JP2002006501A - Chemical amplification resist composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist composition, superior in transmittance to a light of <=170 nm wavelength and suitable particularly for use in F2 excimer laser lithography. SOLUTION: The chemical amplification resist composition contains a resin binder and a radiation-sensitive compound. The resin binder is alkali-soluble or is made alkali-soluble by chemical changes caused by the action of the radiation sensitive compound after irradiation and has a polymerization unit, derived from a monomer of formula (I) (where Q is H, methyl or a 1-4C fluoroalkyl; R1 is a 1-14C alkyl which may be substituted by halogen, hydroxyl or an alicyclic ring, or an alicyclic or lactone ring which in turn may be substituted by halogen, hydroxyl or alkyl; and at least one of Q and R1 has at least one fluorine atom).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a chemically amplified resist composition used for fine processing of semiconductors.

[0002]

2. Description of the Related Art A lithography process using a resist composition is usually employed for fine processing of a semiconductor.
In lithography, as represented by the Rayleigh diffraction limit equation, in principle, the shorter the exposure wavelength, the higher the resolution can be increased. The exposure light source for lithography used in the manufacture of semiconductors has a wavelength of 436 nm.
Line, wavelength 365nm of i-line, KrF excimer laser having a wavelength of 248 nm, have become ArF excimer laser and yearly short wavelength of 193 nm, is further F ₂ excimer laser promising wavelengths 157nm as a next generation exposure light source I have. For KrF excimer laser exposure and ArF excimer laser exposure, a so-called chemically amplified resist utilizing the catalytic action of an acid generated by exposure is widely used because of its excellent sensitivity. Also, there is a high possibility that a chemically amplified resist is used for F ₂ excimer laser exposure in terms of sensitivity.

As a resist for KrF excimer laser exposure, a polyvinylphenol-based resin has been used. On the other hand, the resin used for the resist for ArF excimer laser exposure does not have an aromatic ring in order to secure the transmittance of the resist, and has an alicyclic ring instead of the aromatic ring in order to have dry etching resistance. Things are known to be good. As such alicyclic resin,
DC Hofer, Journal of Photopolymer Science and Te
Various types are known as described in Chnology, Vol. 9, No. 3, 387-398 (1996). Also, S. Takechi e
t al, Journal of Photopolymer Science and Technolog
y, Vol. 9, No. 3, 475-487 (1996) and JP-A-9-73173, a polymer or copolymer of 2-methyl-2-adamantyl methacrylate is used as a resin for a chemically amplified resist. When used, 2-methyl-2-adamantyl is cleaved by the action of an acid to act positively, and provides high dry etching resistance, high resolution, and good adhesion to a substrate. It has been reported.

However, resins used in conventional resist KrF excimer laser exposure or ArF excimer laser exposure, 170 nm or less wavelengths of light, for example, with respect to F ₂ excimer laser with a wavelength of 157 nm, a sufficient permeation No rate was shown. When the transmittance is low, various properties such as profile, contrast, and sensitivity are adversely affected.

[0005]

OBJECTS OF THE INVENTION It is an object of The present invention is excellent in transmittance of light with a wavelength below 170 nm, in particular to provide a resist composition suitable for F ₂ excimer laser lithography. The present inventors, by using a resin having a polymerization unit derived from a specific monomer as a resin constituting the resist composition, 157nm
It has been found that the transmittance at the wavelength of the F ₂ excimer laser can be improved, and the present invention has been completed.

[0006]

That is, the present invention comprises a binder resin and a radiation-sensitive compound, wherein the binder resin is itself alkali-soluble or undergoes a chemical change by the action of the radiation-sensitive compound after irradiation. And alkali-soluble, represented by the following formula (I)

[0007]

(Wherein Q is hydrogen, methyl or C 1 -C 1)
And R ¹ represents a fluoroalkyl having 4 to 1 carbon atoms which may be substituted with a halogen, a hydroxyl group or an alicyclic ring.
4 represents an alicyclic ring or a lactone ring which may be substituted with an alkyl or halogen, a hydroxyl group or an alkyl group, and at least ^one of Q and R ¹ is at least 1
Has fluorine atoms. The present invention provides a chemically amplified resist composition having a polymerized unit derived from the monomer represented by the formula (1).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, as shown in the above formula (I), at least ^one of Q and R ¹ is derived from a (meth) acrylate having at least one fluorine atom. A resin having units is used. Here, Q represents hydrogen, methyl or fluoroalkyl having 1 to 4 carbon atoms. When the fluoroalkyl has 3 or more carbon atoms, it may be linear or branched. The fluoroalkyl may have at least one fluorine atom, but preferably has two or more fluorine atoms. A trifluoromethyl group is practical because it is easily available.

R ¹ is alkyl having 1 to 14 carbon atoms which may be substituted with a halogen, a hydroxyl group or an alicyclic ring, or an alicyclic ring which may be substituted with a halogen, a hydroxyl group or an alkyl group. Represents a lactone ring. The alkyl having 1 to 14 carbon atoms which may be substituted with a halogen, a hydroxyl group or an alicyclic ring may be linear or branched when having 3 or more carbon atoms. Here, examples of the halogen include fluorine, chlorine, and bromine. Examples of the alicyclic ring include a cyclopentyl ring, a cyclohexyl ring, a bicyclo [2.2.1] heptyl ring, and a bicyclo [4.3.
0] nonyl ring, bicyclo [4.4.0] decanyl ring, tricyclo [5.2.1.0 ^2,6 ] decanyl ring, adamantyl ring and the like. Among them, C1 to C1 which may have at least one fluorine-substituted hydroxyl group.
Four fluoroalkyls are preferred. Halogen, hydroxyl,
The alkyl group in the alicyclic ring or lactone ring which may be substituted with an alkyl group is generally a lower alkyl group having about 1 to 4 carbon atoms. When it has 3 or more carbon atoms, it may be linear or branched. Examples of the halogen include the same as those described above, and examples of the alicyclic ring include the same alicyclic ring as described above. Examples of the lactone ring include a 2-oxooxetane-3-yl ring, a 2-oxooxolan-3-yl ring, a 2-oxooxan-3-yl ring, and a 2-oxepanone-3-yl ring.

When R ¹ has at least one fluorine atom, considering the availability of monomer (I) from the market, R ¹ is represented by the following formula (II)

[0012] (In the formula, R ² represents hydrogen, alkyl or fluoroalkyl, R ³ represents fluoroalkyl, and the total carbon number of R ² and R ³ is 1 to 11. n represents 0 or 1.)
It is preferred that The alkyl and fluoroalkyl herein may be linear or branched when the number of carbon atoms is 3 or more. The fluoroalkyl may have at least one fluorine atom, but preferably has two or more fluorine atoms. Of course, it may be perfluoroalkyl. Further, when the hydroxyl group is substituted, hydrophilicity is increased, so that adaptation to a developer can be improved.

Specific examples of the fluoroalkyl (meth) acrylate represented by the formula (I) include the following compounds.

2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate, 1-trifluoromethyl-2,2,2-trifluoroethyl acrylate, 1-trimethyl methacrylate Fluoromethyl-
2,2,2-trifluoroethyl, methacrylic acid 2,
2,3,3-tetrafluoropropyl, 2,2,3,4,4,4-hexafluorobutyl methacrylate, 1H, 1H, 11H-acrylic acid, eicosafluoroundecyl, 1H, 1H, 11H-methacrylic acid Eicosafluoroundecyl,

3- (perfluoro-3-methylbutyl) -2-hydroxypropyl methacrylate, methacrylic acid
3- (perfluoro-5-methylhexyl) -2-hydroxypropyl, methacrylic acid 3- (perfluoro-7-
Methyloctyl) -2-hydroxypropyl, 3- (perfluorobutyl) -2-hydroxypropyl methacrylate, 3- (perfluorohexyl) -2 methacrylate
-Hydroxypropyl, methacrylic acid 3- (perfluorooctyl) -2-hydroxypropyl, methacrylic acid
3- (perfluoro-3-methylbutyl) -2-hydroxypropyl, acrylate 3- (perfluoro-5-methylhexyl) -2-hydroxypropyl, acrylate 3
-(Perfluoro-7-methyloctyl) -2-hydroxypropyl, 3- (perfluorobutyl) acrylate
2-hydroxypropyl, 3- (perfluorohexyl) acrylate-2-hydroxypropyl, acrylate 3
-(Perfluorooctyl) -2-hydroxypropyl,

[0016] Such.

By the polymerization of the monomer represented by the formula (I), a unit represented by the following formula (Ia) is formed.

