JP2001310959A - Liquid etchant for wet-etching resin membrane and etching process using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid etchant for wet-etching which can provide a fine and uniform shape of etching for a short time, and to provide an etching process using it. SOLUTION: This liquid etchant for wet-etching of a resin membrane contains an electron donor in the liquid. And this etching process utilizes the liquid etchant in the wet-etching of the resin membrane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a resin film,
The present invention relates to a wet etching etchant capable of performing a clean and uniform shape etching in a short time, and an etching method using the same.

[0002]

2. Description of the Related Art Conventionally, a method of wet-etching a resin such as polyimide is disclosed in
No. 2206 discloses a method of performing wet etching using a solution containing hydrazine as a main component,
In addition, Japanese Patent Application Laid-Open No. Hei 5-301981 discloses an etching method using potassium hydroxide.

[0003]

However, in these wet etching methods, some materials require a very long time for etching, and in some cases, some materials cannot be wet-etched. For example, in order to wet-etch a polyimide (“UPILEX S” manufactured by Ube Industries, Ltd.), a polyamide (“MICRON” manufactured by Toray Industries, Inc.), a liquid crystal polymer (“VECTRA” manufactured by Polyplastics, Inc.) It took a very long time and was not realistic. Even in a material that can be easily wet-etched, unevenness often occurs in the etching. Particularly when etching is performed on a large area or continuously, it is difficult to etch the entire surface in a clean shape.

[0004] In general, the finer the pattern, the longer the etching time and the problem that the variation in etching becomes large. Furthermore, since the lateral direction and the thickness direction of the film to be etched are usually etched only to the same extent, it becomes difficult to etch a fine pattern as the film to be etched becomes thicker.

The present invention has been made in view of the background of the prior art.
An excellent etchant for wet etching of a resin film and an etching method using the same, which can provide an etching solution which is not only capable of etching in a short time but also has a clean and uniform etching shape, can be provided. Is what you do.

[0006]

The present invention employs the following means in order to solve the above-mentioned problems. That is, the etching solution for wet etching of the resin film of the present invention is characterized in that the etching solution contains an electron donor, and the etching method of the present invention uses such an etching solution. And wet etching of the resin film.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention has been made to solve the above-mentioned problem, that is, an etching solution for wet etching of a resin film capable of providing a product which can be etched in a short time and which has a clean and uniform etching shape. The present inventors have conducted intensive studies and have blended a specific agent called an electron donor into the etching solution. As a result, they have unexpectedly found that such a problem can be solved at once.

The present invention relates to a technique for etching a resin film by a wet etching method. The material of the resin film etched by the wet etching solution of the present invention is polyimide (for example, DuPont Toray). "Kapton" manufactured by Ube Industries, Ltd. "Upilex", Kanebuchi Chemical Industry Co., Ltd. "Apical", polyamide (for example, "Mictron" manufactured by Toray Industries, Inc.), PPS (polyphenylene sulfide) , PET (polyethylene terephthalate, for example, "Lumirror" manufactured by Toray Industries, Inc.), liquid crystal polymer (for example, "Siveras" manufactured by Toray Industries, Inc., Polyplastics Co., Ltd.)
Manufactured by Nippon Petrochemical Co., Ltd.) and the like, but are not limited thereto. Among these, a resin film made of polyimide, polyamide, or liquid crystal polymer is particularly preferably used.

The above resins may be used alone, or two or more kinds may be blended or bonded. Further, various additives may be added to the resin film. For example, a filler such as a flame retardant, a glass cloth, or the like can be used, but is not limited thereto.

[0010] Polyimides, polyamides, liquid crystal polymers and the like are generally known as resins which are hard to be etched. However, if the etching solution and the etching method of the present invention are used, these resins can be easily etched. There are benefits.

The above-mentioned resin film may be cut into an appropriate size or may be used in a strip shape. Further, another material may be used as the support, and may be attached to or adhered to the material. In this case, a metal, resin, glass, wood, paper, silicon wafer, or the like can be used as the support.

The thickness of the resin film is not particularly limited.
The thickness can be selected and used according to the application, but is preferably 500 μm or less, more preferably 100 μm or less.

