JPH02244052A - Resist pattern forming method - Google Patents

Abstract

PURPOSE:To easily obtain a high-contrast resist pattern having high resolution and sharp pattern profile by bringing a resist layer into contact with an aq. soln. of a quat. ammonium salt before development. CONSTITUTION:When a resist layer is formed on a substrate with a radiation- sensitive resin compsn. contg. alkali-soluble resin and a resist pattern is formed by irradiating and developing the resist layer, the resist layer is brought into contact with an aq. soln. of a quat. ammonium salt before development. A compd. represented by formula I may be used as the quat. ammonium salt. In the formula I, each of R<1>-R<4> is 1-30C alkyl such as methyl or ethyl, 6-30C aryl, etc., and X<-> is a halogen anion such as Cl<->, Br<-> or F<-> or an anion such as BF4<-> or ClO4<->. A high-contrast resist pattern having high resolution and sharp pattern profile is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for forming a resist pattern, and more particularly to a method for forming a resist pattern using a radiation-sensitive resin composition containing an alkali-soluble resin.

[Conventional technology]

A positive resist consisting of an alkali-soluble resin and a 1,2-quinonediazide compound has a 1,2-
The quinonediazide compound changes to indenecarboxylic acid and becomes soluble in a developer consisting of an alkaline aqueous solution, but 1.2% of the unirradiated area, which becomes the resist pattern,
- The quinonediazide compound does not change and therefore does not dissolve in the developer. Therefore, the positive resist has very little deformation in the non-irradiated portions after development, and provides a resist pattern that is faithful to the mask and has high resolution.

In recent years, when integrated circuits are required to have a higher degree of integration, the above-mentioned positive resists are often used.
In particular, further improvements in resolution, pattern profile, and contrast are desired.

As a method for improving the resolution, contrast, pattern profile, etc. in response to the above-mentioned demands, a method of irradiating the resist with radiation and then irradiating the entire surface with deep ultraviolet rays without heating it (Y, Okuda et al.).

SPME, 777.61 (1987)), or a method of immersion in an alkaline developer after forming a resist layer and before exposure (Endo et al., 1st Micro Proc.
ess Conf, p. 164 (1988)), but the former method has disadvantages such as the need for additional deep ultraviolet irradiation equipment and an increase in control factors in the manufacturing process compared to the conventional method. The latter method requires immersion treatment before exposure, which has drawbacks such as the need to add new development line equipment.

[Problem to be solved by the invention]

An object of the present invention is to provide a method for forming a resist pattern that eliminates the drawbacks of the prior art and that can easily obtain a resist pattern with high resolution, high contrast, and an excellent pattern profile without adding new equipment. It is about providing.

[Means to solve the problem]

In the method for forming a resist pattern of the present invention, a resist layer is formed on a substrate using an irradiation resin composition containing an alkali-soluble resin, the resist layer is irradiated with radiation, and then developed to form a resist pattern. When forming the resist layer, the resist layer is brought into contact with an aqueous solution of a quaternary ammonium salt before the resist layer is developed.

Examples of the quaternary ammonium salt used in the present invention include compounds represented by the following formula (I).

(In the formula, R1, R2, R3 and R4 are the same or different C, -C such as methyl group, ethyl group, propyl group)
,. C6-C3 aryl group such as phenyl group, naphthyl group, tolyl group, xylyl group, C's-C3 degree alkenyl group such as allyl group, 2-methylallyl group, benzyl group, methylbenzyl group etc.07
~C3° aralkyl group, X- is chlorine, bromine,
Halogen anions such as fluorine, iodine 5 or BF4
-, CIO.

Br04- 104- , Re04- , N0zH2
F: l −, FSOi −, 8g3C1m −, Hg:
Among the quaternary ammonium salts represented by the - setting (1) above, lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, cetyltrimethylammonium chloride, cyatearyltrimethylammonium chloride, benzene Preferably used are ruconium ammonium chloride, lauryldimethylbenzylammonium chloride, laurylisoquinolium bromide, and the like.

