JPH09325484A - Sensitive component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensitive component which provides higher sensitivity and higher adhesion property than those obtained by a conventional method and can form a pattern which does not become overhang shape (reverse tapered shape) even if development is done excessively. SOLUTION: In a sensitive component made of resin, optical acid generation agent, cross linking agent, and solvent, main component of the resin is composed of copolymer having alcoholic hydroxyl group and/or carboxyl acid group. Moreover, a weight ratio of monomer having alcoholic hydroxyl group and/or carboxylic acid group of the copolymer is 5 to 50wt.%, and molecular weight of the copolymer is 3000 to 150000.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative photoresist, and it is highly sensitive and highly adherent in a manufacturing process of a liquid crystal display device including a so-called TFT and a manufacturing process of various etching parts, and even if excessive development is performed, The present invention relates to a photosensitive composition that does not have a hang shape (reverse taper shape).

[0002]

2. Description of the Related Art Conventionally, a photosensitive composition used in a manufacturing process of a liquid crystal display device including a TFT and various etching parts has a high sensitivity, a high adhesion to a substrate, a chemical resistance and a forward tapered shape. Generally, a negative resist is used because such characteristics as described above are required. To form a pattern using such a negative resist, usually, a resist solution is applied on a substrate, exposed through a photomask, and only the unexposed portion is dissolved in an alkali developing solution to develop, Form a pattern. As such a negative resist, a radical polymerization type photosensitive composition comprising a resin containing an acid group such as methacrylic acid, a polyfunctional acrylate such as pentaerythritol triacrylate and a photoradical generator such as 1-hydroxycyclohexyl phenyl ketone is used. And a negative photosensitive composition such as a photocrosslinking photosensitive composition composed of polyvinyl alcohol and dichromic acid or a cyclized rubber and a bisazide compound are mainly used.

However, when an attempt is made to form a pattern using such a negative-type photosensitive composition, low sensitivity,
If the development is carried out a little more excessively due to poor adhesion, it is difficult for light to penetrate to the lower part of the resist and the lower part of the pattern tends to have an overhang shape (inverse taper shape) due to insufficient crosslinking.

Further, when it is used in a process such as an etching part, since the metal plate is etched and the resist film is made to be a considerably thick film, insufficient cross-linking under the pattern tends to cause an overhang shape. Further, since the adhesiveness is not sufficiently high, there is a problem that the etching liquid enters from the pattern edge portion during etching, and the line width becomes thin, resulting in a defect.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of these problems. The problem is that the sensitivity and the adhesion are higher than those of the conventional methods and the development is excessive. Overhang shape (reverse taper shape)
Another object of the present invention is to provide a photosensitive composition capable of forming a pattern that does not become a pattern.

[0006]

In order to solve this problem, the present invention provides a photosensitive composition comprising a resin, a photo-acid generator, a cross-linking agent and a solvent, wherein the main component of the resin is an alcoholic hydroxyl group and And / or a photosensitive composition comprising a copolymer having a carboxylic acid group. The weight ratio of the monomer having an alcoholic hydroxyl group and / or a carboxylic acid group in the copolymer is 5 to 5
50 wt%, the molecular weight of the copolymer is 30
Provided is a photosensitive composition characterized in that it is from 0 to 150000.

[0007]

Embodiments of the present invention will be described below in detail. Examples of the monomer having an alcoholic hydroxyl group in the present invention include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4
2-hydroxybutyl (meth) acrylate, ε-caprolactone adduct of 2-hydroxyethyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, 2-hydroxyethyl (meth) acrylate
Basic acid anhydride and ethylene oxide adduct, phenylglycidyl ether adduct of (meth) acrylic acid,
Examples include glycidyl (meth) acrylate monocarboxylic acid adducts, allyl alcohol, and allyloxyethanol. In the copolymerization, if it is less than 5 wt%, the sensitivity is lowered, and if it exceeds 50 wt%, swelling and developability cannot be balanced. Therefore, it is preferable to use it in the range of 5 to 50 wt%.

Examples of the monomer having a carboxylic acid group in the present invention include acrylic acid, methacrylic acid, crotonic acid, vinylbenzoic acid, maleic acid, itaconic acid or (meth) acrylic acid caprolactone adduct, hydroxyalkyl ( Examples thereof include those obtained by adding an acid anhydride such as phthalic anhydride to (meth) acrylate. When this monomer is copolymerized, if it is less than 5 wt%, the sensitivity decreases,
If it exceeds 50 wt%, the developability cannot be balanced, so it is preferably used in the range of 5 to 50 wt%.

