U.S. patent application number 11/210883 was filed with the patent office on 2006-01-26 for stage apparatus, exposure apparatus, and semiconductor device manufacturing mehtod.
This patent application is currently assigned to CANON KABUSHIKI KAISHA. Invention is credited to Kazunori Iwamoto, Takashi Meguro, Yasuyo Muto, Yukio Takabayashi.
Application Number | 20060017909 11/210883 |
Document ID | / |
Family ID | 32652550 |
Filed Date | 2006-01-26 |
United States Patent
Application |
20060017909 |
Kind Code |
A1 |
Muto; Yasuyo ; et
al. |
January 26, 2006 |
Stage apparatus, exposure apparatus, and semiconductor device
manufacturing mehtod
Abstract
A stage apparatus has a substrate holding unit which chucks and
holds a substrate, and includes a flat surface having a recess
where the substrate holding unit is to be mounted. A fixing member
fixes a projection support provided to the substrate holding unit
onto the flat surface. The substrate holding unit is supported by
the fixing member while a distal end of the projection support is
in contact with the recess of the flat surface and the remaining
portion of the substrate holding unit is not in contact with the
flat surface.
Inventors: |
Muto; Yasuyo; (Tochigi,
JP) ; Iwamoto; Kazunori; (Tochigi, JP) ;
Takabayashi; Yukio; (Saitama, JP) ; Meguro;
Takashi; (Tochigi, JP) |
Correspondence
Address: |
FITZPATRICK CELLA HARPER & SCINTO
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Assignee: |
CANON KABUSHIKI KAISHA
Tokyo
JP
|
Family ID: |
32652550 |
Appl. No.: |
11/210883 |
Filed: |
August 25, 2005 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10704638 |
Nov 12, 2003 |
6965428 |
|
|
11210883 |
Aug 25, 2005 |
|
|
|
Current U.S.
Class: |
355/72 |
Current CPC
Class: |
H01L 21/68 20130101;
G03F 7/70716 20130101; H01L 21/68792 20130101; Y10T 279/23
20150115; G03F 7/707 20130101; H01L 21/68785 20130101 |
Class at
Publication: |
355/072 |
International
Class: |
G03B 27/58 20060101
G03B027/58 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 13, 2002 |
JP |
2002-329701 |
Claims
1. A stage apparatus having a substrate holding unit which chucks
and holds a substrate, comprising: a flat surface having a recess
where said substrate holding unit is to be mounted; and a fixing
member which fixes a projection support provided to said substrate
holding unit onto the flat surface, wherein said substrate holding
unit is supported by said fixing member while a distal end of said
projection support is in contact with the recess of the flat
surface and a remaining portion of said substrate holding unit is
not in contact with the flat surface.
2-21. (canceled)
Description
[0001] This application is a continuation application of copending
U.S. patent application Ser. No. 10/704,638, filed Nov. 12,
2003.
FIELD OF THE INVENTION
[0002] The present invention relates to a stage apparatus, an
exposure apparatus, and a semiconductor device manufacturing
method.
BACKGROUND OF THE INVENTION
[0003] In recent years, the semiconductor industry has been
changing and progressing very fast. Accordingly, a semiconductor
manufacturing apparatus that can further shrink the feature size
and improve the throughput of elements has been sought. To meet the
demand for a smaller element feature size, the numerical aperture
(NA) of the projection lens has been increased. To manufacture
high-performance elements with high productivity, an increase in
the diameter of the substrate and the like have been performed.
[0004] For example, currently, an exposure system having two stages
has been proposed to improve the throughput and alignment accuracy.
This is an exposure system that transports and transfers a whole
substrate holding unit between two stages as it holds a substrate.
More specifically, according to this exposure system, alignment is
performed at the first stage, and exposure is preformed at the
second stage different from the first stage during alignment. This
makes it possible to ensure high-accuracy alignment time and
improve the throughput.
