U.S. patent application number 10/359115 was filed with the patent office on 2004-04-22 for etching method and apparatus.
This patent application is currently assigned to SEIKO EPSON CORPORATION. Invention is credited to Koike, Takashi, Mori, Yoshiaki.
Application Number | 20040074870 10/359115 |
Document ID | / |
Family ID | 29404875 |
Filed Date | 2004-04-22 |
United States Patent
Application |
20040074870 |
Kind Code |
A1 |
Koike, Takashi ; et
al. |
April 22, 2004 |
Etching method and apparatus
Abstract
The invention intends to provide an etching method in which a
bank 12 is formed to a member to be processed 10, and thereby a
precise etching can be applied to a predetermined position, and
apparatus for the method. In a range outside of a predetermined
pattern of the member to be processed 10, a liquid repelling bank
12 is formed, and by use of a discharge head 16 a coating liquid 14
such as an etching liquid 15 is coated on an etching portion 18 of
the predetermined pattern. The etching portion 18 is rendered
lyophilic by treatment to improve the fixing properties of the
coating liquid 14, and the bank 12 is formed of a liquid repelling
film, and thereby the coating liquid 14 is inhibited from adhering
to the bank 12.
Inventors: |
Koike, Takashi; (Suwa-gun,
JP) ; Mori, Yoshiaki; (Suwa-gun, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
ALEXANDRIA
VA
22320
US
|
Assignee: |
SEIKO EPSON CORPORATION
Tokyo
JP
|
Family ID: |
29404875 |
Appl. No.: |
10/359115 |
Filed: |
February 6, 2003 |
Current U.S.
Class: |
216/83 ;
156/345.11 |
Current CPC
Class: |
C23F 1/02 20130101 |
Class at
Publication: |
216/083 ;
156/345.11 |
International
Class: |
C23F 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 6, 2002 |
JP |
2002-29322 |
Mar 1, 2002 |
JP |
2002-55673 |
Claims
What is claimed is:
1. An etching method characterized in that a bank is disposed in
the surroundings of an etching portion of a member to be processed,
an etching liquid is supplied into the bank by use of a liquid
discharge means, and thereby the etching portion is etched.
2. An etching method characterized in that a bank is disposed in
the surroundings of an etching portion of a member to be processed,
the surroundings of the etching portion are rendered a reactive gas
atmosphere, and a liquid capable of dissolving the reactive gas is
supplied into the bank by use of a liquid discharge means, and
thereby the etching portion is etched.
3. The etching method as set forth in claim 1 or 2 characterized in
that the etching portion is rendered lyophilic by treatment.
4. An etching method characterized in that an etching portion of a
member to be processed is rendered lyophilic by treatment, an
etching liquid is supplied to the etching portion by use of a
liquid discharge means, and thereby the etching portion is
etched.
5. An etching method characterized in that an etching portion of a
member to be processed is rendered lyophilic by treatment, the
surroundings of the etching portion are rendered a reactive gas
atmosphere, and a liquid capable of dissolving the reactive gas is
supplied to the etching portion by use of a liquid discharge means,
and thereby the etching portion is etched.
6. The etching method as set forth in any one of claim 1, 2, 4 or 5
characterized in that the etching is carried out with a reaction
product removed by suction.
7. The etching method as set forth in any one of claim 1, 2, 4 or 5
characterized in that the etching is carried out with the member to
be processed heated.
8. The etching method as set forth in claim 7 characterized in that
a member to be processed is heated to a temperature in the range of
30 to 60 degree centigrade.
9. The etching method as set forth in claim 1 or 2 characterized in
that the bank is rendered liquid repelling by treatment, or has a
characteristic of liquid repelling.
10. The etching method as set forth in any one of claim 1, 2, 4 or
5 characterized in that the bank is made of a fluororesin film.
11. An etching apparatus characterized in comprising a liquid
discharge means that supply an etching liquid to an etching portion
of a member to be processed, and a suction portion that sucks a
reaction product during the etching.
12. The etching apparatus as set forth in claim 11 characterized in
that the suction portion is combined with the liquid discharge
means.
13. An etching apparatus characterized in comprising a discharge
unit that includes a gas discharge portion that supplies a reactive
gas to an etching portion of a member to be processed, a liquid
discharge means that supply liquid capable of dissolving the
reactive gas to the etching portion, and a suction portion that is
disposed in the neighborhood of the gas discharge portion or the
liquid discharge portion and capable of sucking a reaction
product.
14. The etching apparatus as set forth in any one of claims 11
through 13 characterized in that the discharge unit is disposed
plurally.
15. The etching apparatus as set forth in any one of claims 11
through 13 characterized in that the discharge head is provided
with a heater.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to an etching method by which
part of a surface or a front surface of a member-to-be-processed is
removed, and an apparatus for the method. In particular, the
invention relates to an etching method, in which a bank is disposed
to a member-to-be-processed and thereby a coating region of a
coating liquid is selectively etched, and an apparatus for the
method.
