U.S. patent application number 13/471573 was filed with the patent office on 2012-09-06 for imprinting device and imprinting method.
This patent application is currently assigned to SCIVAX CORPORATION. Invention is credited to Yuji Hashima, Yoshihisa Hayashida, Akihiko Kanai, Hirosuke Kawaguchi, Yoshiaki Takaya, Satoru Tanaka, Kazuaki Uehara.
Application Number | 20120223461 13/471573 |
Document ID | / |
Family ID | 40800903 |
Filed Date | 2012-09-06 |
United States Patent
Application |
20120223461 |
Kind Code |
A1 |
Takaya; Yoshiaki ; et
al. |
September 6, 2012 |
IMPRINTING DEVICE AND IMPRINTING METHOD
Abstract
The present invention provides an imprinting device and an
imprinting method which can uniformly apply pressure between a mold
and a molding object and which can increase and decrease a
temperature at a fast speed. An imprinting device is for
transferring a pattern on a mold to a film molding object, and
comprises a stage for holding the mold, a pressurizing-chamber
casing which configures a pressurizing-chamber together with the
molding object, sealing means which airtightly seals a space
between the pressurizing-chamber casing and the molding object,
opening and closing means which opens and closes the space between
the pressurizing-chamber casing and the molding object,
pressurizing means which adjusts atmospheric pressure in the
pressurizing-chamber, heating means which heats either one of or
both of the mold and the molding object, and degassing means which
eliminates any gas present between the mold and the molding
object.
Inventors: |
Takaya; Yoshiaki; (Chiba,
JP) ; Hashima; Yuji; (Chiba, JP) ; Hayashida;
Yoshihisa; (Chiba, JP) ; Kawaguchi; Hirosuke;
(Kanagawa, JP) ; Tanaka; Satoru; (Kanagawa,
JP) ; Kanai; Akihiko; (Kanagawa, JP) ; Uehara;
Kazuaki; (Kanagawa, JP) |
Assignee: |
SCIVAX CORPORATION
Kanagawa
JP
|
Family ID: |
40800903 |
Appl. No.: |
13/471573 |
Filed: |
May 15, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12810557 |
Sep 17, 2010 |
8215944 |
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PCT/JP2008/003953 |
Dec 25, 2008 |
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13471573 |
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Current U.S.
Class: |
264/402 ;
264/102; 264/405 |
Current CPC
Class: |
B29C 2059/023 20130101;
B29C 59/022 20130101; B29C 33/42 20130101; G03F 7/0002 20130101;
B82Y 40/00 20130101; B82Y 10/00 20130101; B29C 2035/0822
20130101 |
Class at
Publication: |
264/402 ;
264/102; 264/405 |
International
Class: |
B29C 59/02 20060101
B29C059/02; B29C 35/08 20060101 B29C035/08 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 26, 2007 |
JP |
2007-335093 |
Claims
1-7. (canceled)
8. An imprinting method of transferring a pattern on a mold to a
film molding object, comprising a steps of: superimposing the
molding object on the mold; eliminating a gas present between the
mold and the molding_object by reducing a pressure inside a vacuum
chamber where the mold and the molding object are arranged; and
heating the molding object to a temperature equal to or higher than
a glass transition temperature, and directly pressing the molding
object against the mold by a gas in order to transfer the
pattern.
9. An imprinting method of transferring a pattern on a film mold to
a molding object, comprising a steps of: superimposing the molding
object on the mold; eliminating a gas present between the mold and
the molding object by reducing a pressure inside a vacuum chamber
where the mold and the molding object are arranged; and heating the
molding object to a temperature equal to or higher than a glass
transition temperature, and directly pressing the mold against the
molding object by a gas in order to transfer the pattern.
10. (canceled)
11. The imprinting method according to claim 8, further comprising
a step of heating either one of or both of the mold and the molding
object by irradiation of electromagnetic waves.
12. The imprinting method according to claim 8, further comprising
a step of heating either one of or both of the mold and the molding
object by a gas at a predetermined temperature.
13. The imprinting method according to claim 9, further comprising
a step of heating either one of or both of the mold and the molding
object by irradiation of electromagnetic waves.
14. The imprinting method according to claim 9, further comprising
a step of heating either one of or both of the mold and the molding
object by a gas at a predetermined temperature.
Description
TECHNICAL FIELD
[0001] The present invention relates to an imprinting device and an
imprinting method with high throughput.
