JPH0829977A - Positive type resist c0mposition - Google Patents

Abstract

PURPOSE:To provide the positive type photosensitive composition, which can prevent the generation of halation without hindering sensitivity, resolution and residual film ratio. CONSTITUTION:This positive type resist composition contains alkali soluble phenol resin (a), 1,2-naphthoquinonediazide sulfonic acid ester (b) of the compound having dibendzylideneaceton framework. In the formula, R<1>-R<10> mean hydrogen atom, halogen atom, hydroxyl group, alkyl group, aryl group, alkenyl group, alkinyl group, amino group, nitro group, cyano group, alkoxy group, acetyl group, 1, 2-naphthoquinonediazide-5-sulfonyl group, and they can be the same one or they can be different from each other, and at least of them means hydroxyl group. R<11>-R<12> mean hydrogen atom, alkyl group and aryl group, and they can be the same one or they can be different from each other.

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, and more particularly to a positive resist composition for microfabrication required for manufacturing semiconductor devices, magnetic bubble memory devices, integrated circuits and the like. .

[0002]

2. Description of the Related Art When manufacturing a semiconductor, a resist is coated on the surface of a silicon wafer to form a photosensitive film, which is irradiated with light to form a latent image, which is then developed to form a negative or positive image. A semiconductor element is formed by a lithographic technique. Conventionally, as a resist composition for forming a semiconductor element, a positive resist composed of an alkali-soluble resin and a quinonediazide compound has been widely used because of its excellent resolution. Further, the improvement of the performance of the positive resist and the improvement of the performance of the exposure device have improved the resolution, and it has become possible to form a fine pattern of 1 μm or less.

However, this positive type resist has a drawback that the resolution is lowered on a thin film (hereinafter referred to as a substrate) such as aluminum and chrome for a photomask having a high light reflectance used for manufacturing a silicon semiconductor device. are doing. That is, at the time of exposure, after the light passing through the transparent portion of the mask exposes the positive resist, the light is reflected by the substrate and wraps around to the area of the positive resist under the light shield, which is not desired to be exposed. The so-called halation phenomenon of exposing to light occurs, and as a result, there are problems that the resolution is lowered and the pattern shape becomes thinner than a desired size.

For the purpose of improving this drawback, Japanese Patent Publication No. 51-
The method described in Japanese Patent No. 37562 has been proposed.
This method is intended to reduce the light transmittance in the resist composition film by adding a light absorbing material such as oil yellow to the resist composition. However, when such a resist composition is used, it is volatilized from the resist composition film during prebaking, so that the antihalation effect is impaired, sensitivity is lowered, pinholes are formed, and the resist film is formed. However, there are drawbacks such as a decrease in the adhesion between the substrate and the substrate, various characteristics such as sensitivity, pattern shape, resolution, and residual film rate are impaired, and the overall performance as a resist is insufficient.

[0005]

DISCLOSURE OF THE INVENTION Under the above-mentioned conventional techniques, the inventors of the present invention have made diligent studies to obtain an antihalation agent that does not impair the resist properties. As a result, a compound having a dibenzylideneacetone skeleton, naphthokindiazide is obtained. It was found that the use of sulfonic acid ester as a photosensitizer can prevent halation without impairing the sensitivity, resolution and residual film rate, and has completed the present invention.

[0006]

Thus, according to the present invention, an alkali-soluble phenol resin (a) and the following general formula (I)

Embedded image (R ^{1 to} R ¹⁰ may be the same or different from each other, and each represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, an amino group, a nitro group, a cyano group, an alkoxy group or an acetyl group. And at least one is a hydroxyl group. R ^{11 to} R ¹² may be the same or different from each other and are a hydrogen atom, an alkyl group or an aryl group.) 1, 2 of the compound having a dibenzylideneacetone skeleton. -A positive resist composition characterized by containing a naphthoquinone diazide sulfonic acid ester (b), and a positive resist composition characterized by further containing a low molecular weight phenol compound in the composition. Will be provided. Hereinafter, the present invention will be described in detail.

