U.S. patent application number 12/219838 was filed with the patent office on 2009-02-12 for rinsing method and developing method.
Invention is credited to Ryouichirou Naitou, Takeshi Shimoaoki.
Application Number | 20090042149 12/219838 |
Document ID | / |
Family ID | 35783673 |
Filed Date | 2009-02-12 |
United States Patent
Application |
20090042149 |
Kind Code |
A1 |
Naitou; Ryouichirou ; et
al. |
February 12, 2009 |
Rinsing method and developing method
Abstract
A rinsing process is performed by supplying a rinsing-liquid
onto a substrate with a light-exposed pattern formed thereon and
treated by a developing process. The rinsing liquid contains a
polyethylene glycol family surfactant or an acetylene glycol family
surfactant in a critical micelle concentration or less. Preferably,
the surfactant includes a hydrophobic group having a carbon number
of larger than 11 and having no double bond or triple bond
therein.
Inventors: |
Naitou; Ryouichirou;
(Kikuchi-gun, JP) ; Shimoaoki; Takeshi;
(Kikuchi-gun, JP) |
Correspondence
Address: |
SMITH, GAMBRELL & RUSSELL
1130 CONNECTICUT AVENUE, N.W., SUITE 1130
WASHINGTON
DC
20036
US
|
Family ID: |
35783673 |
Appl. No.: |
12/219838 |
Filed: |
July 29, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11652497 |
Jan 12, 2007 |
7419773 |
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12219838 |
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PCT/JP2005/010068 |
Jun 1, 2005 |
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11652497 |
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Current U.S.
Class: |
430/331 |
Current CPC
Class: |
G03F 7/40 20130101; H01L
21/67051 20130101 |
Class at
Publication: |
430/331 |
International
Class: |
G03F 7/20 20060101
G03F007/20 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 14, 2004 |
JP |
JP 2004-207574 |
Claims
1-6. (canceled)
7. A developing method for developing a light-exposed pattern,
after a resist film formed on a substrate is subjected to light
exposure with a predetermined pattern, the method comprising:
applying a developing solution onto the resist film disposed on the
substrate after the light exposure, and performing development;
throwing off the developing solution from the substrate after the
development; supplying a rinsing liquid onto the substrate, wherein
the rinsing liquid contains a polyethylene glycol family surfactant
in a critical micelle concentration or less, and the surfactant
includes a hydrophobic group having a carbon number of larger than
11 and including only single bonds and excluding double and triple
bonds; supplying purified water onto the substrate to replace the
rinsing liquid present on the substrate with purified water; and
rotating the substrate to expand purified water on the substrate,
and to throw off purified water to dry the substrate.
8. The developing method according to claim 7, wherein the
surfactant contained in the rinsing liquid has a molecular weight
of 1,280 or more.
9. The developing method according to claim 7, wherein supplying
the rinsing liquid onto the substrate uses a nozzle configured to
deliver the rinsing liquid essentially as a belt, and comprises
moving the nozzle for scanning above the substrate, or setting the
nozzle above the substrate to be directed in a radial direction of
the substrate and rotating the substrate at a predetermined
rotation number, while delivering the rinsing liquid essentially as
a belt from the nozzle.
10. A developing method for developing a light-exposed pattern,
after a resist film formed on a substrate is subjected to light
exposure with a predetermined pattern, the method comprising:
applying a developing solution onto the resist film disposed on the
substrate after the light exposure, and performing development;
throwing off the developing solution from the substrate after the
development; supplying purified water onto the substrate, supplying
a rinsing liquid onto the substrate to replace purified water
present on the substrate with the rinsing liquid, wherein the
rinsing liquid contains a polyethylene glycol family surfactant in
a critical micelle concentration or less, and the surfactant
includes a hydrophobic group having a carbon number of larger than
11 and including only single bonds and excluding double and triple
bonds; and rotating the substrate to expand the rinsing liquid on
the substrate, and to throw off the rinsing liquid to dry the
substrate.
11. The developing method according to claim 10, wherein the
surfactant contained in the rinsing liquid has a molecular weight
of 1,280 or more.
12. The developing method according to claim 10, wherein supplying
the rinsing liquid onto the substrate uses a nozzle configured to
deliver the rinsing liquid essentially as a belt, and comprises
moving the nozzle for scanning above the substrate, or setting the
nozzle above the substrate to be directed in a radial direction of
the substrate and rotating the substrate at a predetermined
rotation number, while delivering the rinsing liquid essentially as
a belt from the nozzle.
13. A developing method for developing a light-exposed pattern,
after a resist film formed on a substrate is subjected to light
exposure with a predetermined pattern, the method comprising:
applying a developing solution onto the resist film disposed on the
substrate after the light exposure, and performing development;
throwing off the developing solution from the substrate after the
development; supplying purified water onto the substrate, supplying
a rinsing liquid onto the substrate to replace purified water
present on the substrate with the rinsing liquid, wherein the
rinsing liquid contains a polyethylene glycol family surfactant in
a critical micelle concentration or less, and the surfactant
includes a hydrophobic group having a carbon number of larger than
11 and including only single bonds and excluding double and triple
bonds; supplying purified water onto the substrate to replace the
rinsing liquid present on the substrate with purified water; and
rotating the substrate to expand purified water on the substrate,
and to throw off purified water to dry the substrate.
14. The developing method according to claim 13, wherein the
surfactant contained in the rinsing liquid has a molecular weight
of 1,280 or more.
15. The developing method according to claim 13, wherein supplying
the rinsing liquid onto the substrate uses a nozzle configured to
deliver the rinsing liquid essentially as a belt, and comprises
moving the nozzle for scanning above the substrate, or setting the
nozzle above the substrate to be directed in a radial direction of
the substrate and rotating the substrate at a predetermined
rotation number, while delivering the rinsing liquid essentially as
a belt from the nozzle.
16. A developing method for developing a light-exposed pattern,
after a resist film formed on a substrate is subjected to light
exposure with a predetermined pattern, the method comprising:
applying a developing solution onto the resist film disposed on the
substrate after the light exposure, and performing development;
throwing off the developing solution from the substrate after the
development; supplying a rinsing liquid onto the substrate, wherein
the rinsing liquid contains a polyethylene glycol family surfactant
in a critical micelle concentration or less, and the surfactant
includes a hydrophobic group having a carbon number of larger than
11 and including only single bonds and excluding double and triple
bonds; throwing off the rinsing liquid from the substrate; applying
a developing solution onto the substrate again, and performing
development; throwing off the developing solution from the
substrate after the development; supplying purified water onto the
substrate; and rotating the substrate to expand purified water on
the substrate, and to throw off purified water to dry the
substrate.
17. The developing method according to claim 16, wherein the
surfactant contained in the rinsing liquid has a molecular weight
of 1,280 or more.
