U.S. patent application number 10/370372 was filed with the patent office on 2003-11-27 for water supply apparatus and method thereof.
This patent application is currently assigned to LAM RESEARCH CORPORATION. Invention is credited to Haikata, Eri, Isago, Yoichi, Kobayashi, Naoaki, Nakajima, Shu, Nojiri, Kazuo, Ori, Kohsuke, Tajima, Kaori, Yamaguchi, Ryuta.
Application Number | 20030217762 10/370372 |
Document ID | / |
Family ID | 29551654 |
Filed Date | 2003-11-27 |
United States Patent
Application |
20030217762 |
Kind Code |
A1 |
Kobayashi, Naoaki ; et
al. |
November 27, 2003 |
Water supply apparatus and method thereof
Abstract
A water supply apparatus and a method thereof have a high
capability of peeling-off and removing unnecessary objects such as
a resist film, and parameters for setting efficient water supply
conditions. The water supply apparatus and the method are designed
to supply water for cleaning, peeling-off, or treating a target
article. On a surface of the target article to be processed, a
nozzle device is provided for spraying a mixture of water vapor and
water mist. At least the following parameters are respectively set
as water supply conditions to proper values so as to supply water
to the target article, and these parameters include (1) a weight
ratio of water vapor to water mist on the surface to be processed,
(2) a temperature of the surface to be processed, and (3) a
distance between a (water) blowing port of the nozzle device and
the surface to be processed.
Inventors: |
Kobayashi, Naoaki; (Chiba,
JP) ; Yamaguchi, Ryuta; (Tokyo, JP) ; Tajima,
Kaori; (Kanagawa, JP) ; Ori, Kohsuke; (Tokyo,
JP) ; Haikata, Eri; (Tokyo, JP) ; Nakajima,
Shu; (Kanagawa, JP) ; Isago, Yoichi;
(Kanagawa, JP) ; Nojiri, Kazuo; (Tokyo,
JP) |
Correspondence
Address: |
Chester E. Martine, Jr.
MARTINE & PENILLA, LLP
710 Lakeway Drive, Suite 170
Sunnyvale
CA
94085
US
|
Assignee: |
LAM RESEARCH CORPORATION
Fremont
CA
94538
|
Family ID: |
29551654 |
Appl. No.: |
10/370372 |
Filed: |
February 18, 2003 |
Current U.S.
Class: |
134/2 ; 134/18;
134/35; 134/56R; 134/95.3 |
Current CPC
Class: |
B05B 7/0433 20130101;
H01L 21/67051 20130101; B05B 7/066 20130101; B08B 3/02 20130101;
B05B 7/0475 20130101; B05B 7/0807 20130101; B08B 7/00 20130101 |
Class at
Publication: |
134/2 ; 134/18;
134/35; 134/56.00R; 134/95.3 |
International
Class: |
C23G 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 10, 2002 |
JP |
JP 2002-136159 |
Feb 18, 2002 |
JP |
JP 2002-40739 |
Claims
What is claimed is:
1. Apparatus for supplying water for treating a target article,
comprising: a system for converting the water to water vapor and
water mist; and a nozzle having a main port for spraying the water
vapor and water mist onto a surface of the target article; wherein
the system is configured to set values of parameters to proper
values for optimizing treatment of the target article, the
parameters being taken from the group consisting of: a weight ratio
of the water vapor to the water mist sprayed onto the surface to be
treated, a temperature of the surface to be treated, and a distance
between the nozzle and the surface to be treated.
2. An apparatus according to claim 1, wherein the system is
configured to set a value of the weight ratio of water vapor to
water mist, the value is in a range of about 20 to 80 weight %.
3. An apparatus according to claim 1, wherein the system is
configured to set a value of the temperature of the surface to be
treated, the value is in a range of about more than 50 to about
less than 150.degree. C.
4. An apparatus according to claim 1, wherein the system is
configured to set a value of the distance between the nozzle and
the surface to be treated, the value is lower than about 30 mm.
5. An apparatus according to claim 1, wherein: the target article
is a semiconductor wafer, and the treatment is the removal from the
surface of the target article of an unnecessary object in the form
of one or more of a resist or a polymer residue, and the configured
system sets the following values for the parameters: for the weight
ratio of water vapor to water mist, values in a range of about 20
to 80 weight %; for the temperature of the surface, values in a
range of about more than 50 to about less than 150.degree. C.; and
for the distance between the nozzle and the surface, values lower
than about 30 mm.
6. An apparatus according to claim 1, wherein the nozzle consists
of two separate nozzles, one of the nozzles being for the water
vapor and one of the nozzles being for the water mist, the water
vapor nozzle and the water mist nozzle being coaxial and each
terminating in a respective water vapor port and water mist port,
the water vapor and water mist ports of the respective nozzles
being configured to direct the water vapor and the water mist
through the main port and downwardly toward the surface.
7. An apparatus according to claim 1, wherein; the system consists
of a separate annular-shaped heated water conduit configured with a
first discharge port and to supply the water as water mist into a
space adjacent to the first discharge port, the system further
consists of a water vapor supply conduit within the heated water
conduit and configured with a second discharge port adjacent to the
first discharge port to discharge the water vapor into the space;
and the main port receives the water vapor and the water mist and
sprays the water vapor and water mist onto the surface of the
article.
8. Apparatus for removing an unnecessary object from a target
article using only water and one or more gases, comprising: a
system for converting the water to water vapor and water mist, each
of the water vapor and water mist comprising one or more of the
gases; a nozzle having a port for directing a mixture of the water
vapor and the water mist onto a surface of the target article on
which the unnecessary object is located, wherein there is a weight
ratio of the water vapor to the water mist that is directed to the
surface to be treated, wherein the surface has a temperature, and
wherein the nozzle directs the water vapor and the water mist
through a distance from the nozzle to the surface; and a controller
configured to cause the system to set values of one or more
parameters to proper values for optimized removal of the
unnecessary object from the target article, the parameters being
taken from the group consisting of: the weight ratio of the water
vapor to the water mist directed to the surface, the temperature of
the surface, and the distance from the nozzle to the surface of the
unnecessary object.
9. An apparatus according to claim 8, wherein the controller causes
the system to set a value of the weight ratio of water vapor to
water mist directed onto the surface, wherein the value is in a
range of about 20 to 80 weight %.
10. An apparatus according to claim 8, wherein the controller
causes the system to set a value of the temperature of the surface,
wherein the value is in a range of about more than 50 to about less
than 150.degree. C.
11. An apparatus according to claim 8, wherein the controller
causes the system to set a value of the distance from the nozzle to
the surface, wherein the value is lower than about 30 mm.
12. An apparatus according to claim 8, wherein: the target article
is a semiconductor wafer, and the treatment is the removal from the
surface of the target article of one or more of a resist or a
polymer residue, and the controller is configured to cause the
parameters to be set with the following respective values: for the
weight ratio, values in a range of about 20 to 80 weight %; for the
temperature of the surface, values in a range of about more than 50
to about less than 150.degree. C.; and for the distance from the
nozzle to the surface, values lower than about 30 mm.
13. An apparatus according to claim 8, wherein a peeling-off time
represents a period of time required to remove resist or residue as
the unnecessary object to bow removed from the surface, and
wherein: the controller is configured to cause the parameters to be
set with the following respective values: for the weight ratio, a
weight ratio value in the range of about 20 to 80 weight %, the
weight ratio value being selected so that the peeling-off time
resulting from use of the selected weight ratio value is
substantially less than peeling-off times corresponding to use of
other weight ratio values; for the temperature of the surface, a
temperature value in the range of about more than 50 to about less
than 150.degree. C., the temperature value being selected so that
the peeling-off time resulting from use of the selected temperature
value is substantially less than peeling-off times corresponding to
use of other temperature values; and for the distance from the
nozzle to the surface, a distance value lower than about 30 mm, the
distance value being selected so that the peeling-off time
resulting from use of the selected distance value is substantially
less than peeling-off times corresponding to use of other distance
values.