The etching solution for wet etching of a resin film of the present invention (hereinafter simply referred to as an etching solution) has a characteristic constitutional requirement that it contains an electron donor. By including such an electron donor, the present inventors have investigated the surprising fact that the resin film to be etched is easily donated with electrons and the main chain of the polymer material in the resin film is easily cut. .

That is, when the main chain of the polymer material of the resin film to be etched is cut, the solubility of the resin film in the etchant increases, and the resin film can be easily etched. Such a main chain scission may occur only by the effect of the electron donor, but in most cases, the effect is synergistically exerted by a combination with other components of the etching solution.

The electron donor is not particularly limited as long as it has an effect of donating electrons to the resin film to be etched and having an effect of easily decomposing the resin film into an etching solution. Donors can be used. (1) Tetrathiafulvalene and its derivatives tetrathiafulvalene, bis (ethylenedithio) tetrathiafulvalene, bis (methylenedithio) tetrathiafulvalene, bis (trimethylenedithio) tetrathiafulvalene, 4,4′-dimethyltetrathiafulvalene And tetrakis (methylthio) tetrathiafulvalene, tetrakis (octadecylthio) tetrathiafulvalene, tetrakis (n-pentylthio) tetrathiafulvalene and the like. (2) Carbazole and derivatives thereof Carbazole, carbazole-N-carbonyl chloride, 3,6-diaminocarbazole, N-ethylcarbazole, N-ethylcarbazole-3-carboxyaldehyde, N-methylcarbazole, poly (N-vinylcarbazole) , 1,2,3,4-tetrahydrocarbazole, 1,3,6,8-tetranitrocarbazole, N-
Vinyl carbazole and the like. (3) anthracene and derivatives thereof anthracene, 1-anthracenecarboxylic acid, 2-anthracenecarboxylic acid, 9-anthracenecarboxylic acid,
1,8-anthracenedicarboxylic acid dimethyl ester,
9-anthraldehyde, 9,10-bis (chloromethyl) anthracene, 1,8-bis (hydroxymethyl)
Anthracene, 9,10-bis (phenylethynyl) anthracene, 9-bromoanthracene, 1-chloro-
9,10-bis (phenylethynyl) anthracene, 9
-Chloromethylanthracene, 9-cyanoanthracene, 9,10-dibromoanthracene, 9,10-dichloroanthracene, 9,10-dicyanoanthracene, 9,10-dihydroanthracene, 9,10-dimethylanthracene, 9,10- Diphenylanthracene, 2-hydroxymethylanthracene, 9-hydroxymethylanthracene, 9-methylanthracene, 9-
Phenylanthracene, 9-trifluoroacetylanthracene, 1,4,9,10-tetrahydroxyanthracene, 2,2,2-trifluoro-1- (9-anthryl) ethanol, 1,8,9-trihydroxyanthracene and the like . (4) Fluorene and derivatives thereof Fluorene, 2-acetamidofluorene, 2-acetylfluorene, 2-aminofluorene, 9-aminofluorene hydrochloride, 9,9'-bifluorenylidene, 9,9-bis (4-amino Phenyl) fluorene,
9,9-bis (4-hydroxyphenyl) fluorene,
9-bromofluorene, 9-bromo-9-phenylfluorene, 2,7-di (acetamido) fluorene, 2,
7-diaminofluorene, 2,7-diaminofluorene hydrochloride, 2,7-dinitrofluorene, 9-
Fluoreneacetic acid, fluorene-2-azo-2 ', 4'-
Dihydroxybenzene, fluorene-2-azo-2'-
Methyl-4'-hydroxybenzene, 2-fluorenecarboxaldehyde, 9-fluorenecarboxylic acid, 9-fluorenol, 9-fluorenylmethanol, 9-fluorenylmethylchloroformate, 9-fluorenylmethylsuccinimidyl Carbonate, 2-fluorofluorene, 2- (4′-methoxybenzylidene) aminofluorene, 2-nitrofluorene, 9-phenyl-9-fluorenol and the like. (5) Porphyrin and derivatives thereof Bilirubin, chlorophyll, hematoporphyrin, hematoporphyrin dihydrochloride, hemin, hemoglobin, protoporphyrin disodium salt, sodium copper chlorophyllin, tetrakis (4-carboxyphenyl) porphine, 5,10,15,20- Tetrakis (2,6-dichlorophenyl) porphine, tetraphenylchlorin, tetrachloroporphine and the like. (6) phthalocyanine, naphthalocyanine and derivatives thereof phthalocyanine, phthalocyanine chloroaluminum,
Phthalocyanine cobalt, phthalocyanine copper, phthalocyanine iron, phthalocyanine magnesium, phthalocyanine silver, phthalocyanine sodium, phthalocyanine tin, phthalocyanine zinc, 4-aminophthalonitrile,
4-n-butoxyphthalonitrile, 4,5-dichlorophthalonitrile, 2,3-dicyanohydroquinone, 4-hydroxyphthalonitrile, 3-nitrophthalonitrile,
4-nitrophthalonitrile, phthalonitrile, tetrafluorophthalonitrile 1,2,4,5-tetracyanobenzene and the like. (7) pyrene and derivatives thereof pyrene, 1-aminopyrene, 1,3-diaminopyrene,
1,6-diaminopyrene, 1,8-diaminopyrene, 1
-Methylpyrene, naphtho [2,3-α] pyrene, 1-nitropyrene, 1-pyrenemethanol and the like. (8) Others (eg, aromatic amines) 3,3 ′, 5,5′-tetra-tert-butyl-4,
4'-diphenoquinone, tetrakis (dimethylamino)
Ethylene, 3,3 ′, 5,5′-tetramethylbenzidine, N, N, N ′, N′-tetramethyl-1,4-phenylenediamine dihydrochloride, 2,4,7-trinitro-9-fluorenone, 2,4,7-trinitro-9
-Fluorenylidenemalononitrile, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, dimethylaniline, N-phenyldiethanolamine, p-phenylenediamine, tetramethyl-p-phenylenediamine Bis (trifluoromethyl) benzidine and the like.

