U.S. patent application number 11/256079 was filed with the patent office on 2006-04-27 for constant-temperature fluid supply system.
Invention is credited to Takkaki Honda, Tetsuro Nishiyama, Hideo Saito, Hideki Takekuma, Satoshi Yasuda.
Application Number | 20060086114 11/256079 |
Document ID | / |
Family ID | 36204924 |
Filed Date | 2006-04-27 |
United States Patent
Application |
20060086114 |
Kind Code |
A1 |
Nishiyama; Tetsuro ; et
al. |
April 27, 2006 |
Constant-temperature fluid supply system
Abstract
A constant-temperature fluid supply system is provided with a
first constant-temperature fluid supply apparatus and a second
constant-temperature fluid supply apparatus. The first
constant-temperature fluid supply apparatus has an input side to
which a cooling fluid not controlled in temperature is supplied,
and an output side from which a first constant-temperature fluid
having a stable temperature is supplied. The second
constant-temperature fluid supply apparatus has an input side to
which the first constant-temperature fluid is supplied, and an
output side from which a second constant-temperature fluid having a
more stable temperature than that of the first constant-temperature
fluid is supplied.
Inventors: |
Nishiyama; Tetsuro;
(Numazu-shi, JP) ; Honda; Takkaki; (Numazu-shi,
JP) ; Saito; Hideo; (Mishima-shi, JP) ;
Yasuda; Satoshi; (Kawasaki-shi, JP) ; Takekuma;
Hideki; (Numazu-shi, JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Family ID: |
36204924 |
Appl. No.: |
11/256079 |
Filed: |
October 24, 2005 |
Current U.S.
Class: |
62/185 |
Current CPC
Class: |
F25B 2321/0212 20130101;
F25B 2321/0252 20130101; F25D 17/02 20130101; F25B 21/02
20130101 |
Class at
Publication: |
062/185 |
International
Class: |
F25D 17/02 20060101
F25D017/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 25, 2004 |
JP |
2004-309705 |
Oct 14, 2005 |
JP |
2005-299606 |
Claims
1. A constant-temperature fluid supply system comprising: a first
constant-temperature fluid supply apparatus having an input side to
which a cooling fluid not controlled in temperature is supplied,
and an output side from which a first constant-temperature fluid
having a stable temperature is supplied; and a second
constant-temperature fluid supply apparatus having an input side to
which the first constant-temperature fluid is supplied, and an
output side from which a second constant-temperature fluid having a
more stable temperature than that of the first constant-temperature
fluid is supplied.
2. The constant-temperature fluid supply system according to claim
1, wherein the first constant-temperature fluid supply apparatus
comprises a cooling mechanism including an evaporator and a
condenser, the cooling fluid and the first constant-temperature
fluid exchange heat, the input side of the first
constant-temperature fluid is a heat-waste side where a passage of
the cooling fluid is formed, and the output side of the first
constant-temperature fluid is a cooling side where a passage of the
first constant-temperature fluid is formed.
3. The constant-temperature fluid supply system according to claim
1, wherein the second constant-temperature fluid supply apparatus
includes a Peltier element having input and output sides, the input
side of the Peltier element is a heat-waste side where a passage of
the first constant-temperature fluid is formed, and the output side
of the Peltier element is a heat-absorbent side where a passage of
the second constant-temperature fluid is formed.
4. The constant-temperature fluid supply system according to claim
3, wherein the second constant-temperature fluid supply apparatus
further includes at least one Peltier element in addition to said
Peltier element, and the second constant-temperature fluid supply
apparatus supplies second constant-temperature fluids of different
temperatures.
5. The constant-temperature fluid supply system according to claim
1, wherein the first constant-temperature fluid is controlled such
that the temperature thereof is .+-.0.1.degree. C. of a setting
temperature, and the second constant-temperature fluid is
controlled such that the temperature thereof is .+-.0.01.degree. C.
of a setting temperature.
6. The constant-temperature fluid supply system according to claim
1, wherein the second constant-temperature fluid is supplied to an
object whose temperature is to be controlled, and a passage between
the second constant-temperature fluid supply apparatus and the
object is thermally insulated by a heat insulator.