14. Apparatus for removing resist from a surface of a semiconductor
wafer using only water, or only water and one or more gases, the
one or more gases being taken from the group consisting of argon,
nitrogen, and helium, the apparatus comprising: a system for
converting the water to water vapor and water mist; a nozzle having
a main port for directing a mixture of the water vapor and the
water mist onto the resist on the surface of the semiconductor
wafer, wherein there is a weight ratio of the water vapor to the
water mist that is directed to the resist, wherein the surface has
a temperature, and wherein the nozzle directs the water vapor and
the water mist through a distance from the nozzle to the surface;
and a controller configured to cause the system to set values of
one or more parameters to proper values for optimized removal of
the resist from the semiconductor wafer, the parameters being taken
from the group consisting of: the weight ratio of the water vapor
to the water mist directed to the resist on the surface, the
temperature of the surface, and the distance from the nozzle to the
surface of the resist.
15. A method for removing a material from a surface of a target
article, comprising the operations of: supplying water for the
removing by one of cleaning, peeling-off and working of the target
article; defining parameters for water vapor and water mist to be
directed onto the target article, the parameters having proper
values for optimizing the removal of the material, the parameters
including one or more of: a weight ratio of the water vapor to the
water mist directed onto the surface, a temperature of the surface,
and a distance between a point from which the directing starts to
the surface; and converting the water to a mixture of the water
vapor and the water mist, the water vapor and the water mist having
the proper values and being directed onto a surface of the target
article.
16. A method according to claim 15, wherein the target article is a
semiconductor wafer and the material is one of a resist and a
polymer, the method further comprising the operation of: causing
the parameters to be set with the following respective values: for
the weight ratio, values in a range of about 20 to 80 weight %; for
the temperature of the surface, values in a range of about more
than 50 to about less than 150.degree. C.; and for the distance
between the point and the surface, values lower than about 30
mm.
17. A method according to claim 15, wherein a peeling-off time
represents a period of time required to remove the resist or the
polymer from the surface, and wherein: the causing operation is
effective to select the weight ratio value so that the peeling-off
time resulting from use of the selected weight ratio value is
substantially less than peeling-off times corresponding to use of
other weight ratio values; the causing operation is effective to
select the value of the temperature of the surface so that the
peeling-off time resulting from use of the selected temperature
value is substantially less than peeling-off times corresponding to
use of other temperature values; and the causing operation is
effective to select the value of distance between the nozzle and
the surface so that the peeling-off time resulting from use of the
selected distance value is substantially less than peeling-off
times corresponding to use of other distance values.
18. A method according to claim 15, wherein the converting
operation is performed by one of the following: directing a spray
material comprising a mixture of water vapor and water mist, or
directly ejecting pressurized hot water from a port to cause
boiling due to pressure reduction during the directing to form the
water vapor and the water mist.
19. A method for supplying water to remove a material from a target
article, comprising the operations of: defining one or more
parameters for water vapor and water mist directed from a nozzle to
a surface of the material on the target article, the parameters
being selected from: a weight ratio of the water vapor to the water
mist directed onto the surface, a temperature of the surface, and a
distance between the nozzle and the surface; and supplying the
water vapor and the water mist directed onto the surface under the
control of one or more of the defined parameters, the value of the
one or more of the defined parameters being set to a proper value
to optimize the removal of the material from the surface.
20. A method according to claim 19, wherein the supplying operation
consists of selecting the following parameters with a respective
value in the following ranges: for the weight ratio, a value in a
range of about 20 to 80 weight %; for the temperature of the
surface, a value in a range of about more than 50 to about less
than 150.degree. C.; and for the distance between the nozzle and
the surface, a value lower than about 30 mm.
21. A method according to claim 19, wherein the material is a
resist or a polymer on the surface, and a peeling-off time
represents a period of time required to remove the resist or the
polymer from the surface, and wherein: the supplying operation
under the control of one or more of the defined parameters is
performed to select the values of the parameters as follows: the
weight ratio value so that the peeling-off time resulting from use
of the selected weight ratio value is substantially less than
peeling-off times corresponding to use of other weight ratio
values; the value of the temperature of the surface so that the
peeling-off time resulting from use of the selected temperature
value is substantially less than peeling-off times corresponding to
use of other temperature values; and the value of the distance
between the nozzle and the surface so that the peeling-off time
resulting from use of the selected distance value is substantially
less than peeling-off times corresponding to use of other distance
values.
22. A method according to claim 21, the method further comprising
the operation of: determining whether the peeling-off removal is at
a desired amount of removal; and continuing the supplying operation
until the peeling-off removal is at the desired amount of removal.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to apparatus and
methods for supplying water (H.sub.2O) in a product manufacturing
process, the water having high purity and, for example, to be used
for removal operations, which may include surface working of,
washing, or peeling-off from, the product. More specifically, the
invention relates to a water supply apparatus and methods for
treating the product, as in a peeling-off operation, i.e., removing
unnecessary materials or objects (herein called "unnecessary
objects", or "objects") from the product, which product may also be
referred to as a "target article". The products, or target
articles, may be a semiconductor wafer, hard disk (HD), liquid
crystal display (LCD) or flat panel display (FPD)), for example.
The objects may be a resist film deposited on a surface of the
target article in a lithography step, or may be a polymer residue
or the like deposited in an etching step.
[0003] 2. Description of the Related Art
[0004] In a process of manufacturing such target articles, a resist
is coated on a surface of such target articles, and precision
machining is carried out to form a pattern or the like on the
surface of the target articles. Then, unnecessary objects, such as
a resist film and a polymer residue deposited on the surface of the
target articles, are removed.
[0005] Technologies available for removing unnecessary objects,
such as the resist film, include a plasma ashing method for ashing
and removing the resist film by oxygen plasma; a method for
heating, dissolving and removing the film by an organic solvent
(solvent containing phenol, halogen or the like); a method of
heating and dissolving by concentrated sulfuric acid/hydrogen
peroxide; and the like.
[0006] However, all the above-described methods need time, energy
and chemical materials for decomposing and dissolving the resist
film and the like, and investment in the steps of decomposing and
removing the resist film or the like is large. In the case of
peeling-off the resist film by a generally used plasma asher, many
facilities are necessary. These may include a vacuum device/plasma
source, semiconductor gas, complicated devices, and a controller
for vacuum control, plasma stability control and the like.
Consequently, such facilities present problems of large size, high
costs and the like. In the case of using wet cleaning, many process
devices may be required and many environmental concerns must be
taken into consideration in dealing with a great quantity of
chemical solution, high-temperature chemical solution control,
waste solution, drainage and the like.
[0007] Therefore, in the technical field of surface precision
machining, including technology for removing such unnecessary
objects, there is a need, for example, to provide systems and
methods using materials presenting low or minimal impact on the
environment. Such systems and methods would depart from the
conventional technology of using chemical materials and chemical
treatment, and there has been an expectation for use and
development of this system.
[0008] The inventors filed a patent application No. 2001-264627,
dated Aug. 31, 2001, "Water Supplying Apparatus and Water Supplying
Method" (the "Prior Application"). Although such apparatus and
methods of the Prior Application departed from the conventional
technology, there is still a need for improved efficiency of
surface working of, washing, or peeling-off from, the target
article, and for less impact on the environment in the removal of
unnecessary objects from target articles, for example.
SUMMARY OF THE INVENTION
[0009] Broadly speaking, the present invention is an improvement on
the Prior Application, and fills these and other needs by providing
a water supply apparatus and methods capable of supplying water
mist and water vapor that is mixed, and sprayed and directed onto
the target article under controlled conditions so as to cause a
removal operation to be performed, such as peeling-off of
unnecessary objects from the target article, for example. As a
result, the present invention enables the removal operation to be
executed more efficiently and effectively than conventionally in
processes such as resist peeling-off, polymer removal, cleaning and
the like, and to achieve process simplification, zero emission and
other objectives.
[0010] In order to fill these needs, the present invention may be
configured in a number of embodiments, such as the following. A
water supply apparatus is provided for supplying spray material to
perform a treatment such as cleaning of, peeling-off from, or
surface working of, a target article. The apparatus may include a
system for converting the water to the spray material, which may be
in the form of water vapor and water mist. The apparatus may also
include a nozzle for spraying and directing the spray material to a
surface of the target article. Water supply parameters are defined
and set to proper values so that the water vapor and water mist may
be supplied to the target article to achieve optimum removal
results. The water supply parameters may include at least (1) a
weight ratio of the water vapor to the water mist supplied to the
surface of the target article to be processed, (2) a temperature of
such surface to be processed, and (3) a distance between a blowing
(or discharge) port of the nozzle device and the surface to be
processed.
