JP2003124203A - Etchant composition for transparent conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an etchant in which an etching residue is not generated at all when a transparent conductive film undergoes wet etching and the wet etching can be conducted under gentle conditions while suppressing bubbling. SOLUTION: An aqueous solution containing oxalic acid, a surfactant of polyoxyalkylene alkylether sulfate and/or polyoxyalkylene alkylphenylether sulfate, and at least one kind selected from a group of polyoxyalkylene monoalkylether, polyoxyalkylene block polymer, polyoxyalkylene fatty acid ester and polyoxyalkylene denatured silicon oil is employed as an etchant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching agent composition used for wet etching a transparent conductive film such as ITO (hereinafter, indium tin oxide) used as a pixel electrode in a liquid crystal display or the like.

[0002]

2. Description of the Related Art Transparent conductive films such as ITO films are
It has been widely used in the field of electronic devices such as antistatic films, heat-reflecting films, photoelectric conversion elements and transparent electrodes of various flat panel displays. In particular, recently, with the spread of notebook PCs, small TVs, portable information terminals, and the like, the demand for liquid crystal displays (LCDs) is increasing. A transparent conductive film such as an ITO film is used as a display electrode of a pixel in the field of flat panel displays, and is formed by etching of photolithography. However, liquid crystal displays (LCD), especially TFT-LC
In the field of D, polycrystalline ITO has been conventionally used, but as the substrate size increases, it becomes difficult to make the polycrystalline ITO uniform. Further, as a method of forming the above-mentioned display electrode, a photoresist is applied on a transparent conductive film, and after exposure and development, an etching agent is used with the photoresist as a mask, and after etching, the remaining photoresist is peeled off. Formed.

Conventionally, as an etching agent for a transparent conductive film such as the above-mentioned polycrystalline ITO film, ferric chloride / hydrochloric acid aqueous solution, iodic acid aqueous solution, phosphoric acid aqueous solution, hydrochloric acid / nitric acid aqueous solution (aqua regia)
Etc. have been used. It is also difficult to pattern the wet etching agent for the transparent conductive film with high processing accuracy because corrosion of Al or the like occurs during patterning and selective etching proceeds from grain boundaries. For the above reasons, with the increase in the size of the substrate, the increase in the size of the TFT panel, the increase in the definition, the use of Al in the wiring, etc., there is an increasing demand for an etching agent that can be etched with high processing accuracy as a pixel display electrode. . In order to solve these problems, recently, a method of wet etching a transparent conductive film such as amorphous ITO with a weak acid, especially an oxalic acid aqueous solution has been proposed. However, there is a problem that an etching residue is generated when the transparent conductive film is wet-etched using an oxalic acid aqueous solution, and an etching agent that does not generate this etching residue is desired, and various additives should be added. A method for preventing the generation of etching residues is proposed, but the addition of an additive causes a problem that bubbles are generated when an etching agent is used, which is a problem in actual use.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to produce no etching residue when wet-etching a transparent conductive film such as amorphous ITO as described above in the prior art using an aqueous solution of oxalic acid. The purpose of the present invention is to provide an etching agent that does not perform wet etching under mild conditions and that suppresses the generation of bubbles.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the inventors of the present invention have found that oxalic acid and a polyoxyalkylene alkyl ether sulfate and / or a polyoxyethylene which is a surfactant are used. An aqueous solution containing an alkylene alkyl phenyl ether sulfate and at least one selected from the group consisting of polyoxyalkylene monoalkyl ethers, polyoxyalkylene block polymers, polyoxyalkylene fatty acid esters and polyoxyalkylene modified silicone oils is amorphous. Quality ITO
When wet-etching a transparent conductive film such as, it was found that wet-etching can be performed under mild conditions, generation of bubbles is suppressed, and no residue is generated at all, and it was completed based on such findings. .

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The concentration of oxalic acid used in the present invention is 0.01 to 10% by weight. If it is 0.01 wt% or less, the etching rate is slow, and if it is 10 wt% or more, the etching rate is not improved, which is not a good idea.

The polyoxyalkylene alkyl ether sulfate used in the present invention is represented by the general formula (1).

[0008]

Embedded image RO (CH ₂ CH ₂ O) nSO ₃ M (1) (wherein R is an alkyl group, n is an integer of 1 to 1000, and M is
Indicates ammonia, organic amine, quaternary ammonium, and alkali metal. )

Specifically, as the trade name, Emar 20
C (made by Kao), Hitenol 325D, Hitenol 12
(Daiichi Kogyo Seiyaku Co., Ltd.), Alscope AP-30, Alscope LE-240 (manufactured by Toho Kagaku), Sannor 605
N (made by Lion) and the like are preferably used.

