U.S. patent application number 12/236014 was filed with the patent office on 2009-01-15 for heat treatment apparatus.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Tae-gyu Kim, Bang-Weon Lee, Dong-Woo Lee, Jin-Sung Lee, Tae-Sang Park.
Application Number | 20090013698 12/236014 |
Document ID | / |
Family ID | 35480126 |
Filed Date | 2009-01-15 |
United States Patent
Application |
20090013698 |
Kind Code |
A1 |
Kim; Tae-gyu ; et
al. |
January 15, 2009 |
HEAT TREATMENT APPARATUS
Abstract
Provided is a heat treatment apparatus. The heat treatment
apparatus includes a heating plate including a heater; a chamber
case including a cooling chamber, and coupled to a lower portion of
the heating plate; and at least one atomizing unit installed on the
chamber case to generate liquid droplet aerosol by mixing a cooling
liquid and a gas, and at the same time, to inject the liquid
droplet aerosol into the cooling chamber.
Inventors: |
Kim; Tae-gyu; (Hwaseong-gun,
KR) ; Lee; Dong-Woo; (Seoul, KR) ; Lee;
Jin-Sung; (Seoul, KR) ; Park; Tae-Sang;
(Suwon-si, KR) ; Lee; Bang-Weon; (Seoul,
KR) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W., SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
Samsung Electronics Co.,
Ltd.
Suwon-si
KR
|
Family ID: |
35480126 |
Appl. No.: |
12/236014 |
Filed: |
September 23, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11058279 |
Feb 16, 2005 |
7448604 |
|
|
12236014 |
|
|
|
|
Current U.S.
Class: |
62/64 |
Current CPC
Class: |
H01L 21/67109 20130101;
B05B 7/0441 20130101 |
Class at
Publication: |
62/64 |
International
Class: |
F25D 31/00 20060101
F25D031/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 19, 2004 |
KR |
2004-45856 |
Claims
1. A cooling method of a heat treatment apparatus, which includes a
cooling chamber under a heating plate and cools down the heating
plate by injecting liquid droplet aerosol that is formed by mixing
a cooling liquid and a gas into the cooling chamber, the method
comprising: cooling the heating plate by continuously injecting the
liquid droplet aerosol into the cooling chamber for a predetermined
period; and removing vapor remaining in the cooling chamber by
injecting only the gas into the cooling chamber.
2. The method of claim 1, wherein the gas is dry air.
3. A cooling method of a heat treatment apparatus, which includes a
cooling chamber under a heating plate and cools down the heating
plate by injecting liquid droplet aerosol that is formed by mixing
a cooling liquid and a gas into the cooling chamber, the method
comprising: cooling the heating plate by injecting the liquid
droplet aerosol in a pulse form into the cooling chamber for a
predetermined period; and removing vapor remaining in the cooling
chamber by injecting only the gas into the cooling chamber.
4. The method of claim 3, wherein the injecting of the liquid
droplet aerosol in a pulse form includes supplying the cooling
liquid in a pulse form and supplying the gas continuously into the
cooling chamber for a predetermined period.
5. The method of claim 3, wherein the gas is dry air.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This is a divisional application of U.S. application Ser.
No. 11/058,279 filed on Feb. 16, 2005, the entire contents of which
are incorporated herein by reference. This application claims the
priority of Korean Patent Application No. 2004-45856, filed on Jun.
19, 2004, in the Korean Intellectual Property Office, the
disclosure of which is incorporated herein in its entirety by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a heat treatment apparatus,
and more particularly, a heat treatment apparatus including a
cooling unit for cooling a heated substrate after heating the
substrate in a photolithography process for manufacturing
semiconductors.
[0004] 2. Description of the Related Art
[0005] In a photolithography process for manufacturing a
semiconductor, a heating process such as a pre-bake process, which
heats a photoresist after applying the photoresist on a wafer, and
a post-exposure bake process, which heats the photoresist after
exposing the photoresist to be a predetermined pattern.
[0006] Recently, semiconductors are mass produced with multiple
kinds, thus wafer heat treatment temperatures can be different
according to the kinds of semiconductors. Therefore, for example,
in a case where the wafer is heated at a temperature of 150.degree.
C. and next process should be performed at a temperature of
100.degree. C., the wafer should be cooled down to the temperature
100.degree. C. as soon as possible in order to improve the
productivity.