[0011] In one embodiment of the water supply apparatus of the
present invention, the apparatus may be configured to separately
supply water vapor and water mist to the nozzle, and the nozzle is
configured with coaxial passages to respectively receive the
separate water vapor and water, and to mix the water vapor and the
water mist, which is directed from the nozzle device to direct the
resulting spray material toward the target article.
[0012] In another embodiment of the water supply apparatus of the
present invention, the apparatus may be configured so that the
nozzle directly blows and directs pressurized hot water toward the
target article, so that boiling occurs as and after the pressurized
hot water exits the nozzle under the set water supply parameters.
The boiling occurs due to pressure reduction during the blowing and
directing, to form water vapor and water mist.
[0013] In a further embodiment of the water supply apparatus of the
present invention, a separate annular-shaped water vapor conduit
supplies water vapor adjacent to a discharge port of a high
pressure liquid water supply conduit, so that upon mixing of the
liquid water and the water vapor, water vapor and water mist are
formed and discharged from a main discharge port.
[0014] In a still further embodiment of the water supply apparatus
of the present invention, a separate annular-shaped heated water
conduit supplies water adjacent to a discharge port of a water
vapor supply conduit so that upon mixing of the heated liquid water
and the water vapor, water vapor and water mist are formed and are
discharged from a main discharge port.
[0015] In one parameter control embodiment of the water supply
apparatus of the present invention, one of the water supply
parameters, the weight ratio of water vapor to water mist on the
surface to be processed, may be set to be in a range of about 20 to
80 weight %.
[0016] In another parameter control embodiment of the water supply
apparatus of the present invention, another of the water supply
parameters, the temperature of the surface to be processed, may be
set in a range of more than 50 to less than 150.degree. C.
[0017] In a further parameter control embodiment of the water
supply apparatus of the present invention, another of the water
supply parameters, the distance between the blowing port of the
nozzle device and the surface to be processed, is set lower than
about 30 mm. to about 5 mm.
[0018] In a yet further embodiment of the present invention, a
method for supplying water to perform a removal treatment, such as
cleaning of, peeling-off from, or working of, a target article, may
include an operation of defining parameters (e.g., water supply
parameters), and another operation may supply water vapor and water
mist to a surface of the target article to be processed under the
control of at least one of the defined water supply parameters. In
the supplying, the water supply parameters are set to proper
values, and may include at least (1) a weight ratio of the water
vapor to the water mist directed onto the surface of the target
article to be processed, (2) a temperature of such surface to be
processed, and (3) a distance between a water blowing port and such
surface to be processed.
[0019] In an additional embodiment of the method of the present
invention, in the water supply operation, water supply facilities
are provided to supply both the water vapor and water mist, which
are directed as a spray material toward the target article. Before
the directing operation, the water vapor and the water mist are
mixed. One aspect of the additional embodiment may include the
water supply operation providing pressurized hot water released
from a high-pressure container into a lower-pressure container to
cause boiling of the hot water due to pressure reduction during the
release to thereby form water vapor and water mist. The hot water
supply may be provided through one or more blowing ports of the
high-pressure container, which may be a nozzle, for example.
[0020] In a yet other embodiment of the method of the present
invention, the weight ratio of water vapor to water mist directed
to the surface to be processed is set in a range of above about 20
to below about 80 weight %.
[0021] In one more embodiment of the method of the present
invention, the temperature of the surface to be processed is set in
a range of above about 50 to below about 150.degree. C.
[0022] In a still further embodiment of the method of the present
invention, the distance between the water blowing port and the
surface to be processed is set in a range from lower than about 30
mm to about 5 mm.
[0023] According to the water supply apparatus and the water supply
method of the present invention, the weight ratio of water vapor to
water mist on the surface to be processed is preferably set in a
range of above about 20 to below about 80 weight %, and more
preferably in a range of 20 to 60 weight %, and still more
preferably at about 50 weight %.
[0024] According to the water supply apparatus and water supply
method of the present invention, the temperature of the surface to
be processed is preferably set in a range of above about 50 to
below about 150.degree. C., and more preferably in a range of about
70 to about 130.degree. C., and most preferably in a range of from
about 100 to about 120.degree. C.
[0025] According to the water supply apparatus and the water supply
method of the present invention, the distance between the blowing
port(s) of the nozzle and the surface to be processed may be in a
range of about 30 mm to about 100 mm and be valid for cleaning,
surface working, and peeling-off, and more preferably the distance
is set to be lower than about 30 mm.
[0026] According to the water supply apparatus and method of the
present invention, parameters other than the above-described
Parameters (1) to (3) may be provided. Specifically, for example,
parameters of (4) a spraying pressure or a speed of a spray
material through the nozzle, and (5) a total amount of water vapor
and water mist, may be set. The apparatus and method of the present
invention can be constructed by including one or both of these
additional parameters.
[0027] Other aspects and advantages of the present invention will
become apparent from the following detailed description, taken in
conjunction with the accompanying drawings, illustrating by way of
example t-he principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The present invention will be readily understood by
reference to the following detailed description in conjunction with
the accompanying drawings, in which like reference numerals
designate like structural elements.
[0029] FIGS. 1(a) and 1(b) are respective schematic structure views
of water vapor and water mist used in the present invention;
[0030] FIG. 2(a) is a schematic view of an exemplary configuration
of an apparatus and method according to the present invention for
supplying water vapor and water mist under controlled conditions
for removing unnecessary objects from a target article;
[0031] FIGS. 2(b) through 2(g) are schematic views of other
configurations of the present invention for supplying a mixture of
water vapor and water mist under the controlled conditions for
removing the unnecessary objects from the target article;
[0032] FIG. 3 is a graph relating to the present invention and
showing a relationship between a peeling-off percentage (of a
resist film from a target article when a spray material is supplied
from a nozzle), and a surface temperature (.degree. C.) of the
target article;
[0033] FIG. 4 is a graph relating to the present invention and
showing a relationship between a peeling-off percentage (of the
resist film) on the surface of the target article) and a clearance
(or distance) between a blowing port of the nozzle device (which
supplies the spray material) and a surface of the target article to
be processed;
[0034] FIG. 5 is a graph showing a relationship between resist
peeling-off time (in seconds) and the weight ratio of a mixture of
water vapor and water mist (directed against resist as an
unnecessary object on a target article according to the present
invention), which peeling-off time is the time required to
completely peel-off resist from the target article in the operation
of the apparatus and method of the present invention;
[0035] FIG. 6 is a bar graph showing a relationship between the
distance between the blowing port of the nozzle and the surface of
the target article to be processed, and the temperature of the
surface of the target article that is subjected to the water vapor
and the water mist from the nozzle in the operation of the present
invention;
[0036] FIG. 7(a) is a graph related to the apparatus and method of
the present invention, showing a relationship between spraying
pressure of the spray material M (which may be another parameter),
and the weight ratio of the spray material M (i.e., of the mixture
of the water vapor and the water mist) directed against the surface
of the target article;
[0037] FIG. 7(b) is a graph related to the apparatus and method of
the present invention, showing a relationship between vapor
pressure of the water vapor, and temperature; and
[0038] FIG. 8 is a flow chart illustrating an embodiment of a
method of the present invention in which parameters for the control
of a removing operation may be defined to include at least one or
more of: (1) a weight ratio of the water vapor to the water mist
directed onto the surface of the target article to be processed,
(2) a temperature of such surface to be processed, and (3) a
distance between a discharge port of the nozzle device and the
surface to be processed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] An invention is described for controlling parameters in the
supply of water mist and water vapor that is mixed, sprayed, and
directed onto a target article so as to cause removal of
unnecessary objects from the target article. The present invention
is described in more detail in terms of enabling a peeling-off
treatment to be executed more efficiently and effectively than
conventionally in removal processes such as resist peeling-off; and
in terms of polymer removal, cleaning and the like; and achieving
process simplification, zero emission and other objectives. It will
be obvious, however, to one skilled in the art, that the present
invention may be practiced without some or all of these specific
details. In other instances, well known process operations have not
been described in detail in order not to obscure the present
invention.
[0040] Referring to FIGS. 1(a) and 1(b), there are schematically
shown respective exemplary structures of water vapor 12 (also
referred to as "water steam") and water mist 14 provided by the
present invention. As to the example shown in FIG. 1(a), the term
"water vapor" refers to water 15 (see arrow 15 in FIG. 2(a)) in a
vaporized state. The vaporized state results from liquid water 15,
such as deionized water (DIW), that has been heated and transformed
into water molecules (represented by the dark circles 16 in FIG.