18. The developing method according to claim 16, wherein supplying
the rinsing liquid onto the substrate uses a nozzle configured to
deliver the rinsing liquid essentially as a belt, and comprises
moving the nozzle for scanning above the substrate, or setting the
nozzle above the substrate to be directed in a radial direction of
the substrate and rotating the substrate at a predetermined
rotation number, while delivering the rinsing liquid essentially as
a belt from the nozzle.
19. A developing method for developing a light-exposed pattern,
after a resist film formed on a substrate is subjected to light
exposure with a predetermined pattern, the method comprising:
supplying a rinsing liquid onto the substrate, wherein the rinsing
liquid contains a polyethylene glycol family surfactant in a
critical micelle concentration or less, and the surfactant includes
a hydrophobic group having a carbon number of larger than 11 and
including only single bonds and excluding double and triple bonds;
throwing off the rinsing liquid from the substrate to dry the
substrate; applying a developing solution onto the substrate, and
performing development of the resist film; throwing off the
developing solution from the substrate after the development;
supplying purified water onto the substrate; and rotating the
substrate to expand purified water on the substrate, and to throw
off purified water to dry the substrate.
20. The developing method according to claim 19, wherein the
surfactant contained in the rinsing liquid has a molecular weight
of 1,280 or more.
21. The developing method according to claim 19, wherein supplying
the rinsing liquid onto the substrate uses a nozzle configured to
deliver the rinsing liquid essentially as a belt, and comprises
moving the nozzle for scanning above the substrate, or setting the
nozzle above the substrate to be directed in a radial direction of
the substrate and rotating the substrate at a predetermined
rotation number, while delivering the rinsing liquid essentially as
a belt from the nozzle.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a rinsing method for
performing a rinsing process on a substrate, such as a
semiconductor wafer, after a developing process is performed on a
light-exposed pattern formed thereon, and a developing method
including such a rinsing process.
[0003] 2. Description of the Related Art
[0004] For example, in the process of manufacturing semiconductor
devices, a so-called photolithography technique is used. According
to this photolithography technique, a resist liquid is applied onto
the surface of a semiconductor wafer (which will be referred to as
"wafer") to form a resist film. Then, the resist film is subjected
to a light exposure process in accordance with a predetermined
pattern. Then, the resist film with the light-exposed pattern thus
formed is subjected to a developing process.
[0005] In the developing process used as one of the steps of the
photolithography technique, a developing solution is supplied onto
the wafer to form a developing solution puddle. Then, this state is
held for a predetermined time to promote the developing process by
natural convection. Thereafter, the developing solution is thrown
off, and purified water is then supplied as a cleaning liquid to
wash out the developing solution remaining on the wafer. Then, the
wafer is rotated at a high speed to throw off the developing
solution and cleaning liquid remaining on the wafer, thereby drying
the wafer.
[0006] In recent years, circuit structures of semiconductor devices
are increasingly miniaturized with advances in light exposure
techniques and so forth, and thus resist patterns with a smaller
size and a higher aspect ratio have come into use. Accordingly, a
problem arises such that resist patterns are pulled and bent by a
surface tension of a rinsing liquid, i.e., so-called "pattern fall"
is caused, when the rinsing liquid is being removed from the gaps
between the patterns during a throwing-off/drying operation at the
end of the developing step described above.
[0007] As a technique to solve this problem, Jpn. Pat. Appln. KOKAI
Publication No. 7-142349 discloses a proposed technique such that,
for example, a surfactant solution is mixed into a rinsing liquid
to decrease the surface tension of the rinsing liquid. Further,
Jpn. Pat. Appln. KOKAI Publication No. 2001-5191 discloses a
process in which a surfactant is supplied when a rinsing process is
performed on a substrate after a developing process.
[0008] Unlike the conventional process using purified water,
however, where a surfactant is used together with a rinsing liquid,
a problem arises such that the surfactant generates particles and
contaminates the wafer. In other words, the wafer suffers
precipitation defects due to the surfactant, which deteriorate the
quality. Further, another problem arises such that the surfactant
dissolves resist patterns, and/or the surfactant causes CD
(Critical Dimension) fluctuations. However, so far, optimum process
conditions in light of these problems have not yet been found to
rinsing processes using a surfactant.
BRIEF SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide a rinsing
method and developing method that can suppress generation of
precipitation defects in a developing process. An alternative
object of the present invention is to provide a rinsing method and
developing method that can suppress the CD fluctuation. A further
alternative object of the present invention is to provide a rinsing
method and developing method that can suppress dissolution of
resist patterns due to a rinsing liquid.
[0010] The following aspects are conceived to solve the problem
described above. According to a first aspect of the present
invention, there is provided a rinsing method for performing a
rinsing process, the method comprising: supplying a rinsing liquid
onto a substrate with a light-exposed pattern formed thereon and
treated by a developing process, wherein the rinsing liquid
contains a polyethylene glycol family surfactant or an acetylene
glycol family surfactant in a critical micelle concentration or
less, and the surfactant includes a hydrophobic group having a
carbon number of larger than 11 and having no double bond or triple
bond therein.
[0011] According to a second aspect of the present invention, there
is provided a rinsing method for performing a rinsing process, the
method comprising: supplying a rinsing liquid onto a substrate with
a light-exposed pattern formed thereon and treated by a developing
process, wherein the rinsing liquid contains a polyethylene glycol
family surfactant or an acetylene glycol family surfactant, and the
surfactant includes a hydrophobic group having a carbon number of
larger than 11 and having no double bond or triple bond
therein.
[0012] In the rinsing method according to the first or second
aspect, the polyethylene glycol family surfactant is preferably any
one of polyethylene glycol sorbitan fatty acid ester, polyethylene
glycol straight-chain alkyl ester, polyethylene glycol fatty acid
ester, straight-chain alkyl addition type polyethylene glycol
phenyl ester, and branched-chain alkyl addition type polyethylene
glycol phenyl ester, and the acetylene glycol family surfactant is
preferably EO addition type acetylene glycol.
[0013] Supplying the rinsing liquid onto the substrate preferably
uses a nozzle configured to deliver the rinsing liquid essentially
as a belt, and preferably comprises moving the nozzle for scanning
above the substrate, while delivering the rinsing liquid
essentially as a belt from the nozzle, or setting the nozzle above
the substrate to be directed in a radial direction of the substrate
and rotating the substrate at a predetermined rotation number,
while delivering the rinsing liquid essentially as a belt from the
nozzle.
