081] In addition, the substrate processing apparatus rotates the
substrate W while the arrival point of the nitrogen gas discharged
from each of the first and second gas nozzles 41 and 42 draws the
locus R directed from the rotation center of the substrate W toward
the edge, whereby it follows that each of the first and second gas
nozzles 41 and 42 sprays the nitrogen gas to the overall surface of
the substrate W so that the substrate processing apparatus can
stably and reliably dry the overall surface of the substrate W.
2. Second Embodiment
[0082] A second embodiment of the present invention is now
described. FIG. 7 is a longitudinal sectional view showing the
structure of a substrate processing apparatus according to the
second embodiment. Referring to FIG. 7, members identical to those
of the substrate processing apparatus according to the first
embodiment are denoted by the same reference numerals, to omit
redundant description. The structure of the substrate processing
apparatus according to the second embodiment is different from that
of the substrate processing apparatus according to the first
embodiment in a set mode of a gas nozzle 40, and the remaining
points of the former are identical to those of the latter. While
FIG. 7 shows no processing solution nozzle 30 for convenience of
illustration, the substrate processing apparatus according to the
second embodiment has a processing solution nozzle 30 similar to
that in the substrate processing apparatus according to the first
embodiment.
[0083] The gas nozzle 40 is formed by a first gas nozzle 41 and a
second gas nozzle 42, which are fixed to different nozzle arms 43a
and 43b respectively in the second embodiment. The first gas nozzle
41 is fixed to a portion close to the forward end of the nozzle arm
43a while directing its discharge port 41a vertically downward. The
base end of the nozzle arm 43a is coupled to the rotation axis of a
rotary motor 48a. The rotary motor 48a rotates the first gas nozzle
41 and the nozzle arm 43a in a horizontal plane.
[0084] A nozzle moving mechanism (not shown) renders the rotary
motor 48a vertically movable. The nozzle moving mechanism
vertically moves the rotary motor 48a, thereby also vertically
moving the first gas nozzle 41 and the nozzle arm 43a coupled to
the rotary motor 48a. Therefore, the first gas nozzle 41 performs
rotation in the horizontal plane about the rotation axis of the
rotary motor 48a and vertical movement. Due to such operations, the
first gas nozzle 41 is movable between a position (discharge
position) located above the rotation center of a substrate W held
by a spin base 10 and an upper position (retreating position)
outside a splash guard 50.
[0085] On the other hand, the second gas nozzle 42 is fixed to a
portion close to the forward end of the nozzle arm 43b while
directing its discharge port 42a vertically downward. The base end
of the nozzle arm 43b is coupled to the rotation axis of a rotary
motor 48b. The rotary motor 48b rotates the second gas nozzle 42
and the nozzle arm 43b in a horizontal plane.
[0086] Another nozzle moving mechanism (not shown) also renders the
rotary motor 48b vertically movable. The nozzle moving mechanism
vertically moves the rotary motor 48b, thereby also vertically
moving the second gas nozzle 42 and the nozzle arm 43b coupled to
the rotary motor 48b. Therefore, the second gas nozzle 42 performs
rotation in the horizontal plane about the rotation axis of the
rotary motor 48b and vertical movement. Due to such operations, the
second gas nozzle 42 is also movable between the position
(discharge position) located above the rotation center of the
substrate W held by the spin base 10 and the upper position
(retreating position) outside the splash guard 50.
[0087] FIG. 8 illustrates movement of the first and second gas
nozzles 41 and 42 according to the second embodiment in the
horizontal plane. Similarly to the first embodiment, an electric
motor 20 rotates the substrate W about a vertical axis J in the
horizontal plane. On the other hand, the rotary motors 48a and 48b
rotate the first and second gas nozzles 41 and 42 in the horizontal
plane about vertical axes X1 and X2 respectively. Both of the first
and second gas nozzles 41 and 42 are rotated to pass through the
rotation center of the substrate W. In other words, the first gas
nozzle 41 rotated by the rotary motor 48a draws a locus R1 directed
from the rotation center (axis J) of the substrate W toward the
edge while the second gas nozzle 42 rotated by the rotary motor 48b
draws another locus R2 directed from the rotation center of the
substrate W toward the edge, as shown in FIG. 8.