1(a)) that are generally in air 17. The water molecules 16 may also
be referred to as "vaporized water". While the water molecules 16
of the vaporized state are generally present in air 17, the water
molecules 16 may be present in other gases, such as nitrogen,
argon, or helium. Also, 100% water vapor (i.e., containing 100%
vaporized water 16 and no air or gas 17) can be used. The water
vapor 12 may be maintained in the desired described condition by
controlling the temperature of the water vapor 12 to be higher than
100.degree. C. under an atmospheric pressure, and is preferably 130
to 160.degree. C.
[0041] As to the example shown in FIG. 1(b), the term "water mist"
refers to liquid water 15 (such as DIW) that has been heated to
less than 100.degree. C. and acted on to transform the heated
liquid water 15 into liquid water particles 18 contained in air, or
other gases, such as nitrogen, argon, or helium. The particles 18
are larger than the water molecules 16. The water mist 14 may be
maintained in the desired described condition by controlling the
temperature of the water mist 14 to be less than 100.degree. C.
under an atmospheric pressure.
[0042] In general, water vapor 12 containing vaporized water 16 in
gas 17 can be generated by, for example, dropping liquid DIW 15
onto a heating plate and vaporizing the liquid DIW 15, by heating
the liquid water 15, or by directly blowing pressurized hot water
15 and causing boiling by a pressure reduction during the
blowing.
[0043] In general, water mist 14 can be generated by, for example,
forcibly ejecting liquid DIW 15 of a normal temperature (i.e., room
temperature), or a mixture of liquid DIW 15 and gas 19; spraying
water 15 to the vicinity of an ejection port 21 (see port 21-1 in
FIG. 2(a)), (in each case referred to as a so-called "spraying
principle"); or by directly blowing pressurized hot water 15 and
causing boiling by a pressure reduction during the blowing.
[0044] Various embodiments of the present invention are identified
using reference numbers. Specific embodiments of the present
invention are identified using reference numbers with a "-#", such
as "21-1", for example.
[0045] FIG. 2(a) schematically shows a first embodiment 22-1 of an
apparatus 22 of the present invention. A treatment chamber 23 is
provided to contain a flat or planar target article 24, such as a
semiconductor wafer disposed (loaded) on a table 26 rotated by a
rotary shaft 27. An embodiment 31-1 of a nozzle device 31 is
configured to contain high pressure, and may be a nozzle 32-1
having a blowing (or ejection) port 21-1. The port 21-1 of the
device 31-1 is disposed oppositely to a surface 33 of the target
article 24 to be processed. The surface 33 is located away from the
port 21-1 by a predetermined clearance (also referred to as a gap
or distance) H. A supply passage, such as a pipe, 34 is connected
to the device 31-1. This passage 34 is also connected to an
intermediate device 40-1, and water 15 (such as DIW) is supplied to
the device 40-1 from a second pipe (or passage) 41. For removal of
any of the above-described unnecessary objects from the surface 33
of the target object 24, the target article 24 is set on the table
26 to be rotated at a predetermined speed and the pressure in the
chamber 23 may be controlled by reference to a gauge 23G, for
example, and adjusting the pressure in the chamber 23 by use of an
air inlet 36.
[0046] In a general sense, FIG. 2(a) shows that under high water
pressure contained by the nozzle 32-1, a spray material M' exits
from the port 21-1, and is sprayed and directed as spray material M
to the surface 33. The port 21-1 is shown located in a discharge
tip side 42 of the nozzle 32-1. The nozzle 32-1 is scanned in a
radial direction of the target article 24. The spray material M
impacting onto the surface 33 performs the removal operations
(e.g., the surface cleaning, or resist peeling-off, are carried
out).
[0047] With respect to FIGS. 2(a) through 2(g), the spray material
M' and the spray material M are referred to separately to
facilitate description of various embodiments of the apparatus 22
of the present invention. In each embodiment, the spray material M'
is emitted from the port 21 of the nozzle 32, and is directed by
and sprayed as the spray material M to the surface 33 to be
processed. These embodiments may be configured and operated so that
the spray materials M and M' may be similar to each other, or
different from each other, as described below.
[0048] For example, still referring to FIG. 2(a), the first
embodiment 22-1 of the apparatus 22 provides different spray
materials M' and M. Pressurized hot water 15 forms the spray
material M' (shown within the nozzle 32-1). The water 15 may be DIW
that is heated and pressurized by the device 40-1. The pressurized
heated water 15 flows in the pipe 34 to the first embodiment 31-1
of the nozzle device 31. The hot pressurized water 15 (i.e., the
spray material M') is directly blown out of (e.g., ejected from or
exits) the single port 21-1. It may be understood that the device
40-1 and the nozzle 32-1 from the pipe 34 to the tip side 42 define
a system for converting the hot pressurized water 15 to the water
vapor 12 and water mist 14. In detail, as and after the hot
pressurized water 15 exits the port 21-1, the spray material M is
generated in the chamber 23 by boiling caused by a pressure
reduction during the ejection from the port 21-1. The spray
material M is in the form of the water vapor 12 and the water mist
14. Thus, the port 21-1 of the nozzle 32-1 is effective for
spraying the water vapor 12 and the water mist 14, which form the
spray material M. The spray material M flows (or is sprayed) to the
surface 33 to processed. In the first embodiment 22-1, as the spray
material M flows to the surface 33, some of the water molecules 16
(i.e., some of the vaporized water 16 shown in FIG. 1(a)) may cool
and form the lower temperature water mist 14 having the larger
water particles 18. As described below, the flow of the spray
material M and the processing of the article 24 may be under
controlled conditions, such as by having a proper value set for one
or more of the parameters to control the removing treatment. These
controlled conditions may be provided by a controller 43, and an
embodiment 43-1 shown in FIG. 2(a) may be connected to the device
40-1 and to the inlet 36 (e.g., to a valve thereof) for such
control. In this manner, with these values and as described more
fully below, the treatment of the article 24 may be optimized.
[0049] Referring to FIGS. 2(b), 2(c), and 2(d), the spray materials
M' and M may be similar in a second embodiment 22-2 of the
apparatus 22. FIG. 2(b) shows a second embodiment 40-2 of the
device 40 separately supplying the water vapor 12 and the water
mist 14. The device 40-2 may include a DIW water mist supply 44.
The DIW water mist supply 44 provides room-temperature DIW water
mist 14 to a second embodiment 34-2 of the pipe 34. The embodiment
34-2 may be in the form of a dual-flow pipe having a separate water
mist channel 34-2M and a separate water vapor channel 34-2V. The
pressure of the water mist 14 may be controlled by an embodiment
46-2 of a flow controller 46 of the device 40-2. The flow
controller 46-2 may be connected to the controller 43-2 to set
values of the parameters, such as a value of the weight of the
water mist 14 supplied to the pipe 34-2M and then to the nozzle
32-2.
[0050] The device 40-2 may also include a steam generator 45 that
supplies water vapor 12 to the water vapor channel 34-2V. A
pressure valve 48 and an indicator (pressure gauge) 49 enable
control of the water vapor 12 to the channel 34-2V, such control
may be provided by the controller 43-2 connected to the pressure
valve 48, to set values of the parameters, such as a value of the
weight of the water vapor 12 supplied to the pipe 34-2V and then to
the nozzle 32-2.
[0051] It may be understood that the device 40-2 and the pipes
34-2M and 34-2V define another system for converting water 15 input
to the DIW supply 44 and to the steam generator 45. The conversion
is to the respective water vapor 12 and water mist 14.
[0052] The embodiments 34-2M and 34-2V of the pipe 34-2 separately
carry the water vapor 12 and the water mist 14 to a respective
second or a third embodiment 31-2 or 31-3 of the nozzle device 31,
to form the spray material M'. FIG. 2(c) shows the nozzle device
31-2 as having two separate nozzles 32-2, including one nozzle
32-2V for the water vapor 12 and one nozzle 32-2M for the water
mist 14. The spray material M' flows through the respective nozzles
32-2 to respective ports 21-2V and 21-2M. The port 21-2V is for the
water vapor 12 and a port 21-2M is for the water mist 14. The spray
material M' (in the form of each separate flow stream of the water
vapor 12 and the water mist 14) is blown out of (i.e., exits, is
ejected from, directed and sprayed) the respective ports 21-2V and
21-2M and into the chamber 23. The spray material M' that is
directed into the chamber 23 and toward the surface 33 is in the
form of the spray material M that is similar to the separate water
vapor 12 and water mist 14 of the spray material M', but the water
vapor 12 and water mist 14 are now mixed in the chamber 23. The
spray material M is directed by the nozzle device 31-2 and flows to
the surface 33. As described below, the flow of the spray material
M and the processing of the article 24 may be under controlled
conditions, provided for example, by the controller 43-2. The
controlled conditions may be having a proper value set for one or
more of the parameters to control the removing treatment.