[0007] Conventionally, in order to cool down a heating plate after
heating the wafer using the heating plate, the heating plate is
placed in the atmosphere, however, it takes a long time to reach
the set temperature due to a low cooling performance.
[0008] FIG. 1 shows a conventional heat treatment apparatus
including a cooling unit for cooling down a heating plate.
Referring to FIG. 1, a case 66 forming a cooling chamber is
disposed on a lower portion of the heating plate 70. Here, the
wafer W is placed on an upper surface of the heating plate 70, and
a heater 71 for heating the wafer W is disposed on a lower surface
of the heating plate 70. In the cooling chamber, nozzles 74, which
cool down the heating plate 70 heated by the heater 71 by injecting
cooling gas that is induced through a ventilation hole 72 of the
case 66 into the cooling chamber, are installed.
[0009] However, according to the conventional heat treatment
apparatus, the heating plate 70 is forcedly cooled down by the
cooling gas, thus the cooling performance increases higher than the
heat treatment apparatus using a natural cooling method, however,
there is a limit to perform the cooling operation more efficiently.
In addition, since the cooling gas directly contacts the heater,
humidity of the cooling gas should be removed in order to prevent
the electricity from leaking.
SUMMARY OF THE INVENTION
[0010] The present invention provides a heat treatment apparatus
having superior cooling performance and a simple structure, by
injecting mist aerosol in a cooling chamber and cooling a heating
plate using evaporation of the mist aerosol.
[0011] According to an aspect of the present invention, there is
provided a heat treatment apparatus including: a heating plate
including a heater; a chamber case including a cooling chamber, and
coupled to a lower portion of the heating plate; and at least one
atomizing unit installed on the chamber case to generate liquid
droplet aerosol by mixing a cooling liquid and a gas, and at the
same time, to inject the liquid droplet aerosol into the cooling
chamber, wherein the heating plate is cooled down by evaporating
the liquid droplet aerosol injected in the cooling chamber.
[0012] The atomizing unit may be installed so that a portion,
through which the liquid aerosol is injected, can protrude into the
cooling chamber.
[0013] The atomizing unit may include a first nozzle for injecting
the cooling liquid and a second nozzle for injecting the gas, and
the first nozzle is installed in the second nozzle.
[0014] At least one discharge hole, through which vapor generated
by the evaporation of the liquid droplet aerosol is discharged, may
be formed on the chamber case.
[0015] The atomizing unit may include a diffusion member that
diffuses the injected liquid droplet aerosol.
[0016] The cooling liquid may include water, and the gas may
include air.
[0017] A lower surface of the heating plate may be processed so as
to increase a surface area, to which the liquid droplet aerosol
contacts. Here, a capillary structure may be formed on the lower
surface of the heating plate by a sintering process, or a plurality
of grooves may be formed on the lower surface of the heating
plate.
[0018] According to another aspect of the present invention, there
is provided a heat treatment apparatus including: a heating plate
including an upper plate, on which a substrate is mounted, a lower
plate placed under the upper plate, and a heater placed between the
upper plate and the lower plate to heat the substrate; a chamber
case including a cooling chamber and coupled to a lower portion of
the lower plate; and at least one atomizing unit installed on the
chamber case to generate liquid droplet aerosol by mixing a cooling
liquid and a gas, and at the same time, to inject the liquid
droplet aerosol into the cooling chamber, wherein the heating plate
is cooled down by evaporating the liquid droplet aerosol injected
in the cooling chamber.
[0019] The atomizing unit may include a first nozzle for injecting
the cooling liquid and a second nozzle for injecting the gas. The
first and second nozzles may be connected to a first supplying tube
that supplies the cooling liquid and a second supplying tube that
supplies the gas, respectively. In addition, the first and second
supplying tubes may include a first flow control device and a
second flow control device for controlling flow amount of the
liquid and the gas, respectively.
[0020] A lower surface of the heating plate may be processed so as
to increase a surface area, to which the liquid droplet aerosol
contacts. Here, a capillary structure may be formed on the lower
surface of the heating plate by a sintering process, or a plurality
of grooves may be formed on the lower surface of the heating
plate.
[0021] The upper and lower plates may be formed of a metal, a
ceramic, a glass, or a thermal-resistant resin.
[0022] A gasket may be disposed on a portion where the lower plate
and the chamber case are coupled to each other.
