JPH0651514A - Negative type resist composition and production of color filter using the same - Google Patents

Abstract

PURPOSE:To provide a negative type resist compsn. excellent in various properties such as resolution and heat resistance and a method for producing a color filter with the resist compsn. under easy process control. CONSTITUTION:This negative type resist compsn. 1 contains a resin curable with an acid, a crosslinking agent, an optical acid generating agent 2, a dye and a solvent. A substrate is coated with this compsn. 1 and exposure is carried out through a mask 3. The exposed part is cured and the unexposed part is removed by development to produce the objective color filter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative resist composition used for color filters and a method for producing color filters using the same.

[0002]

2. Description of the Related Art A color filter, particularly a color filter for a solid-state image pickup device such as a charge-coupled device (CCD) or a liquid crystal display device (LCD), is formed by first patterning a photosensitive gelatin film or a photosensitive casein film and then dyeing solution. It is manufactured by using a method of dyeing inside or a method of forming a pattern with a photoresist to which a coloring material such as a pigment is added. However, the former method has problems that it is difficult to control the photosensitive material such as gelatin or casein and the dyeing solution (color density, pH, etc.), and the patterning process (accuracy) is controlled. On the other hand, as the latter method, for example, a method using a resist in which a pigment is dispersed as described in JP-A-4-163552 is proposed. This method is not suitable for producing a CCD color filter that requires high resolution because the pigment itself contains particles of about 1 μm. JP-A-1-152449
In the publication, a method using a resist in which a pigment is dispersed in a copolymer of acrylic acid or methacrylic acid and alkyl or benzyl acrylate (or methacrylate) is proposed. However, this method is complicated because it requires a step of dispersing the pigment particles by a ball mill or the like so that the particle size becomes 0.7 μm or less. In addition, JP-A-4
In the method of patterning a coloring material in which a photosensitizer and a dye are dissolved in a resin solution and using spin-on-glass (SOG) as a protective film as described in JP-A-128703, there is a problem in the stability of the color pattern. is there. Furthermore, JP-A-2-127602
In the method of using a positive resist composition containing a novolac resin, a quinonediazide compound and a dye as described in JP-A-4-175753, heating at high temperature for a long time after pattern formation requires novolak resin. There is a problem with heat resistance.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the above-mentioned conventional techniques, and provides a negative resist composition excellent in various performances such as resolution and heat resistance, and process control using the same. An easy color filter manufacturing method is provided.

[0004]

The present invention relates to a negative resist composition containing an acid-curable resin, a cross-linking agent, a photo-acid generator, a dye and a solvent, and after coating the same on a substrate. A method for producing a color filter, which comprises curing the exposed portion by exposure through a mask and then developing and removing the non-exposed portion.

Examples of the resin which can be cured with an acid include a resin having a phenolic hydroxyl group or a carboxyl group, or J. Photopolym. Sci. Technol. Vol.3, No. 3
(1990), pages 235 to 247, copolymers containing a hydroxystyrene structure, that is, a copolymer of p-hydroxystyrene and p-acetoxymethylstyrene. Examples of the resin having a carboxyl group include a copolymer of polymethacrylate and maleic anhydride. Examples of the resin having a phenolic hydroxyl group include an alkali-soluble phenol resin or novolac resin. Examples of the novolac resin include those obtained by condensing phenols and aldehydes in the presence of an acid catalyst. Examples of the phenols include phenol, cresol, ethylphenol, butylphenol, xylenol, phenylphenol, catechol, resorcinol, pyrogallol, naphthol, bisphenol C or bisphenol A. These phenols may be used alone or in combination of two or more.
Examples of the aldehydes include aliphatic or aromatic aldehydes such as formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde or benzaldehyde. A resin that can be cured with an acid, such as a resin having a phenolic hydroxyl group, may be adjusted in molecular weight distribution by means such as fractionation, if necessary. Further, phenols such as bisphenol A or bisphenol C may be added to the resin which can be cured with an acid.

Examples of the cross-linking agent include the following formula-(CH ₂ ) _s OR (wherein R represents a hydrogen atom or a lower alkyl group, s
Represents an integer of 1 to 4. And a melamine having a group represented by the formula (1). As the compound having a group represented by the above formula, for example, the following formula

[0007]

[Chemical 1]

[In the formula, Z represents —NR ₁ R ₂ or a phenyl group. R _{1 to} R ₆ are each a hydrogen atom, — (CH ₂ ) _s OH, provided that at least one of them represents — (CH ₂ ) _s OH or — (CH ₂ ) _s OR _7.
Or - it represents a (CH _{2) s} OR _7. R ₇ represents a lower alkyl group. s represents an integer of 1 to 4. ] The compound shown by the following, or the following formula

[0009]

[Chemical 2]

[0010]

[Chemical 3]

Examples thereof include compounds represented by The lower alkyl group represented by R and R ₇ includes a methyl, ethyl, n-propyl or n-butyl group, and the preferred lower alkyl group includes a methyl or ethyl group. Each of the compounds represented by formulas (i) to (ii) can be produced by condensing p-cresol or t-butylphenol with formaldehyde under basic conditions. The compounds represented by formulas (iii) to (vi) are disclosed in
It is a known compound described in JP-A-293339. Expression −
Preferred compounds having a group represented by (CH ₂ ) _s OR include, for example, hexamethoxymethylolated melamine, hexamethoxyethylolated melamine, hexamethoxypropyrolated melamine and the like.