The quaternary ammonium salt is used after being dissolved in water, and the concentration of quaternary ammonium at that time is 0.1 to 5.
00. It is preferably OOOppm, more preferably 0.5 to 500 ppm. This concentration is o,
If it is less than i p p m, it may not be possible to obtain a pattern with high resolution, high contrast, and an excellent pattern profile, and if it exceeds 500°000 ppm, the resist pattern may become overhanging or residual development (scum) may occur. This may occur.

Methods for bringing an aqueous solution of a quaternary ammonium salt into contact with a resist layer include a method in which a substrate provided with a resist layer is immersed in an aqueous solution of a quaternary ammonium salt, and a method in which an aqueous solution of a quaternary ammonium salt is placed on a resist layer. Examples include methods to do so. The contact time between the quaternary ammonium salt and the resist layer is usually about several tens of seconds to several minutes, and the temperature of the quaternary ammonium salt is usually room temperature.

In the present invention, typical alkali-soluble resins included in the radiation-sensitive resin composition include alkali-soluble novolak resins (hereinafter simply referred to as "novolak resins") and hydroxystyrene resins.

Novolac resins are obtained by polycondensing phenols and aldehydes in the presence of an acid catalyst.

Examples of phenols include phenol, 〇-cresol, m-cresol, p-cresol, 〇-ethylphenol, m-ethylphenol, p-ethylphenol, 0-butylphenol, m-butylphenol, P
-butylphenol, 2,3-xylenol, 2,4-
Xylenol, 2,5-xylenol, 3.4-xylenol, 3.5-xylenol, 2,3.5-)limethylphenol, p-phenylphenol, hydroquinone, catechol, resorcinol, 2-methylresorcinol, pyrogallol, α - Naphthol, bisphenol A, dihydroxybenzoic acid ester, gallic acid ester, etc. are used. Among these, phenol, O-cresol, m-cresol, p-cresol, 2.5-xylenol, 3.5-xylenol, 2,3.5-)limethylphenol, resorcinol, 2-methylresorcinol and bisphenol A are preferable. These phenols may be used alone or in combination of two or more.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propylaldehyde, benzaldehyde, phenylacetaldehyde,
α-phenylpropylaldehyde, β-phenylpropylaldehyde, 〇=Hydroxybenzaldehyde, m-
Hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, O-nitrobenzaldehyde, m-nitrobenzaldehyde,
p-Nitrobenzaldehyde, 0-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, p-ethylbenzaldehyde, p-n-butylbenzaldehyde, etc. are used. Among these, formaldehyde, acetaldehyde and benzaldehyde are preferred. These aldehydes may be used alone or in combination of two or more.

The aldehyde is preferably used in a proportion of 0.7 to 3 mol, particularly preferably 0.7 to 2 mol, per mol of phenol.

As the acid catalyst, for example, inorganic acids such as hydrochloric acid, nitric acid, and sulfuric acid, or organic acids such as formic acid, oxalic acid, and acetic acid are used.

The amount of these acid catalysts used is preferably 1X10-' to 5X10'-' moles per mole of phenol.

In condensation reactions, water is usually used as the reaction medium, but if the phenols used in the condensation reaction do not dissolve in the aqueous solution of aldehydes and the reaction becomes a heterogeneous system from the early stage, water may be used as the reaction medium. Solvents can also be used. Examples of these hydrophilic solvents include alcohols such as methanol, ethanol, propatool, and butanol, and cyclic ethers such as tetrahydrofuran and dioxane. The amount of these reaction media used is usually 20 to 10 parts by weight per 100 parts by weight of reaction materials.
00 parts by weight.

The reaction temperature of the condensation reaction can be adjusted as appropriate depending on the reactivity of the reaction raw materials, but is usually 10 to 200°C, preferably 70 to 150°C.