[0088] The first and second gas nozzles 41 and 42 are
communicatively connected to inert gas supply sources 46a and 46b
respectively. In other words, the forward end of a gas pipe 49a is
communicatively connected to the inert gas supply source 46a while
its base end is communicatively connected to the first gas nozzle
41. Similarly, the forward end of a gas pipe 49b is communicatively
connected to the inert gas supply source 46b while its base end is
communicatively connected to the second gas nozzle 42. The gas pipe
49a is provided with a valve 44a and a flow control valve 45a. The
gas pipe 49b is provided with a valve 44b and a flow control valve
45b.
[0089] The substrate processing apparatus can switch
presence/absence of discharge of inert gas (e.g., nitrogen gas)
from the discharge ports 41a and 42a of the first and second gas
nozzles 41 and 42 by opening/closing the valves 44a and 44b. In
other words, the substrate processing apparatus can discharge and
spray the nitrogen gas from the discharge port 41a of the first gas
nozzle 41 to the upper surface of the substrate W held by chuck
pins 14 by opening the valve 44a. Similarly, the substrate
processing apparatus can discharge and spray the nitrogen gas from
the discharge port 42a of the second gas nozzle 42 to the upper
surface of the substrate W held by the chuck pins 14 by opening the
valve 44b. When opening both of the valves 44a and 44b, the
substrate processing apparatus can discharge the nitrogen gas from
both of the first and second gas nozzles 41 and 42, as a matter of
course.
[0090] The flow control valves 45a and 45b have functions of
adjusting the flow rates of the nitrogen gas passing through the
gas pipes 49a and 49b respectively thereby controlling the flow
rates of the nitrogen gas discharged from the first and second gas
nozzles 41 and 42 respectively. Similarly to the first embodiment,
a drying control part 90 controls operations of the valves 44a and
44b, the flow control valves 45a and 45b, the rotary motors 48a and
48b and the electric motor 20.
[0091] The respective ones of the first and second gas nozzles 41
and 42 are fixed to the portions close to the forward ends of the
nozzle arms 43a and 43b while directing the discharge ports 41a and
42a vertically downward. Therefore, it follows that the respective
ones of the first and second gas nozzles 41 and 42 discharge the
nitrogen gas vertically downward. Further, the first and second gas
nozzles 41 and 42 rotated by the rotary motors 48a and 48b
respectively draw the loci R1 and R2 both directed from the
rotation center (axis J) of the substrate W toward the edge.
Therefore, it follows that the rotary motors 48a and 48b rotate the
nozzle arms 43a and 43b respectively so that arrival points of the
gas discharged from the respective ones of the first and second gas
nozzles 41 and 42 draw the loci R1 and R2 directed from the
rotation center of the rotated substrate W toward the edge.
[0092] Thus, it follows that the first and second gas nozzles 41
and 42 are rotated mutually independently of each other according
to the second embodiment. A procedure of the substrate processing
apparatus according to the second embodiment for the substrate W is
now described. The outline of the procedure in the single-substrate
type substrate processing apparatus according to the second
embodiment is to perform etching processing with a chemical
solution (dilute hydrofluoric acid) on the substrate W, thereafter
perform rinse processing of washing out the chemical solution with
deionized water and thereafter perform drying processing of the
substrate W, similarly to the first embodiment. The processing up
to the rinse processing is absolutely identical to that in the
first embodiment, and hence redundant description is omitted.
[0093] After completion of the rinse processing, the substrate
processing apparatus moves the processing solution nozzle 30 to the
retreating position while the rotary motor 48a rotates the nozzle
arm 43a to locate the first gas nozzle 41 on the position
immediately above the rotation center (axis J) of the substrate
W.