Other monomers copolymerizable with the monomer having an alcoholic hydroxyl group and / or a carboxylic acid group include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl ( Functionality of aliphatic (meth) acrylates such as (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, aromatic-containing (meth) acrylates such as benzyl (meth) acrylate, methoxyethyl (meth) acrylate, etc. Examples thereof include (meth) acrylate, styrene and styrene derivatives, N-substituted maleimides such as phenylmaleimide and cyclohexylmaleimide. This monomer may be one kind or more.

The molecular weight of the resin prepared as described above is
Preferably it is 3000-150,000, More preferably, it is 15000-80000. Molecular weight 300
When it is 0 or less, the sensitivity is insufficient, and when it is 150,000 or more, the developability decreases.

Examples of the cross-linking agent used in the present invention include melamines, guanamines and urea resins.

Specific examples of melamines include dimethylol melamine, trimethylol melamine, tetramethylol melamine, pentamethylol melamine and other partially methylolated melamine, hexamethylol melamine, and ethylol melamine or butyrol melamine alkylated products. There is. Examples of guanamines include acetoguanamine, benzoguanamine, partially methylolated benzoguanamine, tetramethylol benzoguanamine, and alkylated products of these methylol benzoguanamines. Examples of urea resins include dimethylol urea, methylated dimethylol urea, butylated dimethylol urea, dimethylol ethylene urea, dimethylol propylene urea, dimethylol triazone, dimethylolurone, and tetramethylol glyoxalurein. Such melamines, guanamines or urea resins are usually used in an amount of 1 to 50 relative to 100 parts by weight of the resin.
It is used in an amount of parts by weight, preferably 3 to 30 parts by weight.
If the amount of melamines or guanamines is less than 1 part by weight based on 100 parts by weight of the resin, the composition will not be sufficiently crosslinked, and it will be difficult to form pixels. If it exceeds 50 parts by weight, the alkali solubility will be high. If it is too much, the residual film rate will decrease after development.

The photoacid generator is a triazine compound,
Onium salt-based compounds can be mentioned. As a triazine-based compound, 2,4,6-tris (trichloromethyl)-
s-triazine, 2- (p-methoxystyryl) -4,
6-bis (trichloromethyl) -s-triazine, 2-
Phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-
Chlorophenyl) -4,6-bis (trichloromethyl)
-S-triazine, 2- (4'-methoxy-1'-naphthyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (N-isoamyloxycarbonylmethyl-
3'-carbazolyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (N- (2 "-methoxy-
1 "-methylethoxycarbonylmethyl) -3'-carbazolyl) -4,6-bis (trichloromethyl) -s-
Triazine, 2- (N-cyclohexyloxycarbonylmethyl-3′-carbazolyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (9-n-butyl-3-carbazolyl) -4,6- Bis-trichloromethyl-s-triazine, 2- (9-ethoxycarbonylmethyl-3-carbazolyl) -4,6-bis-trichloromethyl-s-triazine, 2- (9-n-octyl-3)
-Carbazolyl) -4,6-bis-trichloromethyl-
s-triazine, 2- [9- (2-phenoxyethyl)
-3-carbazolyl] -4,6-bis-trichloromethyl-s-triazine, 2- (4-methylthiophenyl)
-Bis (4,6-trichloromethyl) -s-triazine, 2- (4-methoxy-β-styryl) -bis (4,
6-trichloromethyl) -s-triazine, 2- (3-
Chlorophenyl) -bis (4,6-trichloromethyl)
-S-triazine and the like.

Examples of onium salt compounds include diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphonate, diphenyliodonium hexafluoroarsenate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium trifluoroacetate, diphenyliodonium-p-toluenesulfonate, 4-methoxyphenylphenyliodonium tetrafluoroborate,
4-methoxyphenylphenyliodonium hexafluorophosphonate, 4-methoxyphenylphenyliodonium hexafluoroarsenate, 4-methoxyphenylphenyliodonium trifluoromethanesulfonate, 4-methoxyphenylphenyliodonium trifluoroacetate, 4-methoxyphenyliodonium-p-toluene Sulfonate, bis (4-ter
t-Butylphenyl) iodonium tetrafluoroborate and other diaryliodonium salts, triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluorophosphonate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium trifluoroacetate, 4-methoxyphenyldiphenylsulfonium trifluoro Romethanesulfonate, 4-methoxyphenyldiphenylsulfonium trifluoroacetate, 4-phenylthiophenyldiphenyltrifluoromethanesulfonate, 4-
Examples thereof include triarylsulfonium salts such as phenylthiophenyldiphenyltrifluoroacetate, 4-methoxyphenyldiphenylsulfonium hexafluorophosphonate, and 4-phenylthiophenyldiphenylhexafluorophosphonate.