BACKGROUND ART
[0002] Recently, thermal nanoimprinting technologies are getting
attention as technologies of forming an ultra-fine pattern in a
micro order or in a nano order. According to such technologies, a
molding object like a substrate or a film formed of a resin with
thermal plasticity is heated to a temperature equal to the glass
transition temperature of the resin or higher, and a fine pattern
is pressed against the molding object, thereby transferring the
pattern.
[0003] According to such nanoimprinting technologies, parallelism
between the mold and the molding object and flatness are important
factors. If the mold and the molding object are not parallel to
each other, pressure applied thereto becomes nonuniform, so that
stress may be applied locally and the molding object may be
deformed or damaged, resulting in transfer failure of the
pattern.
[0004] In order to overcome such a problem, conventionally, there
are proposed a device which has an elastic member arranged at the
rear of the mold (see, for example, patent literature 1), and a
device which hydraulically pressurizes the mold via a flexible film
(see, for example, patent literature 2).
[0005] Patent Literature 1: International Publication No.
WO2007/049530
[0006] Patent Literature 2: International Publication No.
WO01/042858
DISCLOSURE OF INVENTION
Problem to be Solved by the Invention
[0007] According to those devices, however, a problem originating
from the parallelism between the mold and the molding object and
the flatness is not sufficiently resolved. Moreover, conventional
devices have a stage or the like holding the molding object between
a heater and the molding object, and large amount of heat is
requisite for this, so that it takes a lot of time for heating and
cooling. Such problem becomes further noticeable as the device
becomes large.
[0008] Therefore, it is an object of the present invention to
provide an imprinting device and an imprinting method which can
uniformly apply pressure between a mold and a molding object and
which can increase/reduce a temperature at a fast speed.
Means for Solving the Problem
[0009] To achieve the object, a first imprinting device of the
present invention transfers a pattern on a mold to a film molding
object, and the imprinting device comprises: a stage for holding
the mold; a pressurizing-chamber casing which configures a
pressurizing chamber together with the molding object; sealing
means which airtightly seals a space between the
pressurizing-chamber casing and the molding object; opening/closing
means which opens/closes the space between the pressurizing-chamber
casing and the molding object; pressurizing means which adjusts
atmospheric pressure in the pressurizing chamber; and heating means
which heats either one of or both of the mold and the molding
object.
[0010] A second imprinting device of the present invention
transfers a pattern on a film mold to a molding object, and the
imprinting device comprises: a stage for holding the molding
object; a pressurizing-chamber casing which configures a
pressurizing chamber together with the mold; sealing means which
airtightly seals a space between the pressurizing-chamber casing
and the mold; opening/closing means which opens/closes the space
between the pressurizing-chamber casing and the mold; pressurizing
means which adjusts atmospheric pressure in the pressurizing
chamber; and heating means which heats either one of or both of the
mold and the molding object.
[0011] In this case, it is preferable that the imprinting device
should further comprise degassing means which eliminates a gas
present between the mold and the molding object. Moreover, the
heating means may perform heating by irradiation of electromagnetic
waves, or may supply a gas heated at a predetermined temperature to
the pressurizing-chamber casing. Furthermore, it is preferable that
the imprinting device should further comprise cooling means which
cools the molding object.
[0012] In the second imprinting device, the mold may be a film mold
used at a predetermined molding temperature, the film mold
comprising a base layer formed of a thermoplastic resin and a hard
layer formed of a material harder than the thermoplastic resin at
the molding temperature and formed at a molding face side of the
base layer.
[0013] A first imprinting method of the present invention transfers
a pattern on a mold to a film molding object, and comprises a step
of: directly pressing the molding object against the mold by a
gas.
[0014] A second imprinting method of the present invention
transfers a pattern on a film mold to a molding object, and
comprises a step of: directly pressing the mold against the molding
object by a gas.
[0015] In this case, it is preferable that a gas present between
the mold and the molding object should be eliminated before the
pattern on the mold is transferred. Moreover, either one of or both
of the mold and the molding object can be heated by irradiation of
electromagnetic waves or by a gas at a predetermined
temperature.
Effect of the Invention
[0016] According to the present invention, at least either one of
the mold or the molding object to be used is a flexible film, and
is directly pressed by a gas, so that pressure can be uniformly
applied between the mold and the molding object, thereby enabling
precise pattern transfer.
[0017] Moreover, because any intervening member present between the
mold or the molding object and the heating means can be eliminated,
the molding object can be subjected to fast-speed temperature
increasing/reduction by irradiation of electromagnetic waves or by
a gas at a predetermined temperature, thereby improving the
throughput.