[0094] After locating the first gas nozzle 41 immediately above the
rotation center of the substrate W, the substrate processing
apparatus starts discharging the nitrogen gas from the first gas
nozzle 41 while starting rotating the first gas nozzle 41 along the
locus R1 from immediately above the rotation center of the
substrate W toward the edge. At this time, the substrate processing
apparatus rotates the spin base 10 and the substrate W held by the
same.
[0095] The substrate processing apparatus sprays the nitrogen gas
to the rotation center of the substrate W from the first gas nozzle
41 while rotating the substrate W, thereby expelling moisture from
the rotation center toward the edge. The substrate processing
apparatus moves the first gas nozzle 41 discharging the nitrogen
gas toward the edge of the substrate W along the locus R1, thereby
increasing the expelled area of the substrate W. Such an expelled
area is substantially circularly shaped as viewed from above due to
continuous rotation of the substrate W.
[0096] Also in the second embodiment, the first gas nozzle 41 plays
the role of gradually ejecting visible moisture remaining on the
substrate W toward the edge, similarly to that in the first
embodiment. Therefore, the substrate processing apparatus sets the
rotational frequency for the substrate W, the traveling speed of
the first gas nozzle 41 and the flow rate of the nitrogen gas
discharged from the first gas nozzle 41 similarly to those in the
first embodiment.
[0097] According to the second embodiment, the substrate processing
apparatus drives the first and second gas nozzles 41 and 42
independently of each other while the rotary motor 48b rotates the
nozzle arm 43b to locate the second gas nozzle 42 immediately above
the rotation center of the substrate W immediately after the
substrate processing apparatus starts moving the first gas nozzle
41 from immediately above the rotation center of the substrate W.
When locating the second gas nozzle 42 immediately above the
rotation center of the substrate W, the substrate processing
apparatus starts discharging the nitrogen gas from the second gas
nozzle 42 while simultaneously starting rotating the second gas
nozzle 42 from immediately above the rotation center of the
substrate W to the edge along the locus R2. In order to prevent the
first and second gas nozzles 41 and 42 from interference, the
substrate processing apparatus preferably rotates the first and
second gas nozzles 41 and 42 oppositely through the rotation center
of the substrate W. Further, the substrate processing apparatus
equalizes the traveling speeds of the first and second gas nozzles
41 and 42 to each other while substantially equalizing the flow
rate of the nitrogen gas discharged from the second gas nozzle 42
to that in the first embodiment.
[0098] The substrate processing apparatus sprays the nitrogen gas
from the second gas nozzle 42 to the area, already expelled by the
nitrogen gas sprayed from the first gas nozzle 41, around the
rotation center of the substrate W. Thus, the substrate processing
apparatus can also completely remove a trace of moisture remaining
on a fine pattern or the like, similarly to the first
embodiment.
[0099] Also in the second embodiment, the nitrogen gas discharge
from the first gas nozzle 41 and that from the second gas nozzle 42
have different roles, such that the first gas nozzle 41 discharges
the nitrogen gas in order to loosely expel visible moisture while
the second gas nozzle 42 discharges the nitrogen gas in order to
completely remove a trace of moisture remaining on the fine pattern
or the like. Therefore, the flow rate of the nitrogen gas sprayed
from the second gas nozzle 42 to the substrate W is larger than
that of the nitrogen gas sprayed from the first gas nozzle 41 to
the substrate W. The substrate processing apparatus continuously
discharges the nitrogen gas from the first gas nozzle 41 also after
starting discharging the nitrogen gas from the second gas nozzle
42, for continuously expelling the moisture heaped on the substrate
W. The substrate processing apparatus also continuously rotates the
substrate W and moves the first and second gas nozzles 41 and 42
toward the edge of the substrate W along the loci R1 and R2
respectively.