Further, the polyoxyalkylene alkylphenyl ether sulfate used in the present invention is represented by the general formula (2).

[0011]

[Chemical 2] (However, R is an alkyl group, n is an integer of 1 to 1000, M
Indicates ammonia, organic amine, quaternary ammonium, and alkali metal. ) Specifically, commercially available high-tenol NE-05, high-tenol N-07 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Emal NC-35
(Made by Kao) etc. are used suitably. The polyoxyalkylene alkyl ether sulfate and the polyoxyalkylene alkyl phenyl ether sulfate may be used alone or in combination of two or more, and the preferable concentration is 0.0001 to 5% by weight. When it is 0.0001% by weight or less, a residue is generated during etching,
When it is 5% by weight or more, the etching rate of the transparent conductive film such as ITO decreases, which is not preferable.

The polyoxyalkylene monoalkyl ether used in the present invention is represented by the general formula (3).

[0013]

Embedded image RO (C ₃ H ₈ O) nH (3) (wherein R is an alkyl group and n is an integer of 1 to 1000).

Specifically, commercially available Pronal ST-
1, Pronal 66-P (above, manufactured by Toho Chemical Industry) Neugen ET-106A, Neugen ET-116B, Neugen DH0300, Neugen DL-0206 (above, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and the like are preferably used.

The polyoxyalkylene block polymer used in the present invention is represented by the general formula (4).

[0016]

Embedded image HO (CH2CH2O) l (CHCH3CH2O) m (CH2CH2O) nH (4) (wherein l, m and n are each an integer of 1 to 1000)

Specifically, commercially available Dovanox DH-1
509 (manufactured by Lion), Emulgen PP-150, Emulgen PP-250, Emulgen PP-290 (above,
Made by Kao), Epan 410, Epan 710, Epan 720
(The above are manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and the like are preferably used.

The polyoxyalkylene fatty acid ester used in the present invention is represented by the general formula (5).

[0019]

Embedded image RCOO (R ¹ O) nOCR (5) (wherein R is an alkyl group, R ¹ is an alkylene group, and n is
An integer from 1 to 1000. )

Specifically, commercially available CF-900 (manufactured by Hitachi Chemical Co., Ltd.), Neugen ES-99, Neugen ES-14.
9, Neugen ES-169 (above, manufactured by Dai-ichi Kogyo Seiyaku),
Kadenax GS-90, Kadenax SO-83, Lionon DT-600, Essoput 0/15, Essoput 60/15, Essoput 242/25 (made by Lion), Emanone 1112, Emanone 3130, Emanone 3170, Emanone 3299, Emanone 41.
10 (above, manufactured by Kao), nonion L-2, nonion S-
2, nonion O-2, nonion T-4 (above, manufactured by NOF CORPORATION), sorbon S-20, ANSTEX N-61, Emaruso 302, anti-curl 100 (above manufactured by Toho Chemical Industry) are preferably used. It

Further, the polyoxyalkylene-modified silicone oil used in the present invention is used as an antifoaming agent. Specifically, commercially available KS604, KS496
A, KS502, KS506, KS604 (produced by Shin-Etsu Chemical Co., Ltd.), YSA6406, YSA780 (above, produced by GE Toshiba Silicones) and the like are preferably used.

The above polyoxyalkylene monoalkyl ether, polyoxyalkylene block polymer, polyoxyalkylene fatty acid ester, and polyoxyalkylene-modified silicone oil may be used alone or in combination of two or more kinds. Medium 0.000
It is 1 to 20% by weight.

The above polyoxyalkylene monoalkyl ether, polyoxyalkylene block polymer, polyoxyalkylene fatty acid ester and polyoxyalkylene modified silicone oil have an addition concentration of 0.0001.
If it is at most% by weight, the defoaming effect will not be sufficient, and if it is at least 20% by weight, it will not be sufficiently dispersed or dissolved, which is not preferable.

In addition, a polyoxyalkylene alkyl ether and / or polyoxyalkylene alkyl phenyl ether, which is a surfactant, may be further added, if necessary, to improve the ability to remove the residue.

The polyoxyalkylene alkyl ether is represented by the following formula (6).