[0003] 2. Description of Related Art
[0004] When elements and wiring patterns are formed on a
member-to-be-processed, such as a silicon wafer, photoresist is
coated on a surface of the member-to-be-processed, and patterned
according to photolithography, and with it as a mask, wet etching
with a coating liquid for use in etching, such as an HF aqueous
solution, or dry etching with plasma is applied. In such etching
methods, however, since a non-etching portion is protected by
forming a mask on a surface of a member-to-be-processed, many
materials are necessary to form the mask and many man-hours are
required, resulting in an increase in the cost.
[0005] In this connection, a method in which the etching is carried
out without forming a mask is disclosed in JP-A-2001-185526. In
this method, as a liquid discharge device, a discharge head
according to an ink-jet method is installed and controlled, thereby
an etching liquid is directly coated on an member-to-be-processed
according to a predetermined pattern, and thereby etching is
performed.
[0006] In the etching method where an etching liquid is directly
discharged on a surface of an member-to-be-processed, however, a
size of a liquid droplet to be discharged is determined according
to a shape of a discharge nozzle of the ink-jet system. That is,
since a surface area of a coating liquid, dropped on a surface of a
member-to-be-processed, is determined according to a nozzle shape,
it is impossible to etch a shape smaller than a discharge diameter
of a nozzle. Furthermore, a shape of thus etched pattern reflects
the shape of the liquid droplet, and becomes a round point or a
line or a plane made of successive round points. Thus, in the
etching in which a related art discharge nozzle is used, since a
liquid spreads according to the wettability and so on of the
member-to-be-processed, not only a shape smaller than the discharge
diameter but also a complicated shape and an edge are difficult to
form. Furthermore, there is a problem in that when an etching
liquid that is applied from a discharge nozzle scatters and sticks
to other portion than a portion-to-be-etched, the etching other
than a predetermined pattern is implemented. Still furthermore,
since a shape of the etching depends on an adhesion state of the
etching liquid, a shape accuracy becomes poor, resulting in
incapability of implementing fine etching.
[0007] Still furthermore, in a multi-layered film where a plurality
of films of the member-to-be-processed is laminated and in the case
of a plurality of films of the member-to be-processed being present
on the same plane, the etching is carried out by exchanging the
etching liquid according to the type of member-to-be-processed.
Accordingly, a similar process has to be repeated for each of all
types of the members-to-be-processed. As a result, the etching when
there are films of different members-to-be-processed takes many
man-hours.
[0008] Furthermore, when a reactive gas, a liquid capable of
dissolving the reactive gas, and a member-to-be-processed are
reacted to carry out the etching, in some cases, the reactive gas
remains in the surroundings of the member-to-be-processed.
Accordingly, there is a concern in that a residual reactive gas and
so on react with other materials and thereby generate unnecessary
reaction products, the reaction products may adhere onto a surface
of the member-to-be-processed and intervenes at an etching portion,
and thereby excellent patterning is disturbed.
SUMMARY OF THE INVENTION
[0009] The invention addresses or solves the above and/or other
problems, and provides an etching method in which in order to
enable to etch a necessary position of a member-to-be-processed, a
liquid repelling bank is formed or the wettability of a portion
other than an etching portion is enhanced, and thereby accurate
etching can be applied to a predetermined position, and an
apparatus for the method can be provided.
[0010] In order to address or overcome the above, an etching method
according to the invention is provided such that a bank is disposed
in the surroundings of an etching portion of a
member-to-be-processed, an etching liquid is supplied inside of the
bank by use of a liquid discharge device, and thereby the etching
portion is etched. According to the method, since only the etching
portion is coated with an etching liquid by use of the liquid
discharge device, the etching liquid can be inhibited from being
excessively used, and since a range of etching portion is limited
by use of the bank, accurate etching can be performed.
[0011] Furthermore, in the etching method according to the
invention, the etching portion can be etched by disposing a bank in
the surroundings of the etching portion of the
member-to-be-processed, by making the surroundings of the etching
portion an atmosphere of a reactive gas, and by supplying a liquid
capable of dissolving the reactive gas in the bank by use of the
liquid discharge device. Thus, in the etching that uses the
reactive gas and the liquid capable of dissolving the reactive gas,
the etching portion is provided with the bank, and thereby the
liquid is inhibited from diffusing. Still furthermore, the liquid
can be inhibited from being excessively used. Since a range of the
etching portion is limited by the bank, accurate etching can be
applied.
[0012] In addition, the etching portion can be rendered lyophilic
by treatment. Thus, when the liquid repelling treatment is applied
to the bank, and the lyophilic treatment is applied to the etching
portion, the fixing properties of the etching liquid or the liquid
can be enhanced.
[0013] Furthermore, the etching portion of the
member-to-be-processed is rendered lyophilic by treatment, the
etching liquid is fed to the etching portion by the liquid
discharge device, and thereby the etching portion can be etched.
Thereby, without forming the bank, the etching liquid can be fixed
to the etching portion, and thereby accurate etching can be carried
out.