[0100] Thus, the substrate processing apparatus sprays the gas from
the second gas nozzle 42 to the area of the substrate W already
sprayed with the nitrogen gas by the first gas nozzle 41, thereby
gradually expelling the moisture remaining on the substrate W
toward the edge due to the nitrogen gas sprayed from the first gas
nozzle 41 and immediately removing a trace of residual moisture
from the expelled area due to the nitrogen gas sprayed from the
second gas nozzle 42.
[0101] When the first gas nozzle 41 reaches a portion immediately
above the edge of the substrate W, the substrate processing
apparatus stops discharging the nitrogen gas from the first gas
nozzle 41. At this time, the substrate processing apparatus expels
visible moisture from the substrate W. Thereafter the second gas
nozzle 42 immediately reaches the portion immediately above the
edge of the substrate W. When the second gas nozzle 42 reaches the
portion immediately above the edge of the substrate W, the
substrate processing apparatus stops discharging the nitrogen gas
from the second gas nozzle 42. At this point of time, the substrate
processing apparatus also completely removes moisture remaining in
a trace from the overall upper surface of the substrate W.
[0102] Thereafter the substrate processing apparatus further
increases the rotational frequency for the substrate W for
performing finish drying. The subsequent procedure is identical to
that in the first embodiment.
[0103] Effects similar to those of the first embodiment can be
attained also in the aforementioned manner, while the substrate
processing apparatus according to the second embodiment can reduce
the distance between the rotation center of the substrate W and the
first and second gas nozzles 41 and 42 without causing mutual
interference between the flows of the nitrogen gas discharged from
the first and second gas nozzles 41 and 42. Thus, the substrate
processing apparatus can further narrow the time interval between
first spraying and second spraying for further stably and reliably
drying the surface of the substrate W.
3. Third Embodiment
[0104] A third embodiment of the present invention is now
described. FIG. 9 is a longitudinal sectional view showing the
structure of a substrate processing apparatus according to the
third embodiment. Referring to FIG. 9, members identical to those
of the substrate processing apparatus according to the first
embodiment are denoted by the same reference numerals, to omit
redundant description. The structure of the substrate processing
apparatus according to the third embodiment is different from that
of the substrate processing apparatus according to the first
embodiment in a set mode of a gas nozzle 40, and the remaining
points of the former are identical to those of the latter.
[0105] According to the third embodiment, the gas nozzle 40 is
formed by a single nozzle. The gas nozzle 40 is fixed to a portion
close to the forward end of a nozzle arm 43 while directing its
discharge port 40a vertically downward. The base end of the nozzle
arm 43 is coupled to the rotation axis of a rotary motor 48. The
rotary motor 48 rotates the gas nozzle 40 and the nozzle arm 43 in
a horizontal plane.
[0106] A nozzle moving mechanism (not shown) renders the rotary
motor 48 vertically movable. The nozzle moving mechanism vertically
moves the rotary motor 48, thereby also vertically moving the gas
nozzle 40 and the nozzle arm 43 coupled to the rotary motor 48.
Therefore, the gas nozzle 40 performs rotation in the horizontal
plane about the rotation axis of the rotary motor 48 and vertical
movement. Due to such operations, the gas nozzle 40 is also movable
between a position (discharge position) located above the rotation
center of a substrate W held by a spin base 10 and an upper
position (retreating position) outside a splash guard 50.
[0107] The mode of movement of the gas nozzle 40 in the horizontal
plane is identical to that in the first embodiment (see FIG. 2). In
other words, an electric motor 20 rotates the substrate W in the
horizontal plane about an axis J along the vertical direction. On
the other hand, the rotary motor 48 rotates the gas nozzle 40 in
the horizontal plane about an axis along the vertical direction.
The gas nozzle 40 rotated by the rotary motor 48 draws a locus
directed from the rotation center (axis J) of the substrate W
toward the edge.
