U.S. patent application number 11/174500 was filed with the patent office on 2005-12-08 for film forming apparatus and film forming method.
This patent application is currently assigned to Tokyo Electron Limited. Invention is credited to Ishida, Hiroshi.
Application Number | 20050268849 11/174500 |
Document ID | / |
Family ID | 19093530 |
Filed Date | 2005-12-08 |
United States Patent
Application |
20050268849 |
Kind Code |
A1 |
Ishida, Hiroshi |
December 8, 2005 |
Film forming apparatus and film forming method
Abstract
An apparatus for forming a film on a wafer comprising, a first
coating apparatus coating a foaming insulation film material on the
wafer, a second coating apparatus coating a non-porous insulation
film material on the wafer, a low oxygen heating temperature
regulating process apparatus performing a heating process on the
wafer on which the foaming insulation film material is coated, a
low oxygen high temperature heating process apparatus performing
the heating process on the water on which the non-foaming
insulation film material is coated, a transfer mechanism
transferring the wafer to these apparatuses, and a selecting means
selecting a path to which the wafer is transferred corresponding to
the film formed on the wafer.
Inventors: |
Ishida, Hiroshi; (Tokyo-To,
JP) |
Correspondence
Address: |
RADER FISHMAN & GRAUER PLLC
LION BUILDING
1233 20TH STREET N.W., SUITE 501
WASHINGTON
DC
20036
US
|
Assignee: |
Tokyo Electron Limited
Tokyo-To
JP
|
Family ID: |
19093530 |
Appl. No.: |
11/174500 |
Filed: |
July 6, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11174500 |
Jul 6, 2005 |
|
|
|
10231193 |
Aug 30, 2002 |
|
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Current U.S.
Class: |
118/719 |
Current CPC
Class: |
H01L 21/67178 20130101;
H01L 21/67225 20130101; H01L 21/67207 20130101; H01L 21/6715
20130101 |
Class at
Publication: |
118/719 |
International
Class: |
C23C 016/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 4, 2001 |
JP |
2001-267395 |
Claims
1. An apparatus for forming a film on a substrate, comprising: a
first coating apparatus coating a foaming material on the
substrate; a second coating apparatus coating an insulation
material on the substrate; a first heating apparatus heating the
substrate on which the foaming material is coated so as to form a
porous insulation film thereon; a second heating apparatus heating
the substrate on which the insulation material is coated so as to
form a non-porous insulation film thereon; transferring means for
transferring the substrate into at least one of the first coating
apparatus, the second coating apparatus, the first heating
apparatus and the second heating apparatus; and selecting means for
selecting one of the first coating apparatus and the second coating
apparatus, one of the first heating apparatus and the second
heating apparatus to which the substrate is transferred to
corresponding to the film formed on the substrate.
2. The apparatus as set forth in claim 1, wherein at least one of
the first coating apparatus and the second coating apparatus
performs coating with a spin coat process.
3. The film forming apparatus as set forth in claim 1, wherein the
selecting means selects a path to which the substrate is
transferred to so that layers of insulation films are formed on the
substrate in the order of the porous film made of the foaming
material, the non-porous film made of the insulation material and
the porous film made of the foaming material.
4. The apparatus as set forth in claim 1, wherein the selecting
means selects the path to which the substrate is transferred to so
that the substrate is transferred in the order of the first coating
apparatus, the first heating apparatus, the second coating
apparatus, the second heating apparatus, the first coating
apparatus and the first heating apparatus.
5. The film forming apparatus as set forth in claim 1, wherein the
selecting means selects the path to which the substrate is
transferred to so that the substrate is transferred in the order of
the first coating apparatus, the second heating apparatus, the
first heating apparatus, the second coating apparatus, the second
heating apparatus, the first coating apparatus, the second heating
apparatus and the first heating apparatus.
6. The apparatus as set forth in claim 1, wherein the first heating
apparatus comprises: a plate on which the substrate is placed; and
cooling means for cooling the plate.
7. (canceled)
8. The method as set forth in claim 7, wherein step (d) is further
followed by the steps in the order of step (a) and step (b) the
9. (canceled)
10. (canceled)
11. (canceled)
12. An apparatus for forming a film on a substrate, comprising: a
first coating apparatus coating a porous insulation film material
on the substrate with a spin coat process; a first heating
apparatus heating the substrate on which the porous insulation
material is coated so as to form a first insulation film thereon; a
second coating apparatus coating a non-porous insulation film
material on the substrate with the spin coat process; a second
heating apparatus heating the substrate on which the non-porous
insulation material is coated so as to form a second insulation
film thereon; and a transferring mechanism transferring the
substrate among the first coating apparatus, the second coating
apparatus, the first heating apparatus and the second heating
apparatus.
13. The apparatus as set forth in claim 12, further comprising: a
reforming apparatus reforming a front surface of the first
insulation film, wherein the transferring mechanism transfers the
substrate to the reforming apparatus.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a film forming apparatus
that forms a porous insulation film and a non-porous insulation
film on a substrate such as a semiconductor wafer.
[0003] 2. Description of the Related Art
[0004] An insulation film is formed on a substrate in such a manner
that an insulation film material is coated on the substrate, dried,
and heated. A system that integrally performs a series of
processing steps such as a coating process, a drying process, and a
heating process for an insulation film material is known.
[0005] Recently, the improvement of the insulating characteristic
of an insulation film has been required. In order to meet the
requirement, a porous insulation film has been used. For such a
coating material, a material such that contains porogen in an
insulation film material like methyl silsesquioxane (hereinafter
abbreviated as MSQ) is used. In addition, after the coating process
for such a material is performed, a heating process is performed
under a different condition (for example, at different temperature)
from the conventional heating process for a non-porous insulation
film.
[0006] In the dual damascene method, which has been widely used in
recent years, to improve the etching accuracy or to form a hard
mask and the like, two or more types of insulation films are
laminated. Thus, usually, both of the non-porous insulation film
and the porous insulation film are formed on one semiconductor
wafer. Since the condition for forming the porous insulation film
is different from the condition for forming the non-porous
insulation film, a separate system from a system for forming the
non-porous insulation film has been provided for forming the porous
insulation film. Thus, the facility becomes large. In addition, a
wafer has to be transferred between the systems and, as a result,
the process is not effectively performed taking a long time to
complete.
[0007] In general, after the porous insulation film is formed, in a
case of laminating another insulation film such as the non-porous
insulation film thereon, the insulation film is formed with CVD
(Chemical Vapor Deposition) method. By the CVD method, a very thin
film is formed in comparison with a film formed with a method of
rotating the substrate, namely spin coating method. Since the front
surface of a porous insulation film as a lower layer is largely
rugged, an insulation film as an upper layer laminated by the CVD
method is also largely rugged. As a result, a flat film cannot be
formed.
SUMMARY OF THE INVENTION
[0008] The present invention is made from the above-described point
of view. An object of the present invention is to provide a film
forming apparatus and a film forming method that allow the
installation space of the facility to be reduced and a laminate
film made of a porous insulation film and a non-porous insulation
film to be effectively formed.
[0009] Another object of the present invention is to provide a film
forming apparatus and a film forming method that allow an upper
insulation film to be flatly formed on a porous insulation
film.
[0010] To solve the problem, a film forming apparatus of the
present invention comprises a first coating apparatus coating a
foaming material on the substrate, a second coating apparatus
coating an insulation material on the substrate, a first heating
apparatus heating the substrate on which the foaming material is
coated so that a porous insulation film is formed thereon, a second
heating apparatus heating the substrate on which the insulation
material is coated so that a non-porous insulation film is formed
thereon, transferring means for transferring the substrate into at
least one of the first coating apparatus, the second coating
apparatus, the first heating apparatus and the second heating
apparatus and selecting means for selecting one of the first
coating apparatus and the second coating apparatus, one of the
first heating apparatus and the second heating apparatus to which
the substrate is transferred to corresponding to the film formed on
the substrate.