[0018]

Wherein Q and R ¹ are as defined above.

The binder resin used in the present invention comprises:
It is alkali-soluble by itself, or becomes alkali-soluble by a chemical change caused by the action of a radiation-sensitive compound described below after irradiation. Such a property of being alkali-soluble by itself or of being chemically soluble by the action of a radiation-sensitive compound after irradiation and becoming alkali-soluble is generally required for alkali-developed chemically amplified resists. Therefore, such a property can be imparted by applying a conventionally known technique to a chemically amplified resist.

The binder resin itself is alkali-soluble, or becomes alkali-soluble by the action of a radiation-sensitive compound after irradiation, and the irradiated portion of the resist film containing the binder resin is removed by alkali development. In this case, a positive resist is used. That is, the chemically amplified positive resist is such that an acid or a base generated from a radiation-sensitive compound in a radiation-irradiated portion is diffused by a subsequent heat treatment (post exposure bake) to cleave a protective group such as a resin and to remove an acid or a base. Is regenerated, so that the irradiated portion is alkali-solubilized. In a chemically amplified positive resist, a binder resin is alkali-soluble, and in addition to the binder resin and the radiation-sensitive compound, has a protective group that can be cleaved by the action of an acid or a base. A resin containing a dissolution inhibitor which becomes alkali-soluble after the above protective group is cleaved by the action of an acid or a base, and the binder resin is cleaved by the action of an acid or a base. Some protective groups have a protecting group which is insoluble or hardly soluble in alkali, but become alkali-soluble after the protective group is cleaved by the action of an acid or a base.

On the other hand, when the binder resin is alkali-soluble and the radiation-irradiated portion of the resist film containing the binder resin is cured, and the portion not irradiated with the radiation is removed by alkali development, a negative resist is obtained. . That is, a chemically amplified negative resist usually contains a binder resin which is alkali-soluble and contains a crosslinking agent in addition to the binder resin and the radiation-sensitive component, and an acid or a base generated from the radiation-sensitive compound in the radiation-irradiated portion is not used. It is diffused by a subsequent heat treatment (post exposure bake), acts on a crosslinking agent, and cures the binder resin in the radiation-irradiated portion to make it alkali-insoluble.

The alkali-soluble site in the binder resin used in the present invention is, for example, a unit having a phenol skeleton or a unit having a (meth) acrylate ester skeleton and having an alicyclic ring and a carboxyl group on the alcohol side of the ester. And units of unsaturated carboxylic acids. Specifically, a vinyl phenol unit, an isopropenyl phenol unit, an alicyclic ester of (meth) acrylic acid, a unit having a carboxyl group in the alicyclic ring,
And (meth) acrylic acid units. The presence of a relatively large number of such alkali-soluble units makes the resin itself alkali-soluble. of course,
Alkali-insoluble units may be present together with these units, for example, a resin having a mixed unit in which a part of the hydroxyl group of a vinylphenol unit or an isopropenylphenol unit is alkyletherified, vinylphenol or isopropenylphenol Having a mixed unit obtained by copolymerization with a polymerizable unsaturated compound and a resin having a mixed unit obtained by copolymerization of an alicyclic ester of (meth) acrylic acid and (meth) acrylic acid, etc. Also, if the resin is alkali-soluble as a whole, it can be a resin which is itself alkali-soluble as defined in the present invention.

On the other hand, when a resin which is itself insoluble or hardly soluble in alkali but becomes alkali-soluble by the action of a radiation-sensitive compound after irradiation is used as a binder, a site having such properties is, for example, An alkali-soluble unit such as a unit having a phenol skeleton or a unit having a carboxyl group exemplified above is introduced with a protecting group which has a dissolution inhibiting ability in an alkali developing solution but can be cleaved by the action of an acid or a base. May have been done. The group which has the ability to inhibit dissolution in an alkali developer but is unstable to an acid or a base can be any of various known protecting groups.

A group which has an ability to inhibit dissolution in an alkali developing solution but is unstable to an acid includes, for example, tert-
Groups in which a quaternary carbon is bonded to an oxygen atom, such as butyl, tert-butoxycarbonyl and tert-butoxycarbonylmethyl; tetrahydro-2-pyranyl, tetrahydro-2
-Furyl, 1-ethoxyethyl, 1- (2-methylpropoxy) ethyl, 1- (2-methoxyethoxy) ethyl, 1- (2-acetoxyethoxy) ethyl, 1- [2
-(1-adamantyloxy) ethoxy] ethyl and 1
Acetal-type groups such as-[2- (1-adamantanecarbonyloxy) ethoxy] ethyl; 3-oxocyclohexyl, 4-methyltetrahydro-2-pyrone-4
-Yl (derived from mevalonic lactone) and 2-
Examples thereof include a residue of a non-aromatic cyclic compound such as alkyl-2-adamantyl, and these groups are substituted with hydrogen of a phenolic hydroxyl group or hydrogen of a carboxyl group. These protective groups are obtained by subjecting an alkali-soluble resin having a phenolic hydroxyl group or a carboxyl group to a known protective group introduction reaction, or performing copolymerization using an unsaturated compound having such a group as one monomer. Thereby, it can be introduced into the resin.

On the other hand, examples of groups unstable to a base include alkyl carbamate and cycloalkyl carbamate-based groups. Specifically, for example, a resin having a phenol skeleton and having a unit in which a part of the phenolic hydroxyl group is replaced with an alkylcarbamoyloxy group or a cycloalkylcarbamoyloxy group can be a binder resin of this type.

In the present invention, a polymer unit having an alkali-soluble group in the monomer represented by the above formula (I) or a group which undergoes a chemical change by the action of a radiation-sensitive compound after irradiation to form an alkali-soluble group in the binder resin. In the case other than the above, in addition to the polymerized unit derived from the monomer represented by the formula (I), a polymerized unit having an alkali-soluble group as described above or a chemical change caused by the action of the radiation-sensitive compound after irradiation is performed. Thus, a polymerized unit having a group which becomes alkali-soluble is present. In this case, the resin has a monomer represented by the formula (I) as one monomer and has an alkali-soluble group, or has a group which undergoes a chemical change by the action of a radiation-sensitive compound after irradiation to become alkali-soluble. It is produced by performing copolymerization using a polymerizable unsaturated compound as another monomer. The copolymerization itself can be carried out according to a conventional method, for example, by dissolving each monomer in an appropriate solvent, starting polymerization in the presence of a polymerization initiator, and proceeding the reaction. Further, for example, when a hydroxyl group in a unit of vinylphenol or isopropenylphenol is modified with an alkyl or a group capable of leaving by the action of a radiation-sensitive compound after irradiation, the monomer represented by the formula (I) may be modified with vinylphenol or isopropenyl. After copolymerization with phenol, the hydroxyl group of the vinylphenol unit or isopropenylphenol unit is generally modified.

By incorporating polymerized units derived from the monomer of formula (I) into a binder resin, the resin can be converted to light having a wavelength of 170 nm or less, for example, F light having a wavelength of 157 nm.
And it is excellent in transmittance for _excimer laser. Therefore, the polymerized unit derived from the monomer of the formula (I) is present in such a range that such a performance can be achieved and the resin itself is alkali-soluble or is alkali-soluble by the action of the radiation-sensitive compound after irradiation. It should be done. Although depending on the type and type of the resist, generally, the ratio of the polymerization unit derived from the monomer of the formula (I) may be appropriately selected from the range of about 10 to 100 mol% of the whole resin.

The presence of a relatively large number of alkali-soluble units makes the resin itself alkali-soluble. A binder resin that is itself alkali-soluble can be used as a positive resist in combination with a dissolution inhibitor and a radiation-sensitive compound, and can be a negative resist in combination with a crosslinking agent and a radiation-sensitive compound. .

The dissolution inhibitor used when the alkali-soluble resin itself is used as a binder to form a positive resist has the ability to inhibit the phenolic hydroxyl group of a phenolic compound from dissolving in an alkali developing solution. It may be a compound protected by a group that is cleaved by the action of a base.
Examples of the group that is cleaved by the action of an acid include a tert-butoxycarbonyl group, which is substituted with hydrogen of a phenolic hydroxyl group. Dissolution inhibitors having a group that is cleaved by the action of an acid include, for example, 2,2-bis (4-tert-butoxycarbonyloxyphenyl) propane, bis (4-tert-butoxycarbonyloxyphenyl) sulfone, 5-bis (4-tert-butoxycarbonyloxyphenyl) -1,1,3-trimethylindane and the like are included. On the other hand, as a group that is cleaved by the action of a base, for example, an alkyl carbamate or a cycloalkyl carbamate-based group is exemplified, and a compound in which a phenolic hydroxyl group is replaced with an alkylcarbamoyloxy group or a cycloalkylcarbamoyloxy group is It can be a dissolution inhibitor having a group that is cleaved by action. When such a dissolution inhibitor is used, it is convenient to include it in the binder component together with the binder resin.