BRIEF DESCRIPTION OF DRAWINGS
[0018] FIG. 1 is a schematic cross-sectional view showing a first
imprinting device of the present invention;
[0019] FIG. 2 is a schematic cross-sectional view showing the
imprinting device of the present invention with a vacuum chamber
being formed;
[0020] FIG. 3 is a schematic cross-sectional view showing a
condition in which a pressurizing chamber and the vacuum chamber
are opened;
[0021] FIG. 4 is a schematic cross-sectional view showing a second
imprinting device of the present invention; and
[0022] FIG. 5 is a schematic cross-sectional view showing a
film-type mold of the imprinting device of the present
invention.
DESCRIPTION OF REFERENCE NUMERALS
[0023] 1 Imprinting device
[0024] 2 Imprinting device
[0025] 11 Stage
[0026] 12 Pressurizing chamber
[0027] 13 Pressurizing-chamber casing
[0028] 14 Sealing means
[0029] 15 Opening/closing means
[0030] 16 Pressurizing means
[0031] 17 Heating means
[0032] 18 Degassing means
[0033] 100 Mold
[0034] 101 Base layer
[0035] 102 Hard layer
[0036] 200 Molding object
BEST MODE FOR CARRYING OUT THE INVENTION
[0037] An explanation will be given of embodiments of the present
invention with reference to the accompanying drawings.
First Embodiment
[0038] As shown in FIG. 1, a first imprinting device 1 of the
present invention is an imprinting device for transferring a
pattern on a mold 100 to a film-like molding object 200, and mainly
comprises a stage 11 for holding the mold 100, a
pressurizing-chamber casing 13 which configure a pressurizing
chamber 12 together with the molding object 200, sealing means 14
which airtightly seals a space between the pressurizing-chamber
casing 13 and the molding object 200, opening/closing means 15
which opens/closes the space between the pressurizing-room chamber
13 and the molding object 200, pressurizing means 16 for adjusting
an atmospheric pressure inside the pressurizing chamber 12, and
heating means 17 which heats the molding object 200. Moreover, it
is preferable that the imprinting device should further have
degassing means 18 which expels any gas from a space between the
mold 100 and the molding object 200.
[0039] The stage 11 is not limited to any particular one as far as
it can hold the mold 100, but for example, is formed in a planar
shape having a plane for holding the mold 100 larger than the mold
100, or has a recess which is formed in such a plane with a depth
substantially equal to the thickness of the mold and which can
retain the mold 100 thereinside. The material of the stage is not
limited to any particular one as far as it has pressure resistance
and heat resistance so as to withstand pressure and heat at the
time of molding, but it is preferable that such material should
have a thermal expansion coefficient similar to that of the mold
100. For example, when the mold 100 is formed of nickel, the
nickel-made stage 11 can be used. Moreover, it is preferable if the
mold 100 and the stage 11 are integrally formed together in order
to suppress any generation of unnecessary transfer mark on the
molding target 200. For example, according to the conventional
technologies, a pattern is formed by electroforming, and only the
patterned part is cut out and used, but such patterned part can be
used directly as it is without being cut out. Moreover, a holding
tool for holding the molding object 200 may be additionally
provided.
[0040] The pressurizing-chamber casing 13 is formed in a
cylindrical shape with an opened face, and configures the
pressurizing chamber 12 which is a sealed space as the opened face
is closed by the molding object 200. The opened face is so formed
as to be larger than at least a pattern area to be transferred to
the molding object 200. The material of the pressurizing-chamber
casing 13 is not limited to any particular one as far as it has
pressure resistance and heat resistance so as to withstand pressure
and heat at the time of molding, and for example, an iron material
like carbon steel or a metal like SUS can be used.
[0041] The sealing means 14 airtightly allows the
pressurizing-chamber casing 13 and the molding object 200
airtightly contact with each other in order to make the
pressurizing chamber 12 closed. For example, as shown in FIG. 1, an
O-ring 141 is prepared as the sealing means 14, a recessed groove
142 shallower than the diameter of the cross section of the O-ring
is formed in an end part of a side wall of the pressurizing-chamber
casing 13, and the O-ring 141 is fitted into the groove 142.
Accordingly, the molding object 200 is held between the
pressurizing-chamber casing 13 and the stage 11, and the
pressurizing-chamber casing 13 and the molding object 200 can
airtightly contact with each other, so that the pressurizing
chamber 12 can be airtightly closed. Moreover, even if there is an
inclination between the pressurizing-chamber casing 13 and the
molding object 200, when such parallelism is within the collapsible
range of the O-ring 141, the pressurizing chamber 12 can be surely
closed.