After the condensation reaction is complete, the indoor hot water is generally heated to 130 ml to remove unreacted raw materials, acid catalysts, and reaction media present in the system.
The temperature is increased to ˜230° C. and the volatiles are distilled off under reduced pressure. Further, after the condensation reaction is completed, the reaction mixture is dissolved in the hydrophilic solvent, and the novolac resin is precipitated by adding it to a precipitant such as water, n-hexane, or n-heptane, and the precipitate is separated and collected. You can also do it.

The weight average molecular weight of novolak resin in terms of polystyrene is
Usually 2,000 to 30,000, preferably 4,000
0 to 25,000.

Examples of hydroxystyrene resins include hydroxystyrene, α-methyl-m-hydroxystyrene,
At least one polymer selected from hydroxystyrene and hydroxystyrene derivatives such as α-methyl-p-hydroxystyrene; hydroxystyrene and/or
or hydroxystyrene copolymers such as copolymers of hydroxystyrene derivatives and other vinyl monomers, such as styrene, vinyl ether, acrylonitrile, vinyl chloride, acrylic esters, maleic anhydride or vinyl esters of various organic acids; Iodine, chlorine, bromine, etc. of at least one polymer selected from the above-mentioned hydroxystyrene and hydroxystyrene derivatives and a copolymer of at least one selected from hydroxystyrene and hydroxystyrene derivatives with other vinyl monomers. Examples include halogenated hydroxystyrene copolymers, which are halides.

Among these hydroxystyrene resins, hydroxystyrene copolymers, α-methyl-p-hydroxystyrene polymers, and α-methyl-m-hydroxystyrene polymers are particularly preferred.

Note that the hydroxystyrene resin is manufactured by solution radical polymerization or the like.

Further, the molecular weight of the hydroxystyrene resin is not particularly limited, but the weight average molecular weight in terms of polystyrene is
Usually 200~200,000゜preferably 500~t
oo, 000, particularly preferably from 600 to 50,000.

In the present invention, 1°2-quinonediazide sulfonyl halide may be condensed with the alkali-soluble resin.

Examples of the 1,2-quinonediazide sulfonyl halide include 1,2-ki,nondiazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-5-sulfonyl chloride, and 1,2-naphthoquinonediazide-6-
Sulfonyl chloride, 1,2-naphthoquinone diazide
1,2-naphthoquinonediazide sulfonyl halides such as 4-sulfonylbromide, 1,2-naphthoquinonediazide-5-sulfonylbromide, 1,2-naphthoquinonediazide-6-sulfonylbromide; and 1,2-benzoquinonediazide- 4-sulfonyl chloride, 1.2
-benzoquinonediazide-5-sulfonyl chloride, 1
．． 2-pendaquinonediazide-6-sulfonyl chloride, 1°2-benzoquinonediazide-4-sulfonylbromide, 1,2-benzoquinonediazide-5-sulfonylbromide, 1,2-benzoquinonediazide-6-sulfonylbromide, etc. Mention may be made of 1,2-benzoquinonediazide sulfonyl halide, with 1,2-naphthoquinonediazide-4sulfonyl chloride being particularly preferred.

In the radiation-sensitive resin composition used in the present invention, if the alkali-soluble resin is not imparted with radiation sensitivity, a 1,2-quinonediazide compound is usually contained.

This 1,2-quinonediazide compound comprises a (poly)hydroxy compound and the 1,2-quinonediazide sulfonylvalide, preferably 1,2-penzoquinonediazide-
It is obtained by condensing 4-sulfonyl chloride, 1,2-naphthoquinonediazide-4-sulfonyl chloride, ], 2-naphthoquinonediazide-5-sulfonyl chloride, etc. in the presence of a basic catalyst.

Examples of basic catalysts that can be used include amines such as trimethylamine, triethylamine, tripropylamine, pyridine, and tetramethylammonium hydroxide, and inorganic alkalis such as sodium hydroxide, potassium hydroxide, and sodium carbonate. The amount of the basic catalyst used is generally 0.8 to 2 mol, preferably 1 to 1.5 mol, per mol of 1,2-quinonediazide sulfonic acid halide used.