[0026]

Embedded image RO (CH ₂ CH ₂ O) nH (6) (wherein R is an alkyl group and n is an integer of 1 to 1000)

Specifically, commercially available Neugen ET-60
E, Neugen ET-120E, Neugen ET-180
E, Neugen ET-69, Neugen ET-83, Neugen ET-129, Neugen ET-170 (all manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Emulgen 104P, Emulgen 130.
K, Emulgen 210, Emulgen 306P, Emulgen 404, Emulgen 430, Emulgen 707 (all manufactured by Kao), Nonion E-206, Nonion E-21
5, Nonion P-210, Nonion S-215, Nonion K-220, Nonion T-208.5, Persoft N
K-100 (above, NOF Corporation), Noniolite AL-
5, Noniolite ACL-5, Noniolite AK-2
0, Noniolite AO-20, Noniolite AS-4
H, Noniolite AP-113, Noniolite AS-2
12 (above, Kyoeisha Oil and Fat Chemical Co., Ltd.), Nonal 10
6, Nonal 210, Nonal 430, Nonal C-1
8, Nonal L-9A (all manufactured by Toho Chemical Industry Co., Ltd.), Newcall 1004, Newcall 1100, Newcall 1203, Newcall 1105, Newcall 12
00, New Call 1310, New Call 1515,
Newcall 1545, Newcall 1620, Newcall 1820 (above, made by Nippon Emulsifier), Leocall S
C-30K, Leocor SC-120K, Leocor T
D-150K (above, made by Lion) etc. are mentioned.

The polyoxyalkylene alkylphenyl ether is represented by the general formula (7).

[0029]

[Chemical 7] (However, R is an alkyl group, n is an integer of 1 to 1000)

Specifically, commercially available Neugen EA16
7, Neugen EA170, Neugen EP120A, DK
S-elenone (above, Dai-ichi Kogyo Seiyaku), Emulgen 81
0, Emulgen 840S, Emulgen 903, Emulgen 909, Emulgen 913, Emulgen 985 (above, manufactured by Kao), Nonion NS-206, Nonion NS-
210, nonion NS-270 nonion HS-206,
Nonion HS-240 (above, NOF Corporation), Nonal CP-60 (Toho Chemical Industry), Surfynol PC,
Surfynol 104, Surfynol TG (above, manufactured by Nissin Chemical Industry Co., Ltd.), Newcol 561H, Newcall 568, Newcall 865 (above, manufactured by Nippon Emulsifier),
Liponox NC-10, Liponox NC-38, Liponox NC-600, Liponox BC-140
(Above, made by Lion) and the like.

The above polyoxyalkylene alkyl ether and polyoxyalkylene alkyl phenyl ether may be used alone or in combination of two or more kinds, and the preferable concentration is 0.0001 to 5% by weight in the total solution.

When the concentration of the above polyoxyalkylene alkyl ether or polyoxyalkylene alkyl phenyl ether is 0.0001% by weight or less, improvement in the ability to remove residues cannot be expected, and when it is 5% by weight or more, the transparent conductive film is The etching rate decreases, which is not preferable.

The use concentration of the present invention is from room temperature to 90 ° C., and the use time is about 1 to 30 minutes. Also,
The present invention is applicable to wet etching of various transparent conductive films such as amorphous ITO and IZO (indium-zinc oxide).
It is preferably used.

[0034]