Among such electron donors, preferably, tetrathiafulvalene, aromatic amines, carbazole,
At least one selected from fluorene and derivatives thereof can be used.

The amount of the electron donor added to the etching solution is not particularly limited, and may vary depending on other components contained in the etching solution, but is preferably 0.001 to 50% by weight of the total amount of the etching solution. And more preferably in the range of 0.005 to 50% by weight.

The etching solution of the present invention is preferably used in combination with other components such as an alkali metal compound and an amine compound, and further, water and alcohol, in addition to the electron donor. Other than these may be contained. The etchant is usually selected from a combination that forms a uniform solution, but may be non-uniform depending on the case.

As the amine compound used in the etching solution, for example, hydrazine, aqueous ammonia, aromatic amine, aliphatic amine and the like can be used.

As the aromatic amine, aniline, benzylamine, 1,2-phenylenediamine, 1,3-phenylenediamine, 1,4-phenylenediamine, m-xylylenediamine, p-xylylenediamine and the like are used. But not limited to these.

As the aliphatic amine, propylamine,
Hexylamine, ethylenediamine, triethylenediamine, hexamethylenediamine, propylenediamine,
Piperazine, piperidine, ethanolamine, n-propanolamine, isopropanolamine, n-butanolamine, diatanolamine, and the like can be used, but are not limited thereto.

Such an amine compound mainly serves to dissolve and extract a decomposition product of the resin film, but also contributes to decomposition depending on the resin film.

Next, potassium hydroxide, lithium hydroxide, sodium hydroxide and the like can be used as the alkali metal compound, but are not limited thereto. Such an alkali metal compound mainly serves to decompose the resin film, but in some cases, reacts with a resin film component to exhibit a function of improving solubility.

Next, the etching solution may contain at least one additive selected from alcohols, ureas, ketones, ethers and water.

The role of the additive is to dissolve the alkali metal compound or the amine compound, dissolve and extract the decomposition product of the resin film, and to homogenize the etching solution. And a role of dissolving and extracting a decomposition product of the resin film, and a role of improving the solubility by reacting with the resin film.