The condensation reaction is usually carried out in the presence of a solvent.

Examples of the solvent include water, dioxane, diethyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, γ-butyrolactone, N-methylpyrrolidone,
Examples include N,N-dimethylacetamide, N,N-dimethylformamide, ethylene carbonate, propylene carbonate, and the like. The amount of the solvent used is usually 100 to 1000 parts by weight per 100 parts by weight of the reaction raw materials. The temperature of the condensation reaction varies depending on the solvent used, but is usually -20 to
60°C, preferably 0 to 40''C.

Purification methods after the condensation reaction include filtering the hydrochloride produced as a by-product, or adding water to dissolve the hydrochloride, purifying it by reprecipitation with a large amount of acidic water such as a dilute aqueous hydrochloric acid solution, and then drying. An example of how to do this can be given.

As this 1,2-quinonediazide compound, for example, p
- Cresol, resorcinol, pyrogallol, etc.
1゜2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester of polyhydroxybenzene; 2,4-
Dihydroxyphenyl-n-hexyl ketone, 2.4=
Dihydroxybenzophenone, 2,3.4-)lihydroxyphenyl-n-hexyl ketone, 23.4-1-lyhydroxybenzophenone, 2,4゜6-dolihydroxybenzophenone, 2.2'4.41 -tetrahydroxybenzophenone, 2゜3.4.4'-tetrahydroxybenzophenone, 2.3,4.4'-tetrahydroxy-3'-methoxybenzophenone, 2.2', 3.4
-tetrahydroxy-4'-methylbenzophenone, 2
゜3.4.2', 4'-pentahydroxybenzophenone, 2,3,4.2', 5'-pentahydroxybenzophenone-1,2-naphthoquinonediazide-5-sulfonic acid ester, 2,3,4. 2'6'-pentahydroxybenzophenone, 2,3°4.3', 4'-pentahydroxybenzophenone, 2,3,4.3', 5'-pentahydroxybenzophenone, 2,3,4.2', 3
',4'-hexahydroxybenzophenone, 2,3.
4゜3'4'5'-hexahydroxybenzophenone,2.3,4.2',4',6'-hexahydroxybenzophenone,2,4,6.2',4'-pentahydroxybenzophenone, 2,4,6°2951-pentahydroxybenzophenone, 2.4,6.2',6
'-Pentahydroxybenzophenone, 2,4,6.3
',4'-pentahydroxybenzophenone, 2,4,
6.3", 5'-pentahydroxybenzophenone, 2
,4,6゜3'4'5'-hexahydroxybenzophenone,2,4,6.2',4',6'-hexahydroxybenzophenone,2,3,4,5.2'pentahydroxybenzo Phenone, 2,3,4°5.3'-
Pentahydroxybenzophenone, 2°3.4,5.4
'-Pentahydroxybenzophenone, 2,3,4,5
．． 2', 4'-hexahydroxybenzophenone, 2,
3,4,5.2'5'-hexahydroxybenzophenone, 2,3°4; 5,2°,6'-hexahydroxybenzophenone, 2,3,4,5.3',4'-hexa Hydroxybenzophenone, 2,3,4.5,3゜5
°-hexahydroxybenzophenone, 2,3°4.5
．． 2',3',4'-heptahydroxybenzophenone, 2,3,4,5.3',4°,5'-heptahydroxybenzophenone, 2,3,4°5.2',4',6 '
-hebutahydroxybenzophenone, 2,3,4.2"
, 4'-pentahydroxy-5-methylbenzophenone, 2.3.4°2', 4'-pentahydroxy-5-ethylbenzophenone, 2,3,4.2', 4'-punkhydroxy-5-n -Propylbenzophenone, 2゜3
．． 4.2', 4'-pentahydroxy-5-n-butylbenzophenone, 2,3,4.2', 5'-pentahydroxy-5-methylbenzophenone, 2.3,4.2'