[0005] To ensure the superiority of this system, first, the
reproducibility of the surface of the substrate holding unit on
different stages must be ensured reliably. More specifically, the
substrate holding unit must be held between the first stage
(alignment stage) and second stage (exposure stage) without
changing the surface state of the substrate holding unit, e.g., the
surface accuracy, distortion, or the like. Furthermore, the
substrate holding unit must be moved between the stages quickly and
must be stationarily held on or removed from a support surface for
the substrate holding unit instantaneously.
[0006] In general, however, when the substrate holding unit and a
support surface for it are to be brought into total contact with
each other, it is difficult to stationarily hold the substrate
holding unit on the support surface or to remove it from the
support surface instantaneously. The substrate holding unit is
highly likely to conform to the shape of the support surface for
it. To reliably, stationarily hold the substrate holding unit,
after it has moved from a stage, on the support surface for it, the
substrate holding unit needs a stationary fixing force that can
withstand stage driving. To ensure reproducibility of the surface
of the substrate holding unit at the second stage different from
the first stage, when the substrate holding unit is to be moved
between the stages or is to be stationarily held on or removed from
the support surface for it, a power that changes the surface of the
substrate holding unit should not be applied to the substrate
holding unit. In a conventional exposure system, however, when the
substrate holding unit is to be moved between the stages or is to
be stationarily held on or removed from the support surface for it
instantaneously, it is difficult to ensure the reproducibility of
the surface of the substrate holding unit on different stages
without changing the surface of the substrate holding unit.
SUMMARY OF THE INVENTION
[0007] The present invention has been made in view of the above
problems, and has as its object to improve the throughput.
[0008] The first aspect of the present invention relates to a stage
apparatus, having a substrate holding unit which chucks and holds a
substrate, comprising a flat surface having a recess where the
substrate holding unit is to be mounted, and a fixing member which
fixes a projection support provided to the substrate holding unit
onto the flat surface, wherein the substrate holding unit is
supported by the fixing member while a distal end of the projection
support is in contact with the recess of the flat surface and a
remaining portion of the substrate holding unit is not in contact
with the flat surface.
[0009] According to a preferred embodiment of the present
invention, the fixing member preferably has a mechanism which
applies no moment force to the projection support.
[0010] According to a preferred embodiment of the present
invention, the recess is preferably a V-shaped groove, and the
projection support preferably comes into point contact with the
V-shaped groove at a distal end thereof.
[0011] According to a preferred embodiment of the present
invention, the projection support preferably comprises at least
three projection supports and the fixing member fixing the
projection supports, respectively.
[0012] According to a preferred embodiment of the present
invention, the projection support and the fixing member preferably
form one component.
[0013] According to a preferred embodiment of the present
invention, the fixing member is preferably fixed to the projection
support.
[0014] According to a preferred embodiment of the present
invention, the fixing member can preferably tilt freely at a
contact portion with the projection support in an axial direction
of the projection support and in a planar direction.
[0015] According to a preferred embodiment of the present
invention, a small gap is preferably present between the projection
support and the fixing member, and the projection support can
preferably tilt freely in an axial direction of the projection
support and in a planar direction because of the gap.
[0016] According to a preferred embodiment of the present
invention, the fixing member preferably has one of a circular
shape, an elliptical shape, a shape similar to an ellipse, or a
polygonal shape.
[0017] According to a preferred embodiment of the present
invention, the fixing member can preferably elastically deform.
[0018] According to a preferred embodiment of the present
invention, the fixing member preferably has an outer seal portion
on an outer surface thereof, and the outer seal portion preferably
comes into contact with the flat surface to define a closed
space.
[0019] According to a preferred embodiment of the present
invention, a seal number is preferably arranged between the
projection support and the fixing member.
[0020] According to a preferred embodiment of the present
invention, the V-shaped groove is preferably formed to extend in
three directions on the flat surface at an angular interval of
about 120.degree..
