JPH0635183A - Positive type resist composition and production of color filter using the same - Google Patents

Abstract

PURPOSE:To provide the positive type resist compsn. which is excellent in various performances, such as resolution and heat resistance, and the process for production of the color filters with easy process administration, etc. CONSTITUTION:This positive type resist compsn. is formed by incorporating a resin which can be cured by an acid, quinone diazide compd., crosslinking agent, photo oxidation agent, dyestuff 3 and solvent therein. This process consists in applying this positive type resist compsn. on a base body 5, then exposing the compsn. through a mask, developing away the exposed parts to form positive type colored images 7, subjecting the colored images 7 which are left as unexposed parts to full-surface exposing and curing the images.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive 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 forming a pattern with a photoresist and then dyeing it, or a dye or It is manufactured using 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 such as complexity of the dyeing process and difficulty of process control. 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 proposes a method of 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). 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-
There is a problem in the stability of the color pattern in the method described in Japanese Patent No. 128703, in which the color material in which the photosensitizer and the dye are dissolved in the resin solution is patterned and spin-on-glass (SOG) is used as the protective film. . Further, in a method using a positive resist composition containing a novolac resin, a quinonediazide compound and a dye as described in JP-A-2-127602 and JP-A-4-175753, heating at high temperature for a long time after pattern formation is carried out. Therefore, there is a problem in heat resistance of the novolac resin.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and provides a positive resist composition excellent in various performances such as resolution and heat resistance, and a process for controlling the process such as using the positive resist composition. An easy color filter manufacturing method is provided.

[0004]

The present invention relates to a positive resist composition containing an acid-curable resin, a quinonediazide compound, a crosslinking agent, a photoacid generator, a dye and a solvent, and a positive resist composition on a substrate. A method for producing a color filter, which comprises exposing to light through a mask after application, to develop and remove the exposed part to form a positive colored image, and then exposing and curing the entire colored image which is the unexposed part. Is.

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 alkyl group represented by R and R _{1 to} R ₇ includes a methyl, ethyl, n-propyl or n-butyl group, and the preferred 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. Further, the compounds represented by the formulas (iii) to (vi) are disclosed in JP-A-1-
It is a known compound described in Japanese Patent No. 293339. Formula- (C
Preferred compounds having a group represented by H ₂ ) _s OR include, for example, hexamethoxymethylolated melamine,
Hexamethoxyethylol melamine, hexamethoxypropyrolated melamine and the like can be mentioned.

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:

Examples of the quinonediazide compound include o
-Naphthoquinone diazide-5-sulfonic acid ester or sulfonic acid amide, or o-naphthoquinone diazide-
4-sulfonic acid ester, sulfonic acid amide, etc. are mentioned. These esters or amides are represented by the general formula (I) in JP-A-2-84650 and JP-A-3-49437.
It can be produced by a known method using the phenol compound described in 1.

As the dye, a dye having a spectrum desirable for a color filter and capable of being dissolved in a solvent which 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 amount of the quinonediazide compound, the cross-linking agent, the photo-acid generator and the dye is usually
2 to 20 and 2 for resin solution that can be cured by acid
-20, 2-20 and 0.1-20% by weight.

The positive resist is one in which the exposed portion is removed and the unexposed portion remains as a positive colored image by utilizing the difference in solubility in an alkali developing solution due to exposure. That is, the quinonediazide compound is decomposed by exposure and becomes soluble in the alkali developing solution, while the unexposed portion acts to suppress the dissolution of the resin in the alkali developing solution. Then, the photo-acid generator has a function of generating an acid to cure the positive type colored image when the unexposed portion is entirely exposed. For the exposure, for example, ultraviolet rays such as a mercury lamp, deep ultraviolet rays, electron beams or X-rays are used.

1 to 5 show one embodiment of the method of the present invention.
After applying a composition containing an acid-curable resin, a quinonediazide compound, a photoacid generator, a crosslinking agent, a dye and a solvent to a substrate, the solvent is evaporated (see FIG. 1). The photosensitive agent in the exposed area is decomposed by exposure through a mask (see FIG. 2).
After development, a positive colored image of the unexposed area is obtained (see FIG. 3). The positive type colored image of the unexposed portion is entirely exposed to cure (hold) (see FIG. 4). The method of the present invention in which the entire surface is exposed to cure the resin enhances the solvent resistance of the positive type colored image.

[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. For the manufacturing method of the color filter, a quinonediazide compound, a dye, a resin that can be cured with an acid are used on a silicon wafer,
After spin coating a positive resist composition containing a cross-linking agent, a photo-acid generator and a solvent and evaporating the solvent by heating,
Exposure was performed through a mask to decompose the quinonediazide compound. Next, after development, the entire surface was exposed (and heated if necessary) to obtain a mosaic pattern. Exposure is Hitachi's i-line exposure stepper HITACHI LD-5010-i (NA = 0.
40). The developer is Sumitomo Chemical Co., Ltd.
SOPD or SOPD-B was used.

Example 1 3.4 parts of cresol novolak resin (polystyrene-equivalent weight average molecular weight 4300) obtained from a mixture of m-cresol / p-cresol / formaldehyde (reaction molar ratio = 5/5 / 7.5).