The crosslinking agent used when the alkali-soluble resin itself is used as a binder and a negative resist is used,
Any material can be used as long as the binder resin is crosslinked by the action of an acid or a base. In general, the crosslinking agent often causes a crosslinking reaction by the action of an acid. Usually, a compound having a methylol group or an alkyl ether thereof is used. Specific examples include hexamethylolmelamine,
Pentamethylolmelamine, tetramethylolmelamine, hexamethoxymethylmelamine, methylolated melamine such as pentamethoxymethylmelamine and tetramethoxymethylmelamine or an alkyl ether thereof,
Methylolated benzoguanamine such as tetramethylol benzoguanamine, tetramethoxymethyl benzoguanamine and trimethoxymethyl benzoguanamine or an alkyl ether thereof, 2,6-bis (hydroxymethyl) -4-methylphenol or an alkyl ether thereof, 4-tert-butyl -2,6-bis (hydroxymethyl) phenol or an alkyl ether thereof, 5-ethyl-1,3-bis (hydroxymethyl) perhydro-
1,3,5-triazin-2-one (commonly known as N-ethyldimethyloltriazone) or an alkyl ether thereof,
N, N-dimethylol urea or its dialkyl ether, 3,5-bis (hydroxymethyl) perhydro-
1,3,5-oxadiazin-4-one (commonly called dimethyloluron) or an alkyl ether thereof, tetramethylol glyoxal diurein or a tetramethyl ether thereof.

On the other hand, a binder resin having a unit which undergoes a chemical change by the action of the radiation-sensitive compound after irradiation to become alkali-soluble and a unit derived from the monomer of the formula (I) is combined with the radiation-sensitive compound. And a positive resist. In some cases, the monomer itself of the formula (I) becomes a unit which undergoes a chemical change by the action of the radiation-sensitive compound after irradiation and becomes alkali-soluble. Among the units which undergo a chemical change due to the action of the radiation-sensitive compound after irradiation and become alkali-soluble, those having a polymerized unit derived from 2-alkyl-2-adamantyl (meth) acrylate have higher resolution and dry etching. Excellent in terms of resistance. The 2-alkyl-2-adamantyl (meth) acrylates can be specifically represented by the following formula (III).
A unit of the following formula (IIIa) will be formed.

[0033]

In the formula, R is hydrogen, methyl or a group having 1 to 4 carbon atoms.
And R ⁴ represents alkyl. R
^The alkyl represented by ⁴ can have, for example, about 1 to 8 carbon atoms, and is usually advantageously linear, but may be branched when it has 3 or more carbon atoms. Specific R ⁴
As methyl, ethyl, propyl, isopropyl,
Butyl and the like. In the polymerization unit of the 2-alkyl-2-adamantyl (meth) acrylate represented by the formula (IIIa), the 2-alkyl-2-adamantyl is cleaved by the action of an acid. The present invention can be applied to a positive resist using an acid generator as a radiation compound.

In addition to the polymerized unit derived from the formula (I), the binder resin has the following formula (IV) (Wherein, R ⁵ and R ⁶ are each independently hydrogen, carbon 1
Alkyl of 1-3, hydroxyalkyl of 1-3 carbons,
Represents a carboxyl, cyano or group -COOR ⁷ (R ⁷ is an alcohol residue), or R ⁵ and R ⁶ together form a carboxylic acid represented by -C (= O) OC (= O)- Forms an anhydride residue. ) And an alicyclic olefin polymer unit represented by a polymer unit of an unsaturated dicarboxylic anhydride selected from maleic anhydride and itaconic anhydride are particularly effective in increasing dry etching resistance.

R in the formula (IV)^FiveAnd R⁶Are independent of each other,
Hydrogen, alkyl having 1 to 3 carbons, hydro
Xyalkyl, carboxyl, cyano or group -CO
OR ⁷(R⁷Is an alcohol residue) or R
^FiveAnd R⁶Are joined together to form a C
Bonic anhydride residues can also be formed. R^Fiveas well as/
Or R⁶Is an alkyl.
, Ethyl, propyl, etc.
As a specific example when it is a silalkyl,
Butyl, 2-hydroxyethyl and the like. R^FivePassing
And / or R⁶Is the group -COOR⁷Is carboxy
Is an ester, and R⁷Al equivalent to
As the coal residue, for example, an optionally substituted carbon
Alkyl having a prime number of about 1 to 8, 2-oxooxolane-3
-Or -4-yl and the like.
Examples of the substituent of the killer include a hydroxyl group and an alicyclic hydrocarbon residue.
And so on. Then, R^FiveAnd / or R⁶Is -COO
R⁷In the case of a carboxylic acid ester residue represented by
Examples of methoxycarbonyl, ethoxycarbonyl
, 2-hydroxyethoxycarbonyl, tert-butoxy
Cicarbonyl, 2-oxooxolan-3-yloxy
Carbonyl, 2-oxooxolan-4-yloxyca
Rubonyl, 1,1,2-trimethylpropoxycarbonyl
1-cyclohexyl-1-methylethoxycarbony
1- (4-methylcyclohexyl) -1-methyl
Toxicarbonyl, 1- (1-adamantyl) -1-me
Tilethoxycarbonyl and the like.

Further, specific examples of the monomer for leading to the polymerized unit of the alicyclic olefin represented by the formula (IV) include the following compounds.

2-norbornene 2-hydroxy-5-norbornene 5-norbornene-2-carboxylic acid methyl 5-norbornene-2-carboxylate 5-norbornene-2-carboxylic acid-t-butyl 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, 5-norbornene-2-carboxylate 1- (4-methylcyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylate 1- (4-hydroxycyclohexyl) -1- Methylethyl, 1-methyl-1- (4-oxocyclohexyl) ethyl 5-norbornene-2-carboxylate, 1- (1-adamantyl) -1-methylethyl 5-norbornene-2-carboxylate, 5-norbornene- 1-methylcyclohexyl 2-carboxylate, 5-norbornene-2-carbo 2-methyl-2-adamantyl acid, 2-ethyl-2-adamantyl 5-norbornene-2-carboxylate 2-hydroxy-1-ethyl 5-norbornene-2-carboxylate, 5-norbornene-2-methanol, 5- Norbornene-2,
3-dicarboxylic anhydride and the like.

The polymerized unit of the unsaturated dicarboxylic anhydride is
It is selected from a polymerized unit of maleic anhydride and a polymerized unit of itaconic anhydride, and can be represented by the following formulas (V) and (VI), respectively. Specific examples of monomers for leading these polymerized units include maleic anhydride and itaconic anhydride.

[0040]

A binder resin which incorporates polymerized units derived from the monomer of the formula (I) and is itself alkali-soluble or undergoes a chemical change by the action of a radiation-sensitive compound after irradiation to become alkali-soluble. , To give some typical examples, the following formula (VI
And those having the units represented by I) to (XXVIII).

[0042]

[0043]

In the formula, R ⁸ represents a protecting group for a hydroxyl group. The hydroxyl-protecting group referred to herein may be the above-described alkyl, or any of the various groups exemplified as groups that are cleaved by the action of an acid or alkali.

The chemically amplified resist using an alkali-soluble or potentially alkali-soluble resin as a binder as described above contains a radiation-sensitive compound that is decomposed by the action of radiation. When the binder resin is alkali-soluble, using a compound having a group that can be cleaved by the action of an acid as a dissolution inhibitor, in the case of acting positively, or having a group in which the binder resin is cleaved by the action of an acid, Although it is insoluble or hardly soluble in alkali, it becomes alkali-soluble after the group that is cleaved by the action of an acid is cleaved. An acid generator that generates an acid by the action of is used. Further, in the case of a negative resist containing a binder resin which is alkali-soluble and contains a cross-linking agent, the cross-linking agent often causes a cross-linking reaction by the action of an acid. An acid generator is used. On the other hand, when the binder resin is alkali-soluble, using a compound having a group that can be cleaved by the action of a base as a dissolution inhibitor,
When the binder resin has a group that is cleaved by the action of a base and acts positively, a base generator that generates a base by the action of radiation is used as the radiation-sensitive compound.