[0053] FIG. 2(d) shows another embodiment 31-3 of the nozzle device
31 as having two separate nozzles 32-3, one nozzle 32-3V for the
water vapor 12 and one nozzle 32-3M for the water mist 14. The
spray material M' flows through the respective nozzles 32-3 to
respective ports 21-3V and 21-3M. In this embodiment 31-3, the
nozzles 32-3V and 32-3M, and the respective ports 21-3V and 21-3M,
are coaxial and provide a preferred embodiment because the nozzles
32-3V and 32-3M, and the respective ports 21-3V and 21-3M, direct
the respective water vapor 12 and water mist 14 more downwardly
toward the surface 33. The port 21-3V is for the water vapor 12 and
the port 21-3M is for the water mist 14. The spray material M' (in
the form of each separate flow stream of the water vapor 12 and the
water mist 14) is blown out of (i.e., exits, is ejected from,
directed and sprayed), the respective ports 21-3V and 21-3M and is
directed into the chamber 23 to the surface 33.
[0054] Referring to FIGS. 2(e), 2(f), and 2(g), the spray materials
M' and M may be different in a third embodiment 22-3 of the
apparatus 22. FIG. 2(e) shows a third embodiment of the device 40-3
for separately supplying the water vapor 12 and heated water 15H.
The device 40-3 may include an electric water heater 51 to which
DIW 15 is supplied from a DIW supply 52. The heater 51 provides
heated DIW water (e.g., heated to a temperature below 100 degrees
C.) to a valve 53 connected to a flow meter 54.
[0055] The flow meter 54 is connected to a third embodiment 32-3 of
the nozzle 32. FIG. 2(f) shows the embodiment 32-3 in the form of
one embodiment 32-3VH of a dual-flow nozzle 32 having a separate
water vapor channel 34-3V and a separate heated water channel
34-3H.
[0056] The heater 51 may be a boiler having the capability of
supplying the lower temperature DIW 15H to the valve 53, and a
capability of supplying steam (or water vapor 12) at temperatures
such as 130 to 150 degrees C. to an outlet 56 that supplies water
vapor 12 to a pressure gauge 57 connected to a valve 58. The valve
58 is connected to a pressure regulator 59 connected to the water
vapor channel 34-3V of the nozzle 32-3. The pressure valve 58 and
the regulator 59 enable control of the pressure and flow rate of
the water vapor 12 supplied to the channel 34-3V (FIG. 2(f)).
[0057] To provide the controlled conditions described below, a
third embodiment of the controller 43-3 may operate by having a
proper value set for one or more of the parameters to control the
removing treatment. For this purpose, the controller 43-3 is
connected to the heater 51, to the valves 53 and 58, to the flow
meter 54, and to the pressure regulator 59. Thus, the temperature,
pressure and flow rate of the DIW water 15 and of the water vapor
12, may be adjusted to provide the parameter control described
below.
[0058] The nozzle embodiment 32-3 of embodiment 22-3 may be used
with either of two nozzle configurations, one provided by the
nozzle embodiment 32-3VH shown in FIG. 2(f), and the other by a
nozzle embodiment 32-3HV shown in FIG. 2(g). These embodiments
32-3VH and 32-3HV are similar in that both have the channels 34-3V
and 34-3H, and such channels are coaxially arranged. The
embodiments differ according to which channel is interior or
exterior of the other channel. As shown in FIG. 2(f), the water
vapor channel 34-3V is the exterior coaxial channel, whereas in
FIG. 2(g) the heated water channel 34-3H is the exterior coaxial
channel. In each case, the arrangement of the channels 34-3
separately guides the respective water vapor 12 and heated water 15
to a respective port 21-3. In FIG. 2(f), there is shown a port
21-3H directing the water 15H into a space between a port 21-3WV.
As the water 15H enters the space the water 15H is transformed into
the water mist 14. The port 21-3WV supplies the water vapor 12 to
that space. A main port 21-3VH directs both the water vapor 12 and
the water mist 14 out of the nozzle 32-3VH and toward the surface
33.
[0059] In FIG. 2(g), a port 21-3V directs the water vapor 12 into a
space adjacent to the port 21-3V. A port 21-3H directs the heated
water 15H into the space, where the water 15H is transformed into
water mist 14. A main port 21-3HV directs both the water vapor 12
and the water mist 14 out of the nozzle 32-3HV and toward the
surface 33.
[0060] The spray material M' includes the water vapor 12 and the
heated water 15H as they just exit the respective ports 21-3V and
21-3H in FIG. 3(g), or the respective ports 21-3WV and 21-3H in
FIG. 2(g). The spray material M flows from the main port 21-3VH
(FIG. 2(f)) or 21-3HV (FIG. 2(g)) into the chamber 23 and toward
the surface 33, and is in the form of water vapor 12 and water mist
14.
[0061] It may be understood that the device 40-3 and the ports
21-3WV and 21-3H (of FIG. 2(f)), and the ports 21-3V and 21-3H (of
FIG. 2(g), define another system for converting water 15 input to
the heater 51. The conversion is to the respective water vapor 12
and water mist 14. The nozzles 32-3VH and 32-3HV with the
respective main ports 21-3VH and 21-3HV spray (and direct) the
water vapor 12 and water mist 14 to the surface 33.
[0062] FIGS. 3 through 7 are graphs illustrating various
relationships of parameters by which the removing operation may be
controlled to increase efficiency, for example, and optimize
treatment of the target article 24. For ease of description, the
parameters are referred herein to as "water supply parameters" to
avoid reference to "parameters relating to both water vapor 12 and
water mist 14", for example. It is to be understood that references
herein to "water supply parameters" means and includes "parameters
relating to both water vapor 12 and water mist 14". The parameters
are defined and controlled as a way of controlling the removal
operations to minimize, for example, the time required to remove
all of the above-defined unnecessary objects from the surface 33 of
the target article 24. This time is also referred to herein as
"peeling-off time", or "resist peeling-off time". Thus, it may be
understood, that in one example of the present invention, this
removal may be referred to as "peeling-off", and a process of
peeling-off the unnecessary object may be said to result in a
"peeling-off state" of the surface 33, which state represents the
amount (zero to 100%) of the unnecessary object that has been
removed. In the context of FIGS. 3 through 7, for example, a 100%
peeling-off state, for example, refers to a complete removal of the
unnecessary objects from the surface 33. Such minimization of time
may also, for example, reduce the amount of DIW 15 required for a
particular removal operation.
[0063] The water supply parameters may include at least (Parameter
1) a weight ratio of the water vapor 12 to the water mist 14
supplied to the surface 33 of the target article 24 to be
processed. This weight ratio of Parameter 1 is in terms of a
numerator, which is the weight of the water vapor 12 in a unit
volume of the spray material M at the surface 33 of the target
article 24. This weight ratio of Parameter 1 is also in terms of a
denominator, which is the combined (or total) weight of the water
vapor 12 and the water mist 14 in such unit volume of the spray
material M. The ratio of such numerator and denominator is
expressed as a percentage (%) and may be expressed as the weight
ratio % of Parameter 1, or simply the "weight ratio".
[0064] The second parameter (Parameter 2) is a temperature Ts of
such surface 33 to be processed. During the removal operations
according to the present invention (e.g., while the spray material
M is being directed onto the surface 33 of the target article 24),
the temperature Ts may be measured, for example, by an infra red
sensor system 61-1 such as that shown in FIG. 2(a), or a similar
system 61-3 shown in FIG. 2(e). The system 61 may output a visual
indication of the temperature Ts, or another form of indication, to
permit control of the temperature Ts, and may be connected to the
controller 43.
[0065] The third parameter (Parameter 3), is the distance H between
the port 21 of the nozzle device 31 and the surface 33 to be
processed (see H in FIGS. 2(a) and 2(e).