[0021] According to a preferred embodiment of the present
invention, the stage apparatus preferably has a chucking/holding
mechanism which chucks and holds the projection support onto the
flat surface.
[0022] According to a preferred embodiment of the present
invention, the stage apparatus preferably has a chucking/holding
mechanism which chucks and holds the projection support onto the
substrate holding unit.
[0023] According to a preferred embodiment of the present
invention, the projection support can preferably be removed from
the flat surface by canceling a chucking/holding force from the
chucking/holding mechanism.
[0024] According to a preferred embodiment of the present
invention, the projection support can preferably be removed from
the substrate holding unit by canceling a chucking/holding force
from the chucking/holding mechanism.
[0025] According to a preferred embodiment of the present
invention, the chucking/holding mechanism preferably uses one of a
negative pressure, a Coulomb force, and a magnetic force.
[0026] The second aspect of the present invention relates to a
stage apparatus, having a substrate holding unit which chucks and
holds a substrate, comprising a flat surface having a projection
support where the substrate holding unit is to be mounted, and a
fixing member which fixes the projection support provided to the
flat surface with a recess formed in the substrate holding unit,
wherein the substrate holding unit is supported by the fixing
member while the recess of the substrate holding unit is in contact
with a distal end of the projection support and a remaining portion
of the substrate holding unit is not in contact with the flat
surface.
[0027] The third aspect of the present invention relates to an
exposure apparatus comprising an optical system which projects
exposure light irradiating a master having a pattern onto a
substrate, and a stage apparatus having a substrate holding unit
which holds the substrate or master, wherein the stage apparatus
includes a stage, a flat surface which drives the substrate holding
unit within a predetermined plane, and a fixing member which fixes
a projection support formed on the substrate holding unit onto the
flat surface, and the substrate holding unit is supported while a
distal end of the projection support is in contact with the flat
surface and the substrate holding unit is not in contact with the
flat surface.
[0028] The fourth aspect of the present invention relates to a
semiconductor device manufacturing method comprising an applying
step of applying a photosensitive material on a substrate, an
exposure step of transferring a pattern onto the substrate, applied
with the photosensitive material in the applying step, by utilizing
the exposure apparatus, and a developing step of developing the
photosensitive material on the substrate where the pattern has been
transferred in the exposure step.
[0029] Other features and advantages of the present invention will
be apparent from the following description taken in conjunction
with the accompanying drawings, in which like reference characters
designate the same or similar parts through the figures
thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate embodiments of
the invention and, together with the description, serve to explain
the principles of the invention.
[0031] FIG. 1 is a view showing a stage apparatus according to a
preferred embodiment of the present invention;
[0032] FIG. 2 is an enlarged view of a portion in the vicinity of a
projection support for a wafer chuck;
[0033] FIG. 3 is a view showing the arrangement of V-grooves on a
wafer chuck support surface;
[0034] FIG. 4 is a view of a portion including a fixing member
which ensures a wide surface area where a suction force acts;
[0035] FIG. 5 is a view of a portion in which a fixing member,
which ensures a wide surface area where a suction force acts, is a
different component;
[0036] FIG. 6 is an enlarged view of a portion in the vicinity of a
projection support for a wafer chuck;
[0037] FIG. 7 is an enlarged view of a portion in the vicinity of a
projection support for a wafer chuck;
[0038] FIGS. 8A and 8B are enlarged views of a portion in the
vicinity of a projection support for a wafer chuck;
[0039] FIGS. 9A and 9B are enlarged views of a portion in the
vicinity of a projection support for a wafer chuck;
[0040] FIGS. 10A and 10B are enlarged views of a portion in the
vicinity of a projection support for a wafer chuck;
[0041] FIGS. 11A and 11B are enlarged views of a portion in the
vicinity of a projection support for a wafer chuck;
[0042] FIGS. 12A and 12B are enlarged views of a portion in the
vicinity of a projection support for a wafer chuck;
[0043] FIG. 13 is a conceptual view showing the arrangement of an
exposure apparatus according to a preferred embodiment of the
present invention;
[0044] FIG. 14 is a flow chart showing the flow of an overall
semiconductor device manufacturing process; and
[0045] FIG. 15 is a flow chart showing the detailed flow of the
wafer process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] The preferred embodiments of the present invention will be
described in detail with reference to the accompanying
drawings.