The acid generator as a radiation-sensitive compound can be any of various compounds that generate an acid by irradiating the substance itself or a resist composition containing the substance with radiation. For example, onium salts, halogenated alkyl triazine compounds, disulfone compounds,
Examples thereof include a compound having a diazomethanesulfonyl skeleton and a sulfonic acid ester-based compound. Specific examples of such an acid generator are shown below.

Onium salts: diphenyliodonium trifluoromethanesulfonate, 4-methoxyphenylphenyliodonium hexafluoroantimonate, 4-methoxyphenylphenyliodonium trifluoromethanesulfonate, bis (4-tert-butylphenyl) iodonium tetrafluoroborate, bis (4 -Tert-butylphenyl) iodonium hexafluorophosphate, bis (4-tert-butylphenyl) iodonium hexafluoroantimonate, bis (4-tert-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyliodonium camphor) Sulfonate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroan Timmonate,
Triphenylsulfonium trifluoromethanesulfonate, 4-methoxyphenyldiphenylsulfonium hexafluoroantimonate, 4-methoxyphenyldiphenylsulfonium trifluoromethanesulfonate, p-tolyldiphenylsulfonium trifluoromethanesulfonate, 2,4,6-trimethylphenyldiphenylsulfonium trifluoromethanesulfonate , 4-tert-butylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-phenylthiophenyldiphenylsulfonium hexafluorophosphate, 4-phenylthiophenyldiphenylsulfonium hexafluoroantimonate, 1-
(2-naphthoylmethyl) thiolanium hexafluoroantimonate, 1- (2-naphthoylmethyl) thiolanium trifluoromethanesulfonate, 4-hydroxy-1-naphthyldimethylsulfonium hexafluoroantimonate, 4-hydroxy-1-naphthyldimethylsulfonium Trifluoromethanesulfonate and the like.

Halogenated alkyl triazine compound:
2-methyl-4,6-bis (trichloromethyl) -1,
3,5-triazine, 2,4,6-tris (trichloromethyl) -1,3,5-triazine, 2-phenyl-
4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-chlorophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4
-Methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxy-
1-naphthyl) -4,6-bis (trichloromethyl)-
1,3,5-triazine, 2- (benzo [d] [1,
3] dioxolan-5-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxystyryl) -4,6-bis (trichloromethyl)-
1,3,5-triazine, 2- (3,4,5-trimethoxystyryl) -4,6-bis (trichloromethyl)-
1,3,5-triazine, 2- (3,4-dimethoxystyryl) -4,6-bis (trichloromethyl) -1,
3,5-triazine, 2- (2,4-dimethoxystyryl) -4,6-bis (trichloromethyl) -1,3,5
-Triazine, 2- (2-methoxystyryl) -4,6
-Bis (trichloromethyl) -1,3,5-triazine,
2- (4-butoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-pentyloxystyryl) -4,6-bis (trichloromethyl) -1,3 , 5-triazine and the like.

Disulfone compounds: diphenyl disulfone, di-p-tolyl disulfone, phenyl p-tolyl disulfone, phenyl p-methoxyphenyl
Disulfone and the like.

Compounds having a diazomethanesulfonyl skeleton: bis (phenylsulfonyl) diazomethane, bis (4-chlorophenylsulfonyl) diazomethane, bis (p-tolylsulfonyl) diazomethane, bis (4-te
rt-butylphenylsulfonyl) diazomethane, bis (2,4-xylylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, (benzoyl) (phenylsulfonyl) diazomethane and the like.

Sulfonate compounds: 1-benzoyl-1-phenylmethyl p-toluenesulfonate (commonly called benzoin tosylate), 2-benzoyl-2-
Hydroxy-2-phenylethyl p-toluenesulfonate (commonly called α-methylol benzoin tosylate),
1,2,3-benzenetriyl trismethanesulfonate, 2,6-dinitrobenzyl p-toluenesulfonate, 2-nitrobenzyl p-toluenesulfonate, 4-nitrobenzyl p-toluenesulfonate,
N- (phenylsulfonyloxy) succinimide, N
-(Trifluoromethylsulfonyloxy) succinimide, N- (butylsulfonyloxy) succinimide, N- (10-camphorsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) -5-norbornene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy)
Naphthalimide, N- (10-camphorsulfonyloxy) naphthalimide and the like.

The base generator as a radiation-sensitive compound may also be added to the substance itself or to a resist composition containing the substance.
Various compounds capable of generating a base upon irradiation with radiation can be used. As a specific example, 2-
Nitrobenzyl cyclohexyl carbamate, 2,6
-Dinitrobenzyl cyclohexyl carbamate, formanilide, triphenylsulfonium hydroxide and the like. These compounds decompose under the action of radiation to produce amines and hydroxyl anions.

In general, in a chemically amplified resist composition using an acid generator, a basic compound, particularly a basic nitrogen-containing organic compound such as an amine, is added as a quencher to thereby provide a resist after irradiation. It is known that the performance deterioration due to the deactivation of the acid accompanying the storage can be improved. In the present invention, when an acid generator is used as the radiation-sensitive compound, it is preferable to mix such a basic compound. Specific examples of the basic compound used for the quencher include those represented by the following formulas.

[0054]

[0055]

Where R¹¹And R¹²Is independent of the water
Alkyl, cycloalkyl optionally substituted with hydroxyl,
Alkyl or aryl;¹³, R¹⁴And R^FifteenAre each other
Independently, an alkyl optionally substituted with hydrogen or a hydroxyl group
Represents cycloalkyl, aryl or alkoxy,
R¹⁶Is an alkyl or cycloalkyl which may be substituted with a hydroxyl group.
A represents alkyl, alkylene, carbo
Nil, imino, disulfide, sulfide or secondary amino
Represents R¹¹~ R¹⁶Alkyl and R represented by ¹³~ R
^FifteenThe alkoxy represented by each has about 1 to 6 carbon atoms
And R¹¹~ R¹⁶Cycloalkyl represented by
Can have about 5 to 10 carbon atoms, and R
¹¹~ R^FifteenIs an aryl group having about 6 to 10 carbon atoms.
There can be. The alkylene represented by A is
It can have about 1 to 6 carbon atoms, and can be branched
May be.

Further, a hindered amine compound having a piperidine skeleton as disclosed in JP-A-11-52575 can be used as the quencher.

The resist composition of the present invention contains the binder component in the range of about 60 to 99.9% by weight and the radiation-sensitive compound in the range of about 0.1 to 20% by weight based on the total solid content. Is preferred. A positive resist,
When a dissolution inhibitor is used, the number of the binder components is 5 to 4 based on the total solid content of the resist composition.
It is appropriate to contain it in the range of about 0% by weight. In the case of a negative resist, it is appropriate to contain a crosslinking agent in the range of about 1 to 30% by weight based on the total solid content of the resist composition. When the binder resin is alkali-soluble by the action of the radiation-sensitive compound after irradiation, acts positively, and when the majority of the resist composition is occupied by the binder resin and the radiation-sensitive compound,
It is appropriate that the amount of the binder resin is about 80% by weight or more based on the total solid content in the composition.
When the radiation-sensitive compound is an acid generator and a basic compound is used as the quencher, it is contained in an amount of about 0.01 to 1% by weight based on the total solid weight of the resist composition. Is preferred. This composition also comprises
If necessary, various additives such as sensitizers, other resins, surfactants, stabilizers and dyes can be contained in small amounts.

The resist composition of the present invention usually becomes a resist solution in a state where the above components are dissolved in a solvent, and is applied to a substrate such as a silicon wafer by a conventional method such as spin coating. The solvent used here may be any as long as it dissolves each component, has an appropriate drying rate, and gives a uniform and smooth coating film after the solvent evaporates. A solvent generally used in this field is used. Can. For example,
Glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate, ethers such as diethylene glycol dimethyl ether,
Esters such as ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; and cyclic esters such as γ-butyrolactone. . These solvents can be used alone or in combination of two or more.

The resist film applied on the substrate and dried is subjected to an exposure treatment for patterning, and then to a heat treatment for accelerating a deprotection group reaction or a cross-linking reaction. Is developed. The alkaline developer used here can be various alkaline aqueous solutions used in this field, but generally, aqueous solutions of tetramethylammonium hydroxide and (2-hydroxyethyl) trimethylammonium hydroxide (commonly known as choline) are used. Often used.

[0061]

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. Parts in the examples are by weight unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography using polystyrene as a standard.