[0014] Still furthermore, the etching portion of the
member-to-be-processed is rendered lyophilic by treatment, the
surroundings of the etching portion are made into an atmosphere of
the reactive gas, and the liquid capable of dissolving the reactive
gas is fed to the etching portion by use of the liquid discharge
device, and thereby the etching portion can be etched. Thereby,
without forming the bank, the etching liquid can be fixed to the
etching portion, and thereby accurate etching can be carried
out.
[0015] The above etching can be carried out while removing the
reaction product by suction. That is, since the reaction product in
the etching portion is rapidly removed, a disturbing of the etching
by a remaining reaction product can be inhibited, resulting in
excellent etching.
[0016] Furthermore, the etching can be applied to the
member-to-be-processed by heating. Thereby, the etching is promoted
in the speed, resulting in rapid and excellent etching.
[0017] Still furthermore, the heating of the member-to-be-processed
is carried out at a temperature in the range of 30 to 60 degree
centigrade. Thereby, the reaction with the member-to-be-processed
is promoted, and the liquid used in the etching can be inhibited
from vaporizing, resulting in rapid etching.
[0018] Furthermore, the bank is preferably rendered liquid
repelling by treatment, or is preferable to be liquid repelling.
Thus, when the bank is rendered liquid repelling by treatment, the
etching liquid can be inhibited from diffusing from the etching
portion, and precise etching can be performed.
[0019] Still furthermore, the bank is provided such that it is made
of a fluororesin film. Since the fluororesin is highly liquid
repelling to all liquids, it can be effectively used also when many
types of coating liquid are used.
[0020] An etching apparatus according to the invention includes: a
liquid discharge device that feeds etching liquid to an etching
portion of a member-to-be-processed, and a suction portion that
sucks reaction product during the etching. Since the discharge unit
includes the liquid discharge device and the suction portion, it
can supply the etching liquid and at the same time can remove the
reaction product generated during the etching.
[0021] Furthermore, the suction portion can be combined with the
liquid discharge device. When the suction device is thus disposed
integrally with the liquid discharge device, the reaction product
generated during the etching can be instantaneously removed.
[0022] Still furthermore, the etching apparatus according to the
invention may include a discharge unit that includes a gas
discharge portion that supplies a reactive gas to an etching
portion of a member-to-be-processed, a liquid discharge device that
supplies a liquid capable of dissolving the reactive gas to the
etching portion, and the suction portion that is disposed in the
neighborhood of the gas discharge portion or the liquid discharge
portion and is capable of sucking a reaction product. Thereby, in
addition to coating of the liquid, the reaction product generated
during the etching, and the reactive gas that has not contributed
to the etching, can be rapidly removed.
[0023] The discharge unit can be disposed plurally. Thereby, the
etching liquids or the reactive gases and the liquids corresponding
to a plurality of different films can be filled. Accordingly, the
etching to a plurality of films can be applied by only one
etching.
[0024] Furthermore, the discharge head can be provided with a
heater. Thereby, a reaction speed of a member-to-be-processed can
be enhanced, and a reaction product can be inhibited from
dewing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a schematic explaining etching in forming a bank
according to a first exemplary embodiment;
[0026] FIG. 2 is a schematic explaining etching due to wettability
control of a member-to be processed according to a second exemplary
embodiment;
[0027] FIG. 3 is a schematic explaining alteration of an etching
depth involving the first exemplary embodiment;
[0028] FIGS. 4 (1) and 4 (2) are schematics explaining etching in a
multi-layered film made of different types of film according to a
third exemplary embodiment, where FIG. 4 (1) is a schematic showing
a case where a member to be processed made of the multi-layered
film made of different types of film is etched, and FIG. 4 (2) is a
schematic showing a case where different types of film on the same
plane are etched;
[0029] FIGS. 5 (1) and 5 (2) are schematics explaining etching
according to a fourth exemplary embodiment where a reactive gas is
used, where FIG. 5 (1) is a schematic showing a case where the
multi-layered film made of different types of film is etched, and
FIG. 5 (2) is a schematic showing a case where the different types
of film on the same plane are etched;
[0030] FIG. 6 is a sectional view of a discharge unit provided with
a suction portion according to a fifth exemplary embodiment;
[0031] FIG. 7 is a sectional view of a discharge unit provided with
a suction portion according to a sixth exemplary embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0032] Exemplary embodiments of etching methods and apparatus
according to the invention are detailed below reference to the
drawings. Those described in the following are only part of
exemplary embodiments according to the invention, and the invention
is not restricted thereto.
[0033] When a member to be processed 10 is etched, in one method an
etching liquid 15, such as an HF aqueous solution, is directly
coated on the member to be processed 10, and in the other method in
an atmosphere where a reactive gas 22, such as a fluorine-based
gas, is present, a liquid capable of dissolving the reactive gas 22
is coated on the member to be processed 10, and the reactive gas
22, the liquid, and the member to be processed 10 are reacted, and
thereby the etching is performed. In the present exemplary
embodiment, unless particularly described, liquids capable of
dissolving the reactive gas, such as pure water or alcohol, and the
etching liquids, such as an HF aqueous solution, are collectively
described as a coating liquid 14.