[0014] The present invention further provides a developing method
using such a rinsing method. According to a third aspect of the
present invention, there is provided a developing method for
developing a light-exposed pattern, after a resist film formed on a
substrate is subjected to light exposure with a predetermined
pattern, the method comprising:
[0015] applying a developing-solution onto the resist film disposed
on the substrate after the light exposure, and performing
development;
[0016] throwing off the developing solution from the substrate
after the development;
[0017] supplying a rinsing liquid onto the substrate, the rinsing
liquid containing a polyethylene glycol family surfactant or an
acetylene glycol family surfactant in a critical micelle
concentration or less, and the surfactant including a hydrophobic
group having a carbon number of larger than 11 and having no double
bond or triple bond therein;
[0018] supplying purified water onto the substrate to replace the
rinsing liquid present on the substrate with purified water;
and
[0019] rotating the substrate to expand purified water on the
substrate, and to throw off purified water to dry the
substrate.
[0020] According to a fourth aspect of the present invention, there
is provided a developing method for developing a light-exposed
pattern, after a resist film formed on a substrate is subjected to
light exposure with a predetermined pattern, the method
comprising:
[0021] applying a developing solution onto the resist film disposed
on the substrate after the light exposure, and performing
development;
[0022] throwing off the developing solution from the substrate
after the development;
[0023] supplying purified water onto the substrate,
[0024] supplying a rinsing liquid onto the substrate to replace
purified water present on the substrate with the rinsing liquid,
the rinsing liquid containing a polyethylene glycol family
surfactant or an acetylene glycol family surfactant in a critical
micelle concentration or less, and the surfactant including a
hydrophobic group having a carbon number of larger than 11 and
having no double bond or triple bond therein; and
[0025] rotating the substrate to expand the rinsing liquid on the
substrate, and to throw off the rinsing liquid to dry the
substrate.
[0026] According to a fifth aspect of the present invention, there
is provided a developing method for developing a light-exposed
pattern, after a resist film formed on a substrate is subjected to
light exposure with a predetermined pattern, the method
comprising:
[0027] applying a developing solution onto the resist film disposed
on the substrate after the light exposure, and performing
development;
[0028] throwing off the developing solution from the substrate
after the development;
[0029] supplying purified water onto the substrate,
[0030] supplying a rinsing liquid onto the substrate to replace
purified water present on the substrate with the rinsing liquid,
the rinsing liquid containing a polyethylene glycol family
surfactant or an acetylene glycol family surfactant in a critical
micelle concentration or less, and the surfactant including a
hydrophobic group having a carbon number of larger than 11 and
having no double bond or triple bond therein;
[0031] supplying purified water onto the substrate to replace the
rinsing liquid present on the substrate with purified water;
and
[0032] rotating the substrate to expand purified water on the
substrate, and to throw off purified water to dry the
substrate.
[0033] According to a sixth aspect of the present invention, there
is provided a developing method for developing a light exposed
pattern, after a resist film formed on a substrate is subjected to
light exposure with a predetermined pattern, the method
comprising:
[0034] applying a developing solution onto the resist film disposed
on the substrate after the light exposure, and performing
development;
[0035] throwing off the developing solution from the substrate
after the development;
[0036] supplying a rinsing liquid onto the substrate, the rinsing
liquid containing a polyethylene glycol family surfactant or an
acetylene glycol family surfactant in a critical micelle
concentration or less, and the surfactant including a hydrophobic
group having a carbon number of larger than 11 and having no double
bond or triple bond therein;
[0037] throwing off the rinsing liquid from the substrate;
[0038] applying a developing solution onto the substrate again, and
performing development;
[0039] throwing off the developing solution from the substrate
after the development;
[0040] supplying purified water onto the substrate; and
[0041] rotating the substrate to expand purified water on the
substrate, and to throw off purified water to dry the
substrate.
[0042] According to a seventh aspect of the present invention,
there is provided a developing method for developing a
light-exposed pattern, after a resist film formed on a substrate is
subjected to light exposure with a predetermined pattern, the
method comprising:
[0043] supplying a rinsing liquid onto the substrate, the rinsing
liquid containing a polyethylene glycol family surfactant or an
acetylene glycol family surfactant in a critical micelle
concentration or less, and the surfactant including a hydrophobic
group having a carbon number of larger than 11 and having no double
bond or triple bond therein;
[0044] throwing off the rinsing liquid from the substrate to dry
the substrate;
[0045] applying a developing solution onto the substrate, and
performing development of the resist film;
[0046] throwing off the developing solution from the substrate
after the development;
[0047] supplying purified water onto the substrate; and
[0048] rotating the substrate to expand purified water on the
substrate, and to throw off purified water to dry the
substrate.
[0049] Also in each of these developing methods, the surfactant
contained in the rinsing liquid preferably has a molecular weight
of 1,280 or more. Further, the polyethylene glycol family
surfactant or acetylene glycol family surfactant consists
preferably of a material as one of those described above. The
rinsing liquid is preferably supplied by the method described
above.
[0050] According to the present invention, since a rinsing process
is performed while using a surfactant-containing rinsing liquid, it
is possible to suppress generation of precipitation defects, such
as particles. Further, it is possible to suppress the CD
fluctuation and dissolution of resist patterns. It follows that
resist patterns can be formed with high precision. As a matter of
course, the present invention can solve a problem concerning
pattern fall.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0051] FIG. 1 is a plan view schematically showing the structure of
a developing apparatus;
[0052] FIG. 2 is a sectional view schematically showing the
structure of the developing apparatus;
[0053] FIG. 3 is a view schematically showing the structure of a
liquid supply system used in the developing apparatus;
[0054] FIG. 4 is a graph showing the relationship between
surfactant concentrations and surface tension where surfactants
containing hydrophobic groups with different structures were
respectively dissolved into purified water;
[0055] FIG. 5 is a graph showing CD fluctuations where aqueous
solutions respectively containing surfactants A to E were used for
performing a rinsing process after a developing process;
[0056] FIG. 6 is a graph showing the number of precipitation
defects, such as particles, where aqueous solutions respectively
containing surfactants were used for performing a rinsing process
after a developing process;
[0057] FIG. 7 is a graph showing the relationship between
surfactant molecular weights and CD fluctuations where aqueous
solutions respectively containing surfactants were used for
performing a rinsing process after a developing process;
[0058] FIG. 8 is a graph showing the relationship between
surfactant molecular weights and the number of precipitation
defects where aqueous solutions respectively containing surfactants
were used for performing a rinsing process after a developing
process;
[0059] FIG. 9 is a graph showing CD fluctuations where aqueous
solutions respectively containing surfactants C and D in a
concentration of 100 ppm were used for performing a rinsing process
after a developing process;
[0060] FIG. 10 is a graph showing the number of precipitation
defects where aqueous solutions respectively containing surfactants
C and D in a concentration of 100 ppm were used for performing a
rinsing process after a developing process;
[0061] FIG. 11 is a flowchart showing a first developing
process;
[0062] FIG. 12 is a flowchart showing a second developing process;
and
[0063] FIGS. 13A to 13F are views schematically showing the first
to sixth developing processes.