Examples of such additives include water, aromatic alcohols, aliphatic alcohols, urea, ketones, ethers, etc., specifically, phenol, benzyl alcohol, hydroquinone, methanol, ethanol, propanol, butanol, hexanol , Ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran,
Dioxane, diethyl ether, and the like can be used, but are not limited thereto.

[0027] Among these additives, it is preferable to use at least one selected from urea, alcohols and water. Urea has the role of enhancing the effect of the etching solution being anisotropically etched in the thickness direction of the resin film, and alcohols have the role of improving the uniformity of the etching solution.
Since water has a role of dissolving the alkali metal compound, it is preferable to add them. The amount of the additive contained in the entire etching solution is preferably 5 to 90% by weight.
This range is preferable from the viewpoint of suitably exhibiting the above-mentioned role.

Specific combinations of the components other than the electron donor in the etching solution include, for example, those having the following structures, but are not limited thereto.

For example, (1) Examples of the amine compound / alkali metal compound / alcohol include, as the amine compound, at least one selected from ethylenediamine, ethanolamine and benzylamine; A combination using at least one selected from potassium and sodium hydroxide and using at least one selected from ethanol and ethylene glycol as the alcohol can be employed.

In the above composition, instead of alcohol,
In the case of the example (2) using water, the same composition can be adopted except that ethylenediamine or ethanolamine is selected and used as the amine compound.

Next, in the case of example (3) in which a mixture of alcohol and water is used in place of alcohol in the above composition, ethylenediamine or ethanolamine is selected as the amine compound, and ethanol or ethylene is used as the alcohol. A combination using a mixture of at least one selected from glycol and glycerin in water can be employed.

Such a composition can be used as long as it not only decomposes the resin film so as to be easily dissolved, but also exerts the function of an etching solution for dissolving and extracting the resin film and its decomposition product. However, there is a preferable specific mixing ratio of each component in the etching solution.

For example, in the case of the above (1), the amine compound is 5 to 90% by weight of the whole etching solution, the alkali metal compound is 5 to 90% by weight of the whole etching solution, the alcohol is 5 to 90% by weight of the whole etching solution, The electron donor is preferably 0.005 to 50% by weight of the entire etching solution, and the other additives are preferably 0 to 80% by weight of the entire etching solution.

In the case of the above (2), the amine compound is 5 to 90% by weight of the whole etching solution, the alkali metal compound is 5 to 90% by weight of the whole etching solution, water is 5 to 90% by weight of the whole etching solution, It is preferable that the donor is 0.005 to 50% by weight of the whole etching solution, and the other additives are 0 to 80% by weight of the whole etching solution.

In the case of the above (3), the amine compound is 3-91% by weight of the whole etching solution, the alkali metal compound is 3-91% by weight of the whole etching solution, the alcohol is 3-91% by weight of the whole etching solution, and the water is water. Is 3-91% by weight of the whole etching solution, and the electron donor is 0.1-0.9% of the whole etching solution.
005 to 50% by weight, and the other additives are preferably 0 to 80% by weight of the whole etching solution.

In the present invention, it is also useful to use two or more types of etching solutions having different compositions. In this case, the composition change includes changing the electron donor addition amount, changing the electron donor, changing the amine compound addition amount, changing the amine compound, changing the alkali metal compound addition amount, changing the alkali metal compound, adding alcohol. The composition is changed by changing the amount, changing the alcohol, or the like, but is not limited thereto. By making these compositions different, the etching rate and the etching shape can be controlled.

The operating temperature of the etching solution greatly depends on the properties of the resin film to be etched.
Although it depends on the composition of the etching solution, it is preferably 10 to 1
A temperature condition of 00 ° C, more preferably 30 to 90 ° C, is employed. If the temperature is too high, the composition of the etchant changes during the etching. Conversely, if the temperature is too low, the etching efficiency tends to decrease.

As the etching method in the present invention,
Means such as a method of immersing a resin film to be etched in an etchant and a method of spraying an etchant on the resin film to be etched are preferably used.

In the case of spraying the etching solution, a method is generally used in which a spray nozzle is attached to the tip of the outlet, and the nozzle is sprayed by pressure.