[0034] An explanatory schematic of the etching according to a first
exemplary embodiment of the invention is shown in FIG. 1. First, a
member to be processed 10 is cleaned, and in order to etch the
member to be processed 10, a bank 12 is formed on a surface of the
member to be processed 10 in a predetermined pattern shape. The
bank 12 is coated with a coating liquid 14, or coated with pure
water in an atmosphere of a reactive gas 22. The bank 12 is liquid
repelling, and can inhibit the coating liquid 14 from scattering in
the surroundings of the pattern shape. Furthermore, a surface of
such bank 12 is formed of a film that is resistant to the coating
liquid 14 or the reactive gas 22 of the etching.
[0035] The bank 12 is formed as follows. First, a resist that is
liquid repelling to the coating liquid 14 is coated on a surface of
the member to be processed 10. This is exposed to a predetermined
pattern shape followed by developing, and thereby the bank 12 is
provided with a desired pattern shape. Since the bank 12 is made of
liquid repelling resist, it has a characteristic that repels the
coating liquid 14.
[0036] Alternatively, when a fluorine-based resin is coated on a
surface of the member to be processed 10, and followed by exposing
it to an electromagnetic wave, formation of a film of a composition
of the fluorine-based resin at a portion that is irradiated with
the electromagnetic wave can be inhibited. Accordingly, when the
electromagnetic wave is irradiated in the pattern shape, in the
liquid repelling bank 12, a pattern is formed. Since the
fluorine-based resin is highly liquid repelling to all types of
liquid, it is effective also when many types of coating liquids 14
are used. In exposing the fluorine-based resin like this, as the
electromagnetic wave light can be preferably used, and furthermore
the light is preferable to be ultra-violet light. Since the
ultra-violet light is inexpensive, safe, and easy to handle, the
simplification of fabricating process and the reduction of
fabricating cost can be accomplished.
[0037] Still alternatively, an ordinary resist is coated on a
surface of a member to be processed 10 followed by applying
patterning, the resist is fluorinated by treatment. Thereby, a
liquid repelling bank 12 is formed, and a pattern is formed on a
surface of the member to be processed 10.
[0038] Thus, when the liquid repelling bank 12 is formed, in the
case of the coating liquid 14 being coated running over the pattern
shape, since a runover portion is rendered the coating liquid 14
repelling by treatment, the coating liquid 14 outside of the
pattern shape can be inhibited from adhering. Furthermore, since
the coating liquid 14 repelled by the repelling bank 12 is
introduced into the pattern shape surrounded by the bank 12, and
followed by etching, the etching accuracy can be enhanced.
[0039] Furthermore, in the exemplary embodiment, the material of
the bank 12 is liquid repelling, or by later applying liquid
repelling treatment to the bank, the bank 12 is rendered liquid
repelling. However, by controlling a dropping amount of the etching
liquid, or by properly selecting an etching liquid that does not
etch the bank, without rendering the bank liquid repelling,
treatment can be applied. Still furthermore, when the pattern
accuracy is allowed to be relatively rough, the bank 12, which
forms a pattern formation region to which the etching liquid of a
processing liquid is supplied, may not be particularly rendered
liquid repelling by treatment, in this case a bank that is no
liquid repelling can be used.
[0040] On a surface of the member to be processed 10 thereon the
bank 12 is thus formed, in order to enhance the fixing properties
of the discharge liquid of the etching, the discharge liquid can be
rendered more lyophilic by treatment in a portion where the bank 12
is not formed. This can be realized by irradiating ultra-violet
light or by applying plasma treatment. That is, after the bank 12
is formed according to the above method, by irradiating
electromagnetic wave such as ultra-violet light on a region outside
of the bank 12 formation range, the film in the etching portion is
de-bonded and removed.
[0041] Since thereby the portion other than the bank 12 is rendered
more lyophilic, when the coating liquid 14 is coated on the member
to be processed 10 during the etching, the coating liquid 14 can
easily permeate the portion. Furthermore, since the bank 12 is
rendered liquid repelling by treatment, the coating liquid 14,
without adhering to the bank 12, is repelled and introduced in a
portion that is lyophilic. Accordingly, when a region outside of
the bank 12 formation range of the member to be processed 10 is
rendered more lyophilic by treatment, the coating liquid 14 can be
easily fixed.
[0042] In the above, in a substrate surface of the member to be
processed 10, the bank 12 is formed and thereby finer etching is
intended to obtain. That is, in the case of the coating liquid 14
being coated in a pattern shape on the member to be processed 10,
by forming the bank 12, the coating liquid 14 is inhibited from
running over a range of the desired pattern shape owing to the
surface tension of the liquid. Furthermore, since the bank 12 is
rendered liquid repelling by treatment, the coating liquid 14 is
repelled on the bank 12 and introduced in the lyophilic patterned
portion. That is, by forming the bank 12, a boundary of a coating
liquid range when the coating liquid 14 is coated is controlled.
Accordingly, by forming the bank, accurate etching can be
performed.
