TWI417651B - Resist composition - Google Patents

Description

Photoresist composition

The present invention relates to a photoresist composition which is a photoresist composition capable of inducing radiation such as ultraviolet rays, far ultraviolet rays, X-rays, and electron beams, and has excellent safety and excellent coating properties when used. The residual film ratio at the time of development, the uniformity of the pattern line width after development, and the excellent adhesion at the time of development.

Microfabrication is required in the production of integrated circuits, color filters, liquid crystal elements, etc. In order to meet this requirement, photoresists have been conventionally used. Usually, the photoresist has a positive type and a negative type, and is usually a photoresist composition in a solution state of a solvent.

The photoresist composition is applied onto a substrate such as a ruthenium substrate or a glass substrate by a well-known method such as spin coating, roll coating, slit coating, or inkjet coating, and then pre-baked to form a photoresist film, and then, according to the photoresist The photosensitive wavelength range is exposed and developed by particle rays such as ultraviolet rays, far ultraviolet rays, X-rays, and electron beams, and then dry etching is performed as necessary to form a desired photoresist pattern.

The solvent used for the above-mentioned photoresist composition is conventionally used in various solvents, and can be selected and used in consideration of solubility, coatability, sensitivity, developability, and characteristics of the formed pattern. For example, ethylene glycol monoethyl ether acetate is known as a solvent having excellent properties such as solubility, coatability, and photoresist formation characteristics, but in recent years, it has been pointed out that it is safe for human body, and therefore requires A solvent which has high safety, resin solubility, and excellent solubility of an initiator, and can improve properties such as photoresist formation characteristics.

As a solution to these problems, for example, Patent Document 1 uses propylene glycol monomethyl ether acetate or the like instead of ethylene glycol monoethyl ether acetate as a solvent. However, such a solvent which is considered to have higher safety than ethylene glycol monoethyl ether acetate has a problem that characteristics such as photoresist formation characteristics and solubility are insufficient. For example, when propylene glycol monomethyl ether acetate is used, when a photoresist is applied onto a substrate, the amount of residual solvent in the film is small, and abnormal film thickness distribution, uniformity of line width, and adhesion of the photoresist film during development are lowered. The problem.

Further, there is a technique for improving the solubility of a resin and the solubility of an initiator by using β-propylene glycol monomethyl ether acetate, for example, in Patent Document 2, but in terms of resin solubility and initiator solubility, insufficient.

[Patent Document 1] Special Fair 3-1659

[Patent Document 2] Japanese Patent Publication No. 6-324483

An object of the present invention is to provide a photoresist composition which can improve not only the solubility at the time of resistive modulation but also the adhesion of a photoresist film during development, and can also improve the stability of photoresist and have excellent safety.

As a result of intensive research, the inventors of the present invention have found that the above object can be attained by using a specific organic solvent.

That is, the present invention provides a photoresist composition comprising a photoresist composition comprising a photoresist component and an organic solvent, wherein the solvent comprises a solvent selected from the group consisting of (a1) C _3-6 alkanediol, (a2) monoalkane. Oxy-C _3-6 alkanediol, (b1) C _5-6 alkanediol monoacetate, (b2) monoalkoxy-C _3-6 alkanediol monoacetate, ( C1) A solvent of at least one of the group consisting of C _5-6 alkanediol diacetate and (c2) monoalkoxy-C _3-6 alkanediol diacetate.

Two or more organic solvents may be combined in the photoresist composition. A preferred combination of organic solvents is exemplified by (1) selected from the group consisting of (a1) C _3-6 alkanediol, and (a2) monoalkoxy-C _3-6 alkanediol. At least one diol, and selected from (b1') C _3-6 alkanediol monoacetate, (b2) monoalkoxy-C _3-6 alkanediol monoacetate, (c1) a combination of at least one acetate of the group consisting of C _3-6 alkanediol diacetate and (c2) monoalkoxy-C _3-6 alkanediol diacetate; (2) at least one selected from the group consisting of (b1) C _5-6 alkanediol monoacetate and (b2) monoalkoxy-C _3-6 alkanediol monoacetate a monoacetate group and a group selected from the group consisting of (c1') C _3-6 alkanediol diacetate, and (c2) monoalkoxy-C _3-6 alkanediol diacetate a combination of at least one diacetate; (3) selected from the group consisting of (b1') C _3-6 alkanediol monoacetate, and (b2) monoalkoxy-C _3-6 alkanediol At least one monoacetate in the group consisting of monoacetates, and selected from (c1) C _5-6 alkanediol diacetate, and (c2) monoalkoxy-C _3-6 chain A combination of at least one diacetate in the group consisting of alkylene glycol diacetates.