[0011] According to the present invention, with providing the
selecting means that selects processing apparatuses to which the
wafer W is transferred corresponding to a type of film formed on
the substrate, film forming processes for a porous insulation film
and a non-porous insulation film can be performed in the same
system. Thus, unlike the conventional system, it is not necessary
to transfer the substrate between different systems. As a result,
film forming processes can be effectively performed. Thus, the
installation space of the apparatus can be reduced. As a result,
the time taken for processing can be shortened.
[0012] Another aspect of the film forming apparatus of the present
invention comprises a first coating apparatus coating a porous
insulation film material on the substrate with a spin coat process,
a first heating apparatus heating the substrate on which the porous
insulation material is coated so as to form a first insulation film
thereon, a second coating apparatus coating a non-porous insulation
film material on the substrate with the spin coat process, a second
heating apparatus heating the substrate on which the non-porous
insulation material is coated so as to form a second insulation
film thereon and a transferring mechanism transferring the
substrate among the first coating apparatus, the second coating
apparatus, the first heating apparatus and the second heating
apparatus.
[0013] According to the present invention, the first coating
apparatus coats a porous insulation material with the spin coat
process and the second coating apparatus coats a non-porous
insulation material with the spin coat process. Thus, even if the
front surface of the porous insulation film is largely rugged
(namely, the surface roughness thereof is large), the non-porous
insulation film as an upper layer can be flatly formed. In
addition, since all the processes including the heating process of
the first heating apparatus and the second heating apparatus are
performed in the same apparatus that has a transferring mechanism,
unlike the conventional art, it is not necessary to transfer a
substrate between different systems. As a result, the film forming
processes can be effectively performed. Thus, the installation
space of the apparatus can be reduced. As a result, the time taken
for processing can be shortened.
[0014] A film forming method of the present invention comprising
the steps of, (a) coating a porous insulation material on a
substrate with a spin coat process, (b) heating the substrate on
which the porous insulation film material is coated so as to form a
first insulation film thereon, (c) coating a non-porous insulation
material on the substrate on which the first insulation film is
formed with the spin coat process. (d) heating the substrate on
which the non-porous insulation material is coated so as to form a
second insulation film thereon.
[0015] According to the present invention, a porous insulation
material is coated with the spin coat process. In addition, a
non-porous insulation material is coated with the spin coat process
in the second coating apparatus. Thus, even if the front surface of
the porous insulation film is largely rugged (namely, the surface
roughness thereof is large), the non-porous insulation film as an
upper layer can be flatly formed.
[0016] Another embodiment of the present invention performs the
steps in the order of step (a) and step (b) after performing step
(d). In such a manner, since a porous insulation film as a third
layer is formed with the spin coat process, the film can be
effectively formed in, for example, the same apparatus.
[0017] Another example of the present invention further comprising
the step (e) of reforming a front surface of the first insulation
film, the step (e) being performed between the steps (b) and (c).
In this example, the reforming process is performed by radiating an
ultraviolet ray to the first insulation film. With such reforming
process, the water absorption of the front surface of the film is
improved and the film becomes hydrophilic. As a result, the contact
angle of the non-porous insulation film material to the porous
insulation film becomes small, therefore, the non-porous material
can be easily coated. In other words, when a non-porous insulation
material is spread on a substrate by the spin coat process, the
material can easily be spread and flattened. In addition, since the
material can easily be spread, the amount required of the material
can be reduced.
[0018] Another embodiment of the present invention comprises the
step of coating a solvent on the first insulation film with the
spin coat process, after the reforming process. Thus, water
absorption of the front surface of the porous film can be improved
further. When a non-porous insulation material is spread on a
substrate by the spin coat process, the material can easily be
spread and flattened. In addition, since the material can easily be
spread, the amount required of the material can be reduced.
[0019] These and other objects, features and advantages of the
present invention will become more apparent in light of the
following detailed description of a best mode embodiment thereof,
as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a plan view of a film forming apparatus according
to an embodiment of the present invention.
[0021] FIG. 2 is a side view of the film forming apparatus shown in
FIG. 1.
[0022] FIG. 3 is a side view showing the other side of the film
forming apparatus shown in FIG. 1.
[0023] FIG. 4 is a perspective view showing a transfer mechanism of
the film forming apparatus shown in FIG. 1.
[0024] FIGS. 5A, 5B, 5C, and 5D are schematic diagrams showing
semiconductor device fabrication processes according to an
embodiment of the present invention.
[0025] FIG. 6 is a flow chart showing the semiconductor device
fabrication processes according to the embodiment of the present
invention.
[0026] FIG. 7 is a flow chart showing semiconductor device
fabrication processes according to another embodiment of the
present invention.
[0027] FIG. 8 is a sectional view showing a coating apparatus
(SCT).
[0028] FIG. 9 is a plan view showing the coating apparatus
(SCT).
[0029] FIG. 10 is a front sectional view showing a low oxygen
heating temperature regulating process apparatus (MHC).
[0030] FIG. 11 is a front sectional view showing a low oxygen high
temperature heating process apparatus (DLB)
[0031] FIG. 12 is a partial plan view showing the low oxygen
heating temperature regulating process apparatus (MHC) and the low
oxygen high temperature heating process apparatus (DLB).
[0032] FIG. 13 is a side view showing a film forming apparatus
according to another embodiment of the present invention.
[0033] FIGS. 14A, 14B, 14C, 14D, 14E, 14F, 14G, and 14H are
schematic diagrams for explaining semiconductor device fabrication
processes with dual damascene method.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0034] Next, with reference to the accompanying drawings, an
embodiment of the present invention will be described.
[0035] In the embodiment, a fabrication method for a semiconductor
device having a laminated film composed of three layers of
insulation films in FIG. 5D will be described.
[0036] As shown in FIG. 5D, a lower layer wiring 201 is formed on a
semiconductor wafer W (hereinafter abbreviated as wafer W). On the
lower layer wiring 201, an inter-layer insulation film composed of
layers of laminated films is formed. The inter-layer insulation
film is composed of a porous insulation film 202, a non-porous
insulation film 203, and a porous insulation film 204. A porous
insulation film is a film made with processing a foaming material.
In the inter-layer insulation film, for example through-holes (not
shown) are formed. Via the through-holes, a wiring (not shown) that
is made of a conductive material and formed on the inter-layer
insulation film and the lower layer wiring 201 are connected.
[0037] As the porous insulation films 202 and 204, for example a
porous MSQ material can be used. On the other hand, as the
non-porous insulation film 203, an organic material such as PAE
(poly arylene ether) can be used.
[0038] When a porous insulation film is used as the inter-layer
insulation film, a high insulating characteristic can be achieved.
For example, in the foregoing structure, a capacitance formed
between the lower layer wiring 201 and the wiring formed on the
inter-layer insulation film can be reduced.
[0039] FIGS. 1 to 4 are external views showing a film forming
apparatus used to form the foregoing insulation films of the
semiconductor device. FIG. 1 is a plan view showing the film
forming apparatus. FIGS. 2 and 3 are side views showing the film
forming apparatus.