[0108] The gas nozzle 40 is communicatively connected to an inert
gas supply source 46. In other words, the forward end of a gas pipe
47 is communicatively connected to the inert gas supply source 46,
while its base end is communicatively connected to the gas nozzle
40. The gas pipe 47 is provided with a valve 44 and a flow control
valve 45.
[0109] The substrate processing apparatus can switch
presence/absence of discharge of inert gas (e.g., nitrogen gas)
from the discharge port 40a of the gas nozzle 40 by opening/closing
the valve 44. In other words, the substrate processing apparatus
can discharge and spray the nitrogen gas from the discharge port
40a of the gas nozzle 40 to the upper surface of the substrate W
held by chuck pins 41 by opening the valve 44.
[0110] The flow control valve 45 has a function of adjusting the
flow rate of the nitrogen gas passing through the gas pipe 47 for
controlling the flow rate of the nitrogen gas discharged from the
gas nozzle 40. A drying control part 90 controls operations of the
valve 44, the flow control valve 45, the rotary motor 48 and the
electric motor 20, similarly to the first embodiment.
[0111] The gas nozzle 40 is fixed to the portion around the forward
end of the nozzle arm 43 while directing the discharge port 40a
vertically downward. Therefore, it follows that the gas nozzle 40
discharges the nitrogen gas vertically downward. Further, the gas
nozzle 40 rotated by the rotary motor 48 draws the locus directed
from the rotation center (axis J) of the substrate W toward the
edge. Therefore, it also follows that the rotary motor 48 rotates
the nozzle arm 43 so that the arrival point of the gas discharged
from the gas nozzle 40 draws a locus directed from the rotation
center of the rotated substrate W toward the edge.
[0112] Thus, it follows that the substrate processing apparatus
according to the third embodiment rotates the single gas nozzle 40.
The procedure of the substrate processing apparatus according to
the third embodiment on the substrate W is now described. The
outline of the procedure in the single-substrate type substrate
processing apparatus according to the third embodiment is to
perform etching processing with a chemical solution (dilute
hydrofluoric acid) on the substrate W, thereafter perform rinse
processing of washing out the chemical solution with deionized
water and thereafter perform drying processing of the substrate W,
similarly to the first embodiment. The processing up to the rinse
processing is absolutely identical to that in the first embodiment,
and hence redundant description is omitted.
[0113] After completion of the rinse processing, the substrate
processing apparatus moves a processing solution nozzle 30 to a
retreating position while the rotary motor 48 rotates the nozzle
arm 43 to locate the gas nozzle 40 on the position immediately
above the rotation center (axis J) of the substrate W.
[0114] After locating the gas nozzle 40 immediately above the
rotation center of the substrate W, the substrate processing
apparatus starts discharging the nitrogen gas from the gas nozzle
40 while starting rotating the gas nozzle 40 along the
aforementioned locus directed from immediately above the rotation
center of the substrate W toward the edge. At this time, the
substrate processing apparatus rotates the spin base 10 and the
substrate W held by the same.
[0115] The substrate processing apparatus sprays the nitrogen gas
from the gas nozzle 40 to the rotation center of the substrate W
while rotating the substrate W, thereby expelling moisture from the
rotation center toward the edge. The substrate processing apparatus
moves the gas nozzle 40 discharging the nitrogen gas from the
position immediately above the rotation center of the substrate W
toward the edge thereby increasing the expelled area of the
substrate W. Such an expelled area is substantially circularly
shaped as viewed from above due to the continuous rotation of the
substrate W. Also in the third embodiment, the gas nozzle 40 plays
a role of gradually ejecting visible moisture remaining on the
substrate W toward the edge and loosely expelling the same by
discharging the nitrogen gas at this time, similarly to that in the
first embodiment.