Regarding the shape of the spray nozzle,
Although there is no particular limitation, for example, mini mist, round mist, air jet nozzle, descaling nozzle, QC nozzle, flat spray nozzle, wide flat nozzle, oblong nozzle, oblique flat nozzle, side spray of Kyoritsu Gosei Co., Ltd. Nozzle, full cone nozzle, square nozzle, elliptical nozzle, spiral nozzle, hollow cone nozzle,
A cleaning nozzle, a needle jet nozzle, or the like can be used, but is not limited thereto.

These nozzles may be used alone or in combination, or may be used in combination with different types of nozzles. The blowing pressure also varies greatly depending on the type and thickness of the resin film to be etched,
Preferably, it is used by spraying at a pressure of 9000 to 10000000 Pa. The jetting direction is preferably the thickness direction of the resin film to be etched, but in some cases, the jetting may be performed from the lateral direction or the oblique direction of the resin film.

In the etching method of the present invention, a method of applying ultrasonic waves during etching is also effective. A well-known vibrator is generally used for generating the ultrasonic waves. The frequency of these vibrators is not particularly limited, but is preferably 10
~ 1000 kHz, more preferably 20-600 kHz
It is good. These vibrators may be used alone or in combination. The direction of the ultrasonic wave is preferably the thickness direction of the film to be etched, but in some cases,
It is also conceivable to apply ultrasonic waves from a lateral direction or an oblique direction of the etching film.

In the etching method of the present invention, a method of irradiating ultraviolet rays during etching is also effective. The wavelength region of the ultraviolet light to be irradiated is not particularly limited, but is preferably from 200 to 500 nm. In this case, all the wavelengths of the light source may be irradiated, or only a specific wavelength of ultraviolet light may be irradiated using a filter or the like. For example, i-line (365 nm) and g-line (436 nm)
It is also possible to irradiate only ultraviolet rays, or conversely, to irradiate ultraviolet rays with only these wavelengths cut. Further, the wavelength of the ultraviolet light may be changed as appropriate during the etching.

As a lamp for irradiating ultraviolet rays,
For example, low-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, DEEP UV lamp, flash UV lamp,
A short arc metal halide lamp or the like can be used, but is not limited thereto.

The amount of ultraviolet light depends on the type and thickness of the film to be etched. However, considering the working time, it is preferable to use an amount of light such that the irradiation time is within 60 minutes at the maximum. A light amount in the range of 01 to 10 W / cm ² can be preferably employed, but is not limited thereto. The irradiation direction of the ultraviolet rays is preferably the thickness direction of the film to be etched, but depending on the case, the irradiation may be performed from the lateral direction or the oblique direction of the etched film, or may be performed from all directions.

Next, a series of procedures of the etching method according to the present invention will be described, but the present invention is not limited to this method.

First, an etching mask (a copper mask, a stainless steel mask, a resist mask, etc.) on the resin film is formed. As a mask forming method, a method of bonding to a resin film via an adhesive, a method of directly forming the mask on a resin film by sputtering or plating, a method of adhering to a resin film, and the like are preferably adopted. The mask may be patterned in advance, or may be patterned after being formed on the resin film. As the pattern formation of the mask, a photolithography method using a resist, a laser processing method, or the like is preferably employed.

After forming a patterned mask on the resin film, an etching solution containing an electron donor is supplied from the mask side to perform etching. When using two or more types of etching solutions, the same procedure is used. When the etching solution is switched, the etching solution may be supplied continuously. However, in some cases, the cleaning / drying step may be interposed with an appropriate cleaning solution (for example, water or alcohol).

As a method of supplying the etching solution, a method of dipping the resin film in the etching solution, a method of spraying with a spray, and the like can be used. At this time, ultraviolet irradiation or ultrasonic wave may be used in combination. Since the etching is usually performed only from one side, it is preferable to protect the side of the resin film where the mask is not formed with an appropriate material.
As such a protective material, copper, stainless steel, resist, or the like can be used.

The resin film treated by the etching method according to the present invention has through holes according to the etching pattern. By embedding a metal (such as copper or aluminum) for conduction in the through hole, a wiring board of two-layer wiring with conduction on both sides of the resin film can be obtained.