[0040] The film forming apparatus is designated by reference
numeral 1. The film forming apparatus 1 is composed of a cassette
station 2, a processing station 3, an aligner 4, and an interface
portion 5 that are integrally connected. The cassette station 2 is
used to transfer a cassette C that contains for example 25 wafers W
from the outside to the film forming apparatus 1. In addition, the
cassette station 2 loads and unloads wafers with a cassette C. The
processing station 3 has various types of processing apparatuses
that are stacked in multiple stages. The aligner 4 is disposed
adjacent to the processing station 3. The interface portion 5 is
used to transfer a wafer W between the processing station 3 and the
aligner 4.
[0041] In the cassette station 2, a plurality of cassettes C can be
aligned at positions of assignment protrusions 10a on a cassette
holding table 10 in an X direction (in the upper and lower
direction of FIG. 1) in such a manner that wafer access portions of
the cassettes C face the processing station 3. A wafer transfer
mechanism 11 can travel in the direction of which the cassettes C
are aligned (X direction) and the direction of which wafers W are
contained in each cassette C (Z direction: vertical direction). The
wafer transfer mechanism 11 can travel along a transferring path
12. Thus, the wafer transfer mechanism 11 can selectively access
each cassette C.
[0042] Moreover, the wafer transfer mechanism 11 can rotate in a
.theta. direction shown in FIG. 1. Thus, the wafer transfer
mechanism 11 can access an extension unit (EXT) 74 and an extension
unit (EXT) 93. The extension unit (EXT) 74 transfers the wafer W
between a wafer transfer mechanism 11 of a multi-staged unit
portion of a first processing apparatus group 70 and a first
transfer mechanism 50 that will be described later. The extension
unit (EXT) 93 transfers the wafer W between a wafer transfer
mechanism 11 of a fourth processing apparatus group 90 and a second
transfer mechanism 60 that will be described later.
[0043] In addition, a controller 120 is disposed on the cassette
holding table 10 The controller 120 has a selecting means 120a for
selecting a processing apparatus to which the first transfer
mechanism 50 that will be described later transfers the wafer W
corresponding to a film formed on the wafer W conveyed to the film
forming apparatus 1. For example, information on to which path the
transfer mechanism 50 should follow when transferring the wafer W
to one of the above-mentioned apparatuses is pre-input to the
selecting means 120a.
[0044] On the front side of the processing station 3, a first
coating apparatus group 20 composed of a material coating
apparatus, a resist coating apparatus, and an exchange coating
apparatus are disposed. On the rear side of the processing station
3, a second coating apparatus group 30 composed of developing
process apparatuses is disposed.
[0045] As shown in FIGS. 2 and 3, in the first coating apparatus
group 20, a resist coating apparatuses 22 and 24 are stacked. In
the first coating apparatus group 20, a foaming insulation film
material coating apparatus 23 as a first coating apparatus and a
non-foaming insulation film material coating apparatus 21 as a
second coating apparatus are also stacked. The resist coating
apparatus 24 places a wafer W on a spin chuck in a cup CP and coats
a resist solution on the wafer W with spin coat process. In such a
manner, the resist coating apparatus 24 performs a resist coating
process for the wafer W. The foaming insulation film material
coating apparatus 23 places a wafer W on a spin chuck in a cup CP
and coats a foaming insulation film material as a foaming material
with the spin coat process. In this example, a porous MSQ material
is coated. In such a manner, the foaming insulation film material
coating apparatus 23 performs the foaming insulation film material
coating process for the wafer W. The non-foaming insulation film
material coating apparatus 21 places a wafer W on a spin chunk in a
cup CP and coats a non-foaming insulation film material as an
insulation material with the spin coat process. In this example, an
organic material such as PAE is coated. In such a manner, the
non-foaming insulation film material coating apparatus 21 performs
the non-foaming insulation film coating process for the wafer
W.
[0046] As shown in FIGS. 2 and 3, in the second coating apparatus
group 30, developing process apparatuses 33 and 31 and developing
process apparatuses 34 and 32 are stacked. Each of the developing
process apparatuses 31 to 34 places a wafer W on a spin chuck in a
cup CP, supplies a developing solution, and performs a developing
process for the wafer W.
[0047] At a center portion of the processing station 3, a
transferring table 40 on which a wafer W can be placed is
disposed.
[0048] The first coating apparatus group 20 and the second coating
apparatus group 30 are oppositely disposed with the transferring
table 40. The first transfer mechanism 50 as a transferring means
is disposed between the first coating apparatus group 20 and the
transferring table 40. The second transfer mechanism 60 is disposed
between the second coating apparatus group 30 and the transferring
table 40.
[0049] The structure of the first transfer mechanism 50 is
basically the same as the structure of the second transfer
mechanism 60. For simplicity, only the structure of the first
transfer mechanism 50 will be described with reference to FIG. 4.
The first transfer mechanism 50 is composed of a cylindrical
supporting member 53 and a wafer transferring means 54. The
cylindrical supporting member 53 is composed of a pair of wall
portions 51 and 52 that are oppositely disposed and connected at
the top and bottom. The wafer transferring means 54 is disposed in
the cylindrical supporting member 53. The wafer transferring means
54 can lift up and down in an upper and lower direction (Z
direction). The cylindrical supporting member 53 is connected to a
rotating shaft of a motor 55. A rotating and driving force of the
motor 55 causes the cylindrical supporting member 53 to rotate
together with the wafer transferring means 54 around the rotating
shaft of the motor 55. Thus, the wafer transferring means 54 can
rotate freely in the .theta. direction.
[0050] On a transfer base 56 of the wafer transferring means 54, a
plurality of pairs of tweezers are disposed as holding members that
hold the wafer W. For example, two pairs of tweezers 57 and 58 are
disposed as a pair of upper tweezers and a pair of lower tweezers.
The structure of the pair of tweezers 57 is basically the same as
the structure of the pair of tweezers 58. The pairs of tweezers 57
and 58 have a shape and a size that allow them to freely enter the
side opening portions of the wall portions 51 and 52 of the
cylindrical supporting member 53. The pairs of tweezers 57 and 58
can travel in a forward and backward direction by a motor (not
shown) disposed in the transfer base 56. Likewise, the second
transfer mechanism 60 has two pairs of tweezers 67 and 68 each pair
of which has the same function and structure as each pair of the
tweezers 57 and 58.
[0051] A first processing apparatus group 70 and a second
processing apparatus group 80 are oppositely disposed with the
first transfer mechanism 50 so that the first processing apparatus
group 70 and the second processing apparatus group 80 are disposed
in the vicinity of the first coating apparatus group 20. In the
first processing apparatus group 70, a variety of types of
apparatuses are stacked on multiple stages. The fourth processing
apparatus group 90 and a third processing apparatus group 100 are
oppositely disposed with the second transfer mechanism 60 so that
the fourth processing apparatus group 90 and the third processing
apparatus group 100 are disposed in the vicinity of the second
coating apparatus group 30.
[0052] The first processing apparatus group 70 and the fourth
processing apparatus group 90 are disposed adjacent to the cassette
station 2. The second processing apparatus group 80 and the third
processing apparatus group 100 is disposed adjacent to the
interface portion 5.
[0053] Next, with reference to FIG. 2 that shows the processing
station 3 viewed from the cassette station 2, the structure of the
first processing apparatus group 70 and the fourth processing
apparatus group 90 will be described.
[0054] In the first processing apparatus group 70, a low oxygen
heating temperature regulating process apparatus (MHC) 72 as a
first heating apparatus, a low oxygen high temperature heating
process apparatus (DLB) 75 as a second heating apparatus, an
alignment unit (ALIM) 73, an extension unit (EXT) 74, a low
temperature heating processing apparatus (LHP) 77, and a low oxygen
curing and cooling processing apparatus (DLC) 78 are stacked in
order from the bottom to the top. The alignment unit (ALIM) 73
aligns a wafer W. The extension unit (EXT) 74 causes a wafer W to
wait for the next process.