[0066] To illustrate the Parameters, reference is made to FIGS. 3
through 7, which are graphs based on data taken by the inventors in
testing of the operation of the present invention. The graphs
illustrate various relationships of the Parameters by which the
removing operation may be controlled, i.e., may be performed under
the above-described controlled conditions. In each case represented
by these graphs, a device such as the intermediate device 40-1
shown in FIG. 2(a) was used to supply heated DIW 15. A rate of the
supply of the DIW 15 was about 400 cc/min. Apparatus similar to
apparatus 22-1 shown in FIG. 2(a) was used to provide both water
mist 14 and water vapor 12 directed in the chamber 23 toward and
onto the surface 33. Data relating to FIG. 3 is shown below in
table 1. Peeling-off of the unnecessary objects resulted from the
tests. These objects were in the form of the various resists listed
below in Table 2.
1TABLE 1 Peeled-Off % vs. Surface Temperature Data of FIG. 3
Temperature .degree. C. resist A resist B resist C resist D Resist
E Average 40 0 0 0 0 0 0 50 0 0 0 0 0 0 60 3 3 30 0 20 11.2 70 5 5
50 0 50 22 80 7 45 100 20 70 48.4 90 10 60 100 30 80 56 100 60 100
100 50 100 82 110 100 100 100 100 100 100 120 78 85 100 20 100 76.6
130 50 30 30 10 70 38 140 5 5 5 5 10 6 150 0 0 0 0 0 0 160 0 0 0 0
0 0
[0067]
2TABLE 2 Identification of Resists In FIG. 3 resist A i-line TOKYO
OUKA, iP3250 film thickness 0.985 .mu.m + Plasma Etching resist B
i-line TOKYO OUKA, POSITIVE FILM THICKNESS 1.4 .mu.m resist C
i-line FFA POSITIVE FILM THICKNESS 1.0 .mu.m resist D KrF FIJI FILM
ORIN, POSITIVE FILM THICKNESS 0.56 .mu.m R & P resist E i-line
TOKYO OUKA, iP3250 FILM THICKNESS 0.985 .mu.m R & P
[0068]
3TABLE 3 Peeled-Off % vs. Distance H Data for FIG. 4 Distance (mm)
resist A resist B Resist C resist D resist E Average 5 95 80 100 60
90 85 10 100 100 100 100 100 100 15 90 100 100 100 90 96 20 60 70
50 20 50 50 25 20 45 20 5 20 22 30 0 0 0 0 0 0 40 0 0 0 0 0 0 50 0
0 0 0 0 0 60 0 0 0 0 0 0 70 0 0 0 0 0 0 80 0 0 0 0 0 0 90 0 0 0 0 0
0 100 0 0 0 0 0 0 110 120 130
[0069]
4TABLE 4 Distance H vs. Surface Temperature Data for FIG. 6
Distance (mm) Temperature (.degree. C.) 5 104-150 10 98-121 15
87-104 20 87-94 30 50-87
[0070] FIG. 3 is a graph showing a relationship between the
peeling-off state (i.e., % removed) of a resist film at the various
temperatures Ts when the spray material M is supplied from the
nozzle device, such as the device 31-1. As shown in FIG. 3, the
range of temperature Ts was 40 to 160.degree. C. In order to obtain
the data (Table 1), standard values were used to establish
operating conditions in addition to the temperature Ts of the
target surface 33 and measurements of the peeling-off state.
Exemplary data include (A) and (B) below. (A) is a 50% weight ratio
between water vapor 12 and water mist 14 on the surface 33 (i.e.,
one part water vapor 12 and one part water mist 14). (B) is a
distance H of 10 mm provided between the port 21 and the surface
33. Further, one curve is shown for each of the five resist types
shown in Table 2. The duration of each removal operation for each
of the resists was the same.
[0071] From FIG. 3 it can be easily understood that in the removal
process of the present invention, exemplified by removal of these
resists, the peeling-off state varies depending on the temperature
Ts. In general, FIG. 3 shows that a preferred surface 33
temperature Ts would be in a range of above about 50 to below about
150.degree. C. A more preferred range of temperature Ts is more
than about 70 to about 130.degree. C., because all of the resists
are removed to some extent in this exemplary range. A still more
preferable range of the temperature Ts is from about 100 to about
120.degree. C. in view of the unexpectedly high (three resists
100%, and average 82%) removal of the resists. Such ranges,
especially the range in which the removal of the resist is
unexpectedly high, are examples of optimum removal results, i.e.,
optimum treatment of the target article 24.
[0072] For these resists, the most preferred temperature Ts is
110.degree. C. at which all of the resists were 100% removed
(peeled-off). The results presented in FIG. 3 may be attributed to
hardening or alteration of the resist, which increases with
increasing temperature Ts, making removal of the resist at the
higher temperature Ts more difficult. On the other hand, permeation
of the water vapor 12 through the resist appears to be resisted due
to a slow diffusion speed when the surface temperature Ts is too
low.
[0073] The curves of FIG. 3 show that the temperature Ts of the
surface 33 is one of the important parameters to control in the
removal operations according to the present invention. Further, a
high peeling-off effect (improved removal rate) can be reliably
obtained by setting and controlling the temperature Ts within such
ranges, such that it is possible to realize a highly efficient
removal of unnecessary objects, such as resist films.
[0074] An aspect of the present invention is also that the
temperature Ts of the surface 33 greatly depends on the temperature
of the spray material M and on the clearance H between the port 21
and the surface 33. One way, then, of controlling the temperature
Ts of the surface 33, is by operation of the controller 43 to
regulate the operation of the intermediate device 40 (including the
various embodiments of the device 40) as described above so as to
achieve a desired value of the temperature Ts by control of the
temperature of the water mist 14, and of the water 15, and of the
water vapor 12, as the case may be. Also, the desired value of the
temperature Ts may be set in the apparatus 22 by causing the
controller 43 to set a pressure in the chamber 23 to a value that
achieves a desired temperature Ts.
[0075] Referring to FIG. 4, a graph is shown illustrating
relationships between the resist film peeling-off state (i.e., %
removed) of various resist films, and the clearance H (FIG. 2(a))
between the port 21 of the nozzle 32 and the surface 33 of the
target article 24. In order to obtain the data on which FIG. 4 is
based, standard values were used to establish operating conditions
in addition to the clearance H and measurements of the peeling-off
state. Exemplary data include (A) and (C) below. (A) is a 50%
weight ratio between water vapor 12 and water mist 14 on the
surface 33 (i.e., one part water vapor 12 and one part water mist
14). (C) is that the temperatures of the water vapor 12 and of the
water mist 14 were set so that the temperature Ts of the surface 33
was about 100.degree. C. (which FIG. 3 shows is a most preferred
temperature Ts). Further, one curve is shown for each of the five
resist types shown in Table 2. The above Table 3 identifies data on
which the graph of FIG. 4 is based. The duration of each removal
operation for each of the resists was the same.
[0076] From the curves of FIG. 4 it can be easily understood that
in the removal process of the present invention, exemplified by
these resists, the peeling-off state varies depending on the
distance H between the port 21 of the nozzle 31 and the surface 33
of the target article 24. As shown in FIG. 4, to peel-off the
resist, a preferred value of such clearance H is in a range of
about 5 mm to below 30 mm. Further, FIG. 4 shows that a more
preferred value of such clearance H is in a range of about 10 to 15
mm. While not shown by FIG. 4, in the case of carrying out only
wafer cleaning (i.e., without the more difficult peeling-off), a
range of 30 mm to 100 mm is also possible. Such ranges, especially
the range in which the removal of the resist is 100% or very close
to 100%, are examples of optimum removal results, i.e., optimum
treatment of the target article 24.
[0077] It has also been determined that by changing the clearance
H, the temperature Ts and a hitting force of the spray material M
(of the water mist 14 and the water vapor 12) against the surface
33 can be adjusted. Accordingly, the Parameters of the removal
operations of the present invention may be defined and values of
the Parameters set according to the type of resist, for example,
and those operations may be effectively carried out irrespective of
the type of resist and process that are used.
[0078] FIG. 4 omits data corresponding to clearances H lower than 5
mm. A curve of actually measured data in this range would gently
converge to a zero point (peeling-off state 0%, clearance 0 mm).
However, for such values of clearance H lower than 5 mm, the force
of the spray material M on the surface 33 becomes very strong.