When the etching method according to the present invention is used, the hole for obtaining electrical continuity can be miniaturized in a good shape, so that the area that can be used for wiring increases accordingly.
As a result, a high-density wiring board can be formed.

Such a high-density wiring board can be used for a wide range of applications from a large substrate such as a motherboard for a personal computer to a small substrate such as an interposer for a CSP (chip scale package).

[0053]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Example 1 and Comparative Example 1 Polyimide film (“Kapton EN” manufactured by Du Pont-Toray Co., Ltd., “Upilex S” manufactured by Ube Industries, Ltd., “Apical NPI” manufactured by Kanebuchi Chemical Industry Co., Ltd.), polyamide film ( Toray Corp. "Mictron") and liquid crystal polymer film (Toray Corp. "Vectra CX") were each cut into a size of 50 mm x 50 mm.

These films were subjected to chromium sputtering, copper sputtering and plating to form copper foils having a thickness of 8 μm on both sides. Positive photoresist [Co., Ltd.] on both sides of this copper foil
"AZ P4000" from Hoechst] was applied using a spin coater, and dried on a hot plate at 100 ° C for 3 minutes.
Next, using a mask containing a circular pattern of 100 μmφ, one side was exposed to 300 mJ / cm ² with a g-line stepper, and developed using an AZ400K developer diluted 5 times with water for 3 minutes. 100μ suitable for
A circular pattern of mφ was formed.

Using the patterned photoresist as a copper etching mask, an aqueous solution of iron chloride at 40 ° C. as an etchant, pressure of 19 from a full cone nozzle (manufactured by Kyoritsu Alloys Co., Ltd .: model number 1 / 4KSFHS0665).
Etching was performed for 5 minutes while spraying at 6133 Pa.

After the etching of the copper, the photoresist is removed.
g, ethylene glycol 22 g, ethylene diamine 11
g, 34 g of water and 0.01 g of an electron donor, N-phenyldiethanolamine, in an amount of 70 g.
It was used by immersion for 10 minutes and etched.

Table 1 shows the results.

As Comparative Example 1, 33 g of potassium hydroxide was used.
22 g of ethylene glycol, 11 g of ethylene diamine,
Using an etching solution without electron donor composed of 34 g of water, the substrate was immersed at 70 ° C. for 10 minutes to perform etching.

Table 1 shows the results.

[0060]

[Table 1]

As is clear from Table 1, in Example 1,
In contrast to the anisotropically clean shape, which was etched uniformly, in Comparative Example 1, although the etching was performed, the etching was not uniform, the etching was discrete, and the etching rate was low. Some of the holes were not penetrated, and the anisotropy was small. Example 2 and Comparative Example 2 Using the same resin film as in Example 1, first, a copper mask was formed in the same manner as in Example 1. After forming the copper mask, an etching solution composed of 18 g of potassium hydroxide, 64 g of ethanolamine, 18 g of water, and 0.01 g of tetrathiafulvalene as an electron donor was used at 70 ° C. for 5 minutes so as to be immersed.
Etching was performed while irradiating 00 kHz ultrasonic waves.

Table 2 shows the results.

As Comparative Example 2, 18 g of potassium hydroxide was prepared.
Using an etching solution without electron donor composed of 64 g of ethanolamine and 18 g of water, immersion was performed at 70 ° C. for 5 minutes, and etching was performed while irradiating ultrasonic waves of 100 kHz.

Table 2 shows the results.

[0065]

[Table 2]

As is clear from Table 2, in Example 2,
In contrast to the anisotropically clean shape, which was etched uniformly, in Comparative Example 2, although the etching was performed, the etching was not uniform, the etching was performed separately, and the etching rate was low. Some of the holes were not penetrated, and the anisotropy was small. Example 3 and Comparative Example 3 First, a copper mask was formed in the same manner as in Example 1 using the same resin film as in Example 1. After forming the copper mask, sodium hydroxide 22 g, ethanolamine 11 g, ethanol 3
4 g, 33 g of water, and 0.01 g of 2,4,7-trinitro-9-fluorenone, an electron donor, were immersed at 60 ° C. for 5 minutes, and immersed in an ultra-high pressure mercury lamp (USHIO INC. )) While performing ultraviolet irradiation at 5 mW / cm ² .