[0023] According to still another aspect of the present invention,
there is provided a cooling method of a heat treatment apparatus,
which includes a cooling chamber under a heating plate and cools
down the heating plate by injecting liquid droplet aerosol that is
formed by mixing a cooling liquid and a gas into the cooling
chamber, the method including: cooling the heating plate by
continuously injecting the liquid droplet aerosol into the cooling
chamber for a predetermined period; and removing vapor remaining in
the cooling chamber by injecting only the gas into the cooling
chamber.
[0024] The gas may be dry air.
[0025] According to yet still another aspect of the present
invention, there is provided a cooling method of a heat treatment
apparatus, which includes a cooling chamber under a heating plate
and cools down the heating plate by injecting liquid droplet
aerosol that is formed by mixing a cooling liquid and a gas into
the cooling chamber, the method including: cooling the heating
plate by injecting the liquid droplet aerosol in a pulse form into
the cooling chamber for a predetermined period; and removing vapor
remaining in the cooling chamber by injecting only the gas into the
cooling chamber.
[0026] The injecting of the liquid droplet aerosol in a pulse form
may include supplying the cooling liquid in a pulse form and
supplying the gas continuously into the cooling chamber for a
predetermined period.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and other features and advantages of the present
invention will become more apparent by describing in detail
exemplary embodiments thereof with reference to the attached
drawings in which:
[0028] FIG. 1 is a view showing a conventional heat treatment
apparatus;
[0029] FIG. 2 is a cut perspective view showing a heat treatment
apparatus according to an exemplary embodiment of the present
invention;
[0030] FIG. 3 is a schematic cross-sectional view showing a heat
treatment apparatus according to an exemplary embodiment of the
present invention;
[0031] FIG. 4 is a cross-sectional view of the nozzle shown in FIG.
3;
[0032] FIG. 5A is a view showing a state where a capillary
structure is formed by sintering on a lower surface of a lower
plate in the heat treatment apparatus according to an exemplary
embodiment of the present invention;
[0033] FIG. 5B is a view showing a state where a plurality of
grooves are formed on the lower surface of the lower plate by
processing in the heat treatment apparatus according to an
exemplary embodiment of the present invention;
[0034] FIG. 6A is a view illustrating a cooling method of the heat
treatment apparatus according to an exemplary embodiment of the
present invention; and
[0035] FIG. 6B is a view showing a cooling method of the heat
treatment apparatus according to another exemplary embodiment of
the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] Exemplary embodiments of the invention will now be described
below by reference to the attached Figures. The described exemplary
embodiments are intended to assist the understanding of the
invention, and are not intended to limit the scope of the invention
in any way.
[0037] FIG. 2 is a cut perspective view showing a heat treatment
apparatus according to an exemplary embodiment of the present
invention, and FIG. 3 is a schematic cross-sectional view showing
the heat treatment apparatus shown in FIG. 2.
[0038] Referring to FIGS. 2 and 3, the heat treatment apparatus
according to an exemplary embodiment of the present invention
includes a heating plate 100, a chamber case 110 coupled to a lower
portion of the heat plate 100, and at least one atomizing unit 120
installed on the chamber case 110.
[0039] The heating plate 100 includes an upper plate 105 and a
lower plate 101, and a heater 103 disposed between the upper plate
105 and the lower plate 101. On the upper plate 105, a substrate,
for example, a wafer W is disposed. In addition, the lower plate
101 becomes an upper wall of a cooling chamber 150, which will be
described later. Here, the upper and lower plates 105 and 101 can
be formed of a metal, a ceramic having high thermal conductivity, a
glass, or a thermal-resistant resin. The heater 103 heats the wafer
W disposed on the upper plate 105 to a predetermined temperature by
applied electric current, and is formed of a heating resistant
material.
[0040] The chamber case 110 is coupled to the lower portion of the
lower plate 101 to form a cooling chamber 150 for cooling down the
heating plate 100 that is heated by the heater 103 to a
predetermined temperature. On the other hand, a gasket 107 for
sealing the cooling chamber 150 is disposed on the coupled portion
of the lower plate 101 and the chamber case 110.
[0041] The atomizing units 120 are installed on a lower wall of the
chamber case 110 to generate liquid droplet aerosol of fine size by
mixing cooling liquid and gas, and to inject the liquid droplet
aerosol into the cooling chamber 150. Thus, the atomizing unit 120
is installed so that a portion through which the liquid droplet
aerosol is injected protrudes inwardly in the cooling chamber 150.