[0055] In the fourth processing apparatus group 90, an alignment
unit (ALIM) 92, an extension unit (EXT) 93, pre-baking units
(PREBAKE) 94 and 95, and post-baking units (POBAKE) 96, 97, and 98
are stacked in order from the bottom to the top. The pre-baking
units (PREBAKE) 94 and 95 perform a heating process for a wafer W
after a resist has been coated for the wafer W. The post-baking
units (POBAKE) 96, 97, and 98 perform a heating process for a wafer
W after a developing process has been performed for the wafer
W.
[0056] Next, with reference to FIG. 3 that shows the processing
station 3 viewed from the interface portion 5, the structure of the
second processing apparatus group 80 and the third processing
apparatus group 100 will be described.
[0057] In the second processing apparatus group 80, cooling units
(COL) 81 and 82, an alignment unit (ALIM) 83, an extension unit
(EXT) 84, and cooling units (COL) 85, 86, 87, and 88 are stacked in
order from the bottom to the top.
[0058] In the third processing apparatus group 100, pre-baking
units (PREBAKE) 101 and 102, post-exposure baking units (PEB) 103
and 104, and post-baking units (POBAKE) 105, 106, and 107 are
stacked in order from the bottom to the top. The post-exposure
baking units (PEB) 103 and 104 perform a heating process for a
wafer W after an exposing process is performed for the wafer W.
[0059] In the interface portion 5, a wafer transfer mechanism 110
is disposed. The wafer transfer mechanism 110 can access the
extension unit (EXT) 84 of the second processing apparatus group 80
and the post-exposure baking units (PEB) 103 and 104 of the third
processing apparatus group 100.
[0060] The wafer transfer mechanism 110 can travel along a rail 111
in the X direction, lift up and down in the Z direction (the
vertical direction of FIG. 1), and rotate in the .theta. direction.
The wafer transfer mechanism 110 can transfer a wafer W to the
aligner 4 and a peripheral aligner 112.
[0061] The foaming insulation film material coating apparatus 23 as
the first coating apparatus and the non-foaming insulation film
material coating apparatus 21 as the second coating apparatus
perform a coating process by the spin coat process and almost have
the same structure.
[0062] FIGS. 8 and 9 are a sectional view and a plan view showing
these coating apparatuses (SCT), respectively. A ring-shaped cup CP
is disposed at a center portion of the coating apparatus (SCT). The
cup CP has a drainage pipe 153. A spin chuck 152 is disposed inside
the cup CP. While the spin chuck 152 is holding a semiconductor
wafer W by the vacuum absorption method, the spin chuck 152 is
rotated and driven by a drive motor 154. The drive motor 154 is
disposed so that it can lift up and down at an opening 151a of a
unit bottom plate 151. The drive motor 154 is connected to a
lifting driving means 160 and a lifting guiding means 162 through a
cap-shaped flange member 158 made of aluminum. The lifting driving
means 160 is composed of for example an air cylinder.
[0063] A supply pipe 183 is connected from an insulation film
material supply source (not shown) to the nozzle 177. The nozzle
177 is detachably disposed at an edge portion of a nozzle scan arm
176 through a nozzle holding member 172. The nozzle scan arm 176 is
disposed at an upper edge portion of a vertical holding member 175.
The vertical holding member 175 can horizontally travel on a guide
rail 174 disposed in one direction (Y direction) of the unit bottom
plate 151. The nozzle scan arm 176 moves together with the vertical
holding member 175 in the Y direction in a Y direction by a driving
mechanism (not shown).
[0064] Next, the low oxygen heating temperature regulating process
apparatus (MHC) 72 as the first heating apparatus and the low
oxygen high temperature heating process apparatus (DLB) 75 as the
second heating apparatus will be described.
[0065] FIG. 10 is a front sectional view showing the low oxygen
heating temperature regulating process apparatus (MHC) as the first
heating apparatus. FIG. 12 is a partial plan view showing the low
oxygen heating temperature regulating process apparatus (MHC). The
low oxygen heating temperature regulating process apparatus (MHC)
is an apparatus that performs a heating process for a foaming
insulation film material coated on a wafer W.
[0066] In a processing chamber 251 of the low oxygen heating
temperature regulating process apparatus (MHC), a plate 252 and an
arm 223 are disposed. The plate 252 is used to perform a heating
process for a wafer W at for example 200 to 800.degree. C. The arm
223 transfers the wafer W between the first transfer mechanism 50
and the plate 252. The arm 223 receives the wafer W from the pair
of tweezers 57 of the first transfer mechanism 50 and transfers the
wafer W to the plate 252. The arm 223 has a cooling mechanism. The
wafer W heated on the plate 252 is cooled on the arm 223.
Thereafter, the wafer W is transferred to the pair of tweezers 57
of the first transfer mechanism 50. The plate 252 is made of the
same material as the wafer W. When a wafer W is made of silicon,
the plate 252 is also made of silicon. As a result, when a heating
process is performed for the wafer W, a heat reflection between the
wafer W and the plate 252 can be suppressed. Thus, in the heating
process that will be described later, the temperature of the wafer
W can be accurately measured. The volume of the plate 252 is almost
equal to the volume of the wafer W. Thus, the heat capacity applied
to the plate 252 can accurately be calculated for controlling the
temperature. Alternatively, the volume of the plate 252 may be
different from the volume of the wafer W. For example, the volume
of the plate 252 may be a multiple of the volume of the wafer W. As
long as the temperature of the plate 252 can easily be controlled,
the volume thereof can be changed. According to the embodiment, the
plate 252 is designed so that its thickness is lower than the
thickness of a plate disposed in the low oxygen high temperature
heating process apparatus (DLB) as the second heating apparatus
that will be described later. Thus, in comparison with the plate of
the low oxygen high temperature heating process apparatus (DLB),
the heat capacity of the plate 252 can be decreased. As a result,
the temperature of the plate 252 can be controlled in a short time.
Thus, the temperature of the heating process for a wafer W can be
easily varied corresponding to the material of a film formed
thereon. In other words, when a coated foaming insulation film
material is heated and a porous insulation film is formed, there
are many opportunities of which the temperature condition is
changed. Thus, in such a structure, the processes can be
effectively performed.
[0067] The plate 252 is peripherally divided into three areas R1 to
R3. For each of the divided three areas R1 to R3, the temperature
control is performed. In other words, heaters H1 to H3 are
concentrically buried in the areas R1 to R3 of the plate 252,
respectively. In addition, temperature detecting devices D1 to D3
are buried in the areas R1 to R3 of the plate 252, respectively. In
addition, a cooling pipe 253 that cools the plate 252 is disposed
on the rear surface of the plate 252. In the cooling pipe 253, a
liquid for example demineralized water that has been cooled at for
example 15.degree. C. to 23.degree. C. is circulated through a
freezer (not shown). With such a cooling means, the temperature of
the plate 252 can quickly be lowered. In addition to the heaters H1
to H3, the temperature control for the plate 252 can accurately and
quickly be performed. With a plurality of heaters, for example
three, the plate 252 is area-controlled. In contrast, with the
cooling pipe 253 as a cooling means, the plate 252 is not
area-controlled. As a result, while the temperature control is
accurately accomplished, the structure is simplified. Of course,
with the cooling means, the cooling pipe 253 can also be
area-controlled. As the heating means, an infrared ray or the like
can be used instead of heaters. As the cooling means, a Peltier
device or the like can be used.