DETAILED DESCRIPTION OF THE INVENTION
[0064] Embodiments of the present invention will now be described
with reference to the accompanying drawings.
[0065] FIG. 1 is a plan view schematically showing the structure of
a developing apparatus, and FIG. 2 is a sectional view thereof. In
the following description, two directions perpendicular to each
other in the horizontal plane are denoted as an X-direction and a
Y-direction, and the vertical direction is denoted as a
Z-direction, as shown in FIGS. 1 and 2.
[0066] This developing apparatus (DEV) includes a casing 1 provided
with a fan and filter unit F at the ceiling thereof to form a
downflow of clean air in the casing. An annular cup CP is disposed
at the center in the casing 1, and a spin chuck 2 is disposed
inside the cup CP. The spin chuck 2 is arranged to fix and hold a
wafer W by means of vacuum suction. The spin chuck 2 is operated to
rotate by a drive motor 3 disposed below the spin chuck 2. The
drive motor 3 is attached to a bottom plate 4.
[0067] Lifter pins 5 used for transferring the wafer W are disposed
inside the cup CP and are movable up and down by a driving
mechanism 6, such as an air cylinder. Further, a drain port 7 used
for waste liquid is formed inside the cup CP. The drain port 7 is
connected to a waste liquid tube 8, which extends through a space N
between the bottom plate 4 and casing 1, as shown in FIG. 1, and is
connected to a waste liquid port (not shown) located below.
[0068] A sidewall of the casing 1 has an opening la formed therein
that allows a transfer arm T of a wafer transfer unit to pass
therethrough. The opening la is opened and closed by a shutter 9.
When the wafer W is loaded/unloaded, the shutter 9 is opened, and
the transfer arm T comes into the casing 1. The wafer W is
transferred between the transfer arm T and the spin chuck 2, while
the lifter pins 5 are present at the upper position.
[0069] A developing solution nozzle 11, a purified water nozzle 12,
and a rinsing liquid nozzle 13 are disposed above the cup CP, such
that each of them is movable between a supply position above the
wafer W and a waiting position outside the wafer W. The developing
solution nozzle 11 is used for supplying a developing solution onto
the surface of the wafer W. The purified water nozzle 12 is used
for supplying a water-based cleaning liquid onto the wafer W after
the development. The rinsing liquid nozzle 13 is used for supplying
a rinsing liquid comprising purified water with a surfactant
dissolved therein. In the following explanation, the water-based
cleaning liquid is purified water (DIW), as an example.
[0070] The developing solution nozzle 11 has an elongated shape and
is disposed such that the longitudinal direction of the elongated
shape is horizontal. The developing solution nozzle 11 has a
plurality of delivery ports on the bottom face to deliver the
developing solution as a belt as a whole. The developing solution
nozzle 11 is detachably attached to the distal end of a first
nozzle scan arm 14 by a holding member 15a. The first nozzle scan
arm 14 is attached to the upper end of a first vertical support
member 22, which stands up in a vertical direction from a first
guide rail 21 extending in the Y direction on the bottom plate 4.
The developing solution nozzle 11 is horizontally movable together
with the first vertical support member 22 in the Y-direction by a
Y-axis driving mechanism 23. Further, the first vertical support
member 22 is movable up and down by a Z-axis driving mechanism 24,
so that the developing solution nozzle 11 can be moved between a
delivery position closer to the wafer W and a non-delivery position
on the upper side by an up-and-down movement of the first vertical
support member 22.
[0071] When the developing solution is applied onto the wafer W,
the developing solution nozzle 11 is placed at a position above the
wafer W. Then, while the developing solution is delivered as a belt
from the developing solution nozzle 11, the wafer W is rotated by
180.degree. or more, such as 360.degree.. Consequently, the
developing solution is applied all over the surface of the wafer W
to form a developing solution puddle. Alternatively, when the
developing solution is delivered, the developing solution nozzle 11
may be moved along the first guide rail 21 for scanning without
rotating the wafer W.
[0072] The purified water nozzle 12 is formed of a nozzle of the
straight type. The purified water nozzle 12 is detachably attached
to the distal end of a second nozzle scan arm 16. A second guide
rail 25 is disposed on the bottom plate 4 at a position outside the
first guide rail 21. The second nozzle scan arm 16 is attached
through an X-axis driving mechanism 29 to the upper end of a second
vertical support member 26, which stands up in a vertical direction
from the second guide rail 25. Consequently, the purified water
nozzle 12 is horizontally movable together with the second vertical
support member 26 in the Y-direction by a Y-axis driving mechanism
27. Further, the second vertical support member 26 is movable up
and down by a Z-axis driving mechanism 28, so that the purified
water nozzle 12 can be moved between a delivery position closer to
the wafer W and a non-delivery position on the upper side by an
up-and-down movement of the second vertical support member 26.
Furthermore, the second nozzle scan arm 16 is movable in the
X-direction by the X-axis driving mechanism 29, so that the
purified water nozzle 12 is also movable in the X-direction. The
shape of the purified water nozzle 12 is not limited to a specific
one. The nozzle 12 may have an elongated shape with a number of
delivery ports formed therein, as in the developing solution nozzle
11. Alternatively, the nozzle 12 may be formed of a slit nozzle
with a slit-like delivery port.
[0073] The rinsing liquid nozzle 13 has an elongated shape and is
disposed such that the longitudinal direction of the elongated
shape is horizontal, as in the developing solution nozzle 11. The
rinsing liquid nozzle 13 has a plurality of delivery ports on the
bottom face to deliver the rinsing liquid as a belt as a whole. The
rinsing liquid nozzle 13 is detachably attached to the distal end
of a third nozzle scan arm 18 by a holding member 15b. A third
guide rail 30 is disposed on the bottom plate 4 at a position
outside the second guide rail 25. The third nozzle scan arm 18 is
attached through an X-axis driving mechanism 34 to the upper end of
a third vertical support member 31, which stands up in a vertical
direction from the third guide rail 30. Consequently, the rinsing
liquid nozzle 13 is horizontally movable together with the third
vertical support member 31 in the Y-direction by a Y-axis driving
mechanism 32. The purified water nozzle 12 and the rinsing liquid
nozzle 13 can pass by each other in the Y-direction. Further, the
third vertical support member 31 is movable up and down by a Z-axis
driving mechanism 33, so that the rinsing liquid nozzle 13 can be
moved between a delivery position closer to the wafer W and a
non-delivery position on the upper side by an up-and-down movement
of the third vertical support member 31. Furthermore, the third
nozzle scan arm 18 is movable in the X-direction by the X-axis
driving mechanism 34, so that the rinsing liquid nozzle 13 is also
movable in the X-direction.