The photoresist composition may further contain at least one solvent selected from the group consisting of alkyl carboxylates and aliphatic ketones as an organic solvent.

According to the present invention, it is possible to provide a photoresist composition which can improve the solubility in modulating a photoresist, and drastically improve the stability of the photoresist while adjusting the drying speed by maintaining the amount of residual solvent in the film during photoresist coating. It can improve the uniformity of film thickness, the uniformity of line width, the adhesion of the photoresist film during development, and the like, and has high safety.

In the present invention, the organic solvent may be selected from (a1) C _3-6 alkanediol, (a2) monoalkoxy-C _3-6 alkanediol, (b1) C _5-6 alkanediol. Monoacetate, (b2) monoalkoxy-C _{3 - 6} alkanediol monoacetate, (c1) C _{5 - 6} alkanediol diacetate, and (c2) monoalkoxy a solvent of at least one of the group consisting of -C _{3 - 6} alkanediol diacetate.

These organic solvents may be used singly or in combination of two or more kinds in any ratio. Further, it may be used in combination with other organic solvents. Further, in the above-mentioned respective organic solvents, the "alkoxy group" is preferably a linear or branched alkyl group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group or a butoxy group.

The C _{3 - 6} alkane diols (A1), can be mentioned, for example, 1, 2, if the carbon number of the alkyl chain is linear or branched chain alkane diol having 3 to 6 of -propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1 , 3-butanediol, 3-ethyl-1,3-butanediol, 1,2-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,3-pentane Alcohol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 1,2-hexanediol, and the like.

The monoalkoxy-C _{3 - 6} alkanediol (a2) is a linear or branched chain having an alkoxy group bonded to the alkyl chain and having an alkyl chain having 3 to 6 carbon atoms. The alkanediol may, for example, be 3-methoxy-1,2-propanediol, 3-ethoxy-1,2-propanediol, 3-propoxy-1,2-propanediol, 3 -butoxy-1,2-propanediol, 2-methoxy-1,3-propanediol, 2-ethoxy-1,3-propanediol, 2-propoxy-1,3-propanediol, 2-butyl Oxy-1,3-propanediol and the like.

The C _{5 - 6} alkanediol monoacetate (b1) may be a linear or branched alkanediol monoacetate having 5 to 6 carbon atoms in the alkyl chain. For example, 3-methyl-1,3-butanediol monoacetate, 3-ethyl-1,3-butanediol monoacetate, 1,2-pentanediol monoacetate , 1,4-pentanediol monoacetate, 1,5-pentanediol monoacetate, 2,3-pentanediol monoacetate, 2,4-pentanediol monoacetate, 2 -methyl-2,4-pentanediol monoacetate, 3-methyl-1,5-pentanediol monoacetate, 1,2-hexanediol monoacetate, and the like.

The monoalkoxy-C _{3 - 6} alkanediol monoacetate (b2) is a linear or branched group having an alkoxy group bonded to an alkyl chain and having a carbon number of 3 to 6 in the alkyl chain. In the case of a chain alkanediol monoacetate, for example, 3-methoxy-1,2-propanediol monoacetate, 3-ethoxy-1,2-propanediol monoethyl bromide may be mentioned. Acid ester, 3-propoxy-1,2-propanediol monoacetate, 3-butoxy-1,2-propanediol monoacetate, 2-methoxy-1,3-propanediol monoacetate 2-Ethoxy-1,3-propanediol monoacetate, 2-propoxy-1,3-propanediol monoacetate, 2-butoxy-1,3-propanediol monoacetate, and the like.