Here, the cooling liquid can be the water, and the gas can be the
air.
[0042] The liquid droplet aerosol injected into the cooling chamber
150 cools down the heating plate 100 by being evaporated. In more
detail, the liquid droplet aerosol injected into the cooling
chamber 150 is attached on the lower surface of the lower plate
101, and the liquid droplet aerosol attached on the lower surface
of the lower plate 101 takes the heat from the lower plate 101 and
evaporates to cool down the heating plate 100.
[0043] The heat capacity required to completely vaporize the liquid
of 1 g at a constant temperature is called the evaporation heat,
and the evaporation heat of the water is 2270 J/g. Therefore, the
heat capacity required to vaporize 1 g of water is 540 times more
than the heat capacity 4.2 J that is required to raise the
temperature of 1 g of water by 1.degree. C. Thus, the cooling of
the heat plate 100 using the evaporation of the cooling liquid, for
example, the water as in an exemplary embodiment of the present
invention, is a very effective cooling method.
[0044] At least a discharge hole 115 is formed on a lower wall of
the chamber case 110, the vapor generated by the evaporation of the
liquid droplet aerosol is discharged through the discharge hole
115.
[0045] On the other hand, FIG. 2 shows the two atomizing units 120
installed on the lower wall of the chamber case 110, however, the
present exemplary embodiment is not limited thereto, one or more
than three atomizing units 120 can be installed on the lower wall
of the chamber case 110. Otherwise, the atomizing units 120 can be
installed on a side wall of the chamber case 110. In addition, two
or more discharge holes 115 can be formed on the lower wall or the
side wall of the chamber case 110.
[0046] As described above, when the liquid droplet aerosol is
generated by mixing the cooling liquid and gas, and at the same
time, the generated liquid droplet aerosol is injected directly
into the cooling chamber 150 by the atomizing units 120 installed
on the chamber case 110, the supplied liquid droplet aerosol cools
down the heating plate 100 by changing its phase without being
lost, thus the heat plate 100 can be cooled down to a predetermined
temperature rapidly.
[0047] FIG. 4 is a cross-sectional view showing an expanded view of
the atomizing unit 120 shown in FIG. 3. Referring to FIG. 3, the
atomizing unit 120 includes a first nozzle 122 that injects the
cooling liquid, for example, the water, and a second nozzle 121
that injects the gas, for example, the air. Here, the first nozzle
122 is installed in the second nozzle 121. In the above structure,
when the cooling liquid and gas are injected simultaneously through
the first and second nozzles 122 and 121, the liquid droplet
aerosol is generated, and the generated liquid droplet aerosol is
injected into the cooling chamber 150. In addition, it is desirable
that a diffusion member 128 is installed on a portion where the
liquid droplet aerosol is injected for diffusing the injected
liquid droplet aerosol in the cooling chamber 150 evenly.
[0048] The first nozzle 122 is connected to a first supplying tube
124 that supplies the cooling liquid, and the second nozzle 121 is
connected to a second supplying tube 123 that supplies the gas.
Here, the first and second supplying tubes 124 and 123 respectively
include a first and a second flow control devices 126 and 125 for
controlling flow amount of the cooling liquid and gas.
[0049] FIGS. 5A and 5B are cross-sectional views showing the lower
surface of the lower plate 101. Referring to FIG. 5A, a capillary
structure 101a is formed on the lower surface of the lower plate
101, and the capillary plate 101a is formed by applying a
predetermined powder on the lower surface of the lower plate 101
and sintering the powder. When the capillary structure 101a is
formed on the lower surface of the lower plate 101, the evaporation
of the aerosol is performed while the liquid droplet aerosol is
evenly applied on the entire lower surface of the lower plate 101.
In addition, a surface area, to which the liquid droplet aerosol
contacts, increases, thus cooling the heating plate 100 more
efficiently. Referring to FIG. 5B, a plurality of fine grooves 101b
are formed on the lower surface of the lower plate 101. The grooves
101b can be formed by processing the lower surface of the lower
plate 101. In addition, the grooves 101b distribute the liquid
droplet aerosol evenly on the lower surface of the lower plate 101,
and increase the surface area contacting to the liquid droplet
aerosol.