Examples of the alkali-soluble phenol resin used in the present invention include condensation reaction products of phenols and aldehydes, condensation reaction products of phenols and ketones, vinylphenol polymers, isopropenylphenol resins. Polymers, hydrogenation reaction products of these phenolic resins and the like can be mentioned. Specific examples of the phenols used here include monovalent phenols such as phenol, cresol, xylenol, ethylphenol, propylphenol, butylphenol and phenylphenol; resorcinol, pyrocatechol,
Examples include polyphenols such as hydroquinone, bisphenol A, phloroglucinol, and pyrogallol. Specific examples of aldehydes include formalin, paraformaldehyde, acetaldehyde, benzaldehyde, terephthalaldehyde and the like. Specific examples of ketones include acetone, methyl ethyl ketone,
Examples thereof include diethyl ketone and diphenyl ketone.
These condensation reaction products can be obtained by a conventional method, for example, by reacting phenols with aldehydes or ketones in the presence of an acidic catalyst.

The vinylphenol-based polymer is selected from a homopolymer of vinylphenol and a copolymer of vinylphenol and a component copolymerizable with vinylphenol. The isopropenylphenol-based polymer is a polymer of isopropenylphenol. It is a homopolymer or a copolymer of a component capable of copolymerizing with isopropenylphenol. Specific examples of components copolymerizable with vinylphenol and isopropenylphenol include acrylic acid, methacrylic acid, styrene,
Examples thereof include maleic anhydride, maleic imide, vinyl acetate, acrylonitrile, and their derivatives. The copolymer can be obtained by a known method.

The hydrogenation reaction product of the phenolic resin is
It can be obtained by a conventional method, for example, by dissolving the above-mentioned phenol resin in an organic solvent and hydrogenating in the presence of a homogeneous or heterogeneous catalyst.

These alkali-soluble phenolic resins can be used by controlling the molecular weight and the molecular weight distribution by known means. As a method for controlling the molecular weight and the molecular weight distribution, the resin is crushed and solid-liquid extracted with an organic solvent having an appropriate solubility, or the resin is dissolved in a good solvent and added dropwise to a poor solvent, or a poor solvent. And a solid-liquid or liquid-liquid extraction method may be mentioned.

These alkali-soluble phenolic resins can be used alone or in a mixture of two or more kinds. In the positive resist composition of the present invention, if necessary, in order to improve developability, storage stability, heat resistance, etc., a copolymer of styrene and acrylic acid, methacrylic acid or maleic anhydride, an alkene and A copolymer with maleic anhydride, a vinyl alcohol polymer, a vinylpyrrolidone polymer, rosin, shellac and the like can be added. The upper limit of the amount of these additives added is usually 50 parts by weight, preferably 20 parts by weight, and the lower limit is usually 0 parts by weight, preferably 5 parts by weight, based on 100 parts by weight of the alkali-soluble phenol resin.

The photosensitizer used in the present invention is a 1,2-naphthoquinonediazide sulfonic acid ester of a compound having the dibenzylideneacetone skeleton represented by the general formula (I) (hereinafter referred to as the photosensitizer of the present invention). is there)
However, in addition to this, a compound which has been conventionally used as a photosensitizer (hereinafter, also referred to as a general photosensitizer) may be used in combination. When two or more photosensitizers are used in combination, the amount of the photosensitizer of the present invention is 5% of the total amount of the photosensitizer.
The above can be used together in the range of preferably 20% or more.

The compound having a dibenzylideneacetone skeleton represented by the above formula (I) has the formula (II)

Embedded image (R ¹³ and R ¹⁴ may be the same or different from each other,
A hydrogen atom, an alkyl group, and an aryl group. ) Is represented by the formula (III):

[Chemical 4] (R ^{15 to} R ¹⁹ may be the same as or different from each other, and each represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, an amino group, a nitro group, a cyano group, an alkoxy group or an acetyl group. And at least one is a hydroxyl group.) It can be obtained by subjecting two molecules of an aromatic aldehyde represented by () to a condensation reaction in the presence of a catalyst according to a conventional method. In this reaction, one kind of aromatic aldehyde is usually used, but two kinds of aromatic aldehydes can be used if desired. When two kinds of aromatic aldehydes are used, the two kinds of aromatic aldehydes may be simultaneously subjected to a condensation reaction, or the two kinds of aromatic aldehydes may be separately added stepwise to cause the condensation reaction. . Examples of the catalyst used in this reaction include acid catalysts such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, acetic anhydride, p-toluenesulfonic acid and methanesulfonic acid, and sodium hydroxide, potassium hydroxide, sodium methoxide and sodium ethoxy. Examples include basic catalysts such as potassium and potassium tert-butoxide, which are appropriately selected depending on the reactivity between the ketones and aldehydes used.