The C _{5 - 6} alkanediol diacetate (c1) may be a linear or branched alkanediol diacetate having 5 to 6 carbon atoms in the alkyl chain. For example, 3-methyl-1,3-butanediol diacetate, 3-ethyl-1,3-butanediol diacetate, 1,2-pentanediol diacetate , 1,4-pentanediol diacetate, 1,5-pentanediol diacetate, 2,3-pentanediol diacetate, 2,4-pentanediol diacetate, 2 -methyl-2,4-pentanediol diacetate, 3-methyl-1,5-pentanediol diacetate, 1,2-hexanediol diacetate, and the like.

The monoalkoxy-C _{3 - 6} alkanediol diacetate (c2) is a linear or branched group having an alkoxy group bonded to an alkyl chain and having a carbon number of 3 to 6 in the alkyl chain. In the case of a chain alkanediol diacetate, for example, 3-methoxy-1,2-propanediol diacetate, 3-ethoxy-1,2-propanediol diethyl ether may be mentioned. Acid ester, 3-propoxy-1,2-propanediol diacetate, 3-butoxy-1,2-propanediol diacetate, 2-methoxy-1,3-propanediol diacetate 2-Ethoxy-1,3-propanediol diacetate, 2-propoxy-1,3-propanediol diacetate, 2-butoxy-1,3-propanediol diacetate, and the like.

Among these organic solvents, particularly preferred organic solvents include 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. a C _{3 - 6} alkanediol such as a diol or 2-methyl-2,4-pentanediol; a monoalkoxy C _{3 - 6} alkanediol such as 3-methoxy-1,2-propanediol ( especially mono C _{1 - 4} alkoxy--C _{3 - 6} alkanediol); 1,5-pentanediol diacetate, 2-methyl-2,4-pentanediol diacetate C _{5 - 6} alkanediol diacetate; monoalkoxy-C _{3 - 6} alkanediol diacetate such as 3-methoxy-1,2-propanediol diacetate (especially single C _{1 - 4} alkoxy--C _{3 - 6} alkane diol diacetate).

A solvent which can obtain an excellent effect alone may, for example, be a C _{5 - 6} chain such as 1,5-pentanediol diacetate or 2-methyl-2,4-pentanediol diacetate. alkylene glycol diacetate; 3-methoxy-1,2-propanediol diacetate monoalkoxy -C _{3 - 6} alkane diol diacetate (especially mono C _{1 - 4} alkoxy Oxy-C _{3 - 6} alkanediol diacetate).

In a preferred combination of two or more kinds, (1) is selected from (a1) C _{3 - 6} alkanediol, and (a2) monoalkoxy-C _{3 - 6} alkanediol. At least one diol in the group, and selected from (b1') C _{3 - 6} alkanediol monoacetate, (b2) monoalkoxy-C _{3 - 6} alkanediol monoacetic acid At least one acetate in the group consisting of ester, (c1 ') C _{3 - 6} alkanediol diacetate, and (c2) monoalkoxy-C _{3 - 6} alkanediol diacetate a combination of the classes; (2) selected from the group consisting of (b1) C _{5 - 6} alkanediol monoacetate, and (b2) monoalkoxy-C _{3 - 6} alkanediol monoacetate At least one monoacetate, and selected from (c1') C _{3 - 6} alkanediol diacetate, and (c2) monoalkoxy-C _{3 - 6} alkanediol diacetate a combination of at least one diacetate in the group consisting of; (3) selected from (b1') C _{3 - 6} alkanediol monoacetate, and (b2) monoalkoxy-C _{3 - 6} At least one monoacetate in the group consisting of alkanediol monoacetates, and selected from (c1) C _{5 - 6} alkanediol diacetate, and (c2) monoalkoxy-C _3--6 alkane diol di A combination of at least one group of two acetates ester formed.