Thus, although an apparatus 22 may be designed, and is within the
scope of the present invention, in which the clearance H is up to 2
mm to 3 mm, from the viewpoint of resist peeling-off, the apparatus
22 having a very small value of the clearance H would be less
practical than the peeling-off obtained corresponding to the
clearance H in the range from about 5 mm to about 15 mm, for
example.
[0079] Referring to FIG. 5, a graph is shown illustrating
relationships between the time (in seconds) required to attain a
peeling-off of 100% of the resist from the surface 33, and the
weight ratio (%) of the water vapor 12 to water mist 14 in spray
material M directed onto the surface 33 of the target article 24.
In order to obtain the data on which FIG. 5 is based, standard
values were used to establish operating conditions in addition to
the weight ratio and the measurements of the peeling-off state.
Exemplary data include (C) and (D) below. (C) is the temperature T
of the water vapor 12 and of the water mist 14, which were set so
that the temperature Ts of the surface 33 was about 100.degree. C.
(which FIG. 3 shows is a most preferred temperature Ts). In the
apparatus 22, the controller 43 would set (C). (D) is that the
clearance H was about 10 mm. In the apparatus 22, the controller 43
would set H, as by moving the table 26 up or down relative to the
nozzle 32. Also, various experiments were conducted for many
samples of the target article 24, and the results were used to
calculate averaged data.
[0080] From the curve of FIG. 5 it can be easily understood that in
the removal process of the present invention, the rate of the
peeling-off state varies depending on the weight ratio. Based on
FIG. 5, it appears that one may expect a gentle upwardly open
curved fluctuation to occur, such that the resist peeling-off time
(or duration to peel-off 100% of the resist) has a minimum at one
value of the weight ratio, and such duration increases from that
minimum value for both lower and greater values of the weight
ratio. The relative value of the minimum appears to be unexpectedly
low compared to the values away from the minimum. Additionally, it
can be easily understood from FIG. 5 that when the weight ratio is
20% or lower, or alternatively 80% or higher (in which the weight
ratio was found to be very uneven), the rate of resist peeling-off
is greatly lowered, and extends the removal processing time (or
duration). Such ranges close to such minimum, especially the weight
ratio corresponding to the minimum in which the time taken for 100%
removal of the resist is unexpectedly low, are examples of optimum
removal results, i.e., optimum treatment of the target article 24.
Further, it may be understood that the exemplary values of the
resist peeling-off time (below 60 sec.) at the weight ratio of 50%
are said to be substantially less than the values of the resist
peeling-off time corresponding to those weight ratios below 20% and
above 80%, for example. In the context of the exemplary data in
FIG. 5, for example, the weight ratios that result in substantially
less resist peeling-off time may be said to be from about 35% to
about 55%. For other wafers and resists and articles 24, etc., the
weight ration % may be different, but FIG. 5 indicates that there
is a range of values corresponding to substantially less resist
peeling-off time.
[0081] This result (illustrating decreased rates of removal) is
attributed to the belief that when one of the water vapor 12 and
the water mist 14 becomes extremely small (corresponding to high or
low weight ratios), there is insufficient water vapor 12 or water
mist 14, as the case may be, to provide the function of the lower
percentage part of the spray material M. The function of each of
the water vapor 12 and the water mist 14 will be described
later.
[0082] Referring to FIG. 6, a bar graph is shown illustrating
relationships between the clearance H (as defined above) and the
temperature Ts (as defined above). In order to obtain the data on
which FIG. 6 is based (which is set forth in the above Table 4),
standard values were used to establish operating conditions in
addition to the clearance H and the temperature Ts. Exemplary data
include (A), which is a 50% weight ratio between water vapor 12 and
water mist 14 on the surface 33 (i.e., one part water vapor 12 and
one part water mist 14). The duration of each removal operation for
each of the resists was the same. Also, various experiments were
conducted for many samples.
[0083] From the curves of FIG. 6 it can be easily understood that
in the removal process of the present invention, the temperature Ts
varies in direct proportion to variation of the clearance H.
[0084] FIG. 7(a) shows a graph related to the apparatus and method
of the present invention. A relationship is shown in FIG. 7(a)
between spraying pressure (in Mpa) of the spray material M (which
pressure may be another parameter), and the weight ratio of the
spray material M. The spraying pressure is of the spray material M
(i.e., of the mixture of the water vapor 12 and the water mist 14)
directed against the resist as the unnecessary object 24 on the
surface 33 of the target article 26. In order to obtain the data on
which FIG. 7(a) is based, standard values were used to establish
operating conditions in addition to the pressure and the weight
ratios. Exemplary data include provision of standard atmospheric
pressure in the chamber 23. From the curve of FIG. 7(a) it can be
easily understood that in the removal process of the present
invention, the spraying pressure varies in direct proportion to
variation of the weight ratio.
[0085] FIG. 7(b) shows another graph related to the apparatus and
method of the present invention. A relationship is shown between
vapor pressure (in Atm.) of the water vapor 14, and temperature in
the chamber 23. FIG. 7(b) shows that as the mixture of water vapor
12 and water mist 14 are directed out of the nozzle 32 and have a
normal (i.e., 1 Atm.) pressure, the weight ratio increases.
[0086] FIG. 8 depicts a flow chart 80 describing operations of a
method of the present invention for supplying water (in the form of
the spray material M) to perform removal treatment, such as
cleaning of, peeling-off from, or working of, the target article
24. The method moves to an operation 82 of defining certain
parameters for the supply of water vapor 12 and water mist 14 to
the surface 33 of the target article 24 to be processed. In the
defining operation 82, the water supply parameters are defined to
include one or more of the following, which have been described
above: (1) weight ratio of the water vapor 12 to the water mist 14
directed onto the surface 33 of the target article 24 to be
processed, (2) the temperature Ts of such surface 33 to be
processed, and (3) the distance H between a water blowing port 21
and such surface 33 to be processed. Also, parameters other than
the above-described parameters (1) to (3) may be provided. For
example, additional parameters may be (4) a spraying pressure (FIG.
7(a)) or a speed of the spray material M through the nozzle 32, and
(5) a total amount of water vapor 12 and water mist 14 (i.e., the
denominator of the weight ratio) may be defined.
[0087] The method moves to an operation 84 of supplying the water
vapor 12 and the water mist 14 under the control of one or more of
those defined water supply parameters. In the controlled supplying
under operation 84, the one or more of the water supply
parameter(s) are set to proper values so that the removal
operations may be conducted under the controlled conditions for
optimizing the treatment of the target article 24. These proper
values relate to the characteristics of the particular unnecessary
objects that may be on the surface 33 of the target article 24 that
is to be processed. For example, according to characteristics of
that unnecessary object on the surface 33, and as described above
with respect to the resists (for example) that are the subject of
FIGS. 3 through 7, an exemplary weight ratio of the water vapor 12
to the water mist 14 directed onto the surface 33 of the target
article 24 may be near or at the minimum value of the weight ratio
shown (e.g.) in FIG. 5. Alternatively, Parameter 1 may be selected
to correspond to data for the particular unnecessary object in the
manner in which FIG. 5 shows a range of weight ratios of 20% or
higher, or alternatively 80% or lower. Such ranges close to such
minimum value, especially the weight ratio corresponding to the
minimum in which the time taken for 100% removal of the resist is
unexpectedly low, are examples of optimum removal results, and may
be set, or selected. The removal operations conducted with the set,
or selected, parameter(s) are said to be conducted under controlled
parameters. Based on the above descriptions of the controller 43,
and of the valves (e.g., 53 and 58), and DIW supply 44, generator
45, and heater 51, which may be controlled by the controller 43,
for example, it may be understood that values of these parameters
may be set. The operation 84 may also be performed as described
with respect to FIG. 2(a) in which water 15 is supplied, and then
converted by the nozzle 32-1 to the water vapor 12 and the water
mist 14. In a similar manner to that described above, there may be
a further operation, or a further aspect of operation 84, in which
the value of one or more of the parameters may be set. In the
method of flow chart 80, the operation 84 may select, or set, the
value of one or more of the parameters, or of each of the
parameters, as described above with respect to FIGS. 3-7(a) and
7(b). In this manner, the peeling-off time resulting from the
value, or from the values, may be substantially less than the
peeling-off time that other- wise would result from the use of a
value that is out of the most preferred range or ranges of the
various values. In this regard, the term "substantially" is used as
defined below.