The photoacid generator is not particularly limited as long as it can generate an acid directly or indirectly by light. For example, a trihalomethyltriazine-based compound described in JP-A-4-163552, disulfone compounds described in 1-57777 JP, the _{formula, R 8 -SO 2 -SO 2 -R} 9 -SO 2 -SO 2 -R 10 ( wherein, R ₈ and R ₁₀ are each independently A compound represented by optionally substituted aryl, aralkyl, alkyl, cycloalkyl or heterocyclic group, and R ₉ represents optionally substituted aryl), JP-A-1-2933.
No. 39, a photoacid generator containing a sulfonic acid ester group, represented by the following formula CF ₃ —SO ₂ O— (CH ₂ ) _n —Y (wherein Y represents an aryl group which may be substituted). n is 0
Or represents 1. ), A compound represented by the formula: CF ₃ —SO ₂ O— [C (Y ₁ ) (Y ₂ )] _m —C
(O) -Y ₃ (wherein, Y ₁ and Y ₂ are each independently optionally substituted by alkyl, alkoxy or aryl group, Y ₃
Is an optionally substituted aryl group, and m is 1 or 2
Are respectively represented. ), A compound represented by the formula: CF ₃ —SO ₂ O—N (Y ₄ ) —C (O) —Y ₅ (wherein Y ₄ represents an optionally substituted alkyl group, and
₅ represents an aryl group which may be substituted, respectively. ), A compound represented by the formula: CF ₃ —SO ₂ O—N═C (Y ₆ ) (Y ₇ ) (wherein Y ₆ represents a hydrogen atom or an optionally substituted alkyl or aryl group, Y ₇ Each represents an optionally substituted aryl group), a compound represented by the following formula:

[0013]

[Chemical 4]

Examples include onium salts represented by:

As the dye, a dye having a spectrum desirable for a color filter and capable of being dissolved in a solvent that dissolves the above-mentioned acid-curable resin as it is or in a modified form can be used. Examples of these dyes include oil-soluble dyes, disperse dyes, reactive dyes, acid dyes and direct dyes. Specific examples of these dyes include Sumiplast or oleozole dyes manufactured by Sumitomo Chemical Co., Ltd., Orazole dyes manufactured by Ciba-Geigy, Neozapon dyes manufactured by BASF.

Examples of the solvent include methyl cellosolve,
Ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol dimethyl ether, ethylene glycol monoisopropyl ether, propylene glycol monomethyl ether, N,
N-dimethylacetamide, N-methylpyrrolidone, γ
-Butyrolactone, cyclohexanone, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl lactate, ethyl lactate, ethyl pyruvate, dimethylformamide and the like can be mentioned. These solvents may be used alone or in combination of two or more.

The acid-curable resin is usually dissolved in a solvent in a proportion of about 2 to 50% by weight. The amounts of the cross-linking agent, the photo-acid generator and the dye are usually 2 to 20, 2 to 20 and 0.1 to 20% by weight based on the acid-curable resin solution.
Add in a ratio of about.

The negative resist utilizes the fact that the acid generated from the photo-acid generator upon exposure cures the resin which can be cured by the acid. That is, the unexposed area containing the uncured resin is removed by the alkali developing solution, while the exposed area containing the cured resin is insoluble in the alkaline developing solution and remains as a negative pattern. For exposure,
For example, ultraviolet rays from a mercury lamp or the like, far ultraviolet rays, electron beams or X-rays are used.

1 to 3 show one embodiment of the method of the present invention.
The substrate is coated with a negative resist composition containing an acid-curable resin, a photoacid generator, a crosslinking agent, a dye and a solvent, and then the solvent is evaporated (see FIG. 1). By exposing through a mask, the photo-acid generator in the exposed area is decomposed to cure an acid-curable resin (see FIG. 2). The negative resist composition in the unexposed area is removed by development (see FIG. 3). The method of the present invention in which the resin is cured by exposure increases the solvent resistance of the negative pattern.

[0020]

EXAMPLES Next, the present invention will be described more specifically by way of examples. In the examples, "part" means "part by weight". The common conditions in the following examples are as follows. Regarding the method for producing the color filter, a silicon wafer is spin-coated with a negative resist composition containing a dye, a resin curable with an acid, a cross-linking agent, a photo-acid generator and a solvent, and the solvent is evaporated by heating, Exposure was performed through a mask to decompose the photo-acid generator. Then, if necessary, after heating, it was developed to obtain a negative pattern. Hitachi uses the i-line exposure stepper HITACHI LD-5010-i (NA =
0.40) was used. The developer is SO manufactured by Sumitomo Chemical Co., Ltd.
PD or SOPD-B was used.