The photo-acid generator as described above can be used together with a sensitizer. Such sensitizers include thioxanthones, xanthones, and the like.

If the photo-acid generator as described above is less than 3 wt% with respect to the resin solid content, a sufficient amount of acid is not generated by exposure and the cross-linking between the resin and the cross-linking agent does not proceed sufficiently. The residual film rate after development decreases, and the heat resistance and chemical resistance of the pixel decrease. On the other hand, if it exceeds 20 wt%, the pattern swells, so that it is preferably used in an amount of 3 to 20 wt%, preferably 5 to 15 wt%.

As the solvent, methanol, ethanol,
Toluene, xylene, ethyl cellosolve, ethyl cellosolve acetate, methyl cellosolve, methyl cellosolve acetate, diglyme, cyclohexanone, ethylbenzene, isoamyl acetate, n-amyl acetate, propylene glycol monomethyl ether (acetate), propylene glycol monoethyl ether (acetate), diethylene glycol , Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether,
Triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, liquid polyethylene glycol, 1-methoxy-
2-Propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, ethyl lactate, ethyl ethoxy propionate, etc. are used, but they are dissolved by the monomer composition of the resin, the cross-linking agent, the photo-acid generator, etc. Since the properties are different, a single solvent or a plurality of solvents are appropriately selected.

Further, in the photosensitive composition of the present invention, various additives such as fillers such as silica, talc and clay, thixotropic agents such as Aerosil, silicone,
A fluorine-based leveling agent, an antifoaming agent, a pigment, a coloring agent such as a dye, a dispersant, and the like can be added for the purpose of enhancing the performance of the photosensitive composition.

When the photosensitive composition according to the present invention as described above is used, the lower part of the pattern is sufficiently cured due to the difference in reaction mechanism even if the light does not sufficiently penetrate to the lower part of the pattern. Therefore, it is possible to obtain a forward taper shape which has a wide range of high sensitivity, high adhesiveness, and developability and which is unlikely to be an overhang shape (inverse taper shape).

[0020]

【Example】

<Example 1> As a resin according to the present invention, 18.8 parts by weight of hydroxyethyl methacrylate (a monomer having an alcoholic hydroxyl group), 12.5 parts by weight of methyl methacrylate, and 68.8 parts by weight of butyl methacrylate were mixed with ethyl cellosolve. (Solvent) Dissolve in 300 parts by weight and add 0.75 parts by weight of azoisobutyronitrile under a nitrogen atmosphere to give 7
It was obtained by reacting at 0 ° C. for 5 hours and copolymerizing. The weight average molecular weight of this resin is 250 in terms of gel permeation chromatograph (hereinafter referred to as GPC) polystyrene.
It was 00.

This was diluted with ethyl cellosolve to a resin concentration of 20%, and 27.143 g of this diluted resin was added.
Alkylated melamine resin (manufactured by Sanwa Chemical Co., Ltd .: “M
W-30M ") 0.271 g, as a photo-acid generator 2-
(4'-Methoxy-1'-naphthyl) -4,6-bis (trichloromethyl) -s-triazine (0.3 g) and cyclohexanone (12.286 g) as a sensitizer were added and well stirred to obtain a photosensitive composition.

Example 2 As the resin according to the present invention, 23.5 parts by weight of methacrylic acid (a monomer having a carboxylic acid group), 11.8 parts by weight of methyl methacrylate, and 64.7 parts by weight of butyl methacrylate, It was dissolved in 300 parts by weight of ethyl cellosolve (solvent), 0.75 parts by weight of azoisobutyronitrile was added in a nitrogen atmosphere, and the mixture was reacted at 70 ° C. for 5 hours to obtain a copolymer. The GPC of this resin was 25,000 in terms of polystyrene. Hereinafter, a photosensitive composition was prepared in the same manner as in Example 1.