(a1), (a2), (b1), (b2), (c1), and (c2) are the same as described above. The (b1') C _{3 - 6} alkanediol monoacetate contains 1,2-propanediol monoacetate, 1,3-propanediol monoacetate, and 2, in addition to the solvent contained in (b1). -methyl-1,3-propanediol monoacetate, 1,2-butanediol monoacetate, 1,3-butanediol monoacetate, 1,4-butanediol monoacetate, etc. C _{3 - 4} alkane diol monoacetate. Further, the (c1') C _{3 - 6} alkanediol diacetate contains 1,2-propylene glycol diacetate and 1,3-propanediol diacetate in addition to the solvent contained in (c1). 2-methyl-1,3-propanediol diacetate, 1,2-butanediol diacetate, 1,3-butanediol diacetate, 1,4-butanediol diacetate other C _{3 - 4} alkane diol diacetate.

More specifically, two or more kinds of mixed solvents include 1,2-propanediol and 1,2-propylene glycol diacetate, 1,3-propanediol and 1,3-propanediol diacetic acid, and 1,3- Butanediol and 1,3-butanediol diacetate, 1,4-butanediol and 1,4-butanediol diacetate, 1,5-pentanediol monoacetate and 1, 5-pentanediol diacetate, 2-methyl-2,4-pentanediol and 2-methyl-2,4-pentanediol diacetate, 3-methoxy-1,2- A preferred mixed solvent of propylene glycol and 3-methoxy-1,2-propanediol diacetate. In particular, each of the diols having the same alkyl chain moiety is the same as the monoacetate or the alkyl chain, and the diacetate and the diacetate are the same as the diacetate and the alkyl chain. A mixed solvent is preferred.

C _{3 - 4} alkane diol monoacetate or C _{3 - 4} alkane diol diacetate alone can not be used, the former may be the above-mentioned esters or glycol diacetate, which with the above diol A combination of a class or a monoacetate.

As described above, when two or more organic solvents are used in combination, the ratio of the two may be appropriately selected depending on the type or purpose of the solvent. For example, in the case of the above (1), when a glycol is used in combination with an acetate (monoacetate and/or diacetate), the ratio of the two is the former/the latter (weight ratio) = 10/90 to 99/ 1, 40/60~95/5 is better, 50/50~90/10 is better, and 60/40~90/10 is especially good. Further, in the case of the above (2) or (3), when the monoacetate and the diacetate are used, the former/the latter (weight ratio) is 1/99 to 99/1, and the ratio is 10/90 to 90/10. Good, 20/80~80/20 is better, and 30/70~70/30 is especially good.

In the organic solvent of the present invention, other organic solvent (d) may be added (in combination) as long as the effects of the present invention are not impaired. Other organic solvents (d) which can be added include, for example, alkyl carboxylates and aliphatic ketones. The carboxylic acid esters may comprise for example alkyl lactate, an alkyl acetate, propionate, alkyl esters, alkoxylated alkyl esters of propionic acid having a hydroxyl group, an alkoxy group (e.g., C _{1 - 4} alkoxy An alkyl ester of an aliphatic carboxylic acid having a carbon number of from 1 to 4, such as a C _{1 - 6} alkyl ester, or the like.

More specific examples thereof include the lactic acid alkyl ester with a methyl lactate, ethyl lactate, etc. C _{1 - 6} alkyl esters, alkyl acetates have propyl acetate, n-butyl, n-amyl acetate and the like acetic acid C _{1 - 6} alkyl esters, alkyl propionate with a methyl propionate, ethyl propionate, propyl propionate, butyl propionate, C _{1 - 6} alkyl esters, alkoxy alkyl propionate, methyl methoxy propionate, ethyl ethoxy propionate, ethyl methoxypropionate, methyl ethoxypropionate, etc. C _{1 - 4} alkoxy acid C _{1 - 6} alkyl esters and the like. Further, examples of the aliphatic ketone include aliphatic ketones having a carbon number of about 3 to 10 such as 2-butanone, 2-pentanone, 2-hexanone and 2-heptanone.

Further, other organic solvents (d) which may be added include, in addition to the above, glycol ethers such as monopropylene glycol alkyl ether and dipropylene glycol alkyl ether; and monopropylene glycol alkyl ether acetate (propylene glycol methyl ether). Glycol ether acetates such as acetates and the like.