Example 1 Maruka lyncur-c manufactured by Maruzen Oil Co., Ltd.
hm10 parts, hexamethoxymethylol melamine 2 parts, ethyl lactate 100 parts, Sumitomo Chemical Co., Ltd. oleozole blue EL 2 parts and the following formula

[0022]

[Chemical 5]

A negative resist composition was obtained by mixing 1 part of a photoacid generator represented by

Example 2 The negative resist composition obtained in Example 1 was spin-coated on a silicon wafer, and then the solvent was evaporated. After exposing this silicon wafer, it was heated at 120 ° C. Then, the unexposed portion was removed by alkali development to obtain a cyan color filter having a resolution of 1 μm.

Example 3 10 parts of cresol novolac resin (polystyrene-converted weight average molecular weight 4300) obtained from a mixture of m-cresol / p-cresol / formaldehyde (reaction molar ratio = 5/5 / 7.5), hexamethoxymethylol melamine Two
Parts, 60 parts of ethyl cellosolve acetate, 1 part of the photoacid generator used in Example 1 and 2 parts of Orazo Pink manufactured by Ciba-Geigy Co., Ltd. to obtain a negative resist composition. A silicon wafer was spin-coated with this negative resist composition, and then the solvent was evaporated. After exposing this silicon wafer, it was heated at 100 ° C. Then, the non-exposed area was removed by alkali development to obtain a magenta color filter having a resolution of 1 μm.

Example 4 10 parts of polyvinylphenol, 2 parts of hexamethoxymethylolated melamine, 60 parts of ethyl cellosolve acetate, 2 parts of Oleosol Yellow 2G manufactured by Sumitomo Chemical Co., Ltd. and 1 part of the photo-acid generator used in Example 1 Were mixed to obtain a negative resist composition. A silicon wafer was spin-coated with this negative resist composition, and then the solvent was evaporated. After exposing this silicon wafer, it was heated at 120 ° C. Then, the unexposed area was removed by alkali development to obtain a yellow color filter having a resolution of 1 μm.

Example 5 10 parts of a copolymer of vinylphenol and methyl methacrylate (reaction molar ratio = 1: 1), 2 parts of hexamethoxymethylolated melamine, 80 parts of dimethylformamide, the following formula

[0028]

[Chemical 6]

A negative resist composition was obtained by mixing 1 part of the photo-acid generator represented by and 2 parts of Oleosol Blue EL manufactured by Sumitomo Chemical Co., Ltd. A silicon wafer was spin-coated with this negative resist composition, and then the solvent was evaporated. After exposing this silicon wafer, it was heated at 120 ° C. Then, the non-exposed area is removed by alkali development to 1
A color filter having a resolution of μm was obtained.

Example 6 10 parts of cresol novolac resin used in Example 3, 2.5 parts of hexamethoxymethylolated melamine, 60 parts of ethyl cellosolve acetate, photoacid generator 1 used in Example 4
And Sumitomo Chemical Co., Ltd. Oreosol Yellow 2G
Two parts were mixed to obtain a negative resist composition. A silicon wafer was spin-coated with this negative resist composition, and then the solvent was evaporated. After exposing this silicon wafer, it was heated at 120 ° C. Then, develop with alkali to 1μ
A yellow color filter having a resolution of m was obtained.
Separately, a negative resist composition was obtained in the same manner as described above, except that Orasol Pink manufactured by Ciba-Geigy Co., Ltd. used in Example 3 was used in place of Oreosol Yellow 2G. This resist composition was applied onto the above yellow color filter and operated in the same manner as in the case of obtaining the yellow color filter to obtain a magenta color filter. Furthermore, Example 1 was used instead of Oreosol Yellow 2G.
Except using 2 parts of Oreozole Blue EL used in
The negative resist composition obtained in the same manner as above was coated on a magenta color filter and treated in the same manner as in Example 2 to obtain a cyan color filter. In this way
A color filter of complementary colors of yellow, magenta and cyan was obtained.

[0031]

The negative resist composition of the present invention is excellent in various properties such as resolution and heat resistance. Further, according to the method of the present invention, since a negative resist composition containing a resin curable by an acid, a cross-linking agent and a photo-acid generator is used, a color filter excellent in various properties such as solvent resistance and fineness can be easily formed. Can be manufactured.

[Brief description of drawings]

FIG. 1 is a negative resist composition applied to a substrate.

FIG. 2 shows a state in which a photoacid generator in an exposed area has disappeared.

FIG. 3 is a negative pattern after development.

[Explanation of symbols]

 1 Negative Resist Composition 2 Photo Acid Generator 3 Mask 4 Negative Pattern 5 Substrate

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G03F 7/029 H01L 21/027

Claims (3)

[Claims] 1. A negative resist composition comprising an acid-curable resin, a crosslinking agent, a photoacid generator, a dye and a solvent. 2. The acid-curable resin is a novolac resin, and the cross-linking agent is represented by the following formula:-(CH ₂ ) _S OR (wherein R represents a hydrogen atom or a lower alkyl group, s
Represents an integer of 1 to 4. The negative resist composition according to claim 1, which is a compound having a group represented by the formula (1). 3. A color filter comprising coating the negative resist composition according to claim 1 on a substrate, curing the exposed portion by exposure through a mask, and then developing and removing the unexposed portion. Production method.