, 5'-pentahydroxy-5-n-propylbenzophenone, 2,3,4.2'6'-pentahydroxy-5
-Methylbenzophenone, 2,3,4.2',6'-pentahydroxy-5-n-propylbenzophenone, 2
,3°4.3',4'-pentahydroxy-5-methylbenzophenone,2,3,4.3',4'-pentahydroxy-5-n-propylbenzophenone,2.3,4
．． 3',5'-pentahydroxy-5-methylbenzophenone, 2,3,4.3',5'pentahydroxy-5
-n-propylbenzophenone, 2,3,4.2',3
'4''-hexahydroxy-5-methylbenzophenone, 2,3°4.2',3',4'-hexahydroxy-5=n-propylbenzophenone, 2,3,4.3
'4' 51-hexahydroxy-5-methylbenzophenone, 2.3,4.3',4'',5'-hexahydroxy-5-n-propylbenzophenone, 2,3,4.
2', ', 6'-hexahydroxy-0xy-5-methylbenzophenone, 2,3,4゜2'4',6'-hexahydroxy-5-n-propylbenzophenone, 2
,3.2',3'4'-pentahydroxy-4-methoxybenzophenone,2,3.2',3'4'-bentahydroxy-4-ethoxybenzophenone-2,3°2',3',4'-Pentahydroxy-4-n-propoxybenzophenone,2,3.2',3'4'-Pentahydroxy-4-n-butoxybenzophenone, 2,3
．． 3', 4', 5'-pentahydroxy-4-methoxybenzophenone, 2°3.3', 4°, 5"-pentahydroxy-4-n-propoxybenzophenone, 2.3
．． 2'4'6'-pentahydroxy-4-methoxybenzophenone,2,3.2',4',6'-pentahydroxy-4-n-propoxybenzophenone, 2.3,
4.2',4'-pentahydroxy-5-chlorobenzophenone, 2,3,4.2'4'-pentahydroxy-
5-bromobenzophenone, 2,3,4.2',6'-
Pentahydroxy-5-chlorobenzophenone, 2.3
, 4.2'61-pentahydroxy-5-bromobenzophenone, 2,3.4.3', 4", 5°-hexahydroxy-5-chlorobenzophenone, 2.3°4.3'
, 4',5'-hexahydroxy-5bromobenzophenone, 2,3,4.2',4'-pentahydroxy-5
-cyanobenzophenone, 2.3, 4.3', 4'
5'-hexahydroxy-5-cyanobenzophenone,
2,3,4.2'4''-pentahydroxy-5-nitrobenzophenone, 2,3.4.3'4"5'-hexahydroxy-5-nitropentuphenone,2,4゜3',4',5'-pentahydroxy-5-acetylbenzophenone,2,4.3',4',5'-pentahydroxy-5-benzoylben7''phenone, 2,3,4
．． 3',4',5'-hexahydroxy-5-acetylbenzophenone, 2,3゜4.3',4',5'-hexahydroxy-5-benzoylbenzophenone, 2,4
．． 3', 4'5'-pentahydroxy-5-benzylbenzophenone, 2,3,4.3'4',5'-hexahydroxy-5-benzylbenzophenone, 2°3.
4.2',4'-pentahydroxybenzophenone, 2
,3,4.2'6'-pentahydroxybenzophenone,2,3,4,3°,4'5'-hexahydroxybenzophenone,2,4°6.2',6'-pentahydroxybenzophenone, 2 ,4,6.3',4',5'
-hexahydroxybenzophenone, 2,3,4.5.
4'pentahydroxybenzophenone, 2,3,4゜5
．． 2°26'-hexahydroxybenzophenone, 2,
3,4,5.3',4',5'-hebutahydroxybenzophenone, 2,3,4.2'4'-pentahydroxy-5-methylbenzophenone, 2.3,4,2°,6'
-pentahydroxy-5-methylbenzophenone, 2.
3,4.3'4' 51-hexahydroxy-5-methylbenzophenone, 2,3.3',4',5'-pentahydroxy-4-methoxybenzophenone, 2°3.4
．． 3', 4'5'-hexahydroxy-5-chlorobenzophenone,2,3.4.3'4'5'-hexahydroxy-5-acetylbenzophenone, 2,3,
4.3',4',5''hexahydroxy-5-benzoylbenzophenone, 2.3,4.2',6'-pentahydroxybenzophenone, 2,3,4.3',4',5
'-hexahydroxybenzophenone, 2,4.6°3
'4'5"-Hexahydroxybenzophenone,2,3,4.3'4'5'-Hexahydroxy-5-methylbenzophenone1.2,3°3',4'
, 5'-pentahydroxy-4-methoxybenzophenone, 2,3,4.3',4'.