[0043] A second exemplary embodiment is shown in FIG. 2. In the
above method, the liquid repelling bank 12 is formed on a surface
of the member to be processed 10, however, a method, in which a
boundary of a coating region of the coating liquid 14 is controlled
without forming the bank 12, may be used. In this method, by
controlling the lyophilic properties on a surface of the member to
be processed 10, the coated coating liquid 14 is enhanced in the
fixing properties. For instance, after a mask is superposed on a
surface of the member to be processed 10, the UV light is
irradiated thereon, thus a range that is lyophilic can be formed.
In the mask, a body is made of a transparent glass substrate, and
on a portion corresponding to other than a pattern formation range
of the member to be processed 10, a light shielding film made of
chromium metal or the like is formed. Accordingly, when the UV
light is irradiated on the member to be processed 10 that is
covered by the mask, the UV light is irradiated only on a portion
where the light shielding film is not present. Thereby, the
patterned range of the member to be processed 10 is rendered
lyophilic, accordingly, the coating liquid 14 can be easily
introduced. Thus, a boundary of a region where the coating liquid
14 is coated can be controlled. In addition, other than the UV
light, when plasma treatment or the like is applied, the similar
effects can be attained.
[0044] As mentioned above, when the bank 12 is formed on a surface
of the member to be processed 10 and thereby the pattern formation
is applied, the etching high in the accuracy of the pattern shape
can be performed. That is, while in the etching according to the
related art method, when the member to be processed 10 is a SiO
substrate, a minimum pattern width is substantially 20 .mu.m,
however, in the etching according to the exemplary embodiment, a
minimum pattern width of 10 .mu.m can be formed. Accordingly, finer
device design can be performed.
[0045] As mentioned above, the bank 12 that controls the boundary
where the coating liquid 14 is coated is formed, the coating liquid
14 is discharged and coated, and thereby the member to be processed
10 is etched. According to the exemplary embodiment, in order to
coat the coating liquid 14 in a predetermined pattern formation
range, a liquid discharge head 16 is used as a liquid discharge
device. This is because when the liquid discharge head 16 is used
as coating apparatus, the coating liquid 14 can be coated only on
the etching portion 18. Accordingly, since there is no need of
coating the coating liquid 14 on an entire surface of the member to
be processed 10, the coating liquid 14 can be effectively saved.
Furthermore, since the bank 12 may be formed only in the
surroundings of a range where the coating liquid 14 is coated by
use of the liquid discharge head 16, the bank 12 can be formed in a
minimum range. Accordingly, the cost can be effectively reduced. In
addition, in the discharge nozzle 24 of the discharge head 16, the
surroundings of a nozzle opening portion is processed with a member
having the liquid repelling properties and the solution resistance.
That is, when the nozzle opening portion is formed with, for
instance, fluororesin or the like, the etching liquid and the
coating liquid 14, such as pure water, are inhibited from adhering.
Furthermore, it is preferable that a flow path of the etching
liquid, such as a nozzle interior of the liquid discharge head, is
rendered liquid resistant by treatment.
[0046] In the exemplary embodiment, as mentioned above, the coating
liquid 14 is coated by use of the liquid discharge head 16. By
controlling a discharge amount of the coating liquid 14 at the
liquid discharge head 16, an etching depth of the member to be
processed 10 in the same type of material can be altered. In FIG.
3, an explanatory schematic of the etching depth alteration
according to the first exemplary embodiment is shown.
[0047] That is, it is assumed that when the coating liquid 14 is
set at a slight amount in a liquid amount and coated on the member
to be processed 10, the etching depth of the member to be processed
10 is X, and when the coating liquid 14 is increased in its amount
and coated on the member to be processed 10, the etching depth can
be increased by Y. In the related art method, the coating liquid 14
is uniformly coated on the member to be processed 10, in order to
alter the etching depth, the etching has to be repeated several
times. However, in the exemplary embodiment, a coating range of the
coating liquid 14 is controlled by use of the liquid discharge head
16, thus the etching depth can be simply altered. Furthermore, in
this case, since the etching depth can be altered by the liquid
amount of the coating liquid 14, only by controlling the liquid
amount of the coating liquid 14 by use of the liquid discharge head
16, the etching depth of the member to be processed 10 can be
freely altered. That is, according to a position of the etching
portion, the depth can be altered at will.
[0048] In FIG. 4 (1), an explanatory schematic of etching according
to a third exemplary embodiment is shown.
[0049] When a plurality of the liquid discharge heads 16, such as
mentioned above, is mounted to etching apparatus, multiple liquid
discharge head can be obtained. This is effective when the etching
liquid 15, such as an HF aqueous solution, is directly coated on
the member to be processed 10 and thereby the etching is carried
out. In the respective liquid discharge heads 16 constituted in
multiple, the etching liquids 15 corresponding to the etchings of
different types of film are filled in, respectively. When the
respective etching liquids 15 are filled in the discharge heads 16
in advance, and the discharge nozzles 24 of the discharge heads 16
are controlled so as to successively switch the etching liquids 15,
the etching corresponding to a plurality of film qualities can be
performed at once.