[0074] In a first method for supplying the rinsing liquid onto the
wafer W, the rinsing liquid nozzle 13 is placed above the wafer W,
and the rinsing liquid is delivered as a belt from the rinsing
liquid nozzle 13 while the wafer W is rotated. In another method
for supplying the rinsing liquid onto the wafer W, the rinsing
liquid nozzle 13 is moved for scanning in the Y-direction above the
wafer W, while the rinsing liquid is delivered as a belt from the
rinsing liquid nozzle 13. In this second method, the wafer W may be
held stationary or rotated. Further, the scanning by the rinsing
liquid nozzle 13 in the Y-direction may be performed between the
opposite ends of the wafer W in the Y-direction, or between the
center of the wafer W and one end-thereof in the Y-direction. The
rinsing liquid may be continuously supplied such that the rinsing
liquid overflows from the wafer W. Alternatively, the rinsing
liquid may be supplied such that a rinsing liquid puddle is formed
on the wafer W and is held in this state for a predetermined
time.
[0075] As shown in FIG. 1, on the right side of the cup CP, a
developing solution nozzle waiting portion 71 is disposed for the
developing solution nozzle 11 to wait. The developing solution
nozzle waiting portion 71 is provided with a cleaning mechanism
(not shown) for cleaning the developing solution nozzle 11. On the
left side of the cup CP, a purified water nozzle waiting portion 72
and a rinsing liquid nozzle waiting portion 73 are disposed for the
purified water nozzle 12 and rinsing liquid nozzle 13 to wait,
respectively. The purified water nozzle waiting portion 72 and
rinsing liquid nozzle waiting portion 73 are provided with cleaning
mechanisms (not shown) for cleaning the purified water nozzle 12
and rinsing liquid nozzle 13, respectively.
[0076] FIG. 3 is a view schematically showing the structure of a
liquid supply system used in the developing apparatus (DEV). The
developing solution nozzle 11 is connected to a developing solution
supply line 42 for supplying the developing solution from a
developing solution tank 41 that stores the developing solution.
The developing solution supply line 42 is provided with a pump 43
for supplying the developing solution and an ON/OFF valve 44.
[0077] The purified water nozzle 12 is connected to a purified
water supply line 47 for supplying purified water from a purified
water tank 46 that stores purified water. The purified water supply
line 47 is provided with a pump 48 for supplying purified water and
an ON/OFF valve 49.
[0078] The rinsing liquid nozzle 13 is connected to a purified
water supply line 52 for supplying purified water from the purified
water tank 46. The purified., water supply line 52 is provided with
a mixing valve 54 on the way. The mixing valve 54 is connected to a
surfactant solution supply line 56 extending from a surfactant
solution tank 55 that stores a surfactant solution. The surfactant
solution is mixed with purified water within the mixing valve 54.
Consequently, the rinsing liquid nozzle 13 can deliver the
surfactant-containing rinsing liquid prepared by mixing the
surfactant solution with purified water. The purified water supply
line 52 and surfactant solution supply line 56 are respectively
provided with pumps 53 and 57 upstream from the mixing valve 54.
Further, the purified water supply line 52 is provided with an
ON/OFF-valve 58-downstream from the mixing valve 54.
[0079] As described above, the surfactant solution is diluted by
means of inline processing because the necessary amount of
surfactant varies depending on process conditions and/or patterns.
Accordingly, this arrangement makes it possible to use a
high-concentration surfactant solution, while suitably diluting it
with purified water, so as to match it with any requirement.
[0080] Various operation devices used in the developing apparatus
(DEV), such as the Y-axis driving mechanisms 23, 27, and 32, the
Z-axis driving mechanisms 24, 28, and 33, the X-axis driving
mechanisms 29 and 34, the drive motor 3, the pumps 43, 48, 53, and
57, the ON/OFF valves 44, 49, and 58, and the mixing valve 54, are
controlled by a control section 80 for controlling sequential
processes performed on the wafer W in the developing apparatus
(DEV).
[0081] The control section (i.e., a computer) 80 for controlling
processes performed on the wafer W is connected to a data I/O
section 81 including, e.g., a keyboard and a display. The keyboard
is used for a process operator to input commands for determining
process conditions and so forth for the wafer W. The display is
used for showing calculation results obtained by the control
section 80 and visualized images of the operational status of
cleaning processes and so forth. Further, the control section 80 is
connected to a storage section 82 that stores programs and recipes
for controlling the developing apparatus (DEV), data concerning
processes already performed, and so forth.
[0082] More specifically, as described later, the storage section
82 stores programs for the control section 80 to execute various
kinds of control over, e.g., the rotation number of the wafer W,
operation of the various nozzles, and supply/stop of the developing
solution, in the developing apparatus (DEV), so as to perform a
series of processes, such as developing process, rinsing process,
and drying process, on the wafer W. Further, the storage section 82
stores recipes concerning the time allocation of a series of
processes performed on the wafer W, and the flow rate and time for
supply of the developing solution and so forth in the processes.
The process programs and recipes are stored in a fixed storage
medium, such as a hard disk (HD) or memory (RAM or the like), or a
portable storage medium selected from various types, such as a
CD-ROM (or CD-R or the like), DVD-ROM (or DVD-R or the like), or MO
disk, and are readable by the control section 80.
[0083] Furthermore, the storage section 82 stores performance data
concerning process performed in the developing apparatus (DEV),
such as the lot number of wafers W, process recipes used, the date
and time of processes, and the presence/absence of malfunction of
various driving mechanisms in processes. The performance data can
be copied or transferred into a portable storage medium selected
from various types, such as a CD-R or MO disk.
[0084] Next, a detailed explanation will be given of the rinsing
liquid delivered from the rinsing liquid nozzle 13 (specifically,
the rinsing liquid is a surfactant solution itself where a
surfactant solution stored in the surfactant solution tank 55 is
used as the rinsing liquid as it is; or the rinsing liquid is a
diluted solution prepared by mixing where a surfactant solution is
mixed with purified water at a predetermined ratio).
[0085] Polyethylene glycol sorbitan fatty acid esters (one type of
polyethylene glycol family surfactants) respectively having
different hydrophobic groups were used as different five
surfactants A to E. FIG. 4 is a graph showing the relationship
between surfactant concentrations and surface tension where the
surfactants A to E were respectively dissolved into purified water.
FIG. 5 is a graph showing CD fluctuations where aqueous solutions
respectively containing the surfactants A to E in predetermined
concentrations were used for performing a rinsing process after a
developing process. FIG. 6 is a graph showing the number of
precipitation defects, such as particles, where aqueous solutions
respectively containing the surfactants A to E in predetermined
concentrations were used for performing a rinsing process after a
developing process. Further, Table 1 shows data of the surfactants
A to E in terms of the structures of the hydrophobic groups, the
molecular weights, the HLB (hydrophile-lipophile balance) value,
and the presence/absence of double bonds.