The compound having a dibenzylideneacetone skeleton thus obtained is esterified by a conventional method, for example, by reacting it with a naphthoquinonequinonediazide sulfonic acid halide to give the photosensitizer of the present invention. This reaction is usually carried out using dioxane, acetone, tetrahydrofuran or the like as a solvent in the presence of a base catalyst such as triethylamine, pyridine, sodium carbonate, sodium hydrogen carbonate, sodium hydroxide or potassium hydroxide.
Specific examples of naphthoquinone diazide sulfonic acid include:
1,2-naphthoquinonediazide-2-sulfonic acid, 1,
2-naphthoquinonediazide-3-sulfonic acid, 1,2-
Examples thereof include naphthoquinonediazide-4-sulfonic acid, 1,2-naphthoquinonediazide-5-sulfonic acid, and 1,2-naphthoquinonediazide-6-sulfonic acid, and preferably 1,2-naphthoquinonediazide-4-sulfone. An acid and 1,2-naphthoquinonediazide-5-sulfonic acid, which are usually reacted with a halogenated sulfonic acid such as chlorosulfonic acid and then used as a sulfonyl halide. In the photosensitizer of the present invention thus obtained, all the hydroxyl groups of the compound having a dibenzylideneacetone skeleton do not necessarily have to be esterified, and the esterification rate is usually selected from 1 to 100%. However, the lower limit is preferably 70% and the upper limit is 100%.

Specific examples of the photosensitizer of the present invention include the compounds listed in Tables 1 and 2. In addition, R ^{1 in} the table
~ R ¹² corresponds to the above formula (I).

[0016]

[Table 1]

[0017]

[Table 2]

The general photosensitizer which is optionally used in combination with the photosensitizer of the present invention is not particularly limited as long as it is an ester compound of a hydroxy compound and quinonediazide sulfonic acid, which is usually used as a photosensitizer. The hydroxy compound used here is a known one having a phenolic hydroxyl group, and specific examples include 2,3,4-
Trihydroxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,4,2 ', 4'-tetrahydroxybenzophenone, 2,3,4,2' , 4'-
Polyhydroxybenzophenones such as pentahydroxybenzophenone; gallic acid esters such as methyl gallate, ethyl gallate, propyl gallate; 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (2,4) -Polyhydroxybisphenylalkanes such as dihydroxyphenyl) propane; tris (4-hydroxyphenyl) methane, tris (4-hydroxy-3-)
Methylphenyl) methane, 1,1,1-tris (4-hydroxy-3-methylphenyl) ethane, 1,1,1-
Tris (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxy-3-methylphenyl) -1- (4
-Hydroxyphenyl) ethane, bis (4-hydroxy-3-methylphenyl) -2-hydroxy-4-methoxyphenylmethane, and other polyhydroxytrisphenylalkanes; 1,1,2,2-tetrakis (4-hydroxyphenyl) ) Ethane, 1,1,2,2-tetrakis (3
-Methyl-4-hydroxyphenyl) ethane, 1,1,
Polyhydroxytetrakisphenylalkanes such as 3,3-tetrakis (4-hydroxyphenyl) propane;
α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -3-xylene, α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -4-xylene, α,
Polyhydroxytetrakisphenylxylenes such as α, α ′, α′-tetrakis (3-methyl-4-hydroxyphenyl) -3-xylene; 2,6-bis (2,4-dihydroxybenzyl) -p-cresol, 2,6-bis (2,4-dihydroxy-3-methylbenzyl) -p-
Cresol, 4,6-bis (4-hydroxybenzyl)
Resorcin, 4,6-bis (4-hydroxy-3-methylbenzyl) resorcin, 4,6-bis (4-hydroxybenzyl) -2-methylresorcin, 4,6-bis (4-hydroxy-3-methylbenzyl) ) A trimer of phenols such as 2-methylresorcin and formalin.

These are reacted with a quinonediazidesulfonic acid compound according to a conventional method to give 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-ester. 5-sulfonic acid ester, 2,1-naphthoquinonediazide-4-sulfonic acid ester, 2,1-
By using naphthoquinone diazide-5-sulfonic acid ester, a general photosensitizer usable in the present invention can be obtained.

The amount of the photosensitizer used in the present invention (as a photosensitizer combining the photosensitizer of the present invention and a general photosensitizer) is 100% of the alkali-soluble phenol resin (a).
1 to 100 parts by weight, preferably 3 parts by weight
~ 40 parts by weight. If the amount is less than 1 part by weight,
It becomes difficult to form a pattern, and if it exceeds 100 parts by weight, the sensitivity is lowered and the undeveloped portion is likely to occur.