Synthesis Example 1 of Monomer (Synthesis of 2-methyl-2-adamantyl methacrylate) 83.1 g of 2-methyl-2-adamantanol and 101 g of triethylamine were charged, and 200 g of methyl isobutyl ketone was added to prepare a solution. There, 78.4 g of methacrylic acid chloride (2
-Methyl-2-adamantanol) was added dropwise, and the mixture was stirred at room temperature for about 10 hours. After filtration, the organic layer was washed with a 5% by weight aqueous sodium bicarbonate solution, and then washed twice with water. After concentrating the organic layer, the organic layer was distilled under reduced pressure to give 2-methyl methacrylate represented by the following formula.
2-Adamantyl was obtained.

[0063]

Synthesis Example 2 of Monomer (Synthesis of α-methacryloyloxy-γ-butyrolactone) 100 g of α-bromo-γ-butyrolactone and 104.4 g of methacrylic acid (α-
(2.0 mol times with respect to bromo-γ-butyrolactone), and methylisobutyl ketone, which was 3 times the weight of α-bromo-γ-butyrolactone, was added to form a solution. 183.6 g of triethylamine (3.0 mol times based on α-bromo-γ-butyrolactone) was added dropwise thereto, and the mixture was stirred at room temperature for about 10 hours. After filtration, the organic layer was washed with a 5% by weight aqueous sodium bicarbonate solution, and then washed twice with water. The organic layer was concentrated to obtain α-methacryloyloxy-γ-butyrolactone represented by the following formula.

[0065]

Resin Synthesis Example (A1) A resin stirrer equipped with a magnetic stirrer, a cooling pipe, a thermometer, and a nitrogen introduction pipe
In a 0 mL three-necked flask, 5.81 g of 2-trifluoromethylacrylic acid [obtained from Kanto Chemical Co., Ltd.]
(2-Methyladamantane) 9.72 g of methacrylic acid ester and 10.5 g of methyl isobutyl ketone were added, and after purging with nitrogen, the temperature was raised to 80 ° C., and 0.34 g of azobisisobutyronitrile was added to 10 g of methyl isobutyl ketone. The dissolved solution was added dropwise over 30 minutes. Thereafter, the temperature was kept at 80 ° C. for 8 hours. This reaction solution is added to 30
After cooling to ℃, 7.5 g of triethylamine was added dropwise over 1 hour. Then, at 35 to 45 ° C, α-bromo-γ
8.56 g of butyrolactone was added dropwise over 2 hours.
The reaction was performed for 8 hours while maintaining the temperature at 45 ° C. Thereafter, the mixture was filtered, and the filtrate was washed with water six times. After concentrating the organic layer after washing with water 2-
Heptanone was added and concentrated, and the mixture was added dropwise to 65% methanol water, and the precipitated resin was filtered and dried to obtain a resin A1. 14.05 g of yield.

Example of Resin Synthesis (A2) A resin stirrer equipped with a magnetic stirrer, a cooling pipe, a thermometer, and a nitrogen inlet pipe
In a 0 mL three-necked flask, 15.54 g of t-butyl 5-norbornene-2-carboxylate, 7.84 g of maleic anhydride, 9.44 g of hexafluoroisopropyl methacrylate, and 22 g of methyl isobutyl ketone were charged. After purging with nitrogen, the temperature was raised to 80 ° C., and a solution of 0.82 g of azobisisobutyronitrile dissolved in 11 g of methyl isobutyl ketone was added dropwise over 30 minutes. Thereafter, the temperature was kept at 80 ° C. for 8 hours. Thereafter, the reaction solution was poured into a mixed solution of 250 g of methanol and 100 g of water, and the precipitated resin was dissolved in propylene glycol methyl ether acetate and concentrated to obtain a resin solution.
64.55 g of yield. 21.40% solids. This is resin A
Let it be 2.

Resin Synthesis Example (A3) A 10-cell cooling tube, a thermometer, a magnetic stirrer, and a dropping funnel were provided.
In a 0 ml three-necked flask, 8.59 g of 2-methyladamantyl bicyclo [2.2.1] hept-5-ene-2-carboxylate (NB-2MAd), 2.94 g of maleic anhydride (MA), (Perfluoro-3-methylbutyl) -2-hydroxypropyl acrylate (T
5.97 g of FMC70OHAA) and 10 g of 4-methyl-2-pentanone were impregnated and subjected to nitrogen substitution. Then 8
The temperature was raised to 0 ° C., and 0.31 g of AIBN dissolved in 7 g of 4-methyl-2-pentanone was added dropwise over 30 minutes.
Thereafter, the temperature was kept at 80 ° C. for 8 hours. After cooling, methanol 30
The reaction solution was added dropwise to 0 ml, and the precipitated resin was obtained by filtration. Drying under reduced pressure at 40 ° C. was performed for 8 hours to obtain 10.2 g of a resin. Polystyrene equivalent weight average molecular weight (Mw) 640
0. This is called resin A3.

Resin Synthesis Examples (A4, A5, X1) Resins shown in the following table were obtained by the same operation as in the synthesis example of resin A3.

[0070] Example charged monomers Mw resin synthesis A4 NB-TB / MA / TFMC70HAA = 40/40/20 6100 Resin Synthesis Example A5 NB-2Mad / MA / TFMC70HAA = 45/45/10 5500 Resin Synthesis Example X1 NB-TB / MA = 50/50 5400 NB-TB: 2-methylpropylbicyclo [2.2.1] hept-5-en-2-carboxylate

Example of Resin Synthesis (A6) A 10-unit equipped with a cooling pipe, a thermometer, a magnetic stirrer, and a dropping funnel
In a 0 ml three-necked flask, add 2-adamantylpropyl
Bicyclo [2.2.1] hept-5-ene-2-carboxylate (NB-AdTB) 9.43 g, MA
94 g, 5.97 g of TFMC7OHAA, and 10 g of 4-methyl-2-pentanone were subjected to nitrogen substitution. Thereafter, the temperature was raised to 80 ° C., and 0.31 g of AIBN dissolved in 7 g of 4-methyl-2-pentanone was added dropwise over 30 minutes. Thereafter, the temperature was kept at 80 ° C. for 8 hours. After cooling, the reaction solution was added dropwise to 300 ml of hexane, and the precipitated resin was obtained by filtration. The resin was dried under reduced pressure at 40 ° C. for 8 hours to obtain a resin 7.3
g was obtained. Polystyrene equivalent weight average molecular weight (Mw) 1
0900. This is called resin A6.

Resin Synthesis Example (A7) The molar ratio of the charged monomers was set to NB-AdTB / MA / TFMC7OHMA = 40.
A resin was obtained by performing the same operation as in Resin Synthesis Example A6 except for changing the ratio to / 40/20. Polystyrene equivalent weight average molecular weight (Mw) 16700. This is called resin A7.

Example of Resin Synthesis (A8) A 10-unit equipped with a cooling pipe, a thermometer, a magnetic stirrer, and a dropping funnel
In a 0 ml three-necked flask, 7.03 g of 2-adamantyl methacrylate (2MAdMA), TFMC7OH
12.37 g of MA, 4-methyl-2-pentanone 10
g was replaced with nitrogen. Thereafter, the temperature was raised to 80 ° C., and AI dissolved in 7 g of 4-methyl-2-pentanone was dissolved.
0.25 g of BN was added dropwise over 30 minutes. Then 80 ° C
For 8 hours. After cooling, the reaction solution was added dropwise to 300 ml of hexane, and the precipitated resin was obtained by filtration. Drying under reduced pressure at 40 ° C. was performed for 8 hours to obtain 10.5 g of a resin. Polystyrene equivalent weight average molecular weight (Mw) 24000. This is resin A
8 is assumed.

Resin Synthesis Example (X2) 2-methyl-2-adamantyl methacrylate and α-methacryloyloxy-γ-butyrolactone were charged at a molar ratio of 5: 5 (15.0 g: 11.7 g), and all monomers were charged. A solution was added by adding 2 weight times methyl isobutyl ketone. Thereto, azobisisobutyronitrile as an initiator was added at 2 mol% based on the total amount of monomers, and the mixture was heated at 80 ° C. for about 8 hours. Thereafter, an operation of pouring the reaction solution into a large amount of heptane to precipitate was performed three times, and purification was performed. As a result, a copolymer having a weight average molecular weight of 10,000 was obtained. This is resin X2
And

Examples 1 to 8 and Comparative Examples 1 and 2 The following components were mixed and filtered through a fluorine resin filter having a pore size of 0.2 μm to prepare a resist solution.