1. of (poly)hydroxyphenylalkyl ketones or (poly)hydroxyphenylaryl ketones such as 5'-hexahydroxy-5-benzoylbenzophenone.
2-benzoquinonediazide-4-sulfonic acid ester,
1.2-naphthoquinonediazide-4-sulfonic acid ester and l,2-naphthoquinonediazide-5-sulfonic acid ester: bis(P-hydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)methane, bis(2,3 ,4-trihydroxyphenyl)methane, 2,
2-bis(p-hydroxyphenyl)propane, 2,2
-bis(2,4-dihydroxyphenyl)propane, 2
, 1.2-benzoquinonediazide-4-sulfonic acid ester of bis[(poly)hydroxy(2enyl)alkane such as 2-bis(2,3,4-trihydroxyphenyl)propane, 1.2-naphthoquinonediazide-4 -Sulfonic acid ester and 1,2-naphthoquinone diazide-
5-sulfonic acid ester; lauryl 3,5-dihydroxybenzoate, phenyl 2,3.4-)rihydroxybenzoate, propyl 3,4.5-1-IJ hydroxybenzoate, 3,4.5-trihydroxy 1 of (poly)hydroxybenzoic acid alkyl esters such as phenyl benzoate or (poly)human ot-cybenzoic H aryl esters
, 2-benzoquinonediazide-4-sulfonic acid ester, 1゜2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester; bis(2,5-dihydroxybenzoyl)methane, bis (2,3,4-trihydroxybenzoyl)methane, bis(2,4゜6-trihydroxybenzoyl)methane, p-bis(2,5-dihydroxybenzoyl)benzene, p-bis(2,3,4- 1-dihydroxybenzoyl)benzene, p-bis(2,4,6-)
Bis[(poly)hydroxybenzoyl coalkane such as dihydroxybenzoyl)benzene or 1°2-benzoquinonediazide-4-sulfonic acid ester of bis[(poly)hydroxybenzoyl]benzene, 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1.
2-naphthoquinonediazide-5-sulfonic acid ester;
Ethylene glycol rouge (3,5-dihydroxybenzoate), polyethylene glycol rouge (3,4,5-
1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-benzoquinonediazide-4-sulfonic acid ester of (poly)ethylene glycol di[(poly)hydroxybenzoate] such as ) dihydroxybenzoate) Naphthoquinone diazide-5-sulfonic acid ester is mentioned. Besides these compounds,
“Light-3 ensive” by J. Kosar
5yst ems''339-352. (1965),
J.

hn Wtle & 5ons (New Y
.

rk) and W.S. De Forest” Ph.
.

50. (1975),
McGraw-Hllll, Inc. (New
It is also possible to use 1,2-nondiazi l' compounds published in J. York).

The 1,2-quinonediazide compound is preferably blended in an amount of 5 to 100 parts by weight, more preferably 10 to 50 parts by weight, per 100 parts by weight of the alkali-soluble resin. If the amount is less than 5 parts by weight, the amount of carboxylic acid produced by the 1゜2-quinonediazide compound absorbing radiation is small, making patterning difficult. If it exceeds 100 parts by weight, short-term radiation irradiation will , 2-quinonediazide compound may be insufficiently decomposed and development may become difficult.