[0022]

[Chemical 5]

O-naphthoquinonediazide-5-sulfonate prepared by using a phenolic compound represented by the formula (on average, two hydroxyl groups are esterified) 1.8
Part, hexamethoxymethylolated melamine 0.5 part, ethyl lactate 20 parts and Sumitomo Chemical Co., Ltd. oleozole blue EL 1 part, and the following formula

[0024]

[Chemical 6]

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

Example 2 A silicon wafer was spin-coated with the positive resist composition obtained in Example 1, and then the solvent was evaporated. After exposing this silicon wafer, the exposed portion was removed by alkali development to obtain a positive type colored pattern having a resolution of 0.8 μm. After exposing the whole surface, it was heated at 150 ° C. for 15 minutes to obtain a cyan color filter.

Example 3 A photoacid generator was prepared according to the following formula.

[0028]

[Chemical 7]

A positive type colored image having a resolution of 1 μm was obtained in the same manner as in Example 1 except that the compound represented by the formula (1) was used. This was exposed on the entire surface and then heated at 110 ° C. for 3 minutes to obtain a cyan color filter.

Example 4 10 parts of cresol novolac resin used in Example 1, 2 parts of hexamethoxymethylolated melamine, o-naphthoquinonediazide-5 of the phenol compound used in Example 1
A positive resist composition was obtained by mixing 1.8 parts of sulfonic acid ester, 60 parts of ethyl cellosolve acetate, 1 part of the photo-acid generator used in Example 1, and 1 part of Oraba Pink (magenta dye) manufactured by Ciba-Geigy. . A silicon wafer was spin-coated with this positive resist composition, and then the solvent was evaporated. This silicon wafer was exposed and then alkali-developed to obtain a positive colored image having a resolution of 1 μm. The whole surface was exposed and then heated at 110 ° C. for 5 minutes to obtain a magenta color filter.

Example 5 10 parts of a copolymer of polymethylmethacrylate and maleic anhydride, 2 parts of hexamethoxymethylolated melamine, 10 parts of o-naphthoquinonediazide-5-sulfonic acid ester used in Example 1, dimethylformamide A positive resist composition was obtained by mixing 80 parts, 1 part of the photo-acid generator used in Example 3 and 2 parts of Sumitomo Chemical Co., Ltd. Oreosol Blue EL. A silicon wafer was spin-coated with this positive resist composition, and then the solvent was evaporated. This silicon wafer was exposed and then alkali-developed to obtain a positive colored image having a resolution of 1 μm. This was exposed on the entire surface and then heated at 120 ° C. for 5 minutes to obtain a cyan color filter.

Example 6 10 parts of cresol novolac resin used in Example 1, 2.5 parts of hexamethylolated melamine, o-used in Example 1
5 parts of naphthoquinonediazide-5-sulfonate,
A positive resist composition was obtained by mixing 60 parts of ethyl cellosolve acetate, 1 part of the photo-acid generator used in Example 3, and 2 parts of Oleosol Yellow 2G manufactured by Sumitomo Chemical Co., Ltd. A silicon wafer was spin-coated with this positive resist composition, and then the solvent was evaporated. This silicon wafer was exposed and then alkali-developed to obtain a positive colored image having a resolution of 1 μm. After exposing the entire surface, 120 ℃
* Heated for 10 minutes to obtain a yellow color filter. Separately, a positive resist composition was obtained in the same manner as above except that the magenta dye used in Example 4 was used in place of the above-mentioned Oreosol Yellow 2G. This resist composition was coated on the above yellow color filter and operated in the same manner as in the case of obtaining the yellow color filter,
A magenta color filter was obtained. Further, the positive type resist composition obtained in the same manner as described above was coated on a magenta color filter except that 2 parts of oleozole blue EL used in Example 1 was used instead of oleozole yellow 2G. A cyan color filter was obtained by treating in the same manner as in 2. In this way, yellow, magenta and cyan complementary color system color filters were obtained.

[0033]

The positive 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 positive resist 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 produced. can do.

[Brief description of drawings]

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

FIG. 2 shows a state in which a quinonediazide compound and a photoacid generator in an exposed area have disappeared.

FIG. 3 is a positive colored image after development.

FIG. 4 is a positive colored image that is cured (retained) after being exposed on the entire surface.

[Explanation of symbols]

 1 Resist Composition 2 Quinonediazide Compound 3 Dye 4 Photo Acid Generator 5 Substrate 6 Mask 7 Positive Colored Image

Claims (4)

[Claims] 1. A positive resist composition comprising an acid-curable resin, a quinonediazide compound, a crosslinking agent, a photoacid generator, a dye and a solvent. 2. The positive resist composition according to claim 1, wherein the acid-curable resin is a novolac resin and the quinonediazide compound is an o-naphthoquinonediazide compound. 3. A cross-linking agent is represented by the following formula: — (CH ₂ ) _s OR (wherein R represents a hydrogen atom or a lower alkyl group,
Represents an integer of 1 to 4. The positive resist composition according to claim 1, which is a compound having a group represented by the formula (1). 4. A positive resist composition according to claim 1 is coated on a substrate, exposed through a mask, and the exposed portion is developed and removed to form a positive colored image. Then, the unexposed portion is exposed. A method for producing a color filter, which comprises exposing the above colored image to the entire surface and curing the same.