TABLE-US-00001 TABLE 1 Hydrophobic Molecular Double Surfactants
group weight bond HLB A n-C.sub.11H.sub.23 1228 absence 16.7 B
n-C.sub.15H.sub.31 1284 absence 15.6 C n-C.sub.17H.sub.35 1312
absence 14.9 D n-C.sub.17H.sub.33 1310 presence 15 E
n-C.sub.39H.sub.73 1839 presence 11
[0086] The general formula of the polyethylene glycol sorbitan
fatty acid ester is expressed by the following composition formula
1. In the composition formula 1, R1 denotes a hydrophobic
group.
##STR00001##
[0087] As shown in Table 1, the surfactants A to E had HLB values
of 10 or more. This is so because, if the HLB value is less than
10, emulsification (i.e., micelle generation) is easily caused due
to the surfactant, and micelles may remain on the wafer W and
generate particles.
[0088] As shown in FIG. 4, with an increase in the concentration of
the surfactants A to E, the surface tension of the aqueous solution
first decreases and then becomes constant. Further, where the
concentration exceeds a certain concentration, surfactant molecules
are agglomerated and generate micelles when the surfactant is
dissolved into purified water. When generation of micelles starts,
the surface tension of the aqueous solution becomes constant.
Accordingly, in other words, the critical micelle concentration
(which will be referred to as "CMC") can be found from a change in
the surface tension of the aqueous solution. As shown in FIG. 4,
the surfactants A to E have CMC values within a range of about 50
to 100 ppm.
[0089] As shown in FIG. 5, the CD fluctuation is lowest in the
aqueous solutions having a low surfactant concentration of 50 ppm
(lower than CMC), and are highest in the aqueous solutions having a
high surfactant concentration of 300 ppm (higher than CMC).
Further, as shown in FIG. 6, for all of the surfactants A to E,
where the aqueous solutions have a surfactant concentration of 50
ppm, the number of precipitation defects is far smaller than that
of purified water used as the rinsing liquid. However, at 100 ppm
or more for the surfactant A and at 300 ppm for the surfactants B
to D, the number of precipitation defects measured is higher than
that of purified water used as the rinsing liquid. It is thought
that this resulted from micelles generated in the aqueous solution.
Further, the number of precipitation defects differs among the
surfactants A to E even at the same concentration of 300 ppm. It is
thought that this related to a fact that the surfactants differed
in aptness in generating micelles at this concentration.
[0090] From the results shown in FIGS. 5 and 6, it has been found
that the surfactant concentration in the rinsing liquid should be
set to be CMC or less, in order to suppress the CD fluctuation and
to suppress generation of precipitation defects. On the other hand,
where the surfactant concentration in the rinsing liquid is too
low, the decrease in the surface tension of the aqueous solution
becomes insufficient. In this case, pattern fall may be caused when
the rinsing liquid supplied on the wafer W is thrown off from the
wafer W. Further, the effect of suppressing the CD fluctuation and
generation of precipitation defects becomes insufficient.
Accordingly, also in light of the effect of preventing pattern
fall, the surfactant concentration in the rinsing liquid is
preferably set at a value near CMC and that does not bring about
generation of micelles in the aqueous solution. Of the surfactants
A to E, the surfactant E is most preferable, and the concentration
thereof is preferably set to be 50 ppm.
[0091] FIG. 7 is a graph showing the relationship between
surfactant molecular weights and CD fluctuations where aqueous
solutions respectively containing the surfactants A to C in a
concentration of 100 ppm were used for performing a rinsing process
after a developing process. Further, FIG. 8 is a graph showing the
relationship between surfactant molecular weights and the number of
precipitation defects where aqueous solutions respectively
containing the surfactants A to C in a concentration of 100 ppm
were used for performing a rinsing process after a developing
process. As shown in FIGS. 7 and 8, it has been found that, with an
increase in the surfactant molecular weight, the CD fluctuation is
suppressed, and the number of precipitation defects becomes
smaller.
[0092] Judging from the results described above, the surfactant
molecular weight is preferably set to be larger within a range with
which the surfactant can be dissolved in purified water. Of them,
the surfactant molecular weight is preferably set at a value, such
as 1,280 or more, that can suppress-the number of precipitation
defects to be lower than about 3,500 obtained by purified water
used for the rinsing process and shown in FIG. 6. Further, since
the hydrophilic group portions of the surfactants A to E have
essentially the same molecular weight, it is thought with reference
to Table 1 that the carbon number of the hydrophobic group is
preferably larger than 11 and more preferably 14 or more. The
polymerization degree of the hydrophilic group portions is
distributed, and thus the difference in the molecular weight of the
surfactants A to E does not completely agree with the difference in
the molecular weight of the hydrophobic groups.
[0093] FIG. 9 is a graph showing CD fluctuations where aqueous
solutions respectively containing the surfactants C and D in a
concentration of 100 ppm were used for performing a rinsing process
after a developing process. Further, FIG. 10 is a graph showing the
number of precipitation defects where aqueous solutions
respectively containing the surfactants C and D in a concentration
of 100 ppm were used for performing a rinsing process after a
developing process. As shown in FIGS. 9 and 10, the surfactant C
suppresses the CD fluctuation and decreases the number of
precipitation defects, as compared to the surfactant D.
[0094] The difference between the surfactant C and surfactant D
resides in the presence/absence of double bonds in hydrophobic
groups. Accordingly, it is thought that the result shown in FIGS. 9
and 10 was caused because double bonds in hydrophobic groups
dissolved resist patterns. Judging from the results described
above, it has been found that the rinsing liquid preferably
contains a surfactant with hydrophobic groups including only single
bonds and excluding double bonds. Further, the rinsing liquid
preferably contains no surfactant with hydrophobic groups including
triple bonds, because such a surfactant is thought to have a
property similar to a surfactant including double bonds.
[0095] As described above with reference to the results shown in
FIGS. 4 to 6 and 8 to 10, it is possible to suppress the CD
fluctuation and generation of precipitation defects, where the
rinsing liquid contains a surfactant while satisfying one of the
following three conditions. Specifically, the surfactant
concentration is set to be CMC or less; the surfactant molecular
weight is large (preferably 1,280 or more) and the carbon number of
hydrophobic groups is larger than 11 (preferably 14 or more); and
the hydrophobic groups include no double bonds. The rinsing liquid
most preferably satisfies these three conditions at the same
time.