First Embodiment
[0047] A stage apparatus according to the first preferred
embodiment of the present invention will be described in
detail.
[0048] FIG. 1 is a schematic view showing the stage apparatus
according to the preferred embodiment of the present invention.
This stage apparatus has a flat surface 13 for driving a substrate
holding unit (wafer chuck) 9 within a predetermined plane, and a
fixing member 14 for fixing a projection support 11 formed on the
substrate holding unit 9 onto the flat surface 13. The substrate
holding unit 9 is supported while the distal end of the projection
support 11 is in contact with a recess (V-groove) 12 of the flat
surface 13 and the main body of the substrate holding unit 9 is not
in contact with the flat surface (wafer chuck support surface) 13.
With this arrangement, the stage apparatus according the preferred
embodiment of the present invention drives the substrate holding
unit 9 which chucks and holds a substrate.
[0049] The wafer chuck 9 has a pin-shaped projection (not shown)
interspersed on its support surface where a wafer 8 (see FIG. 13)
as a substrate is to be placed. The wafer 8 is placed on the
surfaces of the projections, and is held flat by a negative
pressure or a Coulomb force. The wafer chuck 9 also has the
projection support 11 for supporting the wafer chuck 9 on its
surface opposite to the support surface where the wafer 8 is to be
placed. The wafer chuck support surface 13 for placing the wafer
chuck 9 has the fixing member 14, which supplies a force to only
the projection support 11 with a chucking/holding force. The
projection support 11 and the wafer chuck 9 may form one component,
or separate components. As the chucking/holding force, a negative
pressure, a Coulomb force, a magnetic force, or the like, is
preferably used.
[0050] The stage apparatus, according to the preferred embodiment
of the present invention, is characterized in the following
respects. Namely, as shown in FIG. 1, the wafer chuck 9 is
supported through the projection support 11, the distal end of the
projection support 11 to come into contact with the wafer chuck
support surface 13 is spherical, and the V-groove 12 is formed in
the wafer chuck support surface 13, so that the projection support
11 and the V-groove 12 of the wafer chuck support surface 13 come
into point contact with each other. The stage apparatus is also
characterized in that the chucking/holding force acting on the
fixing member 14 fixes only the projection support 11.
[0051] FIG. 2 is an enlarged view of a portion in the vicinity of
the projection support 11 for the wafer chuck 9. In FIG. 2, if
there are three projection supports, the wafer chuck 9 is held at
six points. As the projection support 11 and the V-groove 12 are in
point contact with each other, no moment force is generated at the
contact portion. The fixing member 14 also has a mechanism that
applies no moment force to the projection support 11. The
projection support 11 comes into contact with the V-groove 12 at a
plurality of points (in this case, two points per projection
support), so that the force acting on the projection support 11 can
be dispersed. Therefore, deformation caused by contact stress is
largely decreased when compared to a case wherein the projection
support 11 is in contact with the V-groove 12 at one point. Since
the contact area is small, dust is caught in the contact area at a
low possibility.
[0052] Although the V-groove 12 of this embodiment has a V shape,
the present invention is not limited to this. For example, any
V-groove 12 will do as long as it is formed of two surfaces
including an inclined surface and the projection support 11 slides
on it by the weight of the wafer chuck 9 so that the position of
the projection support 11 is determined. The open angle formed by
the two surfaces may be 90.degree., or more than that, or less than
that. The projection support 11, which comes into contact with the
V-groove 12 of the wafer chuck support surface 13, preferably has a
shape (e.g., a spherical shape) with which the contact portion of
projection support 11 and the V-groove 12 of the wafer chuck
support surface 13 forms point contact. If the moment force is
small, the projection support 11 and wafer chuck support surface 13
may be formed to come into linear contact or surface contact with
each other.