[0088] The method moves to operation 86, in which a determination
is made as to whether the peeling-off state is one of a desired
percent removal, such as 100% removal. If "yes", the removal
operation is DONE. If "no", in an operation 88 the removal
operation continues via a loop 90 that returns to operation 84. The
removal operation continues to be conducted under controlled
conditions of operation 84 until another determination is made
according to operation 86.
[0089] As another example of setting, or selecting, a parameter
according to characteristics of that unnecessary object on the
surface 33, and as described above with respect to the resists (for
example) that are the subject of FIGS. 3 through 7, an exemplary
temperature Ts may be provided for the surface 33. For the
particular unnecessary object on that surface 33, and based on the
curves shown in FIG. 3, a preferred temperature Ts of that surface
33 would correspond to the range in FIG. 3 of above about
50.degree. C. to below about 150.degree. C. In a similar manner,
for that unnecessary object on that surface 33, a more preferred
range of the temperature Ts could be provided, and may correspond
to the about 70.degree. C. to about 130.degree. C. of FIG. 3,
because all of the resists are removed to some extent in that
exemplary range. Similar provision of the temperature Ts could be
made corresponding to the still more preferable range of the
temperature Ts in FIG. 3 of from about 100.degree. C. to about
120.degree. C. in view of the unexpectedly high (three resists
100%, and average 82%) removal of the resists. Such ranges,
especially the range in which the removal of the resists is
unexpectedly high, are examples of optimum removal results.
[0090] In review, controlling of the temperature Ts of the surface
33 may be by operation of the controller 43 to regulate the
operation of the intermediate device 40 (including the various
embodiments of the device 40) as described above so as to achieve a
desired value of the temperature Ts. Such control may be by
operation of the controller 43 to control the appropriate one or
more of the temperature of the water mist 14, of the water 15, and
of the water vapor 12, as the case may be. Also, the desired value
of the temperature Ts may be set in the apparatus 22 by causing the
controller 43 to set a pressure in the chamber 23 to a value that
achieves a desired temperature Ts.
[0091] In a similar manner, the graph of FIG. 4 may be used to
provide a clearance H for the removal operation. The delta H in
FIG. 2(a) represents the table having the adjustment, which under
the control of the controller 43, may vary the clearance H.
[0092] Regarding manufacturing of a target article 24, such as a
semiconductor device, in a peeling-off-type removal process using a
spray material M containing a mixture of water vapor 12 and water
mist 14, by changing the weight ratio of the water vapor 12 to the
water mist 14, it is possible to remove unnecessary objects, such
as various kinds of organic materials, resists and polymers. In
other words, according to the configuration of the target article
and the unnecessary objects, a removal process according to the
present invention can be identified corresponding, for example, to
such factors as the adhesiveness between the unnecessary object to
be peeled-off and the wafer of the semiconductor device.
[0093] In a target article 24 including a resist film stuck on a
wafer, taken as an example of a target article 24 to be processed
according to the present invention, the resist film is firmly
adhered onto the wafer, forms a solid film layer, and normally has
a thickness in a range of 500 to 800 nm. In this resist film on the
wafer, by using the water supply apparatus 22 and the method of the
present invention, removal of the resist film after ion
implantation is executed very effectively.
[0094] Also using the present invention, the removal operation on
the target article 24 is not limited to removal of the resist film
as an unnecessary object, in that another example of a removable
unnecessary object may be a polymer residue. This polymer residue
is generated as a reactive produce during dry etching. By using the
present invention, such a polymer residue can be removed very
effectively. Further, the resist film and the polymer residue can
be simultaneously removed by using the present invention, although
each may be separately removed depending on the situation.
[0095] Furthermore, in the water supply apparatus 22 and the method
of the present invention, the water vapor 12 and the water mist 14
are supplied, and mixed to form the spray material M, and this
spray material M is directed to the target article 24 by being
directly sprayed (ejected) to the surface 33 to be processed. The
water vapor 12 of the spray material M (of the water vapor 12 and
the water mist 14) is effective for changing quality of the resist
film or the like by permeation by gas. The water mist 14 is
effective for peeling-off the resist film or the like by the action
of the water particles 18.
[0096] Another example of the target article 24 is a base polymer
structure for forming a resist film in semiconductor device
manufacturing. This structure has valence and hydrogen bonding and,
by the inclusion in the spray material M of the high-temperature
water vapor 12, physical changes such as softening and expansion
occur in the resist film. In addition, the water vapor 12 has a
high degree of permeability into the resist, causing physical
property changes such as swelling, separation and coagulation to
occur to cause a quality change in the chemical structure. Thus, by
the high-temperature water vapor 12, the resist film, softened by
hydration/swelling, is peeled-off because of weakened adhesive
force with the wafer. An injection force, or a jetting-out force,
of the spray material M from the nozzle device 31 (which supplies
the water vapor 12 and the water mist 14 to the target article 24),
becomes very effective for peeling-off the swelled resist from the
surface 33 of the wafer substrate.
[0097] The water supply apparatus 22 and the method of the present
invention have been described mainly with reference to the example
of removing the resist film and the polymer residue as unnecessary
objects in semiconductor electronic device manufacturing. However,
an application range of the present invention is not limited to
such an example, but includes machining and precision surface
treatment fields in other electronic devices or the like. The water
supply apparatus 22 and the water supply method of the present
invention are very effective in the chemical cleaning and
peeling-off field, including for cleaning after substrate
processing by way of chemical mechanical polishing (CMP), dry
etching surface cleaning, fine circuit cleaning, fine circuit
forming mask cleaning and the like.
[0098] As described above, according to the water supply apparatus
22 and the method of the present invention, by setting the
parameters for establishing water supply and the other conditions,
and by specifying the above-described proper ranges of the
parameters, the spray material M of water vapor 12 and water mist
14 can be properly and effectively sprayed and directed to the
target article 24. Thus, it is possible to achieve a highly
efficient water supply apparatus and method, having a high
capability of peeling-off and removing unnecessary objects such as
a resist film. Such high capability may be evidenced by decreased
time to achieve 100% peeling-off (see FIG. 5, for example). Also,
according to the present invention, only super-pure water present
in a natural environment need be used, or water 15 compatible with
such super-pure water (e.g., DIW), which water 15 has high
compatibility with the environment and yet results in production of
the spray material M capable of permeating into the surface 24 of
the unnecessary object (e.g., the target organic material),
weakening adhesiveness to help peeling-off. Moreover, according to
the present invention, removal process control is facilitated to
provide high stability, many additional prior art devices are
rendered unnecessary for the removal operations of the present
invention, which facilitates simple designing of the apparatus 22
of the present invention.
[0099] Further, as described with respect to the context of the
exemplary data in FIG. 5, for example, the weight ratios that
result in substantially less resist peeling-off time may be said to
be from about 35% to about 55%. It is to be understood that for
other wafers and resists and articles 24, etc., the particular
weight ratio % having substantially less resist peeling-off time
may be different. In a similar manner, the relationships of
peeling-off percent in FIGS. 3 and 4 may have a respective
temperature Ts or clearance H that result in substantially 100%
peeling-off. Those exemplary substantially 100% peeling-off may be
said to be from about 100 degrees C. to about 105 degrees C., for
example (FIG. 3), and about 10 mm to about 15 mm in FIG. 4. It is
to be understood that the term "substantially" as used with respect
to peeling-off time or peeling-off % means at least a difference of
15%.
[0100] It should be appreciated that although in one embodiment the
wafer carrier is aligned with the polishing pad using a gimbal, the
embodiments of the present invention are not limited to CMP systems
including that implement a gimbal. Additionally, although the
embodiments of the present invention is shown to be implemented in
CMP systems including linear polishing pads, in a different
embodiment, any appropriate polishing table may be implemented
(e.g., rotary, etc.) Furthermore, while the embodiments of the
present invention have been described in terms of a CMP process,
the complimentary sensors are not limited to a CMP process. For
example, the sensors can be used within any semiconductor process
that removes or deposits a layer or film on a substrate, such as
etch and deposition processes. The invention has been described
herein in terms of several exemplary embodiments. Other embodiments
of the invention will be apparent to those skilled in the art from
consideration of the specification and practice of the invention.
The embodiments and preferred features described above should be
considered exemplary, with the invention being defined by the
appended claims.
* * * * *