【Example】

Example 1 In the substrate shown in FIG. 1, SiN2 which is an insulating film is formed on a glass substrate 1, amorphous ITO3 is further formed, and a resist 4 is applied on the amorphous ITO3. However, it is in a state after development. The substrate shown in FIG. 1 was mixed with 3.4 wt% of oxalic acid, 0.01 wt% of polyoxyalkylene alkyl ether sulfate (trade name: Hitenol 12, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.). 05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH03
00, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), a small tester is used for etching at 40 ° C. for 2 minutes to wash with water, and then a resist 4 is removed with a basic resist stripping solution.
Was peeled off, washed with water and dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 2 The substrate shown in FIG. 1 was treated with 3.4% by weight of oxalic acid and 0.
01% by weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 0.05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH03)
00, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is used to perform etching at 40 ° C. for 2 minutes with a small tester, followed by washing with water, and then peeling the resist with a basic resist stripping solution, followed by washing with water. And dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 3 The substrate shown in FIG. 1 was treated with 3.4% by weight of oxalic acid and 0.
01% by weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 0.5% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH030
0, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and then rinsed with a small tester at 40 ° C. for 2 minutes to wash with water, and then the resist is removed with a basic resist remover, followed by washing with water. And dried. SEM (electron microscope)
As a result of observing the surface with, the amorphous ITO was satisfactorily etched, and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 4 The substrate shown in FIG. 1 was treated with 3.4% by weight of oxalic acid and 0.
01 wt% of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Dai-ichi Kogyo Seiyaku) and 0.05 wt% of polyoxyalkylene block polymer (trade name: Epan 410, No. (Manufactured by Ichigo Seiyaku Co., Ltd.) is used, and a small tester is used to perform etching at 40 ° C. for 2 minutes to wash with water, and then the resist is removed with a basic resist remover, followed by washing with water and drying. did. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was well etched,
No residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 5 The substrate shown in FIG. 1 was treated with 3.4 wt.
01% by weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 0.05% by weight of polyoxyalkylene fatty acid ester (trade name: CF-900, Hitachi Chemical Co., Ltd.), using a cleaning solution that is an aqueous solution containing
After etching at 40 ° C for 2 minutes with a small tester and washing with water,
After removing the resist with a basic resist remover,
It was washed with water and dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 6 The substrate shown in FIG. 1 was treated with 3.4% by weight of oxalic acid and 0.
01% by weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 0.10% by weight of polyoxyalkylene-modified silicone oil (trade name: KS-604). , Manufactured by Shin-Etsu Chemical Co., Ltd.), and washed with water in a small tester at 40 ° C. for 2 minutes, washed with water, further stripped of the resist with a basic resist stripper, washed with water, and dried. did. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was well etched,
No residue was observed. In addition, almost no bubbles were observed on the small tester.

Comparative Example 1 The substrate shown in FIG. 1 was treated with 3.4% by weight of oxalic acid and 0.1.
01% by weight of polyoxyalkylene alkyl ether sulfate (trade name: Hitenol 12, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
Using a cleaning solution that is an aqueous solution containing, was etched with a small-sized tester at 40 ° C. for 2 minutes, washed with water, further stripped of the resist with a basic resist stripping solution, washed with water, and dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, a small amount of foam was observed on a small tester.

COMPARATIVE EXAMPLE 2 The substrate shown in FIG. 1 was washed with a cleaning solution which is an aqueous solution containing 3.4% by weight of oxalic acid in a small testing machine.
After etching at 2 ° C. for 2 minutes and washing with water, the resist was further stripped with a basic resist stripping solution, followed by washing with water and drying. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was well etched, but as shown in FIG. 3, many residues were observed. In addition, almost no bubbles were observed on the small tester.

Example 7 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate shown in FIG. 1 due to the difference in film forming conditions. % Oxalic acid,
0.01% by weight of polyoxyalkylene alkyl ether sulfate (trade name: Hitenol 12, manufactured by Dai-ichi Kogyo Seiyaku) and 0.05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH0300, No. 1) Manufactured by Ichigo Kogyo Co., Ltd. and 0.01% by weight of polyoxyalkylene alkyl ether (trade name: Neugen ET-60E,
(Daiichi Kogyo Seiyaku Co., Ltd.) using a washing solution that is an aqueous solution, and etching with a small tester at 40 ° C. for 2 minutes to wash with water, and then stripping the resist with a basic resist stripping solution, washing with water, and drying. did. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 8 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate of FIG. 1 due to the difference in film forming conditions. Oxalic acid, 0.01
% By weight of polyoxyalkylene alkyl ether sulfate (trade name: Hitenol 12, manufactured by Dai-ichi Kogyo Seiyaku),
0.05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH0300, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 0.01% by weight of polyoxyalkylene alkylphenyl ether (trade name: Neugen EP-120).
A, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was used to etch with a small tester at 40 ° C. for 2 minutes to wash with water, and then the resist was stripped with a basic resist stripper, followed by washing with water. Dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 9 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than that of the substrate of FIG. 1 due to the difference in film forming conditions is 3.4% by weight. Oxalic acid, 0.01
% By weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 0.05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH030
0, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. and 0.01% by weight of a polyoxyalkylene alkyl phenyl ether (trade name: Neugen EP-120A, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), which is a small aqueous solution and is used as a cleaning solution. After etching with a tester at 40 ° C. for 2 minutes and washing with water, the resist was further stripped with a basic resist stripping solution, followed by washing with water and drying. SEM
As a result of observing the surface with an (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Example 10 A substrate having the same structure as the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate shown in FIG. 1 due to the difference in film forming conditions is 3.4% by weight. Oxalic acid, 0.01
% By weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 0.5% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH0300,
Daiichi Kogyo Seiyaku Co., Ltd. and 0.01% by weight of polyoxyalkylene alkyl phenyl ether (trade name: Neugen E)
P-120A, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), a small tester is used to perform etching for 2 minutes at 40 ° C. for 2 minutes, and after rinsing with water, the resist is further stripped with a basic resist stripping solution, It was washed with water and dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was satisfactorily etched and no residue was observed. In addition, almost no bubbles were observed on the small tester.