[0053] In this embodiment, the wafer chuck 9 has the projection
support 11, and the V-groove 12 is formed on a stage 10. However,
the present invention is not limited to this. For example, the
relationship between the projection support 11 on the lower surface
of the wafer chuck 9 and the V-groove 12 can be reversed. More
specifically, the projection support 11 may be formed on the wafer
chuck support surface 13, and the V-groove 12 may be formed in the
lower surface of the wafer chuck 9. In this case, the projection
support 11 for supporting the wafer chuck 9 is fixed to the wafer
chuck 9. When the chucking/holding force is canceled, the
projection support 11 can be released from the wafer chuck support
surface 13. The projection support 11 for supporting the wafer
chuck 9 may be fixed to the wafer chuck support surface 13. When
the chucking/holding force is canceled, the projection support 11
can be released from the wafer chuck 9.
Second Embodiment
[0054] A stage apparatus according to the second preferred
embodiment of the present invention is characterized in the
following respects. Namely, as shown in FIG. 3, in an X-Y stage
apparatus including a wafer chuck 9, which chucks and holds a wafer
8 by suction, caused by a negative pressure or a Coulomb force, the
surface of the wafer chuck 9 is supported on a wafer chuck support
surface 13 at three points, so that the surface of the wafer chuck
9 is supported stably.
[0055] The wafer chuck 9 has three projection supports 11. As shown
in FIG. 3, V-grooves 12 for receiving the respective projection
supports 11 are arranged on the wafer chuck support surface 13 in
three directions at an angular interval of about 1200. The position
of the wafer chuck 9 is uniquely determined by its own weight.
Hence, an abutment which is indispensable for positioning becomes
unnecessary, and the reproducibility of the support position can be
increased. When the wafer chuck 9 is supported and retained at
three points, the wafer chuck 9 can be fixed stably. Also, as the
wafer chuck 9 is supported at three points, the wafer chuck 9
conforms to the shape of the wafer chuck support surface 13 at a
lower possibility compared to a case wherein the wafer chuck 9 is
supported at its entire surface. Also, the possibility that
distortion, heat, or vibration, which occurs on the wafer chuck
support surface 13 in various manners during exposure or movement
of the wafer chuck 9, adversely affect deformation, or the like, of
the wafer chuck 9, decreases.
[0056] As described above, that the V-grooves 12 are arranged in
three directions at an angular interval of about 120.degree. and
that the projection supports 11 and the V-grooves 12 of the wafer
chuck support surface 13 come into point contact with each other
are very effective to stably support the wafer chuck 9.
[0057] A fixing member 14, which holds the projection support 11
against the wafer chuck support surface 13 with a force that chucks
and holds the wafer chuck 9 can define a closed space, when an
outer seal portion present on its outer surface comes into contact
with the wafer chuck support surface 13 with no gap. The fixing
member 14 preferably has one of a circular shape, an elliptical
shape, a shape similar to an ellipse, or a polygonal shape. The
chucking/holding force acting on the fixing member 14 is preferably
one of a negative pressure, a Coulomb force, and a magnetic force.
When the chucking/holding force is a negative pressure, a closed
space is needed. The suction force is obtained by vacuum (e.g.,
evacuation with a vacuum pump) from a vacuum hole (not shown) in
the closed space defined by the fixing member 14 and wafer chuck
support surface 13.
[0058] When leakage is prevented in the above manner, the
projection support 11 can be chucked reliably to the wafer chuck
support surface 13. The outer seal portion present on the outer
surface of the projection support 11 can be incorporated in the
following embodiments as well.