Table 3 shows the results.

As Comparative Example 3, sodium hydroxide 22
g, ethanolamine 11 g, ethanol 34 g, water 3
3 g of an etching solution without an electron donor
Used ° C., it was immersed for 5 minutes and then etched while ultraviolet irradiation at 5 mW / cm ² using a Ushio Ltd. ultra-high pressure mercury lamp.

Table 3 shows the results.

[0070]

[Table 3]

As is clear from Table 3, in Example 3,
In contrast to the anisotropically clean shape, which was etched uniformly, in Comparative Example 3, although the etching was performed, the etching was not uniform, the etching was discrete, and the etching rate was low. Some of the holes were not penetrated, and the anisotropy was small. Example 4 and Comparative Example 4 First, a copper mask was formed in the same manner as in Example 1 using the same resin film as in Example 1. After forming the copper mask, 33 g of potassium hydroxide, 22 g of ethylene glycol, 11 g of ethylenediamine, 34 g of water, and 3,3 ′,
Using an etching solution composed of 0.01 g of 5,5′-tetramethylbenzidine at 70 ° C., a full cone nozzle (manufactured by Kyoritsu Gosei Seisakusho Co., Ltd .: model number 1 / 4KSFHS06)
From 65), etching was performed while jetting at a pressure of 196133 Pa for 5 minutes.

The results are as shown in Table 4. The etching was uniform and anisotropically clean.

As Comparative Example 4, 33 g of potassium hydroxide was used.
22 g of ethylene glycol, 11 g of ethylene diamine,
Using an etching solution without electron donor composed of 34 g of water at 70 ° C., a pressure of 1961 from a full cone nozzle (model number 1 / 4KSFHS0665) manufactured by Kyoritsu Gosei Seisakusho Co., Ltd.
Etching was performed while spraying at 33 Pa for 5 minutes.

The results are as shown in Table 4. Although the etching was completed, the etching was performed without uniformity, the holes were not penetrated due to the low etching rate, and the anisotropy was small.

[0075]

[Table 4]

Example 5 Using the same resin film as in Example 1, first, a copper mask was formed in the same manner as in Example 1. After forming the copper mask, an etching solution composed of 33 g of potassium hydroxide, 11 g of ethylenediamine, 22 g of ethylene glycol, 33 g of water, and 0.1 g of p-phenylenediamine as an electron donor was heated to 70 ° C.
And immersed for 5 minutes, irradiated with ultrasonic waves of 100 kHz, and etched while irradiating ultraviolet rays at 5 mW / cm ² using an ultra-high pressure mercury lamp (manufactured by Ushio Inc.).

The results are as shown in Table 5, and the etching was uniform and anisotropically clean. Example 6 Using the same resin film as in Example 1, first, a copper mask was formed in the same manner as in Example 1. After forming the copper mask, an etching solution composed of 20 g of potassium hydroxide, 60 g of ethanolamine, 20 g of water, and 0.01 g of 4,4′-bis (diethylaminobenzophenone) as an electron donor was heated to 70 ° C.
And immersed for 2 minutes, irradiated with ultrasonic waves of 38 kHz, and etched while irradiating ultraviolet rays at 5 mW / cm ² using an ultra-high pressure mercury lamp (manufactured by Ushio Inc.).

Next, an etching solution composed of 10 g of potassium hydroxide, 80 g of ethanolamine, 10 g of water and 0.01 g of tetramethyl-p-phenylenediamine as an electron donor was immersed for 2 minutes at 70 ° C. 38 kh
Etching was performed while irradiating an ultrasonic wave of z and irradiating ultraviolet rays at 5 mW / cm ² using an ultra-high pressure mercury lamp (manufactured by Ushio Inc.).

The results are as shown in Table 5, and the etching was uniform and anisotropically clean.