<Example 3> As the resin according to the present invention, 20 parts by weight of methacrylic acid (a monomer having a carboxylic acid group), 15 parts by weight of hydroxyethyl methacrylate (a monomer having an alcoholic hydroxyl group), and methyl methacrylate. 10 parts by weight and 55 parts by weight of butyl methacrylate were dissolved in 300 parts by weight of ethyl cellosolve (solvent), 0.75 parts by weight of azoisobutyronitrile was added in a nitrogen atmosphere, and the mixture was reacted at 70 ° C. for 5 hours for copolymerization. I got it. The weight average molecular weight of this resin is 25 in terms of GPC and polystyrene.
It was 000. Hereinafter, a photosensitive composition was prepared in the same manner as in Example 1.

Comparative Example 1, Difference in Resin As a resin, 40 parts by weight of methyl methacrylate and 60 parts by weight of butyl methacrylate were dissolved in 300 parts by weight of ethyl cellosolve,
Azoisobutyronitrile (solvent) 0.7 under nitrogen atmosphere
It was obtained by adding 5 parts by weight and reacting at 70 ° C. for 5 hours for copolymerization. The weight average molecular weight of this resin was 25,000 in terms of GPC and polystyrene. Hereinafter, a photosensitive composition was prepared in the same manner as in Example 1.

<Comparative Example 2, difference in cross-linking agent> The resin of Example 3 was used as a resin and this was diluted with ethyl cellosolve to a resin concentration of 20%. 8 g of trimethylolpropane triacrylate as an alternative monomer and 2 as a photo-acid generator
6 g of-(4'-methoxy-1'-naphthyl) -4,6-bis (trichloromethyl) -s-triazine was added and well stirred to obtain a photosensitive composition.

The photosensitive compositions of the above examples were spin-coated (2000 rpm, 5 seconds) on a substrate and dried. Pixel size 30μm after prebaking at 90 ℃ for 1 minute
Exposure was performed using a mask of × 100 μm. 50 exposure
It was mJ / cm ² . Post E for 1 minute at 115 ° C
After x-posure Bake (hereinafter referred to as PEB), it was developed with a 1% sodium hydroxide solution and thoroughly washed with water.
Further, it was baked at 130 ° C. for 1 hour to be fixed.

The photosensitive composition of the above Comparative Example was spin-coated (1000 rpm, 5 seconds) on a substrate and dried. Pixel size 30μ after pre-bake at 70 ℃ for 20 minutes
Exposure was performed using an m × 100 μm mask. The exposure amount is 8
It was 0 mJ / cm ² . After that, it was developed with a 1% sodium carbonate solution and thoroughly washed with water. Further, it was baked at 130 ° C. for 1 hour to be fixed.

For these, the sensitivity is measured by the following method. When the substrate is coated with a film thickness of 1.4 μm and prebaked is taken as 100%, the exposure amount is 1, 3, 5, 10,
Shaking at 30, 50 ... (mJ / cm ² ) to quantify how hard the film thickness obtained upon development is to the initial film thickness. The sensitivity is defined as the point where it reaches 97% or more of the initial level. In addition, the tapered shape is 80 ° with a scanning electron microscope.
Observation was performed at 10,000 times the inclination. In addition, a tape peeling test was performed by performing cross-cut on the product that had been subjected to the development processing. The one that adhered was marked with ◯, and the one that peeled off was marked with x. The results are shown below.

[0029]

[Table 1]

[0030]

As described above, the photosensitive resin composition of the present invention uses a copolymer having an alcoholic hydroxyl group and / or a carboxylic acid group as a main component of the resin, which is used as a crosslinking agent By blending with an acid generator and solvent,
It has high sensitivity and a wide range of developability, there is no problem in adhesion after development, and even if it is overdeveloped, it is unlikely to have an overhang shape (inverse taper shape). It became suitable for manufacturing various etched parts.

Claims (3)

[Claims] 1. A photosensitive composition comprising a resin, a photoacid generator, a crosslinking agent and a solvent, wherein the main component of the resin is a copolymer having an alcoholic hydroxyl group and / or a carboxylic acid group. And a photosensitive composition. 2. The weight ratio of the monomer having an alcoholic hydroxyl group and / or a carboxylic acid group in the copolymer is 5
The photosensitive composition according to claim 1, wherein the photosensitive composition is about 50 wt%. 3. The copolymer has a molecular weight of 3000 to 15
It is 0000, The photosensitive composition of Claim 1 or 2 characterized by the above-mentioned.