7. A constant-temperature fluid supply system configured to keep a
first portion and a second portion of an object at predetermined
temperatures, said constant-temperature fluid supply system
comprising: a first constant-temperature fluid supply apparatus
having an input side to which a cooling fluid not controlled in
temperature is supplied, and an output side from which a first
constant-temperature fluid having a stable temperature is supplied,
part of the first constant-temperature fluid being supplied to the
first portion of the object; and a second constant-temperature
fluid supply apparatus having an input side to which remaining part
of the first constant-temperature fluid is supplied, and an output
side from which a second constant-temperature fluid having a more
stable temperature than that of the first constant-temperature
fluid is supplied.
8. The constant-temperature fluid supply system according to claim
7, wherein the first constant-temperature fluid supply apparatus
comprises a cooling mechanism including an evaporator and a
condenser, the cooling fluid and the first constant-temperature
fluid exchange heat, the input side of the first
constant-temperature fluid is a heat-waste side where a passage of
the cooling fluid is formed, and the output side of the first
constant-temperature fluid is a cooling side where a passage of the
first constant-temperature fluid is formed.
9. The constant-temperature fluid supply system according to claim
7, wherein the second constant-temperature fluid supply apparatus
includes a Peltier element having input and output sides, the input
side of the Peltier element is a heat-waste side where a passage of
the first constant-temperature fluid is formed, and the output side
of the Peltier element is a heat-absorbent side where a passage of
the second constant-temperature fluid is formed.
10. The constant-temperature fluid supply system according to claim
9, wherein the second constant-temperature fluid supply apparatus
further includes at least one Peltier element in addition to said
Peltier element, and the second constant-temperature fluid supply
apparatus supplies second constant-temperature fluids of different
temperatures.
11. The constant-temperature fluid supply system according to claim
7, wherein the first constant-temperature fluid is controlled such
that the temperature thereof is .+-.0.1.degree. C. of a setting
temperature, and the second constant-temperature fluid is
controlled such that the temperature thereof is .+-.0.01.degree. C.
of a setting temperature.
12. The constant-temperature fluid supply system according to claim
7, wherein a passage between the second constant-temperature fluid
supply apparatus and the object is thermally insulated by a heat
insulator.
13. A constant-temperature fluid supply system configured to keep a
first portion and a second portion of an object at predetermined
temperatures, said constant-temperature fluid supply system
comprising: a first constant-temperature fluid supply apparatus
having an input side to which a cooling fluid not controlled in
temperature is supplied, and an output side from which a first
constant-temperature fluid having a stable temperature is supplied;
and a second constant-temperature fluid supply apparatus having an
input side to which the first constant-temperature fluid is
supplied, and an output side from which a second
constant-temperature fluid having a more stable temperature than
that of the first constant-temperature fluid is supplied. a third
constant-temperature fluid supply apparatus having an input side to
which the first constant-temperature fluid is supplied, and an
output side from which a third constant-temperature fluid having a
more stable temperature than that of the first constant-temperature
fluid is supplied to the second portion of the object.
14. The constant-temperature fluid supply system according to claim
13, wherein the second constant-temperature fluid supplied from the
second fluid constant-temperature fluid supply apparatus and the
third constant-temperature fluid supplied from the third
constant-temperature fluid supply apparatus are set at different
temperatures.
15. The constant-temperature fluid supply system according to claim
13, wherein the first constant-temperature fluid supply apparatus
comprises a cooling mechanism including an evaporator and a
condenser, the cooling fluid and the first constant-temperature
fluid exchange heat, the input side of the first
constant-temperature fluid is a heat-waste side where a passage of
the cooling fluid is formed, and the output side of the first
constant-temperature fluid is a cooling side where a passage of the
first constant-temperature fluid is formed.
16. The constant-temperature fluid supply system according to claim
13, wherein each of the second and third constant-temperature fluid
supply apparatuses includes a Peltier element having input and
output sides, the input side of the Peltier element is a heat-waste
side where a passage of the first constant-temperature fluid is
formed, and the output side of the Peltier element is a
heat-absorbent side where a passage of the second
constant-temperature fluid is formed.