Resin 10 parts Acid generator: p-tolyl diphenylsulfonium trifluoromethanesulfonate 0.2 part [“MDS-205” obtained from Midori Kagaku Co., Ltd.] Quencher: 2,6-diisopropylaniline 0.015 part Solvent: propylene glycol monomethyl 100 parts of ether acetate

The resist solution prepared above was applied to a silicon wafer treated with hexamethyldisilazane at 23 ° C. for 20 seconds so that the film thickness after drying was 0.1 μm. The prebaking was performed on a direct hot plate at 120 ° C. for 60 seconds. A simple F ₂ excimer laser exposure machine [“VUVES-
4500 "] to perform open frame exposure while changing the exposure stepwise. After the exposure, a post-exposure bake (PEB) at 120 ° C. for 60 seconds was performed on a direct hot plate, followed by 2. Paddle development was performed for 60 seconds with a 38% by weight aqueous solution of tetramethylammonium hydroxide.
The minimum exposure amount (film sensitivity) at which the resist was removed from the film was determined, and the results shown in Table 1 were obtained.

On the other hand, on a magnesium fluoride wafer, a solution prepared by dissolving only the previously prepared resist solution and resin in a propylene glycol monomethyl ether acetate solvent was dried to a thickness of 0.1 μm.
m, and prebaked on a direct hot plate at 120 ° C. for 60 seconds to form a resist film. The transmittance of the thus formed resist film at a wavelength of 157 nm was measured using the transmittance measurement function of the simple F ₂ excimer laser exposure machine used above,
The results shown in Table 1 were obtained.

[0079]

[Table 1] 感 度 Resin film removal sensitivity Transmittance Resin only Resist ━━━━━━━━ ━━━━━━━━━━━━━━━━━━━━━ example ^{1 A1 2 mJ / cm 2 35} % 35% example ^{2 A2 5 mJ / cm 2 36} % 33% example 3 ^{A3 3 mJ / cm 2 32%} 30% example ^{4 A4 4.5 mJ / cm 2 38} % 36% example ^{5 A5 4 mJ / cm 2 28} % 26% example ^{6 A6 2.5 mJ / cm 2 33} % 31% embodiment example ^{7 A7 3.5 mJ / cm 2 30} % 29% example ^{8 A8 1 mJ / cm 2 44} % 43% Comparative example ^{1 X1 8 mJ / cm 2 26} % 25% Comparative example ^{2 X2 3 mJ / cm 2 25} % 25 % ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Resin Synthesis Example (A9) A resin stirrer equipped with a magnetic stirrer, a cooling pipe, a thermometer, and a nitrogen inlet pipe
In a 0 mL flask, methacrylic acid 3- (perfluoro-
10.31 g of 3-methylbutyl) -2-hydroxypropyl [obtained from Daikin Chemicals Sales Co., Ltd.], 17.63 g of pt-butoxystyrene, and 31 g of methyl isobutyl ketone were charged. After purging with nitrogen, the temperature was raised to 80 ° C., and a solution of 0.82 g of azobisisobutyronitrile dissolved in 11 g of methyl isobutyl ketone was added dropwise over 30 minutes. Thereafter, the temperature was kept at 80 ° C. for 8 hours. Thereafter, the reaction solution was poured into a mixed solution of 250 g of methanol and 100 g of water, and the precipitated resin was dissolved in methyl isobutyl ketone and concentrated to obtain a resin solution of 57.6 g. 62.8 methyl isobutyl ketone was added to the resin solution.
g, 3.0 g of p-toluenesulfonic acid and 9.7 g of water were added and the mixture was kept at 70 ° C. for 15 hours. The reaction solution was washed 5 times with water and concentrated, and then 300 g of propylene glycol methyl ether acetate was added, followed by further concentration to obtain a resin solution.
65.3 g of yield. 27.21% solids. Weight average molecular weight 14900. This resin is referred to as resin A9.

Resin Synthesis Example (A10) A resin stirrer equipped with a magnetic stirrer, a cooling pipe, a thermometer, and a nitrogen introduction pipe
In a 0 mL flask, add methyl isobutyl ketone 26.81.
g. After replacing with nitrogen, the temperature was raised to 84 ° C,
Separately, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl methacrylate [Daikin Chemicals Sales
9.89 g, pt-butoxystyrene 16.92 g, azobisisobutyronitrile 1.97 g
Was dissolved in 26.81 g of methyl isobutyl ketone and added dropwise over 1 hour. After that, keep the temperature at 84 ° C 8
Incubated for hours. Thereafter, 247.23 g of methanol and 1 of water
The reaction solution was dropped into 23.61 g of the mixed solution over 30 minutes, and the obtained resin was dissolved in methyl isobutyl ketone.
By concentrating, 67.03 g of a resin solution was obtained. To this resin solution, 93.52 g of methyl isobutyl ketone, p
-3.49 g of toluenesulfonic acid and 11.26 g of water were added, and the mixture was kept at 70 ° C for 15 hours. The reaction solution was washed with water 5 times, concentrated, and then dropped into 446.88 g of n-heptane over 30 minutes. The obtained resin was filtered and dried under reduced pressure.
A resin was obtained. 17.07 g. Weight average molecular weight 440
0. This is called resin A10.

Resin X3: Poly (p-produced by Nippon Soda Co., Ltd.)
A resin in which the hydroxyl group of vinylphenol (product name "VP-2500") is protected with an isopropyl group at an average protection rate of 20%.

Examples 9 and 10 and Comparative Example 3 The following components were mixed and filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution.

Resin (as solid content) 10 parts Crosslinking agent: hexamethoxymethylmelamine 0.5 parts Acid generator: N- (isopropylsulfonyloxy) succinimide 1.1 parts (Plus resin carry-in): 100 parts of propylene glycol monomethyl ether acetate

A silicon wafer on which an organic anti-reflective coating having a thickness of 600 mm was formed by applying DUV-42, a composition for organic anti-reflective coating manufactured by Brewer, and baking at 215 ° C. for 60 seconds. Then, the resist solution prepared above was spin-coated so that the film thickness after drying was 0.523 μm, and after the resist solution was applied, the resist solution was prebaked on a direct hot plate at 100 ° C. for 60 seconds. A KrF excimer stepper (“NSR 2205EX-12B” manufactured by Nikon Corporation, NA = 0.55, σ = 0.55) is formed on the wafer on which the resist film is formed.
8], the line and space pattern was exposed while changing the exposure amount stepwise. After the exposure, post-exposure baking (PEB) was performed on a hot plate at 105 ° C. for 60 seconds, and paddle development was performed with a 2.38 wt% aqueous solution of tetramethylammonium hydroxide for 60 seconds. The line and space pattern after development was observed with a scanning electron microscope, and the effective sensitivity and resolution were examined by the following methods.

Effective sensitivity: Displayed at an exposure amount at which a 0.20 μm line and space pattern becomes 1: 1.

Resolution: Displayed with the minimum size of a line and space pattern separated by the exposure amount of the effective sensitivity.

On the other hand, on a magnesium fluoride wafer, a solution prepared by dissolving only the previously prepared resist solution and resin in a propylene glycol monomethyl ether acetate solvent was dried to a thickness of 0.1 μm.
m, and prebaked on a direct hot plate at 100 ° C. for 60 seconds to form a resist film. The transmittance of the resist film thus formed at a wavelength of 157 nm was measured using a simple F ₂ excimer laser exposure machine (VUVES-450 manufactured by Lithotech Japan).
The measurement was performed using the transmittance measurement function of 0), and the results shown in Table 2 were obtained.

[0089]

[Table 2] 樹脂 Resin transmittance Effective sensitivity (KrF) Resolution ( KrF) Resin only Resist ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Example 9 A9 40% 40% 18 mJ / cm ² 0.16 μm Example 10 A10 39% 38% 90 mJ / cm ² 0.15 μm ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━比較 Comparative Example 3 X3 27% 27% 27 mJ / cm ² 0.16μm ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ━━━━━━━━

Resin Synthesis Example (A11) In a four-necked flask equipped with a magnetic stirrer, a nitrogen inlet tube, a Dimroth condenser, a thermometer and a dropping funnel, 9.37 g of 2-methyl-2-adamantyl methacrylate, methacrylic acid 9.44 g of 1-trifluoromethyl-2,2,2-trifluoroethyl [obtained from Tokyo Chemical Industry Co., Ltd.], 0.263 g of azobisisobutyronitrile, and 40.9 g of methyl isobutyl ketone were charged, and the atmosphere was changed. It was replaced with nitrogen. Thereafter, the temperature was raised to 80 ° C. using an oil bath while flowing nitrogen into the system, and the temperature was maintained for about 7 hours. After cooling, the reaction solution was added dropwise to 1 dm ³ of methanol with stirring.
After stirring for 30 minutes, the mixture was filtered to obtain 25.8 g of a white powder. This white powder was dried under reduced pressure at 60 ° C. for about 6 hours to obtain 8.4 g of a resin. Yield 45%. Weight average molecular weight 10200. This is called resin A11.

