US20040074870A1

US20040074870A1 - Etching method and apparatus

Info

Publication number: US20040074870A1
Application number: US10/359,115
Authority: US
Inventors: Takashi Koike; Yoshiaki Mori
Original assignee: Seiko Epson Corp
Current assignee: Seiko Epson Corp
Priority date: 2002-02-06
Filing date: 2003-02-06
Publication date: 2004-04-22
Also published as: JP2003303803A; JP3932099B2

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.

Description

BACKGROUND OF THE INVENTION

1. Field of Invention

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.

2. Description of Related Art

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.

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.

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.

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

FIG. 1 is a schematic explaining etching in forming a bank according to a first exemplary embodiment; [0025]
FIG. 2 is a schematic explaining etching due to wettability control of a member-to be processed according to a second exemplary embodiment; [0026]
FIG. 3 is a schematic explaining alteration of an etching depth involving the first exemplary embodiment; [0027]
FIGS. [0028] 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;
FIGS. [0029] 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;
FIG. 6 is a sectional view of a discharge unit provided with a suction portion according to a fifth exemplary embodiment; [0030]
FIG. 7 is a sectional view of a discharge unit provided with a suction portion according to a sixth exemplary embodiment.[0031]

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

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. [0032]
When a member to be processed [0033] 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.
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 [0034] 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.
The [0035] 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.
Alternatively, when a fluorine-based resin is coated on a surface of the member to be processed [0036] 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.
Still alternatively, an ordinary resist is coated on a surface of a member to be processed [0037] 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.
Thus, when the [0038] 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.
Furthermore, in the exemplary embodiment, the material of the [0039] 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.
On a surface of the member to be processed [0040] 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.
Since thereby the portion other than the [0041] 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.
In the above, in a substrate surface of the member to be processed [0042] 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.
A second exemplary embodiment is shown in FIG. 2. In the above method, the [0043] 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.
As mentioned above, when the [0044] 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 μm, however, in the etching according to the exemplary embodiment, a minimum pattern width of 10 μm can be formed. Accordingly, finer device design can be performed.
As mentioned above, the [0045] 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.
In the exemplary embodiment, as mentioned above, the [0046] 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.
That is, it is assumed that when the [0047] 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.
In FIG. 4 ([0048] 1), an explanatory schematic of etching according to a third exemplary embodiment is shown.
When a plurality of the liquid discharge heads [0049] 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.
A case where a member to be processed [0050] 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 15 a 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 15 b.
According to the exemplary embodiment, since the [0051] 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 15 a can be filled in one liquid discharge head 16, and the etching liquid 15 b 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 15 a at first, and thereafter by successively coating the member to be processed 10 with the etching liquid 15 b. 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.
At this time, outside of the [0052] 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.
Furthermore, in FIG. 4 ([0053] 2), an exemplary modification of the third exemplary embodiment is shown.
Such a [0054] 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.
At this time, the outside of the [0055] 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.
Furthermore, as mentioned above, when an amount of liquid of the [0056] 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.
In FIG. 5 ([0057] 1), an explanatory schematic of the etching according to the fourth exemplary embodiment is shown.
In the etching of the member to be processed [0058] 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.
When the different types of film are etched, a plurality of [0059] 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.
For instance, in the case of a member to be processed [0060] 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 22 a 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.
In FIG. 5 ([0061] 2), an exemplary modification of the etching involving a fourth exemplary embodiment is shown.
Even when a [0062] 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.
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 [0063] 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.
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 [0064] 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.
FIG. 6 is a sectional view showing a discharge unit provided with a suction portion according to a fifth exemplary embodiment. [0065]
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 [0066] 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.
In the case of HF gas is used as the [0067] reactive gas 22 in the atmosphere in the etching of, for instance, a SiO₂film, 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 SiO₂film 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.
Furthermore, also by disposing the [0068] 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.
Still furthermore, in the surroundings of the [0069] 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.
The [0070] 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.
Furthermore, at a lower portion of the member to be processed [0071] 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.
Still furthermore, in an etching method, which fills [0072] 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.
From the [0073] 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.
Under the member to be processed [0074] 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.
In the etching in which the atmosphere is sucked by use of the [0075] 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.
Thus, according to the invention, since the [0076] 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.
Furthermore, since the [0077] 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.
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. [0078]

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.