[0042] The opening/closing means 15 opens/closes the pressurizing
chamber 12 by causing the pressurizing-chamber casing 13 and the
molding object 200 to move close or to move apart relative to each
other, and for example, a system having a hydraulic or pneumatic
cylinder moving the pressurizing-chamber casing 13, or a system
having an electric motor and a ball screw moving the
pressurizing-chamber casing may be used.
[0043] The pressurizing means 16 is not limited to any particular
one as far as it can adjust atmospheric pressure in the
pressurizing chamber 12 up to pressure which enables transfer of a
pattern on the mold 100 to the molding object 200, and for example,
a pressurizing-chamber inlet/outlet path 161 is connected to the
pressurizing-chamber casing 13, and a gas, such as air or an
inactive gas is supplied to or expelled from the pressurizing
chamber 12 through the pressurizing-chamber inlet/outlet path 161.
A cylinder 162 (see FIG. 1) containing compressed gas thereinside
or a pressurizing pump can be used to supply such gas. Moreover,
such gas can be expelled by opening/closing of a degassing valve
163. Note that a safety valve or the like may be additionally
provided as needed.
[0044] The heating means 17 is not limited to any particular one as
far as it can heat either one of or both of the mold 100 and the
molding object 200 to a temperature equal to the glass transition
temperature of the molding object or higher, or, a temperature
equal to the melting temperature or higher, and for example, a
heater is provided at the stage 11 side to heat the mold 100 and
the molding object 200 from the stage 11 side. Moreover, one
provided in the pressurizing chamber 12 and heating the mold 100 or
the molding object 200 by irradiation with electromagnetic waves
like far infrared rays may be used. For example, a ceramic heater
or a halogen heater provided at the pressurizing chamber 12 side of
the pressurizing-chamber casing 13 may be used. According to such a
structure, unlike the conventional devices, because there is no
intervening member like the stage 11 or a film between the heating
means 17 and the molding object 200, the thermal capacity can be
reduced, and the mold object 200 can be heated at a fast speed with
minimal heat quantity. This also enables fast-speed cooling.
Moreover, the gas supplied by the pressurizing means may be heated
beforehand and the molding object may be heated by such heated gas.
Needless to say, the heating means 17 may be a combination of such
structures. Note that a heat insulating material 171 may be
provided between the pressurizing-chamber casing 13 and the heating
means 17. Moreover, the temperature of the mold 100 and that of the
molding object 200 may be detected by temperature detecting means
like a thermocouple sensor, and the heating means 17 may be
controlled by a control means (not illustrated) like a temperature
controller to adjust the temperature.
[0045] The degassing means 18 eliminates any gas present between
the mold 100 and the molding object 200. The reason why it is
preferable to have the degassing means 18 is that if any gas is
present between the mold 100 and the molding object 200, it becomes
difficult to presses the mold 100 and the molding object 200
against each other and heating becomes nonuniform, resulting in a
transfer failure. As an example of the degassing means 18, for
example, a vacuum chamber 181 which contains at least the mold 100
and the molding object 200 thereinside is formed, and the interior
of the vacuum chamber 181 is subjected to pressure reduction to
eliminate any gas present between the mold 100 and the molding
object 200.
[0046] The vacuum chamber 181 comprises, for example, a ceiling
member 182 which covers the top of the pressurizing-chamber casing
13, bellows 183 so provided as to be hung on the ceiling member 182
and to cover the side of the pressurizing-chamber casing 13, a seal
member 184 which seals a space between the bellows 183 and the
stage 11 or a base 10 where the stage 11 is mounted, and a vacuum
pump 185 which evacuates any gas in the vacuum chamber 181 through
a vacuum-chamber inlet/outlet path. The seal member 184 is fitted
in a recessed groove formed in the bellows 183 at the stage 11
side. It is appropriate if the vacuum pump is capable of reducing
the pressure of the vacuum chamber 181 to a condition in which no
transfer failure occurs when the molding object 200 is pressed
against the mold 100. The ceiling member 182 is so formed as to be
movable by the opening/closing means 15. It is needless to say that
the ceiling member 182, the bellows 183, and the seal member 184
must have strength capable of withstanding external force under a
vacuum condition.
[0047] As shown in FIG. 1, the above-explained pressurizing-chamber
inlet/.outlet path may serve as the vacuum-chamber inlet/outlet
path in common. In this case, as shown in FIG. 2, first, with the
pressurizing chamber 12 being opened, gases in the vacuum chamber
181 and the pressurizing chamber 12 are evacuated to eliminate any
gas present between the mold 100 and the molding object 200. Next,
as shown in FIG. 1, the pressurizing chamber 12 is closed by the
opening/closing means 15, gas is supplied to the pressurizing
chamber 12 and then the molding object 200 is pressed against the
mold 100.