Furthermore, in the resist composition of the present invention, the alkali solubility of the alkali-soluble phenol resin is increased,
For the purpose of improving sensitivity, residual film rate, resolution and heat resistance,
A low molecular weight phenolic compound can be added. The low molecular weight phenol compound used in the present invention has a molecular weight of 1,
The molecular weight is preferably 7,000 or less, but is preferably 700 or less. Specific examples of the low molecular weight phenol compound include p-phenylphenol,
Monophenols such as p-isopropylphenol; biphenol, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxybenzophenone, bisphenol-A, bisphenol-C, bisphenol-
E, bisphenol-F, bisphenol-AP, bisphenol-M, bisphenol-P, bisphenol-Z, 1,1-bis (4-hydroxyphenyl) cyclopentane, 9,9-bis (4-hydroxyphenyl) fluorene, 1 , 1-bis (5-methyl-2-hydroxyphenyl) methane, 1,1-bis (3,5-dimethyl-
Bisphenols such as 4-hydroxyphenyl) methane; 1,1,1-tris (4-hydroxyphenyl) methane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) -1- (2-hydroxy Trisphenolalkanes such as phenyl) methane and 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) -1- (2-hydroxyphenyl) methane, 2,6-bis (5-
Methyl-2-hydroxyphenyl) -4-methylphenol, 2,6-bis (4-methyl-2-hydroxyphenyl) -4-methylphenol, 2,6-bis (4-hydroxybenzyl) -4-methylphenol , 2,6-
Bis (3-methyl-4-hydroxybenzyl) -4-methylphenol, 2,6-bis (3,5-dimethyl-4)
-Hydroxyphenyl) -4-methylphenol and other trinuclear phenols; α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -3-xylene, α,
Tetrakisphenols such as α, α ′, α′-tetrakis (4-hydroxyphenyl) -4-xylene, α, α, α ′, α′-tetrakis (3-methyl-4-hydroxyphenyl) -3-xylene Α, α, α′-tris (4-hydroxyphenyl) -α, α ′, α′-trimethyl-p-xylene (hereinafter referred to as trisphenol PA) and the like are exemplified. Among these, bisphenol Z, 1,1-bis (4-hydroxyphenyl) cyclopentane, α, α, α ′, α′-tetrakis (4-hydroxyphenyl) -4-xylene and trisphenol P.
A is a preferred example. The addition amount of such a low molecular weight phenol compound depends on the composition of the alkali-soluble phenol resin, the molecular weight, the molecular weight distribution, and the type and amount of other additives, but the upper limit is 100 parts by weight of the alkali-soluble phenol resin. Usually 100 parts by weight, preferably 6
0 parts by weight, the lower limit is usually 1 part by weight, preferably 3 parts by weight.

The positive resist composition of the present invention is usually used by dissolving it in a solvent to apply it to a substrate to form a resist film. Specific examples of the solvent that can be used in the present invention include ketones such as acetone, methyl ethyl ketone, and cyclopentanone; alcohols such as n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, and cyclohexanol; ethylene glycol dimethyl ether. , Ethers such as ethylene glycol diethyl ether, dioxane; alcohol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether; propyl formate, butyl formate, propyl acetate, butyl acetate, methyl propionate,
Esters such as ethyl propionate, methyl butyrate, ethyl butyrate, methyl lactate, ethyl lactate; cellosolve acetates such as cellosolve acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propyl cellosolve acetate, butyl cellosolve acetate; propylene glycol, propylene glycol monomethyl ether Propylene glycols such as acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether; diethylene glycols such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether; halogenated hydrocarbons such as trichloroethylene Toluene, aromatic hydrocarbons such as xylene; dimethylacetamide, dimethylformamide, such as a polar solvent such as N- methyl acetamide and the like, which may be used by either singly or in combination.

The positive resist composition of the present invention may contain compatible additives such as a surfactant, a storage stabilizer, a sensitizer, a striation inhibitor and a plasticizer, if necessary. it can.

The developer suitable for the positive resist composition of the present invention is an alkaline aqueous solution, and specific examples thereof include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium silicate and ammonia; ethylamine. , Primary amines such as propylamine; secondary amines such as diethylamine and dipropylamine; tertiary amines such as trimethylamine and triethylamine; N, N
Alcohol alcohols such as dimethylmethanolamine and triethanolamine; tetramethylammonium hydroxide, tetraethylammonium hydroxide,
Examples thereof include aqueous solutions of quaternary ammonium salts such as triethylhydroxymethylammonium hydroxide and trimethylhydroxyethylammonium hydroxide. Further, if necessary, the alkaline aqueous solution,
A water-soluble organic solvent such as methanol, ethanol, propanol, or ethylene glycol, a surfactant, a storage stabilizer, a resin dissolution inhibitor, and the like can be appropriately added.