Third Embodiment
[0059] A stage apparatus according to the third preferred
embodiment of the present invention includes a wafer chuck 9, which
chucks and holds a wafer 8 with suction caused by a negative
pressure or the Coulomb force, as shown in FIG. 4. A projection
support 11, which supports the wafer chuck 9 and comes into contact
with a V-groove 12, forms one component together with a fixing
member 14. The projection support 11 to come into contact with the
V-groove 12 is not limited to the one which forms one component
together with the fixing member 14. For example, as shown in FIG.
5, the projection support 11 may be fixed to a fixing member 14 as
a separate component.
Fourth Embodiment
[0060] A stage apparatus according to the fourth preferred
embodiment of the present invention has a wafer chuck 9, which
chucks and holds a wafer 8 by suction caused by a negative pressure
or a Coulomb force. To prevent deformation of the surface of the
wafer chuck 9, which is caused by the shape of a wafer chuck
support surface 13, in this stage apparatus, a projection support
11 for supporting the wafer chuck 9 has an arrangement for
absorbing or avoiding deformation.
[0061] In the stage apparatus according to this embodiment, a
fixing member 14 can tilt freely at its contact portion in the
axial direction of the projection support 11 and in the planar
direction. When the fixing member 14 has the above degrees of
freedom at its contact portion, a small gap is present at the
contact portion of the projection support 11 and fixing member 14.
This small gap allows the fixing member 14 to move freely.
[0062] When the projection support 11 has a fixing member 14 with a
shape that ensures a wide surface area parallel to the wafer chuck
support surface 13, the fixing member 14 can move freely at the
contact portion with respect to the projection support 11.
[0063] As an example of the above arrangement, for example, in the
stage apparatus according to this embodiment, as shown in FIG. 6,
the fixing member 14 has a small gap 15 at the contact portion with
respect to the projection support 11. This gap 15 allows the
projection support 11 to move freely to a certain degree. The gap
15 has such a size that, when the fixing member 14 inclines with
respect to the projection support 11, the projection support 11
will not come into contact with the fixing member 14 with this
inclination. This arrangement can be applied to the following fifth
to ninth embodiments as well.
Fifth Embodiment
[0064] A stage apparatus according to the fifth embodiment of the
present invention has a fixing member 14 which holds only a
projection support 11 for a wafer chuck 9 with respect to a wafer
chuck support surface 13. As shown in FIG. 7, the fixing member 14
can elastically deform by a chucking/holding force as a negative
pressure. In this case, the fixing member 14 is preferably designed
with such a thickness that it can elastically deform by the suction
force. This arrangement can be one in which an elastic body or a
variable-length material is incorporated in the projection support
11, or one in which a variable-length mechanism is incorporated in
the projection support 11. When the fixing member 14 comes into
contact with the wafer chuck support surface 13 and is chucked and
held, the fixing member 14 is tilted to conform to the stage of the
wafer chuck support surface 13 at a high possibility. This,
however, does not adversely affect the projection support 11 with a
moment force or the like. This is because the moment force or the
like is absorbed by the contact portion of the fixing member 14
with respect to the projection support 11, or by the elastic
deformation of the fixing member 14 serving as the elastic
body.
Sixth Embodiment
[0065] A stage apparatus according to the sixth preferred
embodiment of the present invention is characterized in that, as
shown in FIGS. 8A and 8B, a fixing member 14 incorporates a rolling
mechanism 16 at its contact portion with respect to a projection
support 11, so that the fixing member 14 can move freely with
respect to the projection support 11. As the projection support 11
can vertically move smoothly with respect to the fixing member 14,
the projection support 11 can be reliably chucked to a wafer chuck
support surface 13 without any moment force from the fixing member
14.