[0096] If surfactant micelles are generated in the surfactant
solution stored in the surfactant solution tank 55, it may be
difficult to completely decompose the micelles so as to dissolve
the surfactant forming the micelles into purified water, when the
surfactant solution is diluted by purified water. Accordingly, the
surfactant solution stored in the surfactant solution tank 55
preferably has a concentration set to be CMC or less.
[0097] A surfactant dissolved in the rinsing liquid is not limited
to polyethylene glycol sorbitan fatty acid ester, and another
polyethylene glycol family surfactant may be used for this purpose.
Specifically, an alternative is polyethylene glycol straight-chain
alkyl ester shown in the following composition formula 2,
polyethylene glycol fatty acid ester shown in the following
composition formula 3, straight-chain alkyl addition type
polyethylene glycol phenyl ester shown in the following composition
formula 4, or branched-chain alkyl addition type polyethylene
glycol phenyl ester shown in the following composition formula 5.
Even in the alternative case, the same effect as in use of
polyethylene glycol sorbitan fatty acid ester can be obtained by
satisfying the conditions described above in relation to, e.g., the
surfactant concentration and the carbon number of hydrophobic
groups. Further, the same holds true for a case where an
alternative is EO addition type acetylene glycol shown in the
following composition formula 6, which is one of acetylene glycol
family surfactants. In the composition formulas 2 to 6, R2 to R5
denote hydrophobic groups.
##STR00002##
[0098] Next, an explanation will be given of a developing process
performed by the developing apparatus (DEV). In this developing
process, a rinsing process is performed by use of a rinsing liquid
containing a surfactant as one of those described above in a
predetermined concentration, as a matter of course.
[0099] FIG. 11 is a flowchart showing a first developing process.
At first, a wafer W is subjected to light exposure with a
predetermined pattern, and is then subjected to a post-exposure
baking process and a subsequent cooling process. Then, the wafer W
is transferred by the transfer arm T of the wafer transfer unit to
a position directly above the cup CP. Then, the wafer W is
transferred by the lifter pins 5 onto the spin chuck 2 and is held
by vacuum suction (STEP 1).
[0100] Then, the developing solution nozzle 11 is moved to a
position above the center of the wafer W. Then, while the
developing solution is delivered as a belt from the developing
solution nozzle 11, the wafer W is rotated by 180.degree. or more,
such as 360.degree.. Consequently, the developing solution is
applied all over the surface of the wafer W to form a developing
solution puddle (STEP 2). Alternatively, the developing solution
nozzle 11 may be moved along the guide rail 21 for scanning while
delivering the developing solution.
[0101] Then, the state of the wafer W with the developing solution
applied thereon is held stationary for a predetermined time, such
as 60 seconds, to promote the development (STEP 3). During this
time, the developing solution nozzle 11 is retreated out of the cup
CP, and the nozzle arm 18 of the rinsing liquid nozzle 13 is moved
to place the rinsing liquid nozzle 13 at a position above the
center of the wafer W (STEP 4).
[0102] When the developing time has elapsed, the wafer W is rotated
to throw off the developing solution from the wafer W (STEP 5).
Then, while the rinsing liquid containing a predetermined amount of
surfactant as one of those described above is delivered as a belt
from the rinsing liquid nozzle 13, the wafer W is rotated at a
predetermined rotation number (such as 500 to 2,000 rpm) to perform
a rinsing process (STEP 6). Before the rinsing liquid is supplied,
the rinsing liquid nozzle 13 is preferably subjected to dummy
dispensing at the waiting position to prevent surfactant residues
or the like deposited in the rinsing liquid nozzle 13 from being
supplied onto the wafer W. This makes it possible to reliably
prevent particle generation due to the rinsing liquid.
[0103] The rinsing liquid nozzle 13 can supply the rinsing liquid
onto the wafer W in a short time with low impact, and thereby
enhance the effect of suppressing the CD fluctuation. This rinsing
process may be performed such that the wafer W is held stationary
or the wafer W is rotated at a predetermined rotation number (such
as 1,000 rpm or less), while the rinsing liquid nozzle 13 is moved
along the guide rail 30 for scanning.
[0104] After the rinsing liquid is supplied for a predetermined
time, the rinsing liquid nozzle 13 is retreated out of the cup CP.
Then, the-rotation number of the wafer W is increased to expand the
rinsing liquid on the wafer W and to throw off the rinsing liquid
from the wafer W to dry the wafer W (STEP 7). This step is
preferably performed such that the wafer W is first rotated at a
rotation number of 300 to 1,000 rpm, such as 500 rpm, for 5 to 15
seconds, such as 10 seconds, and the wafer W is then rotated at a
rotation number of 1,000 to 4000 rpm, such as 2,000 rpm, for 10 to
20 seconds, such as 15 seconds. Where operations are performed to
throw off the rinsing liquid from the wafer W and to spin-dry the
wafer W, as described above, it is possible to effectively prevent
pattern fall from being caused.
[0105] After the wafer W is treated by the drying process, the
wafer W is lifted by the lifter pins 5 above the spin chuck 2, and
is then unloaded by the transfer arm T of the wafer transfer unit
from the developing apparatus (DEV) (STEP 8). Then, the wafer W is
subjected to a post baking process.
[0106] According to the first developing process described above,
the rinsing liquid is prepared to contain a surfactant in a
predetermined concentration and to satisfy predetermined conditions
described above. Consequently, it is possible to suppress
generation of precipitation defects, such as particles; to suppress
the CD fluctuation and dissolution of resist patterns; and to
prevent pattern fall from being caused, without performing a
rinsing process using purified water. It follows that resist
patterns can be formed with high cleanliness and precision.
[0107] Next, an explanation will be given of a second developing
process with reference to the flowchart shown in FIG. 12. A first,
as in the first developing process, a wafer W treated by a light
exposure process is held on the spin chuck 2 by vacuum suction
(STEP 101). Then, the developing solution nozzle 11 is moved to a
position above the center of the wafer W. Then, while the
developing solution is delivered as a belt from the developing
solution nozzle 11, the wafer W is rotated by 180.degree. or more,
such as 360.degree.. Consequently, the developing solution is
applied all over the surface of the wafer W to form a developing
solution puddle (STEP 102).
[0108] Then, the state of the wafer W with the developing solution
applied thereon is held stationary for a suitable time, such as 60
seconds, to promote the development (STEP 103). During this time,
the nozzle arm 14 of the developing solution nozzle 11 is retreated
out of the cup CP, and the purified water nozzle 12 is moved to
place the purified water nozzle 12 at a position above the center
of the wafer W (STEP 104).
[0109] When a predetermined time for promoting the development
reaction has elapsed, the wafer W is rotated by the spin chuck 2 to
throw off the developing solution (STEP 105). Then, a rinsing
process using purified water is performed (STEP 106). In this
rinsing process, the following operation is preferably performed.