The amount of the other organic solvent (d) can be appropriately selected within a range that does not impair the solubility of the resin and other characteristics as a solvent for the photoresist, and is usually 80% by weight or less based on the total amount of the organic solvent in the resist composition. 70% by weight or less is more preferably 50% by weight or less, particularly preferably 10% by weight or less, and substantially 0% by weight.

In the photoresist composition of the present invention, the photoresist component may be any of conventionally known or known positive or negative photoresists. In the case of the representative photoresist which can be used in the present invention, for example, a quinone diazide-based sensitizer and an alkali-soluble resin, a chemically amplified photoresist, or the like may be mentioned, and a negative type may be mentioned. For example, it contains a polymer compound having a photosensitive group such as polyvinyl cinnamate, a substance containing an aromatic azide compound, or an azide containing a cyclized rubber and a biazide compound, and contains a heavy substance. A nitrogen resin, a photopolymerizable composition containing an addition polymer unsaturated compound, a chemically amplified negative photoresist composed of a soluble resin, a crosslinking agent, and an acid generator.

Preferred photoresist materials to be used in the present invention include those composed of a quinone diazide-based sensitizer and an alkali-soluble resin. Conventionally, various positive resists composed of a quinonediazide-based sensitizer and an alkali-soluble resin have been known, and are not particularly limited as long as they are any of the present invention.

In the case of an example of a quinonediazide sensitizer used for a positive photoresist composed of a quinone-based sensitizer and an alkali-soluble resin, for example, 1,2-benzoquinone diazide- 4-sulfonic acid, 1,2-naphthoquinonediazide-4-sulfonic acid, 1,2-naphthoquinonediazide-5-sulfonic acid, esters or amines of such sulfonic acids, and the like. The ester or amine compound of the sulfonic acid is obtained by subjecting the quinonediazidesulfonic acid or quinonediazidesulfonium chloride to a condensation reaction with a compound having a hydroxyl group or a compound having an amine group.

Examples of the compound having a hydroxyl group include dihydroxydiphenyl ketone, trihydroxydiphenyl ketone, tetrahydroxydiphenyl ketone, phenol, naphthol, p-methoxyphenol, bisphenol A, pyrocatechol, Pyrogallol, pyrogallol methyl ether, gallic acid, α , α', α"-gin (4-hydroxyphenyl)-1,3,5-triisopropylbenzene, cis (hydroxyphenyl) Further, examples of the compound having an amine group include aniline and p-aminodiphenylamine. These quinonediazide sensitizers may be used singly or in combination of two or more.

On the other hand, examples of the alkali-soluble resin include a resol resin, a polyvinyl phenol, a polyvinyl alcohol, a copolymer of acrylic acid or methacrylic acid, and the like.

Examples of the resol phenol resin include phenol, o-cresol, m-cresol, p-cresol, xylenol, trimethylphenol, t-butylphenol, ethylphenol, 2-naphthol, 1, A polycondensation product of one or more phenols such as 3-dihydroxynaphthalene and an aldehyde such as formaldehyde or polyoxymethylene. The alkali-soluble resin such as the resol phenol resin may be used in combination of two or more kinds as necessary, and other resins may be added in order to improve film formation properties and the like. Further, quinonediazide sulfonate (polyphenol condensate of phenols and aldehydes or ketones and ester of quinonediazidesulfonic acid) can also be used.

The ratio of the use of the quinonediazide-based sensitizer to the alkali-soluble resin is different depending on the sensitizer and the alkali-soluble resin to be used, and the weight ratio is usually in the range of 1:1 to 1:20, but it is preferable. The invention is not intended to be limited thereto.

Further, the chemically amplified photoresist is also a positive photoresist which can be suitably used in the present invention. The chemically amplified photoresist generates an acid by radiation irradiation, and a chemical change caused by the catalytic action of the acid changes a solubility of the radiation-irradiated portion in the developer to form a pattern, for example, which is generated by radiation irradiation. An acid generator-producing compound and an acid-sensitive group-containing resin which decomposes in the presence of an acid to form an alkali-soluble group such as a phenolic hydroxyl group or a carboxyl group.