[0116] When the gas nozzle 40 reaches a portion immediately above
the edge of the substrate W, the substrate processing apparatus
temporarily stops discharging the nitrogen gas from the gas nozzle
40. At this time, the substrate processing apparatus has expelled
visible moisture from the substrate W. Thereafter the rotary motor
48 immediately rotates the nozzle arm 43 to re-locate the gas
nozzle 40 immediately above the rotation center of the substrate W.
When locating the gas nozzle 40 immediately above the rotation
center of the substrate W, the substrate processing apparatus
immediately restarts discharging the nitrogen gas from the gas
nozzle 40 while secondly starting rotating the gas nozzle 40 along
the aforementioned locus directed from the portion immediately
above the rotation center of the substrate W toward the edge. At
this time, the substrate processing apparatus continuously rotates
the spin base 10 and the substrate W held by the same.
[0117] The substrate processing apparatus sprays the nitrogen gas
from the gas nozzle 40 to the upper surface of the substrate W,
i.e., the area already expelled by first nitrogen spraying from the
gas nozzle 40. Thus, the substrate processing apparatus can also
completely remove a trace of moisture remaining on a fine pattern
or the like similarly to the first embodiment.
[0118] Thus, first nitrogen gas discharging and second nitrogen gas
discharging from the gas nozzle 40 have different roles in the
third embodiment, such that the first nitrogen gas discharging is
performed for loosely expelling visible moisture and the second
nitrogen gas discharging aims at completely removing a trace of
moisture remaining on the fine pattern or the like. Therefore, the
flow rate of the nitrogen gas secondly sprayed from the gas nozzle
40 to the substrate W is larger than that of the nitrogen gas
firstly sprayed from the gas nozzle 40 to the substrate W.
[0119] When the gas nozzle 40 reaches the portion immediately above
the edge of the substrate W, the substrate processing apparatus
stops discharging the nitrogen gas from the gas nozzle 40. At this
time, the substrate processing apparatus also completely removes
moisture remaining in a trace from the overall upper surface of the
substrate W.
[0120] Thereafter the substrate processing apparatus further
increases the rotational frequency for the substrate W for
performing finish drying. The subsequent procedure is identical to
that of the first embodiment.
[0121] Effects similar to those of the first embodiment can be
attained also in the aforementioned manner, while the structure of
the substrate processing apparatus can be simplified due to the
drying processing performed by the single gas nozzle 40. In
consideration of reduction of the time interval between the first
nitrogen gas spraying and the second spraying, however, it is
preferable to provide two gas nozzles similarly to each of the
aforementioned first and second embodiments.
4. MODIFICATIONS
[0122] While the embodiments of the present invention have been
described, the present invention is not restricted to the
aforementioned examples. For example, while each of the substrate
processing apparatuses according to the aforementioned embodiments
employs nitrogen gas as the inert gas, the inert gas is not
restricted to the nitrogen gas but another inert gas (e.g., helium)
may alternatively be employed. Further, the gas nozzle(s) may
discharge gas such as air in place of the inert gas. However, it is
preferable to use the inert gas poor in reactivity, in order to
attain an excellent drying result. Further, it is necessary to use
sufficiently normalized clean air when spraying air to a
semiconductor substrate formed with a fine pattern or the like.
[0123] The respective ones of the first and second gas nozzles 41
and 42 are not restricted to the mode of fixation to the nozzle arm
43 while directing the discharge ports 41a and 42a vertically
downward, but the same may alternatively be fixed to the nozzle arm
43 in inclined postures.
[0124] While the substrate processing apparatus according to each
of the aforementioned embodiments performs all of chemical solution
processing, deionized water rinse processing and drying processing,
it is also possible to transfer a substrate W subjected to chemical
solution processing and deionized water rinse processing in another
apparatus to the substrate processing apparatus according to each
of the aforementioned embodiments for thereafter performing
additional deionized rinse processing and drying processing.
[0125] While the invention has been shown and described in detail,
the foregoing description is in all aspects illustrative and not
restrictive. It is therefore understood that numerous modifications
and variations can be devised without departing from the scope of
the invention.
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