[0068] At a lower portion of the processing chamber 251, a N.sub.2
supply opening 255 is disposed. The N.sub.2 supply opening 255
discharges N.sub.2 gas supplied from an N.sub.2 source 254 to the
processing chamber 251. A pipe 256 is connected between the N.sub.2
source 254 and the N.sub.2 supply opening 255. A valve 257 is
disposed on the pipe 256. The valve 257 adjusts the discharge
amount of the N.sub.2 supply opening 255. Alternatively, a means
for heating and cooling N.sub.2 gas may be disposed on the pipe 256
so as to adaptively control the temperature of the N.sub.2 gas.
[0069] In addition, at an upper portion of the processing chamber
251, an exhaust opening 258 is disposed. The exhaust opening 258
deaerates the processing chamber 251 by the vacuum exhaust method.
A vacuum pump 260 is connected to the exhaust opening 258 through a
pipe 259.
[0070] A controlling portion 261 estimates the temperature of the
heating process for the wafer W corresponding to the detected
results of the temperature detecting devices D1 to D3.
Corresponding to the estimated temperature, the controlling portion
261 controls powers supplied to the heaters H1 to H3 so that the
temperatures of the areas R1 to R3 become predetermined
temperatures. When necessary, the controlling portion 261 also
controls the temperature and amount of the liquid supplied to the
cooling pipe 253. When necessary, the controlling portion 261
controls the discharging amount of the N.sub.2 gas and the degree
of vacuum of the chamber.
[0071] A plurality of holes 262, for example three, concentrically
pierce the plate 252. Support pins 263 that support a wafer W are
inserted into the holes 262 so that the support pins 263 can lift
up and down in the holes 262. The support pins 263 are integrally
connected to a connecting member 264 disposed on the rear surface
of the plate 252. The connecting member 264 is lifted up and down
with a lifting cylinder 265 disposed below the connecting member
264. The lifting cylinder 265 causes the support pins 263 to
protrude and recess from the front surface of the plate 252.
[0072] An opening portion 266 is disposed on the front surface of
the processing chamber 251. Through the opening portion 266, a
wafer W is transferred with the first transfer mechanism 50. The
opening portion 266 can be closed with a shutter member 267. When
the opening portion 266 is closed with the shutter member 267, the
interior of the processing chamber 251 can be air-tightly closed
and effectively deaerated.
[0073] A wall portion 268 that composes the processing chamber 251
and that surrounds an area R including the plate 252 has a
temperature regulating mechanism 269 that adjusts the temperature
of the area R. The temperature regulating mechanism 269 is composed
of a heater 270 and a cooling pipe 271 that are buried in the wall
portion 268. The controlling portion 261 controls the power
supplied to the heater 270 and the temperature and amount of
cooling water supplied to the cooling pipe 271. The temperature
regulating mechanism 269 allows the temperature of the processing
chamber 251 to be accurately controlled.
[0074] When the wall portion 268 is vertically divided into for
example three areas R4 to R6 and they are separately controlled by
the temperature regulating mechanism 269, not only the temperature,
but the air flow in the processing chamber 251 can be controlled.
For example, when the temperatures of the areas of the processing
chamber 251 are controlled so that the temperature of the upper
area becomes higher than the temperature of the lower area, an
upward air flow is intentionally generated. As a result, a
sublimate or the like that is produced from the wafer W can be
securely exhausted to the outside (through for example the exhaust
opening 258) without adversely affecting the wafer W. According to
the embodiment, the wall portion of the outer periphery of the
processing chamber 251 is controlled. Of course, the upper and
lower wall portions can be controlled.
[0075] FIG. 11 is a front sectional view showing the low oxygen
high temperature heating process apparatus (DLB) as the second
heating apparatus. FIG. 12 is a partial plan view showing the low
oxygen high temperature heating process apparatus (DLB). The low
oxygen high temperature heating process apparatus (DLB) is
different from the forgoing low oxygen heating temperature
regulating process apparatus (MHC) except that the former does not
have the cooling mechanism of the plate 252 and the arm 223. The
low oxygen high temperature heating process apparatus (DLB) is an
apparatus that performs a heating process for a non-foaming
insulation film material or a foaming insulation film material that
is coated on a wafer W.
[0076] In a processing chamber 351 of the low oxygen high
temperature heating process apparatus (DLB), a plate 352 used to
perform a heating process for a wafer W at for example 200 to
800.degree. C. is disposed. The plate 352 is made of the same
material as a wafer W. When a wafer W is made of silicon, the plate
352 is also made of silicon. As a result, when a heating process is
performed for a wafer W, a heat reflection between the wafer W and
the plate 352 can be suppressed. Thus, in the heating process that
will be described later, the temperature of the wafer W can be
accurately estimated. The volume of the plate 352 is almost equal
to the volume of the wafer W. Thus, the heat capacity applied to
the plate 352 can be accurately calculated for controlling the
temperature. However, the volume of the plate 352 may be different
from the volume of the wafer W. For example, the volume of the
plate 352 may be a multiple of the volume of the wafer W. Of
course, as long as the temperature of the plate 352 can easily be
controlled, the volume thereof can be changed.
[0077] The plate 352 is peripherally divided into three areas R1 to
R3. For each of the divided three areas R1 to R3, the temperature
control is performed. In other words, heaters H1 to H3 are
concentrically buried in the areas R1 to R3 of the plate 352,
respectively. In addition, temperature detecting devices D1 to D3
are buried in the areas R1 to R3 of the plate 352, respectively. As
the heating means, an infrared ray or the like can be used instead
of heaters.
[0078] At a lower portion of the processing chamber 351, a N.sub.2
supply opening 355 is disposed. The N.sub.2 supply opening 355
discharges N.sub.2 gas supplied from an N.sub.2 source 354 into the
processing chamber 351. A pipe 356 is connected between the N.sub.2
source 354 and the N.sub.2 supply opening 355. A valve 357 is
disposed on the pipe 356. The valve 357 adjusts the discharge
amount of the N.sub.2 supply opening 355. Alternatively, a means
for heating and cooling N.sub.2 gas may be disposed on the pipe 356
so as to adaptively control the temperature of the N.sub.2 gas.
[0079] In addition, at an upper portion of the processing chamber
351, an exhaust opening 358 is disposed. The exhaust opening 258
deaerates the processing chamber 351 by the vacuum exhaust method.
A vacuum pump 358 is connected to the exhaust opening 359 through a
pipe 360.
[0080] A controlling portion 361 estimates the temperature of the
heating process for the wafer W corresponding to the detected
results of the temperature detecting devices D1 to D3.
Corresponding to the estimated temperature, the controlling portion
361 controls powers supplied to the heaters H1 to H3 so that the
temperatures of the areas R1 to R3 become predetermined
temperatures. When necessary, the controlling portion 361 controls
the discharging amount of the N.sub.2 gas and the degree of vacuum
of the chamber.
[0081] A plurality of holes 362, for example three, concentrically
pierces the plate 352. Support pins 362 that support a wafer W are
inserted into the holes 363 so that the support pins 263 can lift
up and down through the holes 262. The support pins 363 are
integrally connected to a connecting member 364 disposed on the
rear surface of the plate 352. The connecting member 364 is lifted
up and down with a lifting cylinder 365 disposed below the
connecting member 264. The lifting cylinder 365 causes the support
pins 363 to protrude and recess from the front surface of the plate
352.
[0082] An opening portion 366 is disposed on the front surface of
the processing chamber 351. Through the opening portion 366, a
wafer W is transferred with the first transfer mechanism 50. The
opening portion 367 can be closed with a shutter member 367. When
the opening portion 367 is closed with the shutter member 367, the
interior of the processing chamber 351 can be air-tightly closed
and effectively deaerated.