The acid generating compound which generates the acid by the above-mentioned radiation irradiation may be, for example, a bisacetoguanidine diazomethane such as bis(isopropylsulfonium)diazomethane, or a disulfonium sulfonate such as methylsulfonyl p-toluenesulfonate methane. a methane class, such as a cyclohexylsulfonylcyclohexylcarbonyldiazomethane sulfonate carbonyldiazomethane, such as a 2-methyl-2-(4-methylphenylcarbonyl)propene benzene sulfonium alkane, Nitrobenzyl sulfonates such as 2-nitrobenzyl p-toluenesulfonate, alkyl or aryl sulfonates such as pyrogallol trimethanesulfonate, such as benzoin tosylate a benzoin sulfonate such as an N-sulfonyloxyimine of N-(trifluoromethylsulfonyloxy) ruthenium, such as (4-fluoro-benzenesulfonyloxy) -3,4,6-trimethyl-2-pyridone of this ketone, such as 2,2,2-trifluoro-1-trifluoromethyl-1-(3-vinylphenyl)-B The sulfonate of the 4-chlorobenzenesulfonate or the phosphonium salt of the triphenylsulfonium methanesulfonate may be used alone or in combination of two or more.

Further, an acid-sensitive group-containing resin which decomposes in the presence of an acid to form an alkali-soluble group such as a phenolic hydroxyl group or a carboxyl group is an acid-sensitive group which is decomposed in the presence of an acid, and a base having an alkali-soluble group. It consists of a soluble resin part. The acid-sensitive group may, for example, be a 1-branched methyl group such as a benzyl group, a 1-substituted ethyl group such as a 1-methoxyethyl group or a 1-benzylaminoethyl group, or a 1-branched alkyl group such as a tert-butyl group. a mercapto group such as a decyl group such as a trimethylsulfanyl group or a methoxyalkyl group such as a trimethylmethanealkyl group; an alkoxycarbonyl group such as a third butoxycarbonyl group; an alkyl group such as an ethenyl group; or a tetrahydropyran. A cyclic acid-decomposable group such as a tetrahydrofuranyl group, a tetrahydrothiopyranyl group or a tetrahydrothiophenyl group. Among these acid-decomposable groups, a benzyl group, a tert-butyl group, a tert-butoxycarbonyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a tetrahydrothiopyranyl group or a tetrahydrothiophenyl group is preferred.

The alkali-soluble resin having an alkali-soluble group such as a phenolic hydroxyl group or a carboxyl group may, for example, be hydroxystyrene, hydroxy- α -methylstyrene, hydroxymethylstyrene or carboxyadamantyl (meth)acrylate. , vinyl benzoic acid, carboxymethyl styrene, carboxymethoxy styrene, acrylic acid, methacrylic acid, crotonic acid, maleic acid, hexanoic acid, citraconic acid, mesaconic acid, cinnamic acid, etc. A polymer or copolymer of a vinyl monomer, a copolymer of at least one of these monomers with another monomer, a polycondensation resin such as a resol resin.

In addition to the above, the chemically amplified photoresist is also known to have a chemically amplified photoresist which is decomposed in the presence of an alkali-soluble resin, an acid generator, or an acid, so that the solubility control effect of the alkali-soluble resin can be lowered. Or a compound that promotes the solubility of an alkali-soluble resin. These can also be used.

These photoresist components can be dissolved in the above organic solvent to use the photoresist composition of the present invention. The ratio of the photoresist can be appropriately set depending on the type of the resist to be used and the type of the solvent, and is usually 50 to 3000 parts by weight, preferably 70 to 2000 parts by weight, per 100 parts by weight of the resist solid content, and is preferably used. 100 to 1000 parts by weight of an organic solvent is more preferable.

In particular, when 100 to 500 parts by weight of an organic solvent is used, most of the alkali solubility resin can exhibit high solubility.

Further, these photoresist compositions may be appropriately blended with various conventionally known additives in accordance with the purpose of use. If water is soluble, water can also be added for use.

The photoresist composition of the present invention can be used for various applications such as production of a semiconductor element or a liquid crystal display element, and is preferably used as a photoresist composition for producing a semiconductor or a liquid crystal display element. When the photoresist pattern is formed using the photoresist composition of the present invention, for example, it can be carried out as follows.