A sensitizer can be added to the radiation-sensitive resin composition used in the present invention in order to improve the degree of anger. As a sensitizer, for example, 2H-pyrido[3°2-b)-1,4-
Oxazin-3(4H)ones, 10H-pyrido(3,
2-b) (1,4)-Benzothiazines, urazoles, hydantoins, barbylic acids, glycine anhydrides, l-hydroxybenzotriazoles, alloxanes, maleimides, etc. can be mentioned. The amount of the sensitizer to be blended is usually 100 parts by weight or less per 100 parts by weight of the 1,2-quinonediazide compound.

Furthermore, a surfactant may be added to the radiation-sensitive resin composition used in the present invention in order to improve coating properties, such as striations and developability of the radiation-exposed area after dry coating film formation. Examples of surfactants include nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, polyethylene glycol dilaurate, and polyethylene glycol distearate. Surfactant: FTOP EF301. EF303, EF352 (manufactured by Shin-Akita Kasei Co., Ltd.), Megafix F171, F172, Fi73 (manufactured by Dainippon Ink Co., Ltd.), Florado FC430, FC431
(manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, 5CIOI, 5C102, 5CI
Fluorine-based surfactants such as 03.5C104, 5C105, and 5C106 (manufactured by Asahi Glass Co., Ltd.); organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.) and acrylic acid-based or methacrylic acid-based (co)polymer Polyflow Nα75
, Nα95 (manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), etc. are used. The blending amount of the surfactant is usually 2 parts by weight or less per 100 parts by weight of the radiation-sensitive resin used in the present invention.

In addition, the radiation-sensitive resin composition used in the present invention contains a coloring agent to visualize the latent image of the radiation-exposed area and to reduce the effect of halation during radiation irradiation, and to improve adhesiveness. An adhesion aid, and if necessary, a storage stabilizer, an antifoaming agent, etc. can also be added.

The radiation-sensitive resin composition used in the present invention is prepared by dissolving a predetermined amount of the alkali-soluble resin and various compounding agents in a solvent, and filtering the solution through a filter with a pore size of about 0.1 μm, for example.

Examples of the solvent used in this case include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether,
Ethylene glycol alkyl ethers such as ethylene glycol monobutyl ether; diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether 1. Diethylene glycol dialkyl ethers such as diethylene glycol dibutyl ether; ethylene glycol alkyl acetates such as methyl cellosolve acetate and ethyl cellosolve acetate; propylene glycol alkyl ether acetate such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol propyl ether acetate Aromatic hydrocarbons such as toluene and xylene; Ketones such as methyl ethyl ketone and cyclohexanone; methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, 2-
Ethyl hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl oxyacetate, 2-hydroxy-3-
Methyl methylbutanoate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-
3-Methoxybutylbutin-l-1 Esters such as ethyl acetate, butyl acetate, methyl acetoacetate, and ethyl acetoacetate; amides such as dimethylformamide and dimethylacetamide can be used. These solvents can be used alone or in combination of two or more. Additionally, benzyl ethyl ether, dihexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octatool, 1-nonanol, hensyl alcohol, benzyl acetate, ethyl benzoate, oxalic acid. High boiling point solvents such as diethyl, diethyl maleate, γ-butyrolactone, ethylene carbonate, propyl carbonate, phenyl cellosolve acetate can be added.

Examples of the developer for the resist layer formed from the radiation-sensitive resin composition include inorganic alkali compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; ethylamine, n- Primary amines such as propylamine;
Secondary amines such as diethylamine and di-n-propylamine; Tertiary amines such as triethylamine and methyldiethylamine; Alcohol amines such as dimethylethanolamine and triethanolamine; Tetramethylammonium hydroxide and tetraethylammonium hydroxy ammonium hydroxides such as trimethyl-hydroxyethylammonium hydroxide; pyrrole, piperidine, 1,8-diazabicyclo(
Usually, an alkaline aqueous solution containing 1 to 10% by weight of cyclic amines such as 5,4゜0)-7-undecene and 1,5-diazabicyclo(4,3,0)-5-nonane is used. be done.