17. The constant-temperature fluid supply system according to claim
13, wherein the first constant-temperature fluid is controlled such
that the temperature thereof is .+-.0.1.degree. C. of a setting
temperature, and the second and third constant-temperature fluids
are controlled such that the temperatures thereof are
.+-.0.01.degree. C. of setting temperatures.
18. The constant-temperature fluid supply system according to claim
13, wherein a passage between the second constant-temperature fluid
supply apparatus and the object and a passage between the third
constant-temperature fluid supply apparatus and the object are
thermally insulated by a heat insulator.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from prior Japanese Patent Applications No. 2004-309705,
filed Oct. 25, 2004; and No. 2005-299606, filed Oct. 14, 2005 the
entire contents of both of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a constant-temperature
fluid supply system adapted for use in a semiconductor
manufacturing apparatus and configured to control the temperature
of a target device with a high degree of accuracy.
[0004] 2. Description of the Related Art
[0005] Devices that have to be kept at constant temperatures are
provided with an internal fluid passage for constant-temperature
water. By circulation of the constant-temperature water supplied
from constant-temperature fluid supply sources, the devices can be
kept in the constant-temperature state. In other words, the
temperatures of the devices can be kept at a stable value by
maintaining the thermal equilibrium between the devices and the
constant-temperature water. As can be seen from this, in order to
stabilize the temperatures of the devices with a high degree of
accuracy, it is necessary to control the temperature of the
constant-temperature water with a high degree of accuracy (Jpn. UM
Appln. KOKAI Publication No 5-25190).
[0006] To control the temperature of the constant-temperature water
with a high degree of accuracy, it is necessary to suppress the
heat acting as external disturbances. Among the external
disturbances, temperature variations of cooling water are a factor
that may vary the temperature of the constant-temperature water.
Normally, the water provided by the municipal water department
(hereinafter referred to as tap water for the sake of simplicity)
and the circulation water in plants are used as the cooling water.
Those kinds of water are not controlled in temperature, and their
temperatures inevitably vary. Due to the temperature variations of
the cooling water, the constant-temperature water may also vary in
temperature even if the setting temperature is constant.
[0007] This problem is marked in the case of the cooling water for
use in a chiller unit. The tap water and the circulation water in
plants are very likely vary in temperature due to changes in the
ambient temperature. In some cases, they may undergo a temperature
variation of about 10.degree. C. in a day. Since this results in a
change in the temperature of the constant-temperature water, the
target devices cannot be controlled with a high degree of
accuracy.
[0008] As discussed above, the conventional constant-temperature
fluid supply apparatus has problems in that the temperature of the
constant-temperature fluid varies due to temperature variations of
the externally-provided cooling water.
BRIEF SUMMARY OF THE INVENTION
[0009] According to one aspect of the present invention, there is
provided a constant-temperature fluid supply system comprising:
[0010] a first constant-temperature fluid supply apparatus having
an input side to which a cooling fluid not controlled in
temperature is supplied, and an output side from which a first
constant-temperature fluid having a stable temperature is supplied;
and
[0011] a second constant-temperature fluid supply apparatus having
an input side to which the first constant-temperature fluid is
supplied, and an output side from which a second
constant-temperature fluid having a more stable temperature than
that of the first constant-temperature fluid is supplied.
[0012] According to another aspect of the present invention, there
is provided a constant-temperature fluid supply system configured
to keep a first portion and a second portion of an object at
predetermined temperatures, the constant-temperature fluid supply
system comprising:
[0013] a first constant-temperature fluid supply apparatus having
an input side to which a cooling fluid not controlled in
temperature is supplied, and an output side from which a first
constant-temperature fluid having a stable temperature is supplied,
part of the first constant-temperature fluid being supplied to the
first portion of the object; and
[0014] a second constant-temperature fluid supply apparatus having
an input side to which remaining part of the first
constant-temperature fluid is supplied, and an output side from
which a second constant-temperature fluid having a more stable
temperature than that of the first constant-temperature fluid is
supplied.