First, the photoresist composition of the present invention is prepared by dissolving a photoresist material in the above solvent, and the photoresist composition of the present invention thus obtained can be removed by filtration to remove insoluble matter as necessary. A conventionally known coating method such as spin coating, roll coating, reverse roll coating, cast coating, or blade coating is applied to a substrate such as ruthenium or glass so that the film thickness after prebaking is, for example, 0.01 to 1000 μm.

The photoresist composition coated on the substrate can be removed by, for example, prebaking on a hot plate to form a photoresist film. The prebaking temperature varies depending on the type of solvent or light to be used, and is usually 30 to 200 ° C, preferably at a temperature of about 50 to 150 ° C.

Exposure is carried out after the formation of the photoresist film, since exposure may be performed using an exposure source in accordance with the photosensitive range of the photoresist depending on the respective photosensitive ranges of the photoresist used. The exposure system uses a well-known illumination device such as a high pressure mercury lamp, a metal halide lamp, an ultrahigh pressure mercury lamp, a KrF excimer laser, an ArF excimer laser, an F2 laser, a soft X-ray irradiation device, an electron beam scanning device, etc., as necessary. The mask is placed in the middle and irradiated with a predetermined pattern shape using ultraviolet rays, far ultraviolet rays, X-rays, electron beams, or the like. After the exposure, in order to improve developability, resolution, pattern shape, and the like, post-baking may be performed as necessary, followed by development. Further, after development, dry etching may be performed by using a gas plasma or the like as necessary to remove an anti-reflection film or the like to form a pattern.

The development of the above-mentioned photoresist is usually carried out by using a developer and utilizing the solubility in an exposed region and an unexposed region or the difference in solubility in an alkali solution. As the alkaline developing solution, for example, an inorganic base such as sodium hydroxide, potassium hydroxide, sodium carbonate or sodium citrate, ammonia, ethylamine, diethylamine, triethylamine, diethylethanolamine or triethanolamine can be used. , amines such as benzylamine, amines such as formamide, tetramethylammonium hydroxide (TMAH), tetraethylamine hydroxide, choline, etc., ammonium salts, pyrrole, piperazine An aqueous solution or an aqueous solution obtained by dissolving a cyclic amine or the like.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited thereto.

Examples 1 to 6 and Comparative Examples 1 to 3 were esters of 1 molar 2,4,4,4'-tetrahydrophenylhydrazine with 3 moles of naphthoquinone-1,2-diazide-5-sulfonyl chloride. 2 g of the reaction product and 8 g of a cresol resole resin were dissolved in 40 g of a solvent having the composition shown in Table 1 (the ratio is a weight ratio) to prepare a coating liquid of the positive resist composition. The coatings thus obtained were subjected to the following evaluation tests (1) to (4). The results are shown in Table 1.

(1) The presence or absence of the precipitate was obtained by filtering the prepared coating liquid using a 0.2 μm membrane filter, and standing at 40 ° C. After 2 months, the presence or absence of precipitates in the coating liquid was examined.

(2) Sensitivity change The sensitivity of the photoresist composition for 3 months was changed. In other words, when the coating liquid immediately after preparation is applied to a substrate and dried, and the coating liquid after three months after preparation is applied onto a substrate and dried, the minimum exposure amount (sensitivity) is compared. The object with no change at all was evaluated as "○", and the object with reduced sensitivity was evaluated as "x".

(3) Cross-sectional shape The prepared coating liquid slit was coated on a glass substrate, and dried at 90 ° C for 90 seconds using a hot plate to form a photoresist film having a film thickness of 1.3 μm, and a predetermined mask was placed in the middle using a stepping machine. After exposing the film, it was heated at 110 ° C for 90 seconds on a hot plate, followed by using a 2.38 wt% aqueous solution of tetramethylammonium hydroxide (TMAH), washed with water for 30 seconds, and dried to observe the cross-sectional shape of the obtained resist pattern. According to the following benchmarks.

○: Undercut was not produced in the portion where the glass substrate and the photoresist pattern were in contact with each other.