[0080]

[Table 5]

Example 7 Using the same resin film as in Example 1, first, a copper mask was formed in the same manner as in Example 1. After forming the copper mask, an etching solution composed of 5 g of sodium hydroxide, 85 g of ethanolamine, 10 g of water, and 0.005 g of tetrakis (dimethylamino) ethylene as an electron donor was immersed at 70 ° C. for 1 minute, and immersed at 38 kHz. Irradiate ultrasonic waves and use an ultra-high pressure mercury lamp (Ushio Inc.) for 1 mW
Etching was performed while irradiating ultraviolet rays at / cm ² .

Next, 15 g of potassium hydroxide, 70 g of ethanolamine, 15 g of water, 3,3 ',
Using an etching solution composed of 0.001 g of 5,5′-tetra-t-butyl-4,4′-diphenoquinone at 70 ° C., immersing for 1 minute, irradiating ultrasonic waves of 200 kHz, and applying an ultra-high pressure mercury lamp ( Etching was performed using a Ushio Electric Co., Ltd.) while irradiating with ultraviolet rays at 10 mW / cm ² .

Further, 10 g of potassium hydroxide, 10 g of ethylenediamine, 70 g of ethylene glycol, 10 g of water,
An etching solution containing 0.01 g of 4,4'-bis (dimethylaminobenzophenone) as an electron donor
It was immersed for 1 minute at 0 ° C., irradiated with ultrasonic waves of 100 kHz, and etched while irradiating ultraviolet rays at 5 mW / cm ² using an ultra-high pressure mercury lamp (manufactured by Ushio Inc.).

The results are as shown in Table 6. The etching was anisotropically clean and uniform.

[0085]

[Table 6]

Example 8 Etching was carried out in the same manner as in Example 7 except that an etchant in which 5% by weight of urea was added to each of the three types of resin film etchants used in Example 7 was used.

The results are as shown in Table 7. The etching was uniform and anisotropically clean. Example 9 Etching was performed in the same manner as in Example 7 except that an etching solution in which urea was added in an amount of 70% by weight to the three types of resin film etching solutions used in Example 7 was used.

The results are as shown in Table 7. The etching was uniform in an anisotropically clean shape and uniformly.

[0089]

[Table 7]

[0090]

According to the present invention, the wiring substrate can be etched in a short time, can be etched anisotropically, and can be etched in a uniform and uniform shape without variation.

Claims (13)

[Claims] 1. An etching solution for wet etching of a resin film, wherein the etching solution contains an electron donor. 2. The method according to claim 1, wherein the electron donor is tetrathiafulvalene,
2. The etching solution for wet etching of a resin film according to claim 1, wherein the etching solution is at least one selected from carbazole, fluorene, aromatic amine and derivatives thereof. 3. The method according to claim 1, wherein the electron donor is 0.1% of the total amount of the etching solution.
3. The etching solution for wet etching of a resin film according to claim 1, which is contained in an amount of 001 to 50% by weight. 4. The etching solution according to claim 1, wherein said etching solution contains an amine compound and an alkali metal compound.
The etching solution for wet etching of a resin film according to any one of the above. 5. The etching solution for wet etching of a resin film according to claim 4, wherein the amine compound and the alkali metal compound are each contained in the range of 5 to 90% by weight of the total amount of the etching solution. 6. The etching solution according to claim 1, wherein said etching solution contains at least one additive selected from alcohols, ketones, ethers, urea compounds and water.
5. The etching solution for wet etching of a resin film according to any one of 5. 7. The method according to claim 1, wherein the additive is 5 to 90% of the total amount of the etching solution.
7. The etching solution for wet etching of a resin film according to claim 6, which is contained in a range of weight%. 8. The etching solution for wet etching of a resin film according to claim 1, wherein said resin film is at least one selected from the group consisting of polyimide, polyamide and liquid crystal polymer. 9. An etching method comprising wet-etching a resin film using the etching solution for wet etching according to claim 1. 10. The etching method according to claim 9, wherein said etching solution is etched in two or more stages using two or more types of etching solutions having different compositions. 11. The etching method according to claim 9, wherein said etching is performed while irradiating ultraviolet rays. 12. The etching method according to claim 9, wherein said etching is performed while applying ultrasonic waves. 13. The etching method according to claim 9, wherein the etching is performed while spraying the etching solution.