[0050] A case where a member to be processed 10 that is made of a
multi-layered film and is subjected to the etching will be
considered, in which, for instance, two types or more of film 20
are formed into a multi-layer, that is, a film 20A is laminated on
top of a film 20B. In general, when such a member is etched, at
first, the etching is applied to the film 20A with the etching
liquid 15a to remove the film 20A, the top layer of the member to
be processed 10, and thereafter the coating liquid 14 is changed,
and the etching is applied to the film 20B with the etching liquid
15b.
[0051] According to the exemplary embodiment, since the discharge
head 16 is constituted into a multi-head and thereby different
types of etching liquid 15 are allowed to fill in corresponding
liquid discharge heads 16, the etching liquid 15a can be filled in
one liquid discharge head 16, and the etching liquid 15b can be
filled in the other liquid discharge head 16. The etching is
performed by coating the member to be processed 10 with the etching
liquid 15a at first, and thereafter by successively coating the
member to be processed 10 with the etching liquid 15b. That is,
when the etching liquid 15 is switched in accordance with the type
of the film 20, the member to be processed 10, in which two types
or more of film 20 are laminated, can be etched at once. Thus, in
the etching of the member to be processed 10 in which many types of
film 20 are laminated in a multilayer, when the liquid discharge
head 16 is constituted into a multi-head, in addition to saving
labor hours for exchanging the etching liquid 15 for each of the
film, labor hours to repeat the etching process from the beginning
for each of the film can be saved.
[0052] At this time, outside of the etching portion 18, the bank 12
is formed and the bank 12 is rendered liquid repelling by
treatment. Accordingly, there is no concern of the etching liquid
15, scattered from the liquid discharge head 16 during the coating,
adhering to the bank 12, and such an etching liquid 15 is repelled
from on the bank 12 and introduced into the lyophilic etching
portion 18. Accordingly, in the outside of the etching portion 18,
excessive etching action can be inhibited from applying, and
thereby the etching can be effectively applied.
[0053] Furthermore, in FIG. 4 (2), an exemplary modification of the
third exemplary embodiment is shown.
[0054] Such a multi-liquid discharge head 16 is also effective even
when different types of film are coated on same plane. When many
types of film like this are present on same plane, according to the
related art method, in accordance with the type of the film 20, the
etching liquid 15 is exchanged, that is, the etching is repeated
the number of the different types of film 20. However, according to
the exemplary embodiment, by switching the etching liquid 15 filled
in the multi-liquid discharge head 16 in accordance with each of
the film 20, the etching of different types of film can be
successively carried out. For instance, when two types of film have
been formed on same plane of the member to be processed 10,
according to the related art method, the etching liquid 15 has to
be exchanged for each of the film qualities to be etched, that is,
in total two times of the etching are necessary. However, according
to the exemplary embodiment, the respective etching liquids 15 are
filled in advance in the multi-liquid discharge head 16, and by
switching the etching liquid 15 for each of the film 20, two types
of film 20 can be etched at once in etching.
[0055] At this time, the outside of the etching portion 18 such as
the bank 12 is rendered liquid repelling by treatment. Accordingly,
since the etching liquid 15 is repelled, an unnecessary portion can
be inhibited from being etched. Furthermore, since a portion where
the bank 12 is not formed, that is, the etching portion 18 is
rendered lyophilic by treatment, the etching liquid 15 can rapidly
permeate and the etching can be performed instantaneously.
[0056] Furthermore, as mentioned above, when an amount of liquid of
the etching liquid 15, which is coated from the liquid discharge
head 16, is controlled, the etching depth can be controlled. Thus,
by controlling the amount of liquid for each of the liquid
discharge heads 16 and by switching the liquid discharge head 16
according to the film qualities, the member to be processed 10 can
be simply and rapidly etched.
[0057] In FIG. 5 (1), an explanatory schematic of the etching
according to the fourth exemplary embodiment is shown.
[0058] In the etching of the member to be processed 10, a case is
considered, in which a reactive gas 22 for use in the etching is
contained in an atmosphere, pure water or alcohol is coated in a
range of the etching, pure water or alcohol, the reactive gas 22,
and the member to be processed 10 are allowed to react, and thereby
the etching is carried out. When there is a plurality of different
types of film in the member to be processed 10, in order to etch
the different types of film, the reactive gas 22 has to be altered
for each of the film 20. At this time, the coating liquid 14, such
as pure water or alcohol, that is coated on the member to be
processed 10 is preferable to be the same type to save the labor
hours in exchanging the coating liquid 14.
[0059] When the different types of film are etched, a plurality of
reactive gases 22 is filled in advance in different containers, and
the type of the reactive gas 22 is switched according to the film
20 to be etched. Accordingly, the member to be processed 10 that
has different types of film can be successively etched by switching
the reactive gas 22. Such a reactive gas is discharged from the gas
discharge portion 17, and the coating liquid 14, such as pure
water, is discharged from the liquid discharge head 16 into the
atmosphere.