[0050] In the heat treatment apparatus having the above structure,
when the liquid droplet aerosol is injected into the cooling
chamber 150 by the atomizing units 120, the liquid droplet aerosol
is attached onto the inner wall of the cooling chamber 150
including the lower surface of the lower plate 101. The liquid
droplet aerosol attached on the inner wall of the cooling chamber
150 absorbs the heat of the peripheral portion and evaporates, and
then is discharged through the discharge hole 115 in the vapor
state. Then, the heating plate 100 can be cooled down to the
desired set temperature.
[0051] When the heating plate 100 is cooled down using the phase
change of the liquid droplet aerosol that is injected in the
cooling chamber 150, the cooling can be performed rapidly. For
example, in order to cool down the heating plate 100 from
150.degree. C. to 100.degree. C., it takes about 50 minutes in the
conventional natural cooling method, however, it takes only about
90 seconds using the heat treatment apparatus of an exemplary
embodiment of the present invention when the aerosol is injected in
a rate of 100 ml/min.
[0052] Hereinafter, a cooling method of the heat treatment
apparatus will be described with reference to FIGS. 6A and 6B.
[0053] FIG. 6A is a graph illustrating the cooling method of the
heat treatment apparatus according to an exemplary embodiment of
the present invention. Referring to FIG. 6A, the liquid droplet
aerosol is injected into the cooling chamber 150 continuously by
the atomizing unit (reference numeral 120 in FIG. 2) for a
predetermined time t1. In that process, the cooling water and the
gas are supplied into the cooling chamber 150 through the first and
second nozzles 122 and 121. Accordingly, the heating plate 100 is
cooled down to the desired temperature by the evaporation of the
injected liquid droplet aerosol.
[0054] In addition, after cooling down the heating plate 100, the
gas is only injected into the cooling chamber 150 by the atomizing
unit 120 for a predetermined time. In that process, the gas is only
supplied into the cooling chamber 150 through the second nozzle
121. Here, it is desirable that the gas is dry air that does not
include humidity. When the gas such as the dry air is only injected
into the cooling chamber 150, the vapor remaining in the cooling
chamber 150 after performing the cooling of the heating plate 100
can be removed.
[0055] FIG. 6B is a graph illustrating a cooling method of a heat
treatment apparatus according to another exemplary embodiment of
the present invention. Referring to FIG. 6B, the liquid droplet
aerosol is injected into the cooling chamber 150 by the atomizing
unit 120 for a predetermined time t2 in a pulse form. In that
process, the cooling liquid is supplied to the cooling chamber 150
intermittently in a pulse form through the first nozzle 122, and
the gas is supplied to the cooling chamber 150 continuously through
the second nozzle 121. Accordingly, the heating plate 100 is cooled
down to the desired temperature by the evaporation of the injected
liquid droplet aerosol.
[0056] In order to remove the vapor remaining in the cooling
chamber 150 after performing the cooling of the heating plate 100,
the gas is only injected into the cooling chamber 150 by the
atomizing unit 120 for a predetermined time. In that process, the
gas such as the dry air is supplied into the cooling chamber 150
through the second nozzle 121.
[0057] As described above, according to the heat treatment
apparatus of the present invention, since the liquid droplet
aerosol evaporates by contacting directly the heating plate to cool
down the heating plate in the phase changing method, the cooling
performance is improved.
[0058] In addition, the atomizing unit installed on the chamber
case generates the liquid droplet aerosol by mixing the cooling
liquid and gas, and at the same time, injects the liquid droplet
aerosol into the cooling chamber. Thus, the supplied liquid droplet
aerosol is not lost, and the heating plate can be cooled down to
the desired temperature rapidly.
[0059] Also, since the liquid droplet aerosol is discharged through
the discharge hole in the vapor state after being evaporated, the
discharge device can be constructed in a simple structure without
any possibility of leakage as in the conventional heat treatment
apparatus using a liquid cooling method.
[0060] In the process of fabricating the semiconductor, a wafer
baking process and a cooling process can be performed using one
bake unit, thus improving the productivity.
[0061] While the present invention has been particularly shown and
described with reference to exemplary embodiments thereof, it will
be understood by those of ordinary skill in the art that various
changes in form and details may be made therein without departing
from the broad spirit and scope of the present invention as defined
by the following claims.
* * * * *