Specifically, when the rotation number of the wafer W reaches 500
to 2,000 rpm, such as 1,000 rpm, purified water is supplied for 2
seconds or more, such as 5 seconds, while the rotation number is
maintained. Then, while purified water is supplied, the rotation
number of the wafer W is decreased to 100 to 1,000 rpm, such as 500
rpm, and this rotation number is maintained for 2 seconds or more,
such as 10 seconds. The rotation number of the wafer W in STEP 106
is set at an optimum value selected in accordance with the size of
a wafer W to be processed.
[0110] Incidentally, there may be a case where a hardly soluble
layer, which is thus difficult to remove by ordinary rinsing, is
formed on the resist film on the wafer W, if purified water is
supplied directly after the developing solution is thrown off. In
this respect, where rinsing using purified water and the developing
solution is performed prior to rinsing using only purified water,
it is possible to prevent a hardly soluble layer from being
generated on the resist film.
[0111] After the purified water rinsing is performed, the purified
water nozzle 12 is retreated out of the cup CP, and the nozzle arm
18 of the rinsing liquid nozzle 13 is moved to place the rinsing
liquid nozzle 13 at a position essentially above the center of the
wafer W (STEP 107). Then, while the wafer W is rotated preferably
at 500 rpm or less, such as 100 rpm, the rinsing liquid containing
a surfactant as one of those described above is supplied onto the
wafer W to replace most of the purified water and residual
developing solution on the resist film with the rinsing liquid
(STEP 108). In other words, the surface of the resist film is
replaced with the rinsing liquid. Where the wafer W is rotated at
500 rpm or less while the surfactant-containing rinsing liquid is
supplied, as described above, the amount of rinsing liquid thrown
off by the rotation can be decreased without deteriorating the
replacement ability of the rinsing liquid. Consequently, the
consumption amount of the rinsing liquid can be set as low as
possible.
[0112] After the rinsing liquid is supplied onto the wafer W, the
rotation number of the wafer W is increased to expand the rinsing
liquid and to throw off the rinsing liquid to dry the wafer W (STEP
109). This step is preferably performed such that the wafer W is
first rotated at a rotation number of 300 to 1,000 rpm, such as 500
rpm, for 5 to 15 seconds, such as 10 seconds, and the wafer W is
then rotated at a rotation number of 1,000 to 4000 rpm, such as
2,000 rpm, for 10 to 20 seconds, such as 15 seconds. Where
operations are performed to throw off the rinsing liquid from the
wafer W and to spin-dry the wafer W, as described above, it is
possible to effectively prevent pattern fall from being caused.
[0113] After the wafer W is treated by the drying process, the
wafer W is lifted by the lifter pins 5 above the spin chuck 2, and
is then unloaded by the transfer arm T of the wafer transfer unit
from the developing apparatus (DEV) (STEP 110). Then, the wafer W
is subjected to a post baking process.
[0114] Also in the second developing process described above, the
rinsing liquid is prepared to contain a surfactant in a
predetermined concentration and to satisfy predetermined conditions
described above. Consequently, it is possible to suppress
generation of precipitation defects, such as particles, and to
suppress the CD fluctuation and dissolution of resist patterns,
without performing a rinsing process using purified water. Further,
after the rinsing liquid containing a surfactant in a predetermined
concentration is supplied onto the wafer W, an operation is
performed to throw off the rinsing liquid to dry the wafer W. This
makes it possible to prevent pattern fall from being caused.
[0115] FIGS. 13A to 13F are views schematically showing the process
flows of the first to sixth developing processes. In FIGS. 13A to
13F, a reference symbol 111 represents a developing process, a
reference symbol 112 represents a rinsing process using a
surfactant-containing rinsing liquid, a reference symbol 113
represents a drying process, and a reference symbol 114 represents
a rinsing process using purified water. The first process shown in
FIG. 13A and the second process shown in FIG. 13B have already been
explained above, and thus their explanation will be omitted.
Accordingly, an explanation will be given of the processes shown in
FIGS. 13C to 13F.
[0116] The third developing process comprises a developing process
using a developing solution, a rinsing process using a
surfactant-containing rinsing liquid, a rinsing process using
purified water, and a drying process, performed in this order. The
fourth developing process comprises a developing process using a
developing solution, a rinsing process using purified water, a
rinsing process using a surfactant-containing rinsing liquid, a
rinsing process using purified water, and a drying process,
performed in this order. The fifth developing process comprises a
developing process using a developing solution, a rinsing process
using a surfactant-containing rinsing liquid, a developing process
using a developing solution, a rinsing process using purified
water, and a drying process, performed in this order. The sixth
developing process comprises a rinsing process using a
surfactant-containing rinsing liquid, a drying process,
a-developing process using a developing solution, a rinsing process
using purified water; and a drying process, performed in this
order. These processes also make it possible to suppress generation
of precipitation defects and to suppress the CD fluctuation and
dissolution of resist patterns.
[0117] Each of the third developing process shown in FIG. 13C, the
fifth developing process shown in FIG. 13E, and the sixth
developing process shown in FIG. 13F is a process including a final
stage arranged to supply purified water onto the surface of the
wafer W, and then throw off this purified water from the wafer W to
dry the wafer W. Accordingly, these processes are suitable for a
case where no problem arises due to pattern fall caused by the
surface tension of purified water.
[0118] The present invention is not limited to the embodiments
described above, and it may be modified in various manners. For
example, in the embodiments described above, the water-based
cleaning liquid is exemplified by purified water, but the liquid
may be prepared by adding a small amount of another substance into
purified water. Further, the rinsing liquid nozzle 13 is
exemplified by a structure configured to deliver the rinsing liquid
as a belt. Alternatively, the rinsing liquid nozzle 13 may be a
nozzle of the straight type, as in the purified water nozzle 12. In
this case, the rinsing liquid nozzle 13 preferably has a structure
that can set the impact onto a wafer W as low as possible while
maintaining the necessary flow rate of the rinsing liquid.
[0119] Further, in the embodiments described above, the present
invention is applied to a developing process performed on a
semiconductor wafer, but this is not limiting. For example, the
present invention may be applied to a developing process performed
on another substrate, such as a substrate for liquid crystal
display devices (LCD), as long as a miniaturized resist pattern can
be formed on the substrate. Furthermore, the present invention
includes various modifications made by suitably combining some of
the components of the embodiments described above or removing a
part of the components, as long as they do not depart from the
scope of the present invention.
[0120] The embodiments described above are intended only to explain
the technical content of the present invention, and, therefore, the
invention should not be construed as being limited to the specific
details of the embodiments. Various modifications may be made
without departing from the spirit of the present invention or scope
defined by the appended claims.
[0121] The present invention is suitably applied to a process and
apparatus for manufacturing semiconductor devices or flat panel
displays.
* * * * *