[0083] A wall portion 368 that composes the processing chamber 351
and that surrounds an area R including the plate 352 has a
temperature regulating mechanism 369 that adjusts the temperature
of the area R. The temperature regulating mechanism 369 is composed
of a heater 370 and a cooling pipe 371 that are buried in the wall
portion 368. The controlling portion 361 controls the power
supplied to the heater 370 and the temperature and amount of
cooling water supplied to the cooling pipe 371. The temperature
regulating mechanism 369 allows the temperature of the processing
chamber 351 to be accurately controlled. When the wall portion 368
is vertically divided into for example three areas R4 to R6 and
they are separately controlled by the temperature regulating
mechanism 369, not only the temperature, but the air flow in the
processing chamber 351 can be controlled. For example, when the
temperatures of the areas of the processing chamber 251 are
controlled so that the temperature of the upper area becomes higher
than the temperature of the lower area, an upward air flow is
intentionally generated. As a result, a sublimate or the like that
is produced from the wafer W can be securely exhausted to the
outside (through for example the exhaust opening 358) without
adversely affecting the wafer W. According to the embodiment, the
wall portion of the outer periphery of the processing chamber 351
is controlled. Of course, the upper and lower wall portions can be
controlled.
[0084] Next, with reference to FIGS. 5A, 5B, 5C, 5D, and 6, a
fabrication method for an insulation film composed of a laminate of
a semiconductor device using the foregoing film forming apparatus
will be described. FIGS. 5A to 5D are schematic diagrams explaining
fabrication processes for a semiconductor device. FIG. 6 is a flow
chart showing fabrication processes for an insulation film of a
laminate film using the foregoing film forming apparatus.
[0085] As shown in FIG. 5A, a wafer W on which a lower layer wiring
201 has been formed is prepared. The wafer W is placed in a
cassette C on the cassette holding table 10. Thereafter, the
operator inputs information of a film to be formed on the wafer W
to the controller 120. According to the embodiment, information of
an insulation film composed of three layers of a porous insulation
film, a non-porous insulation film, and a porous insulation film to
be formed on the wafer W is input to the controller 120.
Corresponding to the input information, the controller 120
determines apparatuses to which the first transfer mechanism 50
transfers the wafer W and in what order. The first transfer
mechanism 50 operates corresponding to the result. According to the
embodiment, when a porous insulation film is formed, the controller
120 selects the foaming insulation film material coating apparatus
(SCT) 23 as a coating apparatus and the low oxygen heating
temperature regulating process apparatus (MHC) 72 as a heating
apparatus as major apparatuses to which the wafer W is transferred.
When a non-porous insulation film is formed, the controller 120
selects the non-foaming insulation film material coating apparatus
(SCT) 21 as a coating apparatus and the low oxygen high temperature
heating process apparatus (DLB) 75 as a heating apparatus as major
apparatuses to which the wafer W is transferred. After the
information is input, the wafer W that has not been processed is
transferred from the wafer cassette CR placed on the cassette
holding table 10 to the extension unit (EXT) 74 of the first
processing apparatus group 70 that is adjacent to the processing
station 3 through the wafer transfer mechanism 11.
[0086] The wafer W transferred to the transferring table of the
extension unit (EXT) 74 is transferred to for example a cooling
unit (COL) 81 of the second processing apparatus group 80 through
the first transfer mechanism 50. The cooling unit (COL) 81 cools
the wafer W to for example around 23.degree. C. (at step S1).
[0087] The wafer W for which the cooling process has been performed
by the cooling unit (COL) 81 is transferred to the foaming
insulation film material coating apparatus (SCT) 23 of the first
coating apparatus group 20 through the first transfer mechanism 50.
The foaming insulation film material coating apparatus 23 coats a
foaming material of for example around 500 nm on the wafer W with
the spin coat process (at step S2). As a result, a foaming
insulation material coating film is formed on the lower layer
wiring 201 of the wafer W. In this example, as the foaming
insulation film material, a porous MSQ material is used.
[0088] The wafer W on which the foaming insulation film material
has been coated by the foaming insulation film material coating
apparatus (SCT) 23 is transferred to the low temperature heating
processing unit (LHP) 77 of the first processing apparatus group
through the first transfer mechanism 50. The low temperature
heating processing apparatus (LHP) 77 performs a low temperature
heating process for the wafer W for 60 seconds at for example
around 100.degree. C. (at step S3).
[0089] The wafer W for which the low temperature heating process
has been performed by the low temperature heating processing
apparatus (LHP) 77 is transferred to the low oxygen heating
temperature regulating process apparatus (MHC) 72 through the first
transfer mechanism 50. The low oxygen heating temperature
regulating process apparatus (MHC) 72 performs a high temperature
hating process for the wafer W for 30 minutes at around 400.degree.
C. in an oxygen atmosphere of for example 1000 ppm or less so as to
harden and reform the film quality of the foaming insulation film
material coating film (at step S4). As a result, as shown in FIG.
5B, a porous insulation film 202 made of the porous MSQ material is
formed on the lower layer wiring 201 of the wafer W. The heat
quantity required for forming a porous insulation film is larger
than the heat quantity required for forming a non-porous insulation
film.
[0090] Thereafter, the wafer W processed by the low oxygen heating
temperature regulating process apparatus (MHC) 72 is transferred to
for example a cooling unit (COL) 82 of the second processing
apparatus group through the first transfer mechanism 50. The
cooling unit (CPL) 82 cools the wafer W to at around 23.degree. C.
(at step S5).
[0091] The wafer W for which the cooling process has been performed
by the cooling unit (COL) 82 is transferred to the non-foaming
insulation film material coating apparatus (SCT) 21 of the first
coating apparatus group 20 through the first transfer mechanism 50.
The non-foaming insulation film material coating apparatus (SCT) 21
coats a non-foaming insulation film material of for example around
200 nm on the wafer W (at step S6). As a result, a non-foaming
insulation film material coated film is formed on the porous
insulation film 202. In this example, as the non-foaming insulation
film material, PAE material is used.
[0092] The wafer W on which the non-foaming insulation film
material has been coated by the non-foaming insulation film
material coating apparatus (SCT) 21 is transferred to the low
oxygen high temperature heating process apparatus (DLB) 75 through
the first transfer mechanism 50. The low oxygen high temperature
heating process apparatus (DLB) 75 performs a high temperature
heating process for the wafer W for around 60 seconds or less at
for example around 300.degree. C. in a low oxygen atmosphere (at
step S7).
[0093] The wafer W for which the high temperature heating process
has been performed by the low oxygen high temperature heating
process apparatus (DLB) 75 is transferred to the low oxygen curing
and cooling processing apparatus (DLC) 78 through the first
transfer mechanism 50. The low oxygen curing and cooling processing
apparatus (DLC) 78 performs a high temperature heating process for
the wafer W for around five minutes at for example around
450.degree. C. in a low temperature atmosphere so as to harden and
reform the quantity of the non-foaming insulation material coated
film. Thereafter, the low oxygen curing and cooling processing
apparatus (DLC) 78 performs a cooling process for the wafer W at
around 23.degree. C. (at step S8). As a result, as shown in FIG.
5C, a porous insulation film 203 is formed on the porous insulation
film 202.
[0094] The wafer W processed by the low oxygen curing and cooling
processing apparatus (DLC) 78 is transferred to for example the
cooling unit (COL) 85 of the second processing apparatus group 80
through the first transfer mechanism 50. The cooling unit (COL) 85
cools the wafer W to for example around 23.degree. C. (at step
S9).
[0095] The wafer W for which the cooling process has been performed
by the cooling unit (COL) 85 is transferred to the foaming
insulation film material coating apparatus (SCT) 23 of the first
coating apparatus group 20 through the first transfer mechanism 50.