Comparative Example 3 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate of FIG. 1 due to the difference in film forming conditions. Oxalic acid, 0.01
% By weight of polyoxyalkylene alkyl ether sulfate (trade name: Hitenol 12, manufactured by Dai-ichi Kogyo Seiyaku),
Etching is performed at 40 ° C. for 2 minutes with a small tester using a cleaning solution which is an aqueous solution containing 0.05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH0300, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). After washing with water, the resist was further stripped with a basic resist stripping solution, followed by washing with water and drying. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was etched well, but FIG.
A small amount of residue was observed as shown in FIG. In addition, almost no bubbles were observed on the small tester.

Comparative Example 4 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate of FIG. 1 due to the difference in film forming conditions. Oxalic acid, 0.01
% By weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 0.05% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH030
0, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and then rinsed with a small tester at 40 ° C. for 2 minutes to wash with water, and then the resist is removed with a basic resist remover, followed by washing with water. And dried. SEM (electron microscope)
As a result of observing the surface with, the amorphous ITO was well etched, but as shown in FIG. 2, a small amount of residue was observed. In addition, almost no bubbles were observed on the small tester.

Comparative Example 5 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate of FIG. 1 due to the difference in film forming conditions. Oxalic acid, 0.01
% By weight of polyoxyalkylene alkyl phenyl ether sulfate (trade name: Hitenol NE-05, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 0.5% by weight of polyoxyalkylene monoalkyl ether (trade name: Neugen DH0300,
(Manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), using a cleaning solution containing an aqueous solution containing 40 ° C. for 2 minutes with a small tester to wash with water, and then remove the resist with a basic resist remover, followed by washing with water, Dried. As a result of observing the surface with an SEM (electron microscope), the amorphous ITO was well etched, but a small amount of residue was observed as shown in FIG.
In addition, almost no bubbles were observed on the small tester.

Comparative Example 6 A substrate having a structure similar to that of the substrate shown in FIG. 1, but the residue after etching is more likely to remain than the substrate of FIG. 1 due to the difference in film forming conditions. Using a cleaning solution that is an aqueous solution containing oxalic acid, use a small tester at 40 ° C for 2
After etching for 1 minute and washing with water, the resist was further stripped with a basic resist stripping solution, followed by washing with water and drying. SE
As a result of observing the surface with M (electron microscope), amorphous ITO
Was etched well, but many residues were observed, as shown in FIG. In addition, almost no bubbles were observed on the small tester.

[0051]

EFFECTS OF THE INVENTION A transparent conductive film such as amorphous ITO can be wet-etched under mild conditions without generating etching residue at all, and generation of bubbles of a wet etching agent can be suppressed. .

[Brief description of drawings]

FIG. 1 shows a state after SiN that is an insulating film is formed on a glass substrate, amorphous ITO is further formed, a resist is applied on the amorphous ITO, and development is performed.

FIG. 2 shows a substrate having the same structure as the substrate shown in FIG. 1 after wet etching.

FIG. 3 shows a substrate having the same structure as the substrate shown in FIG. 1 after wet etching.

[Explanation of symbols]

1 glass substrate, 2 SiN, 3 amorphous ITO, 4 resist, 5 residue

Claims (2)

[Claims] 1. Oxalic acid, polyoxyalkylene alkyl ether sulfate and / or polyoxyalkylene alkyl phenyl ether sulfate, polyoxyalkylene monoalkyl ether, polyoxyalkylene block polymer, polyoxyalkylene fatty acid ester and polyoxy. An etchant composition for a transparent conductive film, which is an aqueous solution containing at least one selected from the group consisting of alkylene-modified silicone oil. 2. The etching agent composition for a transparent conductive film according to claim 1, wherein the transparent conductive film is indium tin oxide.