[0015] According to still another aspect of the present invention,
there is provided a constant-temperature fluid supply system
configured to keep a first portion and a second portion of an
object at predetermined temperatures, the constant-temperature
fluid supply system comprising:
[0016] a first constant-temperature fluid supply apparatus having
an input side to which a cooling fluid not controlled in
temperature is supplied, and an output side from which a first
constant-temperature fluid having a stable temperature is supplied;
and
[0017] a second constant-temperature fluid supply apparatus having
an input side to which the first constant-temperature fluid is
supplied, and an output side from which a second
constant-temperature fluid having a more stable temperature than
that of the first constant-temperature fluid is supplied.
[0018] a third constant-temperature fluid supply apparatus having
an input side to which the first constant-temperature fluid is
supplied, and an output side from which a third
constant-temperature fluid having a more stable temperature than
that of the first constant-temperature fluid is supplied to the
second portion of the object.
[0019] Additional objects and advantages of the invention will be
set forth in the description which follows, and in part will be
obvious from the description, or may be learned by practice of the
invention. The objects and advantages of the invention may be
realized and obtained by means of the instrumentalities and
combinations particularly pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0020] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate embodiments of
the invention, and together with the general description given
above and the detailed description of the embodiments given below,
serve to explain the principles of the invention.
[0021] FIG. 1 is a schematic diagram showing a constant-temperature
fluid supply system according to the first embodiment.
[0022] FIG. 2 shows a specific structure of the first
constant-temperature fluid supply apparatus employed in the
constant-temperature fluid supply system of the first
embodiment.
[0023] FIG. 3 shows a specific structure of the second
constant-temperature fluid supply apparatus employed in the
constant-temperature fluid supply system of the first
embodiment.
[0024] FIG. 4 shows another specific structure of the first
constant-temperature fluid supply apparatus employed in the
constant-temperature fluid supply system of the first
embodiment.
[0025] FIG. 5 is a schematic diagram showing a constant-temperature
fluid supply system according to the second embodiment.
[0026] FIG. 6 is a schematic diagram showing a constant-temperature
fluid supply system according to the third embodiment.
[0027] FIG. 7 shows an example of an object whose temperature is to
be kept constant by the constant-temperature fluid supply systems
of the second and third embodiments.
[0028] FIG. 8 is a schematic diagram showing a constant-temperature
fluid supply system according to the fourth embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The present invention will now be described in detail,
referring to the embodiments shown in the accompanying
drawings.
First Embodiment
[0030] In FIG. 1, reference numeral 10 denotes a first
constant-temperature fluid supply apparatus. Cooling water 101
(i.e., cooling fluid), which is tap water or circulation water in
plants, is supplied to the input side of the apparatus 10. First
constant-temperature water 102 (i.e., a first constant-temperature
fluid) is output from the output side of the apparatus 10.
Reference numeral 20 denotes a second constant-temperature fluid
supply apparatus. First constant-temperature water 102 is supplied
to the input side of the apparatus 20 as cooling water. Second
constant-temperature water 103 (i.e., a second constant-temperature
fluid) is output from the output side of the apparatus 20. The
second constant-temperature water 103 is supplied to an external
apparatus 30 (i.e., an apparatus whose temperature is to be kept
constant), for maintaining its constant temperature.
[0031] The first and second constant-temperature fluid supply
apparatuses 10 and 20 are connected together by means of a flexible
connection hose and can be separated, if necessary. The second
constant-temperature fluid supply apparatuses 20 and the external
apparatus 30 are connected together by means of a flexible
connection hose and can be separated, if necessary. The first
constant-temperature water 102 circulates between the first and
second constant-temperature fluid supply apparatuses 10 and 20. The
second constant-temperature water 103 circulates between the second
constant-temperature fluid supply apparatus 20 and the external
apparatus 30.
[0032] The passage for the second constant-temperature water 103,
i.e., the hose between the second constant-temperature fluid supply
apparatus 20 and the external apparatus 30, is covered with a heat
insulating material to prevent external thermal effects. The
external apparatus 30 is installed in a temperature-controlled
room.
[0033] As shown in FIG. 2, the first constant-temperature fluid
supply apparatus 10 is provided with an evaporator and a condenser
and utilizes heat exchange for maintaining a constant temperature.