Preferred embodiments of the present invention will be described below. (1) A positive resist composition comprising an alkali-soluble phenolic resin and a photosensitizer, which is a naphthoquinone diazide sulfonic acid ester of a compound having a dibenzylideneacetone skeleton represented by the general formula (I) as at least the photosensitizer ( A positive resist composition containing b) in an amount of 5% by weight or more based on the total amount of the photosensitizer. (2) Alkali-soluble phenol resin (a), dibenzylideneacetone represented by the general formula (b-1), (b-2), (b-3), (b-4) and (b-5). A positive resist composition comprising a naphthoquinone diazide sulfonate (b) which is a compound selected from the group consisting of compounds having a skeleton. (3) Alkali-soluble phenol resin (a), dibenzylideneacetone represented by the general formulas (b-1), (b-2), (b-3), (b-4) and (b-5). A positive resist composition comprising a naphthoquinone diazide sulfonate (b), which is a compound selected from the group consisting of compounds having a skeleton, in an amount of 5% by weight or more based on the total amount of the photosensitizer.

[0026]

【Example】

(Synthesis Example 1) Synthesis of Novolac Resin a-1 A 2 liter flask equipped with a cooling pipe and a stirrer was
356 g of m-cresol, 356 g of p-cresol, 3
330% 7% formalin and oxalic acid dihydrate 2.49
g was charged, and the reaction was carried out for 2 hours while maintaining the temperature at 95 to 100 ° C. Then, the water was distilled off at 100 to 105 ° C. for 2 hours, and the temperature was raised to 180 ° C. to 10 mm.
After reducing the pressure to Hg to remove unreacted monomers and water, the temperature was returned to room temperature and recovered, and the novolak resin a-1 was added to
0 g was obtained. The weight average molecular weight of the novolak resin a-1 in terms of polystyrene measured by gel permeation chromatography (hereinafter referred to as GPC) was 6400.

(Synthesis Example 2) Synthesis of 4,4'-dihydroxybenzalacetone and synthesis of photosensitizer b-1 In a 1 liter three-necked flask equipped with a stirrer and a thermometer, 59 g of potassium hydroxide and 100 ml of water were added. And ethyl alcohol were dissolved in a mixed solvent of 300 ml and the temperature was adjusted to 20 to 25 ° C. A mixture of 36 g of p-hydroxybenzaldehyde and 9 g of acetone was added to this potassium hydroxide over 30 minutes while maintaining the reaction temperature. After stirring at 25 ° C. for 4 hours, the mixture was treated according to a conventional method to obtain a crude product. The crude product was purified by recrystallization from a mixed solvent of ethyl acetate and n-hexane to obtain 16 g of 4,4'-dihydroxybenzalacetone. The ultraviolet spectrum of this compound was λ _MAX = 351 nm. Using 4,4'-dihydroxybenzalacetone thus obtained, 1,2-naphthoquinonediazide-5-sulfonic acid chloride in an amount corresponding to 80% of the hydroxyl groups of this compound was dissolved in acetone to give 10 % Solution. While controlling the temperature so that it is in the range of 20 to 25 ° C,
Toluethylamine (1.2 equivalents of 1,2-naphthoquinonediazide-5-sulfonic acid chloride) was added dropwise over 30 minutes, the reaction temperature was maintained for 2 hours, and the precipitated salt was filtered off. 0.2 times 10 times the equivalent of the reaction solution
% Oxalic acid aqueous solution was added, and the precipitated solid content was filtered off, washed with ion-exchanged water, and dried to give a quinonediazide sulfonic acid ester-based photosensitizer b-1 (esterification rate 80
%)Obtained.

(Synthesis Examples 3 to 6) Synthesis of Photosensitizers b-2 to b-5 As dibenzylideneacetone, 2,4'-dihydroxybenzylideneacetone, 2,2'-dihydroxybenzylideneacetone, 2,2, '4 was used. -A photosensitizer was obtained in the same manner as in Synthesis Example 2 except that trihydroxybenzylideneacetone and 2,2 ', 3,3'-tetrahydrobenzylideneacetone were used. Hereinafter, the obtained photosensitizers are referred to as b-2, b-3, b-4 and b-5 (all esterification rate = 80%).