[0048] The imprinting device may further comprise cooling means.
The cooling means is not limited to any particular one as far as it
can cool down the mold 100 and the molding object 200, but for
example, a fan which supplies air or gas like an inactive gas at a
temperature lower than that of the molding object 200 to the
molding object 200 and the mold 100 can be used. Moreover,
substituting means which substitutes gas in the pressurizing
chamber 12 with a cooling gas may be used. Furthermore, a cooling
path formed of a metal with high thermal conductivity, such as
aluminum or copper, may be formed in the stage 11, and a coolant
like water or oil, or, a cooling gas like an inactive gas may be
allowed to flow through the interior of the cooling path.
[0049] As the molding object 200, various kinds of materials can be
used as far as it can deform in accordance with the shape of the
mold 100 or the like at a molding temperature by pressure from the
pressurizing chamber 12 side. Examples of such material are resins,
such as polycarbonate, polyimide, polytetrafluoroethylene (PTFE),
polyethylene, polystyrene, polypropylene, paraffin, and a
cyclic-olefin-based thermoplastic resin, and, a metal like
aluminum. If such a material is a thermoplastic material, a
material in an arbitrary shape, such as tabular, a sheet, or a film
can be used appropriately. It is appropriate if the thermoplastic
material having a thickness of equal to 1 mm or less is used in
order to accomplish the effect of the present invention, in
particular, a sheet film having a thickness of equal to 500 .mu.m
or less is preferable, and the thinner the film thickness becomes
like 200 .mu.m, 100 .mu.m, and 50 .mu.m, the more the effect of the
present invention can be accomplished remarkably.
[0050] The mold 100 is formed of, for example, "a metal like
nickel", "ceramic", "a carbon material like glass-like carbon", or
"silicon", and has a predetermined pattern formed in one end face
(molding face). This pattern can be formed by precision machining
performed on the molding face. Moreover, such pattern can be formed
by semiconductor microfabrication technologies like etching
performed on a silicon substrate, or by forming a metallic plating
on a surface of the silicon substrate or the like by
electroforming, e.g., nickel plating, and by peeling the metallic
plating layer. Furthermore, such pattern can be formed by
imprinting technologies like a film mold 100 to be discussed later.
Needless to say, the material and the production technique of the
mold 100 are not limited to any particular ones as far as a fine
pattern can be formed. The width of the pattern (the size of the
molding face in the planar direction) depends on the kind of the
molding object 200 to be used, but is formed in various sizes, such
as equal to 100 .mu.m or smaller, equal to 10 .mu.m or smaller,
equal to 2 .mu.m or smaller, equal to 1 .mu.m or smaller, equal to
100 nm or smaller, and equal to 10 nm or smaller. Moreover, the
depth the size in a direction orthogonal to the molding face 100a)
of such a pattern is formed in various sizes, such as equal to 10
nm or larger, equal to 100 nm or larger, equal to 200 nm or larger,
equal to 500 nm or larger, equal to 1 .mu.m or larger, equal to 10
.mu.m or larger, and equal to 100 .mu.m or larger. Furthermore, the
pattern can have various aspect ratios, such as equal to 0.2 or
larger, equal to 0.5 or larger, equal to 1 or larger, and equal to
2 or larger.
[0051] Because the mold 100 is heated and cooled during an
imprinting process, it is preferable that the mold should be made
thin as much as possible in order to make the thermal capacity
small.
[0052] Next, an explanation will be given of an imprinting method
of transferring a pattern on the mold 100 to a film molding object
200.
[0053] <Step 1>
[0054] The mold 100 having a pattern that is an inverted pattern to
be transferred to the molding object 200 is prepared, and fixed on
the stage 11. The film molding object 200 is arranged on the mold
100 (see FIG. 3).
[0055] <Step 2>
[0056] Gases present between the mold 100 and the molding object
200 are eliminated by the degassing means 18. For example, with the
pressurizing chamber 12 being opened, the seal member of the
bellows 183 is caused to abut the base 10 to form the vacuum
chamber 181 (see FIG. 2). Air in the vacuum chamber 181 is
evacuated through the pressurizing-chamber inlet/outlet path 161
provided in the pressurizing chamber 12 by the vacuum pump. Note
that the seal member is caused to abut the base 10 by the elastic
force of the bellows, but may be fixed to the base by additional
fixing means.