Further, the developer may contain a water-soluble organic solvent, such as methanol,
Appropriate amounts of alcohols such as ethanol and surfactants may also be added.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to Examples.

Example 1 A mixture of m-cresol and 3,5-xylenol (m-
Cresol: 3,5-xylenol = 1:4, molar ratio)
Novolac resin 20 having a polystyrene equivalent weight average molecular weight of 11,000, which is a condensation of formaldehyde and
After dissolving 6 g, 2.3,4° 4'-tetrahydroxybenzophenone-1,2-naphthoquinonediazide-5-sulfonic acid ester (condensation ratio 2.5) and 60 g of ethyl cellosolve acetate with thorough stirring at room temperature, Pore diameter 0.
A radiation-sensitive resin solution was prepared by filtration through a 1 μm membrane filter. After applying this solution on a silicon wafer using a spinner, pre-baking it at 90°C for 2 minutes.
．． A resist layer with a thickness of 2 μm was formed. Next, the stepper was exposed to light using a Kon Co., Ltd. N5R1505G4D), and exposed to a 50 ppm aqueous solution of benzalkonium chloride at 25°C for 30 minutes.
Immersed for 0 seconds. Thereafter, the resist pattern was developed with a 2.38% by weight aqueous tetramethylammonium hydroxide solution at 25° C. for 60 seconds and rinsed with water to form a resist pattern.

The exposure time that resulted in a residual film ratio of O (hereinafter referred to as 'EthJ), and the exposure time that accurately formed a 0.8 μm line and space resist pattern (hereinafter referred to as 'EthJ')
opJ), exposure margin (E, h/E, , ), resolution, contrast (the slope of the sensitivity residual film characteristic curve that shows the relationship between film residual rate and exposure amount), and overall angle (
The angle between the 0.8 μm line and space pattern and the substrate was measured. The results are shown in Table 1.

Example 2 In Example 1, a mixture of m-cresol and 2.3.5-trimethylphenol (
m-cresol: 2,3.5-trimethylphenol =
5=4, molar ratio) and formaldehyde, and a 1.2-quinonediazide compound. 3. 4. 4'-Tetrahydroxybenzophenone-1,2-naphthoquinonediazide-5-
A solution of a radiation-sensitive resin was prepared in the same manner as in Example 1, except that 6 g of sulfonic acid ester (condensation ratio: 2.75) was used. This solution was applied onto a silicon wafer using a spinner, then exposed using a stepper, and then prebaked at 90°C for 60 seconds. Thereafter, it was immersed in 0.5 ppm water of benzalkonium chloride at 25°C for 30 seconds, developed and rinsed in the same manner as in Example 1, and then
The resist pattern was evaluated and the results are shown in Table 1.

Comparative Example 1 A resist pattern was formed in the same manner as in Example 1, except that it was developed and rinsed without being treated with a benzalkonium chloride aqueous solution, and evaluated.
The results are shown in Table 1.

Comparative Example 2 A resist pattern was formed in the same manner as in Example 2, except that the treatment with the benzalkonium chloride aqueous solution was not performed and the resist pattern was rinsed, and the resist pattern was evaluated.
The results are shown in Table 1.

Margins below [Effects of the Invention] According to the resist pattern forming method of the present invention, a resist pattern with high resolution, high contrast, and an excellent pattern profile can be obtained. Therefore, the method of the present invention is a resist pattern forming method for fabricating integrated circuits sensitive to radiation such as ultraviolet rays, deep ultraviolet rays, This is suitable as a method for forming a positive resist pattern.

Claims (1)

[Claims] (1) A resist layer is formed on a substrate using a radiation-sensitive resin composition containing an alkali-soluble resin, the resist layer is irradiated with radiation, and then developed to form a resist pattern. 1. A method for forming a resist pattern, which comprises bringing a resist layer into contact with an aqueous solution of a quaternary ammonium salt before developing the resist layer.