The constant-fluid supply apparatus 10 comprises a condenser 11, an
evaporator 12, a compressor 13, an electromagnetic valve 15, a
thermometer 16, a controller 17 and a pump 18.
[0034] The cooling water 101 supplied to the constant-temperature
fluid supply apparatus 10 is used for cooling the condenser 11.
After being cooled and adjusted in temperature by the evaporator
12, the constant-temperature water 102 is supplied to the
constant-temperature fluid supply apparatus 20. The thermometer 16
is in the constant-temperature water passage and located on the
output side of the evaporator 12. The setting temperature of the
constant-temperature water 102 is entered to the controller 17, and
a detection temperature which the thermometer 16 detects with
respect to the constant-temperature water 102 is also supplied to
the controller 17. Based on the difference between the setting
temperature and the detection temperature, the controller 17
controls the openings of electromagnetic valves 14 and 15, thereby
controlling the output of the evaporator 12. In this manner, the
constant-temperature water 102 is kept at the setting
temperature.
[0035] As shown in FIG. 3, the second constant-temperature fluid
supply apparatus 20 employs a Peltier element 21 for maintaining
the constant temperature with a high degree of accuracy. A passage
22 for permitting constant-temperature water 102 to flow is
connected to the heat-waste side (input side) of the Peltier
element 21, and a passage 23 for permitting constant-temperature
water 103 to flow is connected to the heat-absorbent side (output
side) of the Peltier element 21. With this structure, the Peltier
element 21 is cooled by the constant-temperature water 102 having a
comparatively stable temperature, and the Peltier element 21 cools
the constant-temperature water 103 so that the water 103 has a very
stable temperature.
[0036] Although not illustrated, the temperature of the water 102
on the heat-waste side of the Peltier element 21 is stable, and the
water 103 on the heat-absorbent side can be kept constant by
controlling the current supply. For strict control of the
constancy, a temperature sensor 24 may be provided in the passage
23 at a position downstream of the Peltier element 21. In this
case, the output of the temperature sensor 24 is fed back to the
power supply 25 of the Peltier element 21, and the current supply
to the Peltier element 21 is controlled in accordance with the
temperature detected by the temperature sensor 24.
[0037] In addition to the temperature sensor 24 described above,
another temperature sensor may be provided at the position where
the external apparatus under temperature control is located. In
accordance with the temperatures detected by these two temperature
sensors, the current supply to the Peltier element 21 may be
controlled.
[0038] In the first embodiment, the first constant-temperature
fluid supply apparatus 10 uses is either tap water or circulation
water in plants as the cooling water 101. Since this type of water
undergoes a temperature variation of about 10.degree. C., the
temperature variation of water 102 may not be reduced to be less
than 1/10.degree. C. but can be 1/10.degree. C. Since the first
constant-temperature fluid supply apparatus 10 keeps the
temperature of water 102 constant to a certain extent (to be less
than 1/10.degree. C.), and the water 102 whose temperature is
controlled in this manner is used as the cooling water of the
second constant-temperature fluid supply apparatus 20. Hence, the
temperature of water 103 can be kept constant in a fully
satisfactory manner. As a result, the temperature variation of
water 103 can be reduced to be less than 1/100.degree. C.
[0039] In the case where the processing capacity of the first
constant-temperature fluid supply apparatus 10 was set at 400 W and
5 l/min, water 102 could be controlled to be 25.degree.
C.+-.0.1.degree. C. In addition to this, where the processing
capacity of the second constant-temperature fluid supply apparatus
20 was set at 100 W and 5 l/min, water 103 could be controlled to
be 25.degree. C..+-.0.01.degree. C.
[0040] Even an external apparatus 30 requiring highly accurate
temperature control, such as the vacuum chamber of an electron beam
exposure apparatus, can be stably kept at a constant temperature,
without being adversely affected by the temperature variations of
cooling water 101. In addition to this, since the second
constant-temperature fluid supply apparatus 20 employs the Peltier
element 21, it is small in size and enables very high temperature
constancy. A plurality of Peltier elements 21 may be used. In this
case, different portions of the external apparatus 30 can be
independently controlled to have different temperatures.