[0060] For instance, in the case of a member to be processed 10
that is constituted in a multi-layered film by laminating a film
20A and a film 20B that are different in the type, a reactive gas
22A and a reactive gas 22B are filled in advance. When the film 20A
in an upper layer portion is etched, the reactive gas 22a is
discharged into the atmosphere, the coating liquid 14 is coated in
a predetermined pattern shape, and thereby allowing reacting with
the member to be processed 10. After the film 20A coated on the
member to be processed 10 is removed, the reactive gas 22 is
switched to discharge the reactive gas 22B into the atmosphere, and
thereby the film 20B is etched.
[0061] In FIG. 5 (2), an exemplary modification of the etching
involving a fourth exemplary embodiment is shown.
[0062] Even when a film 20A and a film 20B that are different in
the type are formed on the same plane of the member to be processed
10, it is needless to say that by similarly switching the type of
the reactive gas 22, the etching can be successively carried
out.
[0063] As mentioned above, in the case of a multi-layered film in
which different types of processing members are laminated, and in
the case of different types of film being present on the same
plane, different types of the members to be processed 10 can be
successively etched, and thereby the etching process can be
shortened. At this time, by controlling a concentration of the
reactive gas 22, speed of the etching can be controlled. That is,
by setting the concentration of the reactive gas 22 in the
atmosphere at a higher value, the etching speed can be accelerated
or decelerated, that is, the etching speed can be controlled at
will.
[0064] Furthermore, when a processing member constituted of a
multi-layered film that has two or more types of film, or a member
to be processed 10 that has two types or more of film 20 on the
same plane, is etched, a mechanism that controls a liquid amount of
the coating liquid 14 such as pure water or alcohol, is provided to
the liquid discharge head 16. Since the etching depth can be
altered according to the liquid amount of the coating liquid 14, by
disposing the mechanism that controls the liquid amounts of these,
a device by which the etching depth can be altered can be designed.
Furthermore, it is effective also when through holes are formed in
the multi-layered substrate.
[0065] FIG. 6 is a sectional view showing a discharge unit provided
with a suction portion according to a fifth exemplary
embodiment.
[0066] When a material, such as fluororesin, whose decomposition is
accelerated by virtue of heat is used, a pattern formation time
period can be shortened by heating during the formation of the
pattern. When a heater 32 is disposed, in addition to allowing
enhancing the reaction speed between the coating liquid 14 and the
member to be processed 10, the reactive gas 22 that is used in the
etching, and unnecessary materials, such as water generated by the
reaction, can be rapidly vaporized. From this, by disposing the
heater 32, substantial dry etching can be realized.
[0067] In the case of HF gas is used as the reactive gas 22 in the
atmosphere in the etching of, for instance, a SiO.sub.2 film, when
the etching is performed at room temperature, in some cases, owing
to the dew condensation of HF, a chemical reaction is induced in
the SiO.sub.2 film in a portion other than a predetermined etching
portion 18, resulting in etching the portion other than the etching
portion 18. In this connection, the heater 32 is disposed and
controlled so as to heat to a temperature between a temperature at
which the HF gas dews with difficulty (30 degree centigrade or
more) and a temperature where a time period up to vaporization of
water is not too short (60 degree centigrade or less), thereby
inhibiting the HF gas from dewing, and thereby allowing etching the
etching portion 18. The reason to set the upper limit to a heating
temperature of the heater 32 is that, in the case of the coating
liquid 14 being pure water, when the heating temperature of the
member to be processed 10 exceeds 60 degree centigrade and becomes
higher, vaporization time of water-droplet becomes extremely short,
and furthermore the sheet separation may occur. Accordingly,
sufficient etching pattern cannot be obtained, resulting in
disturbing the etching. In order to inhibit this from occurring,
the heating temperature due to the heater 32 is restricted.
[0068] Furthermore, also by disposing the heater 32 to the
discharge head 16, the effect can be obtained. In the surroundings
of the liquid discharge head 16 and the gas discharge portion 17,
there are materials that tend to induce chemical reactions, such as
the etching liquid, and the coating liquid 14, such as pure water
or alcohol, and the reactive gas 22 in the atmosphere. In this
connection, in the surroundings thereof, the heater 32 is disposed,
thereby the reactive gas 22 and the reaction product are inhibited
from dewing or adhering, the vaporization thereof is accelerated,
and thereby an adverse affect on the member to be processed 10 is
inhibited. Thereby, the flying accuracy of the liquid droplet can
be maintained, resulting in excellent etching.
[0069] Still furthermore, in the surroundings of the liquid
discharge head 16, a suction portion 26 is disposed. FIG. 7 is a
sectional view of a discharge unit that is provided with a suction
portion according to a sixth exemplary embodiment. This is an
exemplary embodiment in a method in which the etching liquid 15
such as an HF aqueous solution is directly coated on the member to
be processed 10.