The foaming insulation film material coating apparatus (SCT) 23
coats a foaming insulation film material of for example around 500
nm on the wafer W by the spin coat process (at step S10). A foaming
insulation film material coated film is formed on the lower layer
wiring 201 of the wafer W. In this example, as the foaming
insulation film material, a porous MSQ material is used.
[0096] The wafer W on which the foaming insulation film material
has been coated by the foaming insulation film material coating
apparatus (SCT) 23 is transferred to the low temperature heating
processing apparatus (LHP) 77 of the first processing apparatus
group through the first transfer mechanism 50. The low temperature
heating processing apparatus (LHP) 77 performs a low temperature
heating process for the wafer W for around 60 seconds at for
example 100.degree. C. (at step S11).
[0097] The wafer W for which the low temperature heating process
has been performed by the low temperature heating processing
apparatus (LHP) 77 is transferred to the low oxygen heating
temperature regulating process apparatus (MHC) 72 through the first
transfer mechanism 50. The low oxygen heating temperature
regulating process apparatus (MHC) 72 performs a high temperature
heating process for the wafer W for around 30 minutes at around
400.degree. C. in an oxygen atmosphere of for example 1000 ppm or
below (at step S12). As a result, as shown in FIG. 5D, a porous
insulation film 204 made of an MSQ structure or organic/inorganic
(silica) structure is formed on the non-porous insulation film 203.
As a result, a laminate film of which the porous insulation film
202, the non-porous insulation film 203, and the porous insulation
film 204 that are layered in order can be accomplished.
[0098] In addition, so that after the porous insulation film 202
and/or the non-porous insulation film 203 is formed, the film
quality thereof is reformed and the adhesion of the front surface
of the insulation film is improved, an ultraviolet ray may be
radiated onto the insulation film by an ultraviolet ray radiation
unit (UV) 106 as shown in FIG. 13. By the reforming process, not
only the adhesion, but the water absorption of the front surface of
the film is improved. As a result, the film has a hydrophilic
property. Thus, the contact angle of the non-porous insulation film
material to the porous insulation film becomes small. As a result,
the non-porous material can be easily coated. In other words, when
the porous insulation material is spread on the wafer by the spin
coat process, the porous insulation material can easily be spread
and flattened. In addition, since the material can easily be
spread, the required amount of the material can be reduced.
[0099] In addition, after a ultraviolet ray is radiated, a solvent
such as thinner may be equally coated on the insulation film with
the spin coat process. Thus, not only the non-porous insulation
material can easily be spread on the porous insulation film, but
the required amount of the material can be reduced.
[0100] In addition, according to the forgoing embodiment, the low
oxygen heating temperature regulating process apparatus (MHC) 72 is
disposed so as to harden and reform the film quality of a foaming
insulation film material. In addition, the low oxygen curing and
cooling processing apparatus (DLC) 78 is disposed so as to harden
and reform the film quality of a non-foaming insulation film
material. Alternatively, when an electron radiation curing
processing apparatus (EB) 108 as shown in FIG. 13 is disposed, the
film quality of each film can be hardened and refined. As a result,
the first coating apparatus group 20 and the second coating
apparatus group 30 can be prevented from being adversely affected
by heat.
[0101] In addition, according to the forgoing embodiment, as shown
in FIG. 6, a foaming material is coated (at step S2 or S10) and a
low temperature heating process is performed (at step S3 or S11).
However, depending on a chemical (for example, porous HSQ material)
used as a foaming material, an aging process (at step S2-2 or
S10-2) and a reforming process (at step S2-3 or S10-3) (processed
by a processing apparatus at a position designated by reference
numeral 25 of FIG. 13) may be performed between the formed material
coating process and the low temperature heating process. Likewise,
depending on a chemical used as a non-foaming material, an aging
process (at step S6-2) and a reforming process (at step S6-3) may
be performed between the non-foaming material coating process and
the low oxygen high temperature heating process. The aging process
is performed by aging processing apparatuses (DAC) 76 and 79.
[0102] In the aging processing apparatuses (DAC) 76 and 79, a
mixture of ammonia gas and steam is supplied to a processing
chamber that can be air-tightly closed. In the processing chamber,
an aging process is performed for a wafer W. As a result, an
insulation film material formed on the wafer W is wet-gelled. In
addition, the reforming processing apparatus 25 performs a
reforming process for the wafer W. The reforming processing
apparatus 25 supplies a chemical or gas (for example, MHDS) for the
reforming process to the wafer W. As a result, another molecule is
structure-bonded to a molecular bonded edge portion of the
insulation film coated on the wafer W. As a result, an insulation
film formed on the wafer W can be reformed.
[0103] After the low oxygen heating temperature adjusting process
(at step S12) is completed, the wafer W (not shown) is transferred
to the resist coating apparatus (SCT) 24 of the first coating
apparatus group 20 through the first transfer mechanism 50. The
resist coating apparatus 24 forms a resist film on the wafer W. The
resist film is for example an acetal resist.
[0104] Thereafter, while the wafer W on which the resist film has
been formed is being held by the upper pair of tweezers 57 of the
first transfer mechanism 50, the wafer W is transferred to the
transferring table 40. The wafer W transferred to the transferring
table 40 is held with the pair of tweezers 68 of the second
transfer mechanism 60. Thereafter, the wafer W is transferred to
for example the pre-baking unit (PREBAKE) 101 of the third
processing apparatus group 100. The pre-baking unit (PREBAKE) 101
performs a predetermined heating process for the wafer W. After the
heating process for the wafer W has been performed, while the wafer
W is being held by the pair of tweezers 68 of the second transfer
mechanism 60, the wafer W is transferred to the cooling unit (COL)
86 of the second processing apparatus group 80. The cooling unit
(COL) 86 performs a cooling process for the wafer W. After the
cooling unit (COL) 86 has performed the cooling process for the
wafer W, the wafer W is transferred to the extension unit (EXT) 84
of the second processing apparatus group 80. The extension unit
(EXT) 84 keeps the wafer W awaited.
[0105] Thereafter, the wafer W is transferred from the extension
unit (EXT) 84 to the peripheral aligner 112 with the wafer transfer
mechanism 110. The peripheral aligner 112 removes an unnecessary
resist film from the periphery of the wafer W. Thereafter, the
wafer W is transferred to the aligner 4. The aligner 4 performs a
predetermined exposing process for the wafer W. After a pattern on
the wafer W is exposed by the aligner 4, the wafer W is transferred
to for example the post-exposure baking unit (PEB) 103 of the
second heating processing apparatus group 100 by the wafer transfer
mechanism 110. The post-exposure baking unit (PEB) 103 performs a
heating process for the wafer W.
[0106] Thereafter, the wafer W is held by the pair of tweezers 68
of the second transfer mechanism 60. The wafer W is transferred to
for example the cooling unit (COL) 87 of the second processing
apparatus group 80. The cooling unit (COL) 87 performs a cooling
process for the wafer W. After the cooling unit (COL) 87 performed
the cooling process for the wafer W, it is held by the pair of
tweezers 58 of the first transfer mechanism 50. The wafer W is
transferred to the transferring table 40. Thereafter, while the
wafer W is being held by the pair of tweezers 68, the wafer W is
transferred from the transferring table 40 to for example the
developing process unit (DEV) 31 of the second coating apparatus
group. The developing process apparatus 31 performs a predetermined
developing process for the wafer W. As a result, a predetermined
resist pattern is formed on the wafer W.