[0041] The first and second constant-temperature fluid supply
apparatuses 10 and 20 are connected together by means of a hose,
and if one of them does not operate normally, it is merely replaced
with a new or normally-operating apparatus. The time and cost
required for restoration can be reduced, accordingly. Furthermore,
the first and second constant-temperature fluid supply apparatuses
10 and 20 may be apparatuses having the same function.
[0042] The first constant-temperature fluid supply apparatus 10 may
use an ordinary type of heat exchange, as shown in FIG. 4. In FIG.
4, reference numeral 43 denotes a heat exchanger, reference numeral
46 denotes a thermometer, reference numeral 47 denotes a
controller, and reference numeral 48 denotes a pump. In the case of
the apparatus shown in FIG. 4, the controller 47 controls the flow
rate of cooling water 101 in accordance with the temperature the
thermometer 46 measures, and the temperature of water 102 can be
controlled, accordingly.
Second Embodiment
[0043] FIG. 5 is a schematic diagram showing a constant-temperature
fluid supply system according to the second embodiment. In FIG. 5,
similar or corresponding structural elements are denoted by the
same reference numerals as used in FIG. 1, and a detailed
description of such structural elements will be omitted herein.
[0044] The second embodiment differs from the first embodiment in
that the first constant-temperature water 102 from the first
constant-temperature fluid supply apparatus 10 is supplied to not
only to the second constant-temperature fluid supply apparatus 20
but also to an external apparatus 301. In other words, part of the
first constant-temperature water 102 is circulated between the
first fluid supply apparatus 10 and the external apparatus 301.
With this structure, the temperature of external apparatus 301 can
be kept at a constant value to a certain extent (the temperature of
external apparatus 301 cannot be so accurately controlled as the
temperature of external apparatus 30).
[0045] It is comparatively easy to improve the cooling performance
of the first constant-temperature fluid supply apparatus 10. This
is why the passage of the constant-temperature water 102 can be
branched into sections connected to different apparatuses, without
causing any problems. External apparatuses 30 and 301 may be
different positions of the same electron beam drawing apparatus.
For example, external apparatus 30 may be a sample chamber or an
electronic lens barrel. External apparatus 301 is, for example, an
apparatus portion that generates much heat but does not require
highly-controlled temperature accuracy.
Third Embodiment
[0046] FIG. 6 is a schematic diagram showing a constant-temperature
fluid supply system according to the third embodiment. In FIG. 6,
similar or corresponding structural elements are denoted by the
same reference numerals as used in FIG. 1, and a detailed
description of such structural elements will be omitted herein.
[0047] The third embodiment differs from the first embodiment in
that second constant-temperature fluid supply apparatuses 201 and
202 are provided in addition to the second constant-temperature
fluid supply apparatus 20. In other words, three second
constant-temperature fluid supply apparatuses 20, 201 and 202 are
employed to keep the temperatures of external apparatuses 30, 301
and 302 at constant values.
[0048] In the third embodiment, the first constant-temperature
water 102 is supplied to three apparatuses, namely
constant-temperature fluid supply apparatus 20,
constant-temperature fluid supply apparatus 201 and
constant-temperature fluid supply apparatus 202. As in the first
embodiment, each of the constant-temperature fluid supply
apparatuses 20, 201 and 202 comprises a Peltier element.
[0049] The second constant-temperature water 103 supplied from the
output side of constant-temperature fluid supply apparatus 20 flows
to external apparatus 30 and keeps this external apparatus at a
constant temperature. The second constant-temperature water 104
supplied from the output side of constant-temperature fluid supply
apparatus 201 flows to external apparatus 301 and keeps this
external apparatus at a constant temperature. The second
constant-temperature water 105 supplied from the output side of
constant-temperature fluid supply apparatus 202 flows to the
external apparatus 302 and keeps this external apparatus at a
constant temperature.