Example 11 and Comparative Example 4 The following components were mixed and filtered through a fluorine resin filter having a pore size of 0.2 μm to prepare a resist solution.

Resin (in terms of solid content) 10 parts Acid generator: p-tolyl diphenylsulfonium trifluoromethanesulfonate 0.2 parts [“MDS-205” obtained from Midori Kagaku Co., Ltd.] Quencher: dicyclohexylmethylamine 0.015 parts Example 2-Heptanone 100 parts Comparative example Perylene glycol monomethyl ether acetate / γ-butylolactone (95/5) 100 parts

"DUV-30J-14", an organic anti-reflective coating composition manufactured by Brewer, was applied and baked at 215 ° C for 60 seconds to form an organic anti-reflective coating having a thickness of 1,600Å. The resist solution prepared above was spin-coated on the silicon wafer so that the film thickness after drying was 0.39 μm. After the application of the resist solution, prebaking was performed on a direct hot plate at 120 ° C. for 60 seconds. An ArF excimer stepper [“NSR ArF” manufactured by Nikon Corporation, NA = 0.55, σ =
0.6], and the line and space pattern was exposed while changing the exposure amount stepwise. After the exposure, a post-exposure bake (PEB) was performed on a hot plate at 120 ° C. for 60 seconds for 60 seconds, and then a 2.38% by weight aqueous solution of tetramethylammonium hydroxide was added.
Paddle development for 0 seconds was performed. The line and space pattern after development was observed with a scanning electron microscope, and the effective sensitivity and resolution were examined by the following methods. Table 3 shows the results.

Effective sensitivity: Display was performed at an exposure amount at which a 0.18 μm line and space pattern was 1: 1.

Resolution: The minimum size of the line and space pattern separated by the exposure amount of the effective sensitivity was displayed.

On the other hand, on a magnesium fluoride wafer, a solution prepared by dissolving only the previously prepared resist solution and resin in propylene glycol monomethyl ether acetate solvent was dried to a thickness of 0.1 μm.
m, and prebaked on a direct hot plate at 120 ° C. for 60 seconds to form a resist film. The transmittance of the resist film thus formed at a wavelength of 157 nm was measured using a simple F ₂ excimer laser exposure machine [“VU obtained from Lithotech Japan Co., Ltd.”
VES-4500 "], and the results shown in Table 3 were obtained.

[0097]

[Table 3] 樹脂 Resin transmittance Effective sensitivity Resolution Resin only resist ━ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Example 11 A11 30% 30% 42 mJ / cm ² 0.16 μm ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Comparative example 4 X2 25% 25% 36mJ / cm 2 0.16μm ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Resin Synthesis Example (A12) 100 m provided with a stirring rod, a cooling pipe, a thermometer, and a nitrogen introduction pipe
9.73 g of p-acetoxystyrene in an L flask,
2.56 g of t-butyl acrylate, 3-methacrylic acid
7.96 g of (perfluoro-3-methylbutyl) -2-hydroxypropyl [obtained from Daikin Chemicals Sales Co., Ltd.]
And isopropanol (13.51 g) were charged and purged with nitrogen, and the temperature was raised to 80 ° C. Separately, a solution obtained by dissolving 0.41 g of azobisisobutyronitrile in 6.75 g of isopropanol was dropped over 0.5 hour. After keeping the temperature at 80 ° C. for 6 hours, the mixture was dropped into a mixed solution of methanol and water for crystallization, filtered and dried to obtain 15.69 g of a resin. 15.69 g of the obtained resin and 4-dimethylaminopyridine
57 g and 47.07 g of methanol were charged into a 100 mL flask equipped with a stirring rod, a cooling tube, a thermometer, and a nitrogen inlet tube, and aged for 15 hours under reflux. After cooling, glacial acetic acid 0.9
The mixture was neutralized with 3 g, charged in 784.50 g of water, crystallized, and crystals were taken out by filtration. Thereafter, the crystals were dissolved in acetone, charged with water for crystallization, and the crystals were taken out by filtration. This operation was repeated three times in total, and the obtained crystals were dried to obtain 12.59 g of a resin. The weight average molecular weight was 37000, and the degree of dispersion was 3.72 (GPC method: converted to polystyrene). This is called resin A12.

Resin Synthesis Example (A13) 100 m provided with a stirring rod, a cooling pipe, a thermometer, and a nitrogen introduction pipe
9.73 g of p-acetoxystyrene in an L flask,
4.69 g of 2-methyl-2-adamantyl methacrylate
, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl methacrylate [Daikin Chemicals Sales
7.96 g and 13.9 g of isopropanol
After charging 2 g, the atmosphere was replaced with nitrogen and the temperature was raised to 80 ° C. Separately, a solution obtained by dissolving 0.41 g of azobisisobutyronitrile in 7.46 g of isopropanol was dropped over 0.5 hour. After keeping the temperature at 80 ° C. for 6 hours, the mixture was dropped into a mixture of methanol and water to cause crystallization, followed by filtration to obtain 22.08 g of a resin. 22.08 g of the obtained resin, 2.21 g of 4-dimethylaminopyridine and 110 g of methanol were charged into a 300 mL flask equipped with a stirring rod, a cooling tube, a thermometer, and a nitrogen inlet tube, and aged for 15 hours under reflux. After cooling, the mixture was neutralized with 2.21 g of glacial acetic acid, charged in 2000 g of water, crystallized, and crystals were taken out by filtration. Thereafter, the crystals were dissolved in acetone, charged with water for crystallization, and the crystals were taken out by filtration. This operation was repeated three times in total, and the obtained crystals were dried to obtain 11.51 g of a resin. The weight average molecular weight is 30,900, and the degree of dispersion is 1.99.
(GPC method: converted into polystyrene). This is called resin A13.

Resin Synthesis Example (X4) The weight average molecular weight was 12600 and the dispersity was 1.87 (GPC
The copolymerization ratio of t-butyl acrylate, styrene and p-hydroxystyrene copolymer (TSM-4 manufactured by Maruzen Kagaku Co., Ltd.) was determined by nuclear magnetic resonance ( ¹³
(C-NMR) was determined to be about 20:20:60 by a spectrometer.

Resin Synthesis Example (X5) (1) 2-adamantyl methacrylate-2 was placed in a flask.
-24.6 g (0.105 mol) of -methyl, 39.7 g (0.245 mol) of p-acetoxystyrene, and 128.6 g of isopropanol were charged and replaced with nitrogen, and the temperature was raised to 75 ° C. 4.84 g (0.021 g) of dimethyl 2,2-azobis (2-methylpropionate) was added to the solution.
Mol) was dissolved in 9.7 g of isopropanol and added dropwise. After aging at 75 ° C. for about 0.5 hours and under reflux for about 11 hours, the mixture was diluted with acetone, charged into heptane, crystallized, crystals were taken out by filtration, and the obtained crystals were dried. The resulting 2-adamantyl-2-methacrylate
Crystals of methyl and p-acetoxystyrene copolymer are 5
4.1 g.

(2) Into a flask, 53.2 g (0.29 mol as a monomer unit) of 2-adamantyl-2-methyl methacrylate and p-acetoxystyrene copolymer (30:70) obtained above and 4 5.3 g (0.043 mol) of dimethylaminopyridine and 159.5 of methanol
g, and aged for 20 hours under reflux. After cooling, the mixture was neutralized with 3.92 g (0.065 mol) of glacial acetic acid, charged in water, crystallized, and crystals were taken out by filtration. Thereafter, the crystals were dissolved in acetone, charged in water, crystallized, and the crystals were taken out by filtration.
After repeating twice, the obtained crystals were dried. The obtained crystals of 2-adamantyl-2-methyl methacrylate and p-hydroxystyrene copolymer weighed 41.2 g. The weight average molecular weight was 8100 and the degree of dispersion was 1.68 (GP
C method: polystyrene conversion), and the copolymerization ratio was determined to be about 30:70 by a nuclear magnetic resonance (< ¹³ > C-NMR) spectrometer. This resin is referred to as resin X5.