×: An undercut was generated in a portion where the glass substrate and the photoresist pattern were in contact with each other. (Refer to Figure 1).

(4) Coating state The prepared coating liquid slit was applied onto a glass substrate, and dried at 90 ° C for 90 seconds using a hot plate, and the dried film thickness was measured. When the surface was uniformly coated, the film was evaluated as "good" and the surface was not uniform. It was evaluated as "poor" at the time of coating.

The singular numbers in the table are as follows. 1,3-MPGDA: 2-methyl-1,3 propylene glycol diacetate HG: 2-methyl-2,4-pentanediol HGDA: 2-methyl-2,4-pentanediol diacetic acid Ester GLMMA: 3-methoxy-1,2-propanediol monoacetate GLMDA: 3-methoxy-1,2-propanediol diacetate PGMEA: propylene glycol monomethyl ether acetate EL: ethyl lactate

Examples 7 to 8 and Comparative Example 4 copolymerized monohydroxyadamantyl acrylate with tetrahydropyranyl methacrylate to obtain monohydroxyadamantyl acrylate mono 70 mol% and tetrahydropyranyl methacrylate 30. Mole% by weight of a copolymer having a weight average molecular weight of 8,000. The solvent of the composition shown in Table 2 was added so that the solid content of the obtained resin was 25% by weight, and the mixture was heated at 50 ° C for 10 minutes, and the dissolution rate (solubility) of the resin was examined. The results are shown in Table 2, The number is the same as above.

○: homogeneous transparent solution.

×: A granular insoluble resin remained on the wall.

[Industry use possibility]

The photoresist composition of the present invention has excellent solvent solubility, is safe for human body, and is excellent in stability, and is useful as a photoresist composition for producing a semiconductor element or a liquid crystal display element.

1. . . glass substrate

2. . . Resistive pattern

3. . . Undercut

Fig. 1 is a schematic view showing a state in which an undercut is formed in the contact portion between the glass substrate and the resist pattern (evaluation: ×) in the cross-sectional shape evaluation test.

Claims (5)

A photoresist composition comprising a photoresist composition comprising a photoresist component and an organic solvent, wherein the organic solvent comprises a component selected from the group consisting of (a2) monoalkoxy-C _3-6 alkanediol, (b1)C _5-6 alkanediol monoacetate, (b2) monoalkoxy-C _3-6 alkanediol monoacetate, (c1) C _5-6 alkanediol diacetate, and (c2) A solvent of at least one of the group consisting of monoalkoxy-C _3-6 alkanediol diacetate. The photoresist composition of claim 1, wherein the organic solvent comprises at least one diol selected from the group consisting of (a2) monoalkoxy-C _3-6 alkanediol, and Free (b1') C _3-6 alkanediol monoacetate, (b2) monoalkoxy-C _3-6 alkanediol monoacetate, (c1 ') C _3-6 alkane A combination of at least one acetate in the group consisting of diol diacetate and (c2) monoalkoxy-C _3-6 alkanediol diacetate. The photoresist composition of claim 1, wherein the organic solvent comprises a compound selected from the group consisting of (b1) C _5-6 alkanediol monoacetate, and (b2) monoalkoxy-C _3-6 At least one monoacetate of the group consisting of alkanediol monoacetates, and selected from the group consisting of (c1') C _3-6 alkanediol diacetate, and (c2) monoalkoxy- A combination of at least one diacetate in the group consisting of C _3-6 alkanediol diacetates. The photoresist composition of claim 1, wherein the organic solvent comprises a compound selected from the group consisting of (b1') C _3-6 alkanediol monoacetate, and (b2) monoalkoxy-C _3- At least one monoacetate of the group consisting of ₆ alkanediol monoacetates, and selected from the group consisting of (c1) C _5-6 alkanediol diacetate, and (c2) monoalkoxy- A combination of at least one diacetate in the group consisting of C _3-6 alkanediol diacetates. The photoresist composition according to any one of claims 1 to 4, further comprising at least one solvent selected from the group consisting of alkyl carboxylates and aliphatic ketones as an organic solvent.