Seventh Embodiment
[0066] A stage apparatus according to the seventh preferred
embodiment of the present invention is characterized in that, as
shown in FIGS. 9A and 9B, a fixing member 14 incorporates a
vertical slide mechanism 17 at its contact portion with respect to
a projection support 11, so that the fixing member 14 can move
freely with respect to the projection support 11 in the axial
direction of the projection support 11. The vertical slide
mechanism 17 is characterized in that it reduces frictional
resistance, so that its contact area is small and its contact
surface is smooth. Thus, the projection support 11 can be reliably
chucked to a wafer chuck support surface 13 without any moment
force from the fixing member 14.
Eighth Embodiment
[0067] A stage apparatus according to the eighth preferred
embodiment of the present invention is characterized in that, as
shown in FIGS. 10A and 10B, a fixing member 14 incorporates, at its
contact portion with respect to a projection support 11, a vertical
slide mechanism 17' having no contact portion, so that a projection
support 11 can move freely with respect to the fixing member 14.
For example, when the projection support 11 is fixed to the fixing
member 14 with springs 18, or the like, the projection support 11
can be reliably chucked to a wafer chuck support surface 13 without
any moment force from the fixing member 14.
Ninth Embodiment
[0068] A stage apparatus according to the ninth preferred
embodiment of the present invention is characterized in that, as
shown in FIGS. 11A and 11B, an elastic body 19 is provided at that
portion of a projection support 11, which comes into contact with a
fixing member 14, so that the projection support II can move
freely. Thus, the projection support 11 can be reliably chucked to
a wafer chuck support surface 13 without any moment force from the
fixing member 14.
Tenth Embodiment
[0069] A stage apparatus according to the tenth preferred
embodiment of the present invention is characterized in that, as
shown in FIGS. 12A and 12B, a seal member 20 is arranged between a
projection support 11 and fixing member 14 within a range not
limiting the degrees of freedom. As the seal member 20, for
example, an O-ring is used.
Eleventh Embodiment
[0070] A stage apparatus according to the eleventh preferred
embodiment of the present invention includes a wafer chuck 9 which
chucks and holds a wafer 8 by suction caused by a negative pressure
or the Coulomb force. The wafer chuck 9 is placed on a wafer chuck
support surface 13 through a projection support 11 which comes into
contact with the wafer chuck support surface 13, and is chucked and
placed by a negative pressure, the Coulomb force, or a magnetic
force.
[0071] Since the wafer chuck 9 must be fixed on the wafer chuck
support surface 13, not only is the wafer chuck 9 placed on the
wafer chuck support surface 13, but also a force is applied to the
projection support 11, which comes into contact with the wafer
chuck support surface 13, thereby fixing the wafer chuck 9. As this
force, a vacuum force, a Coulomb force, a magnetic force, or the
like, is used. A mechanism that generates such a force is
incorporated in the wafer chuck support surface 13 or the
projection support 11. The mechanism which generates the force
includes a mechanism such as a pump for generating a vacuum force,
an electrode for generating the Coulomb force, an electromagnet for
generating a magnetic force, and the like.
[0072] As described above, according to the present invention, a
large integrated device can be manufactured stably with high
productivity. With the stage apparatus according to the preferred
embodiment of the present invention and the wafer chuck
incorporated in it, the wafer chuck can be stationarily held on and
removed from the support surface of the wafer chuck
instantaneously. Thus, only the projection support can be held and
fixed without applying any forces to the wafer chuck. The
reproducibility of the surface of the wafer chuck on different
stages can thus be obtained.
[0073] As described above, with the stage apparatus according to
the preferred embodiment of the present invention, problems
accompanying the increase in diameter of the wafer, high-speed
movement of the wafer chuck, and the like, are solved, so that the
throughput can be improved.
Other Embodiment
[0074] [Exposure Apparatus]
[0075] An example will be described wherein a stage apparatus
according to a preferred embodiment of the present invention is
applied to a reduction projection exposure apparatus.