[0057] <Step 3>
[0058] The pressurizing-chamber casing 13 is moved to the molding
object 200 side by the opening/closing means 15, and the O-ring the
sealing means 14) is caused to abut the molding object, thereby
configuring the pressurizing chamber 12 (see FIG. 1).
[0059] <Step 4>
[0060] The interior of the, pressurizing chamber 12 is pressurized
by the pressurizing means 16, and the molding object 200 is pressed
against the mold 100.
[0061] <Step 5>
[0062] The mold 100 or the molding object 200 is heated by the
heating means 17 equal to or higher temperature that enables the
molding object 200 to do fluid migration (e.g., the glass
transition temperature of the resin). For example, using a
far-infrared heater provided at the ceiling of the
pressurizing-chamber casing 13, the mold 100 or the molding object
200 is directly heated. Note that the explanation was given of a
case in which heating is performed after pressurizing, but the
order of step 4 and step 5 may be inverted, and pressurizing may be
carried out after heating.
[0063] <Step 6>
[0064] After a predetermined time is elapsed which is sufficient
for transferring of the pattern on the mold 100 to the molding
object 200, heating by the heating means 17 is terminated, and the
molding object 200 is cooled by the cooling means.
[0065] <Step 7>
[0066] After the pressure of the interior of the pressurizing
chamber 12 is reduced up to an atmospheric pressure, the
pressurizing chamber 12 and the vacuum chamber 181 are opened, and
the mold 100 is released from the molding object 200. When the
cooling means which substitutes the gas in the pressurizing chamber
12 with a cooling gas is used, it is possible to carry out both
cooling and pressure reduction simultaneously.
[0067] Accordingly, any excessive intervening member present
between the mold 100 and the molding object 200 in the case of the
conventional technologies can be eliminated, so that it becomes
possible to uniformly apply pressure between the mold 100 and the
molding object 200, and to carry out heating and cooling at a fast
speed.
Second Embodiment
[0068] As shown in FIG. 4, a second imprinting device 2 of the
present invention is an imprinting device for transferring a
pattern on a film mold 100 to a molding object 200, and mainly
comprises a stage 11 which holds the molding object 200, a
pressurizing-chamber casing 13 which configures a pressurizing
chamber 12 together with the mold 100, sealing means 14 which
airtightly seals a space between the pressurizing-chamber casing 13
and the mold 100, degassing means 18 which eliminates any gas
present between the mold 100 and the molding object 200,
opening/closing means 15 which opens/closes the space between the
pressurizing-chamber casing 13 and the mold 100, heating means 17
which heats the molding object 200, and pressurizing means 16 which
adjusts atmospheric pressure in the pressurizing chamber 12.
[0069] That is, the second imprinting device 2 of the present
invention corresponds to the first imprinting device 1 of the
present invention using the film mold 100 and swaps respective
positions of the mold 100 and the molding object 200.
[0070] The stage 11 is not limited to any particular one as far as
it can hold the molding object 200, but for example, a surface
holding the molding object 200 is so formed as to be a larger plane
than the molding object 200, or a recess having a depth
substantially equal to the thickness of the molding object 200 and
capable of retaining the molding object 200 thereinside is formed
in such a plane. The material of the stage 11 is not limited to any
particular one as far as it has pressure resistance and heat
resistance so as to withstand pressure and heat at the time of
molding, but it is preferable that a material having a similar
thermal expansion coefficient to that of the molding object 200
should be used.
[0071] The pressurizing-chamber casing 13 is formed in a
cylindrical shape with an opened face, and configures the
pressurizing chamber 12 which is a sealed space as the opened face
is closed by the mold 100. The opened face is so formed as to be
larger than at least a pattern area to be transferred to the
molding object 200. The material of the pressurizing-chamber casing
13 is not limited to any particular one as far as it has pressure
resistance and heat resistance so as to withstand pressure and heat
at the time of molding, and for example, an iron material like
carbon steel or a metal like SUS can be used.
[0072] The sealing means 14 allows the pressurizing-chamber casing
13 and the mold 100 to airtightly contact with each other in order
to make the pressurizing chamber 12 closed. For example, as shown
in FIG. 4, an O-ring is prepared as the sealing means 14, a
recessed groove shallower than the diameter of the cross section of
the O-ring is formed in an end part of a side wall of the
pressurizing-chamber casing 13, and the O-ring 141 is fitted into
the groove. Accordingly, the mold 100 is held between the
pressurizing-chamber casing 13 and the stage 11, and the
pressurizing-chamber casing 13 and the mold 100 can airtightly
contact with each other, so that the pressurizing chamber 12 can be
airtightly closed. Moreover, even if there is an inclination
between the pressurizing-chamber casing 13 and the mold 100, when
such parallelism is within the collapsible range of the O-ring, the
pressurizing chamber 12 can be surely closed.