[0070] The liquid discharge head 16 is provided with a discharge
nozzle 24, and the etching liquid 15 is supplied under pressure
from a solution tank (not shown) to the discharge nozzle 24. In the
surroundings of the discharge nozzle 24, an annularly formed
suction exhaust path 28 is disposed, and with a suction portion 26
including such an ejector mechanism that makes use of air pressure,
the surroundings of the nozzle are sucked. The suction portion 26
and the discharge nozzle 24 are integrally formed, and the coating
of the etching liquid 15, and the suction of the atmosphere are
simultaneously carried out.
[0071] Furthermore, at a lower portion of the member to be
processed 10, a heater 32 is disposed, thereby in addition to
heating appropriately the member to be processed 10 to accelerate
the reaction of the etching, the reaction products and so on are
promoted to vaporize. In the surroundings of the discharge nozzle
24, such reaction products (vaporized water and so on) are present,
and when these adhere to the member to be processed 10 and the
discharge nozzle 24, a non-intentional reaction may be caused, and
the etching may be disturbed. Accordingly, by means of the suction
portion 26 disposed in the surroundings of the discharge nozzle 24,
unnecessary reaction products are removed.
[0072] Still furthermore, in an etching method, which fills
reactive gas 22 of the etching atmosphere sufficiently in the
surroundings of the member to be processed 10, and the coating
liquid 14, such as pure water, is coated, a sectional view of the
discharge head 16 portion when the suction portion 26 is provided
is shown.
[0073] From the discharge nozzle 24 of the liquid discharge head
16, the coating liquid 14, such as pure water, is coated, which is
supplied under pressure from a solution tank (not shown). In the
surroundings of the discharge nozzle 24, annular paths are doubly
disposed, an inside path supplying the reactive gas 22, an outside
path being a path to suck and exhaust the atmosphere of the
etching. At this time, in the neighborhood of the nozzle opening
portion, the inside reactive gas supply path 30 meets with a
discharge path of the coating liquid 14 coated from the nozzle
opening portion, and thereby the reactive gas 22 and the coating
liquid 14 are simultaneously supplied to the member to be processed
10. Furthermore, the suction and exhaust path 28 disposed on the
outside, provided with an annular suction opening disposed outside
of a discharge opening of the coating liquid 14 and the reactive
gas 22, sucks the atmosphere by use of an ejector mechanism (not
shown) that makes use of an air pressure. Thus, the coating liquid
14 path and the reactive gas 22 path and the suction and exhaustion
path 28 are integrally formed, and this is regarded as a suction
portion 26.
[0074] Under the member to be processed 10, the heater 32 is
disposed, and thereby the member to be processed 10 is
appropriately heated to accelerate the reaction of the etching, and
at the same time the reaction product is accelerated in vaporizing.
In the etching method that uses the reactive gas 22, the reactive
gas 22 that has not contributed to the reaction lingers
indefinitely in the atmosphere, in some cases, generates an
unintentional reaction product and has an adverse affect on the
etching, accordingly, has to be removed rapidly. In this
connection, the suction portion 26 rapidly removes the reaction
product, the reactive gas 22 that has not contributed to the
reaction, and vaporized water or gas from member to be processed
10.
[0075] In the etching in which the atmosphere is sucked by use of
the suction portion 26, the member to be processed 10 to which the
above bank 12 is formed can be used. Since the bank 12 is rendered
liquid repelling by treatment, there are no concerns of the
adherence of the coating liquid 14. Furthermore, since the etching
is performed in a portion where the bank 12 is not formed, when the
banks 12 are formed in advance with a small spacing, finer etching
can be performed. Accordingly, without depending on the dimension
of the liquid droplet of the coating liquid 14, the etching can be
performed at will. Still furthermore, since the coating liquid 14,
repelled by the liquid repelling bank 12, is rapidly introduced
into a lyophilic portion outside of a range of the bank 12, the
fixing properties of the coating liquid 14 can be enhanced,
resulting in the efficient etching.
[0076] Thus, according to the invention, since the liquid repelling
bank 12 is formed in the surroundings of the etching pattern shape,
a portion outside of a range of the pattern shape is treated so as
to repel the coating liquid 14. Accordingly, when the coating
liquid 14 is coated with running over portion that is the outside
of the pattern shape during the etching, the coating liquid 14 can
be inhibited from adhering in the outside of the pattern shape
range. Furthermore, the coating liquid 14, repelled by the liquid
repelling bank 12, is introduced inside of the pattern shape
surrounded by the bank 12, and the etching is carried out there,
accordingly, the etching accuracy can be enhanced.
[0077] Furthermore, since the liquid discharge head 16 and the
suction portion 26 are integrally formed, the reaction products or
the like scattered in the surroundings of the discharge nozzle 24
can be rapidly removed. Accordingly, materials detrimental to the
etching can be promptly removed, resulting in exhibiting an effect
in an enhancement in safety. Alternatively, the liquid discharge
head 16 and the suction portion can be separately configured.
[0078] Still furthermore, the etching methods and the apparatus
according to the invention can be applied to various technical
fields. For instance, the etching methods and the apparatus
according to the invention can be applied, for example, to the
pattern formation of silicon substrates, and the pattern formation
of hard masks when fabricating color filters and EL
(electro-luminescence) devices.
* * * * *