[0076] FIG. 13 is a conceptual view showing the arrangement of an
exposure apparatus according to a preferred embodiment of the
present invention. As shown in FIG. 13, in this exposure apparatus,
a reticle 2 as an exposure master is placed on a reticle stage 4,
and is irradiated with exposure light guided from a light source
(not shown) through an illumination optical system 1. The exposure
light passing through the reticle 2 is reduced to one-fifth by a
projection optical system 5, to irradiate a silicon substrate
(wafer) or a wafer 8 as an object to be processed. As wafer chuck 9
serving as a substrate holding unit for holding the wafer 8 is
placed on a stage 10, which can move the wafer 8 within a
horizontal plane.
[0077] [Exposure Sequence]
[0078] The exposure sequence of the exposure apparatus will be
described. After the wafer 8 as the exposure target is set in the
exposure apparatus automatically or manually, the exposure
apparatus starts operation upon reception of an exposure start
command. First, the wafer 8 is transported onto the wafer chuck 9
placed on the stage 10 by a transport system. Subsequently, a
plurality of alignment marks on the wafer 8 are detected and
measured by an off-axis scope 7 mounted on the stage 10. The
magnification, rotation, and X-Y error amounts of the wafer 8 are
determined, and the position of the wafer 8 is corrected. The stage
10 moves so as so to set the first shot position of the wafer 8
chucked and held by the wafer chuck 9 to coincide with the exposure
position. After the first shot position is focused by a surface
measuring means 6, it is exposed for about 0.2 sec. The off-axis
scope 7 steps to the second shot position on the wafer 8, and
exposure is sequentially repeated. This sequence is performed
repeatedly. When the final shot process is ended, an exposure
process for one wafer 8 is completed. The wafer 8 is transferred
from the wafer chuck to a recovery transport band, and is returned
to the wafer carrier.
[0079] [Semiconductor Device Manufacturing Process]
[0080] A semiconductor device manufacturing process utilizing the
above exposure apparatus will be described. FIG. 14 is a flow chart
of the flow of the overall semiconductor device manufacturing
process. In step 1 (circuit design), circuit design of a
semiconductor device is performed. In step 2 (mask fabrication), a
mask is fabricated based on the designed circuit pattern. In step 3
(wafer fabrication), a wafer is manufactured by using a material
such as silicon. In step 4 (wafer process), called a pre-process,
an actual circuit is formed on the wafer by lithography by using
the mask and wafer described above. In step 5 (assembly), called a
post-process, a semiconductor chip is formed by using the wafer
fabricated in step 4, and includes processes such as an assembly
process (dicing and bonding) and a packaging process (chip
encapsulation). In step 6 (inspection), inspections such as the
operation confirmation test and durability test of the
semiconductor device fabricated in step 5 are performed. After
these steps, the semiconductor device is completed, and shipped
(step 7).
[0081] FIG. 15 is a flow chart showing the detailed flow of the
wafer process. In step 11 (oxidation), the surface of the wafer is
oxidized. In step 12 (CVD), an insulating film is formed on the
wafer surface. In step 13 (electrode formation), an electrode is
formed on the wafer by vapor deposition. In step 14 (ion
implantation), ions are implanted in the wafer. In step 15 (resist
processing), a photosensitive agent is applied to the wafer. In
step 16 (exposure), the circuit pattern is transferred to the wafer
by using the above exposure apparatus. In step 17 (development),
the exposed wafer is developed. In step 18 (etching), the resist is
etched except for the developed resist image. In step 19 (resist
removal), an unnecessary resist after etching is removed. These
steps are repeated to form multiple circuit patterns on the
wafer.
[0082] As described above, according to the present invention, the
throughput can be improved.
[0083] As many apparently widely different embodiments of the
present invention can be made without departing from the spirit and
scope thereof, it is to be understood that the invention is not
limited to the specific embodiments thereof except as defined in
the claims.
* * * * *