[0073] The opening/closing means 15 opens/closes the pressurizing
chamber 12 by causing the pressurizing-chamber casing 13 and the
mold 100 to move close or to move apart relative to each other, and
for example, a system having a hydraulic or pneumatic cylinder
moving the pressurizing-chamber casing 13, or a system having an
electric motor and a ball screw moving the pressurizing-chamber
casing may be used.
[0074] The pressurizing means 16, the heating means 17, the
degassing means 18, and the cooling means can employ the same
structure as that of the foregoing first imprinting device, so that
duplicated explanation thereof will be skipped in the present
embodiment.
[0075] Various kinds of mold 100 used for the imprinting device 2
can be used as far as it is a film which can deform in accordance
with the shape of the molding object 200 by pressure from the
pressurizing chamber 12 side, and for example, as shown in FIG. 5,
one having a base layer 101 with a predetermined pattern 103 and a
hard layer 102 formed on the pattern 103 can be used.
[0076] The base layer 101 is formed of a film of thermoplastic
resin, such as cyclic-olefin-based resins, e.g., a cyclic-olefin
ring-opening polymerization/hydrogenerated body (COP) and
cyclic-olefin copolymer (COC), acrylic resins, and resins based on
polycarbonate, vinyl-ether, perfluoroalkoxyalkane (PFA),
polytetrafluoroethylene (PTFE), polystyrene, polyimide and the
like. From the standpoint of dimensional stability of the pattern,
it is preferable that the thermoplastic resin used for the base
layer 101 should have a water absorption rate equal to 3% or
less.
[0077] The base layer 101 has the predetermined pattern 103. Such
pattern 103 can be formed through any technique, but for example,
nanoimprinting technologies like thermal imprinting can be applied.
The pattern 103 includes a geometric shape comprised of concavities
and convexities, one for transferring a predetermined surface
condition like transferring of a mirror-surface condition with
predetermined surface roughness, and one for transferring an
optical device like lens with predetermined curved surfaces.
[0078] The pattern 103 can be easily formed even if the minimum
size of the width of a convex and the width of a concavity is equal
to 100 .mu.m or smaller. The width of the pattern 103 (the size in
the planar direction) is formed in various sizes depending on the
kind of the molding object 200 to be used, such as equal to 100
.mu.m or smaller, equal to 10 .mu.m or smaller, equal to 2 .mu.m or
smaller, equal to 1 .mu.m or smaller, equal to 100 nm or smaller,
and equal to 10 nm or smaller.
[0079] Moreover, the size of the pattern 103 in the depth direction
is formed in various sizes, such as equal to 10 nm or larger, equal
to 100 nm or larger, equal to 200 nm or larger, equal to 500 nm or
larger, equal to 1 .mu.m or larger, equal to 10 .mu.m or larger,
and equal to 100 .mu.m or larger. Furthermore, the aspect ratio of
the pattern 103 is set to be various ratios, such as equal to 0.2
or larger, equal to 0.5 or larger, equal to 1 or larger, and equal
to 2 or larger.
[0080] The base layer 101 is so formed as to have a thickness which
enables the base layer 101 to deform in accordance with the shape
or the like of the molding object 200 by pressure from the
pressurizing chamber 12 side at a molding temperature.
[0081] Because the mold 100 is heated and cooled during an
imprinting process, it is preferable that the mold should be made
thin as much as possible in order to make the thermal capacity
small. For example, the mold is formed in a size equal to 50 .mu.m
or smaller, preferably, equal to 100 .mu.m or smaller, but the size
of the mold is not limited to those example sizes.
[0082] The hard layer 102 is formed of a material harder than the
thermoplastic resin used for the base layer 101 when the mold 100
is heated to a molding temperature for thermal imprinting and
pressed against the molding object 200. In consideration of the
molding temperature in thermal imprinting, it is preferable that a
material harder than the thermoplastic resin used for the base
layer 101 at least within a range from equal to 0.degree. C. or
higher to equal to 100.degree. C. or lower should be used. Examples
of such material are a metal and an inorganic material which are
solid substances at least within a range from equal to 0.degree. C.
or higher to equal to 100.degree. C. or lower. For example, a metal
or a metal compound, such as platinum (Pt), nickel (Ni), palladium,
ruthenium, gold, silver, copper, ZnO, or indium tin oxide (ITO),
or, an inorganic material like Si or SiO.sub.2 can be used.