[0050] FIG. 7 is a diagram schematically showing an electron beam
exposure apparatus whose temperature is to be kept constant. In
FIG. 7, reference numeral 71 denotes a sample chamber, reference
numeral 72 denotes an electronic lens barrel, reference numeral 73
denotes a Z sensor configured to detect the height level of the
sample surface, reference numeral 74 denotes a deflection amplifier
used for driving a deflector provided inside the electronic lens
barrel, and reference numeral 75 denotes an external power supply.
By using the constant-temperature fluid supply system shown in FIG.
5 or 6, the temperatures at portions of the electron beam exposure
apparatus can be controlled independently of one another.
[0051] For example, the constant-temperature water 103 which the
constant-temperature fluid supply apparatus 20 supplies to the
sample chamber 71 is controlled at 25.degree. C..+-.0.01.degree. C.
The constant-temperature water 104 which the constant-temperature
fluid supply apparatus 201 supplies to the electronic lens barrel
72 and Z sensor 73 is controlled at 24.degree. C..+-.0.01.degree.
C. The constant-temperature water 105 which the
constant-temperature fluid supply apparatus 202 supplies to the
deflection amplifier 74 is controlled to be in the range of
20.degree. C. to 30.degree. C..+-.0.01.degree. C. The
constant-temperature water 102 which the first constant-temperature
fluid supply apparatus 10 supplies to the power supply 75 is
controlled to be in the range of 20.degree. C. to 30.degree.
C..+-.0.1.degree. C.
[0052] The constant-temperature fluid supplied to the electronic
lens barrel 72 and Z sensor 73 is set at a temperature slightly
lower than that of the constant-temperature fluid supplied to the
sample chamber 71, because the electronic lens barrel 72 and Z
sensor 73 have a heat generating section. The temperature of the
differential amplifier 74 has to be controlled with high accuracy,
but the temperature itself need not limited to a specific value.
The temperature of the external power supply 75 need not be
controlled with high accuracy. Since the external power supply 75
merely needs to be cooled to some extent, the supply of water 102
is sufficient.
[0053] As described above, a plurality of constant-temperature
fluid supply apparatuses are selectively used to control the
temperatures of portions of an object in accordance with the heat
the object portions may generate and the temperature control range
the object portions may require. The use of a plurality of
constant-temperature fluid supply apparatuses enables efficient
temperature control.
Fourth Embodiment
[0054] FIG. 8 is a schematic diagram showing a constant-temperature
fluid supply system according to the fourth embodiment. In FIG. 8,
similar or corresponding structural elements are denoted by the
same reference numerals as used in FIG. 1, and a detailed
description of such structural elements will be omitted herein.
[0055] The fourth embodiment differs from the first embodiment in
that the first constant-temperature fluid supply apparatus 10 and
the second constant-temperature fluid supply apparatus 20 are
connected directly to each other and are integrally assembled
together. To be more specific, the first and second
constant-temperature fluid supply apparatuses are fixed to the same
base 50, and the output side of fluid supply apparatus 10 and the
input side of fluid supply apparatus 20 are coupled together.
[0056] With this structure, the fourth embodiment produces similar
advantages to those of the first embodiment. In addition to this,
the entire system can be small in size because the first and second
constant-temperature fluid supply apparatuses 10 and 20 are
integrally assembled as one body.
Modification
[0057] The present invention is not limited to the embodiments
described above. In the embodiments described above, the first
constant-temperature fluid supply apparatus is provided with either
(i) a cooling mechanism including the evaporator and condenser
shown in FIG. 2, or (ii) a cooling mechanism including the heat
exchanger shown in FIG. 4. The present invention is not limited to
these configurations and may be varied as needed. The first
constant-temperature fluid supply apparatus does not require such
high precision as needed by the second constant-temperature fluid
supply apparatus, so that the former apparatus is preferably made
of a low-cost apparatus. The second constant-temperature fluid
supply apparatus employs a Peltier element, but may be of any type
as long as highly accurate control is ensured.
[0058] The constant-temperature fluid is not limited to water but
may be another kind of liquid. In addition, the cooling water used
with the first constant-temperature fluid supply apparatus may be
replaced with a gas. To be more specific, the heat-waste side of
the first constant-temperature fluid supply apparatus may be cooled
by the air by providing a cooling fan.
[0059] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
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