Resin Synthesis Example (X6) (1) 2-adamantyl methacrylate
Then, 16.4 g (0.07 mol) of -methyl, 45.4 g (0.28 mol) of p-acetoxystyrene and 123.6 g of isopropanol were charged and the atmosphere was replaced with nitrogen. Add dimethyl 2'2-azobis (2-
4.84 g (0.021 mol) of methyl propionate)
Was dissolved in 9.7 g of isopropanol and added dropwise.
After aging at 75 ° C. for about 0.5 hours and under reflux for about 11 hours, the mixture was diluted with acetone, charged into heptane, crystallized, crystals were taken out by filtration, and the obtained crystals were dried. The obtained crystals of 2-adamantyl-2-methyl methacrylate and p-acetoxystyrene copolymer were 54.2.
g.

(2) Into a flask, 53.0 g (0.30 mol as a monomer unit) of 2-adamantyl-2-methyl methacrylate obtained above and p-acetoxystyrene copolymer (20:80) were added. -Dimethylaminopyridine 5.3 g (0.043 mol) and methanol 159.0
g, and aged for 20 hours under reflux. After cooling, the mixture was neutralized with 3.13 g (0.052 mol) of glacial acetic acid, charged in water, crystallized, and crystals were taken out by filtration. Thereafter, the crystals were dissolved in acetone, charged in water, crystallized, and the crystals were taken out by filtration.
After repeating twice, the obtained crystals were dried. The weight of the obtained crystals of 2-adamantyl-2-methyl methacrylate and p-hydroxystyrene copolymer was 37.8 g. The weight average molecular weight is about 7900, and the degree of dispersion is 1.72 (G
PC method: converted to polystyrene), and the copolymerization ratio was determined to be about 20:80 by a nuclear magnetic resonance (< ¹³ > C-NMR) spectrometer. This resin is referred to as resin X6.

Example 12 and Comparative Example 5 The following components were mixed and filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution.

Resin 10 parts Acid generator: bis (4-t-butylphenyliothonium camphorsulfonate 0.52 parts Quencher: triisofluorophenolamine 0.052 parts Solvent: ethyl lactate 100 parts

Example 13 and Comparative Example 6 The following components were mixed and filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution.

Resin 10 parts Acid generator: Bis (4-t-butylphenyliothonium camphorsulfonate 0.52 parts Quencher: 2,6-diisopropylfluoroaniline 0.052 parts Solvent: Methyl amyl ketone 100 parts

The resist solution prepared above was applied to a silicon wafer treated with hexamethyldisilazane at 23 ° C. for 20 seconds so that the film thickness after drying was 0.1 μm. Prebaking was performed on a direct hot plate at 130 ° C. for 60 seconds. A simple F ₂ excimer laser exposure machine [“VUVES-
4500 "] to perform open-frame exposure while changing the exposure amount stepwise. After the exposure, post-exposure bake (PEB) was performed on a direct hot plate at 140 ° C. for 60 seconds, followed by 2. Paddle development was performed for 60 seconds with a 38% by weight aqueous solution of tetramethylammonium hydroxide.
The minimum exposure amount (film sensitivity) at which the resist was removed from the film was determined, and the results shown in Table 4 were obtained.

On the other hand, on a magnesium fluoride wafer, a solution prepared by dissolving only the previously prepared resist solution and resin in propylene glycol monomethyl ether acetate solvent was dried to a thickness of 0.1 μm.
m, and prebaked on a direct hot plate at 130 ° C. for 60 seconds to form a resist film. The transmittance of the resist film thus formed at a wavelength of 157 nm was measured using a vacuum ultraviolet spectrometer (VUV-200 manufactured by JASCO Corporation), and the results shown in Table 4 were obtained.

[0111]

[Table 4] 感 度 Resin film removal sensitivity Transmittance Resin only Resist の み━━━━━━━━━━━━━━━━━━━━━ Example 12 A12 2.5 mJ / cm ² 30% 31% Example 13 A13 0.5 mJ / cm ² 27% 27% ━━━比較 Comparative Example 5 X4 ² mJ / cm ² 24% 25% Comparative Example 6 X5 / X6 = 1 3 mJ / cm ² 21% 22% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

[0112]

The resist composition of the present invention exhibits a high transmittance when exposed to light using a light source having a wavelength of 170 nm or less, for example, an F ₂ excimer laser having a wavelength of 157 nm.
Since the resolution in F and ArF exposure is high and has a sufficient contrast, it can exhibit excellent performance as a chemically amplified resist using a light source having a wavelength of 170 nm or less.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/00 C08K 5/00 C08L 33/06 C08L 33/06 33/16 33/16 35/00 35 / 00 45/00 45/00 G03F 7/004 503 G03F 7/004 503A 503B 7/038 601 7/038 601 H01L 21/027 H01L 21/30 502R (31) Priority claim number Japanese Patent Application No. 2000-1119397 (P2000- (119397) (32) Priority Date April 20, 2000 (April 20, 2000) (33) Priority Country Japan (JP) (72) Inventor Yoshiko Miya 3-chome, Kasuga, Konohana-ku, Osaka-shi No. 98 Sumitomo Chemical Co., Ltd. (72) Inventor Hiroki Inoue 3-1-1, Kasuganaka, Konohana-ku, Osaka F-term in Sumitomo Chemical Co., Ltd. 2H025 AB16 AC03 AD01 AD03 BE00 BE07 BE10 BF02 BF08 BF09 BF11 BG00 CB43 C C20 FA17 4J002 BG041 BG051 BG081 BH021 BK001 EU186 EV166 EV216 EV246 EV256 EW046 EY016 EY026 FD206 GP03 4J100 AB07S AK31R AK32R AL08P AL08Q AL24P AL26P AR11R BA03P BA03PBABC BC11 BA03PBABCB11PBA BCBC

Claims (9)

[Claims] A binder resin and a radiation-sensitive compound, wherein the binder resin itself is alkali-soluble or undergoes a chemical change by the action of the radiation-sensitive compound after irradiation to become alkali-soluble. Then, the following formula (I) (Wherein Q represents hydrogen, methyl or fluoroalkyl having 1 to 4 carbons, and R ¹ is halogen, alkyl having 1 to 14 carbons which may be substituted with a hydroxyl group or an alicyclic ring, or halogen, hydroxyl, represents an alicyclic ring or lactone ring optionally substituted with an alkyl group, Q, R ¹
At least one has at least one fluorine atom. A chemically amplified resist composition having a polymerized unit derived from the monomer represented by the formula (1). 2. The composition according to claim 1, wherein Q in the formula (I) is trifluoromethyl. 3. The composition according to claim 1, wherein R ¹ in the formula (I) is a fluoroalkyl having 1 to 14 carbon atoms which may have at least one fluorine-substituted hydroxyl group. 4. A fluoroalkyl having 1 to 14 carbon atoms which may have at least one fluorine-substituted hydroxyl group is represented by the following formula (II): (In the formula, R ² represents hydrogen, alkyl or fluoroalkyl, R ³ represents fluoroalkyl, and the total carbon number of R ² and R ³ is 1 to 11. n represents 0 or 1.)
The composition according to claim 3, which is a group represented by the formula: 5. The composition according to claim 1, wherein the radiation-sensitive compound is an active compound that generates an acid or a base by the action of radiation and acts positively. 6. The method according to claim 5, wherein the binder resin has a group which is cleaved by the action of an acid or a base, and is itself insoluble or hardly soluble in alkali, but becomes alkali-soluble by the action of an acid or base. Composition. 7. The polymer of claim 1, wherein the binder resin comprises, in addition to polymerized units derived from the monomer of formula (I), (Wherein, R represents hydrogen or methyl, and R ⁴ represents alkyl) 2-alkyl- (meth) acrylate-
7. The composition according to claim 5, which has a polymerized unit derived from 2-adamantyl, and wherein the radiation-sensitive compound is an acid generator that generates an acid by the action of radiation. 8. The polymer according to claim 1, wherein the binder resin comprises, in addition to the polymerized units derived from the monomer of formula (I), (Wherein, R ⁵ and R ⁶ are each independently hydrogen, carbon 1
Alkyl of 1-3, hydroxyalkyl of 1-3 carbons,
Represents a carboxyl, cyano or group -COOR ⁷ (R ⁷ is an alcohol residue), or R ⁵ and R ⁶ together form a carboxylic acid represented by -C (= O) OC (= O)- Forms an anhydride residue. The composition according to any one of claims 5 to 7, comprising a polymerized unit of an alicyclic olefin represented by a polymerized unit of an unsaturated dicarboxylic anhydride selected from maleic anhydride and itaconic anhydride. 9. The composition according to claim 1, wherein the binder resin itself is alkali-soluble, further contains a crosslinking agent, and acts negatively.