Needless to say, other materials, e.g., a fluorine-based resin
which is a harder material than the base layer 101 at least within
a range from equal to 0.degree. c or higher to equal to 100.degree.
C. or lower can be used. Regarding the hardness, for example, it is
appropriate if Vickers hardness or Brinell hardness is compared
using a high-temperature hardness tester or the like. Such hardness
can be checked by a test through nano-indentation.
[0083] If the thickness of the hard layer 102 is too thick, the
pattern 103 of the base layer 101 is buried, so that it is
preferable that the hard layer should be made thin as much as
possible within a range in which the strength can be ensured, and
for example, is formed in a size equal to 100 mn or smaller. The
hard layer 102 can be formed of plural layers made of different
materials in accordance with its application.
[0084] How to form the hard layer 102 is not limited to any
particular technique, but for example, the foregoing material can
be deposited through chemical vapor deposition (CVD), physical
vapor deposition (PVD), or plating. For example, a metal like
platinum (Pt) or nickel (Ni) can be formed by sputtering or vapor
deposition. Moreover, the hard layer can be formed by silver mirror
reaction. When a fluorine-based resin is used, a solution in which
the material is dissolved can be dropped onto the pattern 103 of
the base layer 101 by spin coating, or the base layer 101 can be
dipped in the solution in which the material is dissolved.
[0085] Various kinds of molding object 200 can be used, and for
example, resins, such as polycarbonate, polyimide,
polytetrafluoroethylene (PTFE), polyethylene, polystyrene,
polypropylene, paraffin, and a cyclic-olefin-based thermoplastic
resin can be used. The molding object 200 in various shapes, such
as a film, a substrate, or a thin film formed on a substrate, can
be used.
[0086] Next, an explanation will be given of an imprinting method
of transferring a pattern on the film mold 100 to the molding
object 200.
[0087] <Step 1>
[0088] The molding object 200 is prepared and fixed on the stage
11. The film mold 100 having a pattern that is an inverted pattern
to be transferred to the molding object 200 is arranged on the
molding object 200.
[0089] <Step 2>
[0090] Gases present between the mold 100 and the molding object
200 are eliminated by the degassing means 18. For example, with the
pressurizing chamber 12 being opened, the seal member of the
bellows 183 is caused to abut the base 10 to form the vacuum
chamber 181. Air in the vacuum chamber 181 is evacuated through the
pressurizing-chamber inlet/outlet path 161 provided in the
pressurizing chamber 12 by the vacuum pump. Note that the seal
member is caused to abut the base 10 by the elastic force of the
bellows, but may be fixed to the base by additional fixing
means.
[0091] <Step 3>
[0092] The pressurizing-chamber casing 13 is moved to the mold 100
side by the opening/closing means 15, and the O-ring (the sealing
means 14) is caused to abut the mold 100, thereby configuring the
pressurizing chamber 12 (see FIG. 4).
[0093] <Step 4>
[0094] The interior of the pressurizing chamber 12 is pressurized
by the pressurizing means 16, and the mold 100 is pressed against
the molding object 200.
[0095] <Step 5>
[0096] The molding object 200 is heated by the heating means 17
equal to or higher temperature that enables the molding object 200
to do fluid migration (e.g., the glass transition temperature of
the resin). For example, using a far-infrared heater provided at
the ceiling of the pressurizing-chamber casing 13, the mold 100 or
the molding object 200 is directly heated. Note that the
explanation was given of a case in which heating is performed after
pressurizing, but the order of step 4 and step 5 may be inverted,
and pressurizing may be carried out after heating.
[0097] <Step 6>
[0098] After a predetermined time is elapsed which is sufficient
for transferring of the pattern on the mold 100 to the molding
object 200, heating by the heating means 17 is terminated, and the
molding object 200 is cooled by the cooling means.
[0099] <Step 7>
[0100] After the pressure of the interior of the pressurizing
chamber 12 is reduced up to an atmospheric pressure, the
pressurizing chamber 12 and the vacuum chamber 181 are opened, and
the molding object 200 is released from the mold 100. When the
cooling means which substitutes the gas in the pressurizing chamber
12 with a cooling gas is used, it is possible to carry out both
cooling and pressure reduction simultaneously.
[0101] Accordingly, any excessive intervening member present
between the mold 100 and the molding object 200 in the case of the
conventional technologies can be eliminated, so that it becomes
possible to uniformly apply pressure between the mold 100 and the
molding object 200, and to carry out heating and cooling at a fast
speed. Moreover, a pattern can be transferred even if the molding
object 200 is a substrate-like material.
* * * * *