The resist evaluation methods in the following examples and comparative examples are as follows. All resist evaluations were performed on aluminum stepped substrates. (1) Sensitivity A value that represents the amount of exposure energy that can form a 1: 1 line and space having a sensitivity of 0.60 μm according to the design dimension in terms of exposure time. (2) Resolution This represents the limit resolution (μm) under the above exposure conditions. (3) Pattern shape A result of forming a resist film having a thickness of 2.04 μm, exposing and developing to process the pattern, and observing the thinning of the pattern and the pattern shape is shown.

Example 1 In the ethyl lactate solution of resin a-1 obtained in Synthesis Example 1, the photosensitizer b-1 obtained in Synthesis Example 2 was dissolved in 3% by weight based on the solid content. This solution was spin-coated on a quartz glass plate. This is baked at 110 ° C. for 20 minutes, and then it is baked with an ultraviolet-visible spectrometer for 3 minutes.
The change in absorbance at 65 nm before and after baking was measured. The absorbance ratio before and after baking (absorbance after baking / absorbance before baking) was 0.99.

Example 2 A test was conducted in the same manner as in Example 1 except that the photosensitizers b-2, b-3, b-4 and b-5 obtained in Synthesis Examples 3 to 6 were used as photosensitizers. went.
As a result, the absorbance ratio was 0.99 regardless of which photosensitive agent was used.

Comparative Example 1 A test was conducted in the same manner as in Example 1 except that Oil Yellow (trade name) was used as the photosensitizer, and the absorbance ratio was 0.89. From Examples 1 and 2 and Comparative Example 1, it is found that the resist composition of the present invention is excellent in sublimation resistance and is excellent in stability without deterioration or variation in antihalation effect due to sublimation of the light absorber during prebaking. It was

(Examples 3 to 7) A resist composition having the composition (unit: parts by weight) shown in Table 1 (as a general photosensitizer, tris (4-hydroxyphenyl) methane 1,2) was used.
-Naphthoquinone diazide-5-sulfonic acid ester (esterification rate = 90% was used) and trisphenol PA as a phenol compound were dissolved in ethyl lactate, and the solvent content was adjusted so that a coating of 2.04 μm was obtained. Prepared. These solutions were filtered with a 0.1 μm Teflon filter (polytetrafluoroethylene filter) to prepare a resist solution. After coating the above resist solution on an aluminum step substrate with a coater,
Pre-baking was performed for 2 seconds to form a resist film having a film thickness of 2.04 μm. This wafer is i-line stepper NSR175
5i7A (manufactured by Nikon Corporation, NA = 0.50) and a test reticle were used for exposure while varying the exposure time, and then post-exposure bake (Post Ex for 60 seconds at 110 ° C.).
pose baking) was performed. Then 2.3
A positive pattern was formed by developing with an 8% aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 1 minute by the paddle method. This wafer was taken out and observed with an electron microscope, the resolution and the pattern dimension were measured, and the resist was evaluated.

Comparative Example 2 A positive type pattern was formed in the same manner as in Example 3 except that the photosensitizer of the present invention was not added, and resist evaluation was carried out. The results of Examples 3 to 7 and Comparative Example 2 are shown in Table 3.

[0035]

[Table 3]

From the results of the above Examples and Comparative Examples, it was found that a resist pattern excellent in sensitivity, resolution and pattern shape can be obtained by using the resist composition of the present invention.

[0037]

According to the present invention, a resist composition capable of preventing halation without impairing sensitivity, resolution and residual film rate can be obtained and is useful as a positive resist for fine processing.

Claims (2)

[Claims] 1. An alkali-soluble phenolic resin (a),
And a 1,2-naphthoquinonediazide sulfonic acid ester (b) of a compound having a dibenzylideneacetone skeleton represented by the following general formula (I), which is a positive resist composition. Embedded image (R ^{1 to} R ¹⁰ may be the same or different from each other, and are a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, an amino group, a nitro group, a cyano group, an alkoxy group, an acetyl group, 1,2-naphthoquinonediazide-5-sulfonyl group, at least one of which is a hydroxyl group, and R ^{11 to} R ¹² may be the same or different from each other and are a hydrogen atom, an alkyl group or an aryl group.) 2. The positive resist composition according to claim 1, further comprising a low molecular weight phenol compound.