[0107] After the developing process for the wafer W is performed,
while the wafer W is being held by the pair of tweezers 67 of the
second transfer mechanism 60, the wafer W is transferred to for
example the post-baking unit (POBAKE) 105 of the third processing
apparatus group 100. The post-baking unit (POBAKE) 105 performs a
heating process for the wafer W for which the developing process is
performed. After the heating process for the wafer W has been
performed by the post-baking unit (POBAKE) 105, while the wafer W
is being held by the pair of tweezers 67 of the second transfer
mechanism 60, the wafer W is transferred to the transferring table
40.
[0108] After the wafer W is transferred to the transferring table
40, while the wafer W is being held by the pair of tweezers 58 of
the first transfer mechanism 50, the wafer W is transferred to for
example the cooling unit (COL) 88 of the second processing
apparatus group 80. The cooling unit (COL) 88 actively performs a
cooling process for the wafer W to a predetermined temperature
[0109] After the cooling process for the wafer W is performed, the
wafer W is transferred to for example the extension unit (EXT) 74
of the first processing apparatus group 70 through the first
transfer mechanism 50. The extension unit (EXT) 74 keeps the wafer
W awaited. Thereafter, the wafer W is transferred from the
extension unit (EXT) 74 by the wafer transfer mechanism 11. The
wafer transfer mechanism 11 places the wafer W in a cassette C on
the cassette holding table 10.
[0110] Thereafter, an etching unit (not shown) performs a dry
etching process for the wafer W with a mask of a resist pattern so
as to form through-holes in the insulation film composed of three
layers. After the editing process for the wafer W has been
performed, the resist pattern is peeled from the wafer W.
[0111] After the etching process and the resist pattern peeling
process for the wafer W is performed, a conduction film is formed
on the insulation film including the surface of the through-holes.
As a result, a semiconductor device of which the conductive file
and the lower layer wiring are connected via through-holes is
accomplished.
[0112] According to the foregoing embodiment, when a porous
insulation film is formed on a wafer W, after a heating process is
performed for the wafer W by the low temperature hating processing
apparatus (LHP), a heating process is performed for the wafer W by
the low oxygen heating temperature regulating process apparatus
(MHC). However, according to another embodiment, at steps S4 and
S13 of FIG. 7, a process of the low oxygen high temperature heating
process apparatus (DLB) can be performed between the process of the
low temperature hating processing apparatus (LHP) and the process
of the low oxygen heating temperature regulating process apparatus
(MHC). In this case, when a porous insulation film is formed on a
wafer W, the controller selects the foaming insulation film
material coating apparatus (SCT) as a coating apparatus and the low
oxygen high temperature heating process apparatus (DLB) and the low
oxygen heating temperature regulating process apparatus (MHC) as
heating apparatuses as major apparatuses to which the wafer W is
transferred. When a non-porous insulation film is formed on a wafer
W, the controller selects the non-foaming insulation film material
coating apparatus (SCT) as a coating apparatus and the low oxygen
high temperature heating process apparatus (DLB) as a heating
apparatus as major apparatuses to which the wafer W is transferred.
In this case, an ideal porous film is formed with the low oxygen
high temperature heating process apparatus (DLB). The porous film
can be dual-bounded by the low oxygen heating temperature
regulating process apparatus (MHC).
[0113] Thus, in the film forming apparatus according to the
embodiment, since the controller that selects processing
apparatuses to which a wafer W is transferred corresponding to a
film to be formed on the wafer W, when a laminate film composed of
a porous insulation film and a non-porous insulation film is
formed, it is not necessary to transfer the wafer W between
different systems unlike the prior art. Thus, according to the
present invention, a film forming process can be effectively
performed.
[0114] Next, the case that the present invention is applied to the
dual damascene method will be described.
[0115] In the same manner as shown in FIGS. 5A, 5B, 5C, and 5D, a
lower layer wiring 201, a porous insulation film 202, a non-porous
insulation film 203, and a porous insulation film 204 are
successively formed as shown in FIGS. 14A, 14B, 14C, and 14D. Next,
as shown in FIGS. 14E, 14F, 14G, and 14H, a wiring groove 205 and a
contract hole 206 are formed with the etching method. As shown in
FIG. 14G, a barrier metal layer 207 is formed with the plating
method. Thereafter, as shown in FIG. 14H, for example a copper 208
is buried and the CMP (Chemical Mechanical Polishing) process is
performed therefore so that both a wiring and a connector are
formed at a time. In FIGS. 14E to 14H, although an etching unit, a
PVD unit, and so forth are used, in the film forming apparatus
according to the present invention, a photolithography process is
performed for the etching process.
[0116] According to the embodiment, in FIGS. 14B to 14D, the porous
insulation films 202 and 204 are coated by the foaming insulation
film material coating apparatus (SCT) 23. The non-porous insulation
film 203 is coated by the non-foaming insulation film material
coating apparatus (SCT) 21. Generally, the front surface of a
porous insulation film is largely rugged in comparison with the
surface flatness of a non-porous insulation film. In other words,
the surface roughness of a porous insulation film is larger than
the surface roughness of a non-porous insulation film. However,
according to the embodiment, since the non-porous insulation film
203 as an upper layer is formed on the porous insulation film 202
as a lower layer by the spin coat process, even if the surface
roughness of the porous insulation film 202 is large, the
non-porous insulation film 203 can be equally formed so that the
surface thereof becomes flat.
[0117] Since a porous film cannot be formed with the conventional
CVD method at present, the porous insulation film 202 should be
formed with the spin coat process. According to the present
invention, in consideration of such a situation, both a porous
insulation film and a non-porous insulation film are formed with
the spin coat process. As a result, it is not necessary to transfer
a wafer W between different systems unlike the prior art. Thus, the
film forming process can be effectively performed. As a result, the
installation space of the apparatus can be reduced. In addition, as
was described above, the non-porous insulation film 203 can be
equally formed so that the front surface thereof becomes flat.
[0118] In addition, according to the embodiment, as the porous
insulation film 202, an organic insulation film can be used. As the
non-porous insulation film 203 and the porous insulation film 204,
inorganic films can be used. Alternatively, as the porous
insulation film 202 and the non-porous insulation film 203, organic
films can be used. As the porous insulation film 204, an organic
film can be used. As an organic film, for example "Porous Silk" of
Dow Chemical Company can be used. As an inorganic film, for example
"LKD Series" of JSR Company or "HSG Series" of Hitachi Chemical
Co., Ltd. can be used.
[0119] Before the etching process shown in FIGS. 14E and 14F is
performed, since a resist film as an organic film is formed on the
porous insulation film 204, it is necessary to use an inorganic
film as the porous insulation film 204.
[0120] In addition, according to the forgoing embodiment, as a
substrate, a semiconductor wafer was exemplified. Alternatively,
the present invention can be applied to a substrate for a liquid
crystal unit.
[0121] According to the present invention, since a selecting means
for selecting processing apparatuses to which a wafer W is
transferred corresponding to a film to be formed on the wafer W is
disposed, film forming processes for a porous insulation film and
an non-porous insulation film can be performed in the same system.
Thus, unlike the prior art, it is not necessary to transfer a wafer
W between different systems. As a result, a film forming process
can be effectively performed. Thus, the installation space for the
apparatus can be reduced.
[0122] In addition, according to the present invention, a flat
insulation film as an upper layer can be formed on a porous
insulation film as a lower layer.
[0123] improving throughput.
[0124] The disclosure of Japanese Patent Application No.
2001-267395 filed Sep. 4, 2001 including specification, drawings
and claims are herein incorporated by reference in its
entirety.
[0125] Although only some exemplary embodiments of this invention
have been described in details as above, those skilled in the art
should readily appreciate that many modifications are possible in
the exemplary embodiments without materially departing from the
novel teachings and advantages of this invention. Accordingly, all
such modifications are intended to be included within the scope of
this invention.
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