JP2006133803A5 - - Google Patents

Description

Radiation sensitive resin composition

  The present invention relates to a radiation-sensitive resin composition suitable for fine processing using radiation such as deep ultraviolet rays, electron beams, and X-rays.

In recent years, demands for higher density and higher integration of LSIs (highly integrated circuits) are increasing, and along with this, miniaturization of wiring patterns is also progressing rapidly.
As one of the means that can cope with such miniaturization of the wiring pattern, there is a method of shortening the radiation used in the lithography process. In recent years, g-line (wavelength 436 nm), i-line (wavelength 365 nm), etc. Instead of ultraviolet rays, far ultraviolet rays such as KrF excimer laser (wavelength 248 nm) or ArF excimer laser (wavelength 193 nm), electron beams, X-rays and the like are used.
By the way, in the conventional resist composition, a novolak resin, poly (vinylphenol), or the like has been used as a resin component, but these materials contain an aromatic ring in the structure and have strong absorption at a wavelength of 193 nm. Therefore, the lithography process using the ArF excimer laser cannot obtain high accuracy corresponding to high sensitivity, high resolution, and high aspect ratio.
Therefore, there is a demand for a resist resin material that is transparent to a wavelength of 193 nm or less and has dry etching resistance equal to or higher than that of an aromatic ring. One of them is a siloxane polymer, and MIT RRKunz et al. Presented a measurement result that a polysiloxane polymer has a wavelength of 193 nm or less, particularly excellent transparency at 157 nm, and this polymer has a wavelength of 193 nm or less. It is reported that it is suitable for a resist material in the lithography process to be used (see Non-Patent Document 1). It is also known that polysiloxane polymers are excellent in dry etching resistance, and among them, a resist containing polyorganopolysilsesquioxane having a ladder structure has high plasma resistance.

J. Photopolym. Sci. Technol., Vol.12, No.4, 1999

On the other hand, some resist materials using siloxane polymers have already been reported. That is, Patent Document 1 uses a polysiloxane having an acid dissociable group in the side chain in which an acid dissociable group such as a carboxylic acid ester group or a phenol ether group is bonded to a silicon atom via one or more carbon atoms. Patent Document 2 discloses a radiation-sensitive resin composition, and a positive resist using a polymer in which a carboxyl group of poly (2-carboxyethylsiloxane) is protected with an acid-dissociable group such as a t-butyl group is further patented. Document 3 discloses resist resin compositions using polyorganosilsesquioxanes having acid dissociable ester groups.
However, the conventional resist material using a siloxane polymer was not satisfactory particularly in terms of resolution.

Japanese Patent Laid-Open No. 5-323611 JP-A-8-160623 Japanese Patent Laid-Open No. 11-60733

  An object of the present invention is to provide a radiation-sensitive resin composition suitable for use as a chemically amplified resist having an acid dissociable group-containing polysiloxane as a resin component and particularly excellent in resolution.

The present invention includes (A) an acid dissociable group-containing polysiloxane , and (B) a compound (B1) that generates an acid represented by the following formula (I) by irradiation with radiation, and the following formula by irradiation with radiation: A radiation-sensitive acid generator comprising, as an essential component, an acid represented by (II), an acid represented by the following formula (III), or a compound (B2) that generates an acid represented by the following formula (IV): It consists of a radiation sensitive resin composition characterized by containing.

[In the formula (I), each Rf independently represents a fluorine atom or a trifluoromethyl group, and Ra represents a cyclic monovalent hydrocarbon group having 3 to 20 carbon atoms or a cyclic 1 group having 3 to 20 carbon atoms. A cyclic monovalent hydrocarbon group and the cyclic monovalent fluorinated hydrocarbon group may be substituted. ]

[In the formula (II), Rf represents a fluorine atom or a trifluoromethyl group, Rf ′ represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, and Rb represents a hydrogen atom, a straight chain having 1 to 20 carbon atoms. A linear or branched alkyl group, a cyclic monovalent hydrocarbon group having 3 to 20 carbon atoms, or a cyclic monovalent fluorinated hydrocarbon group having 3 to 20 carbon atoms, The hydrogen group and the cyclic monovalent fluorinated hydrocarbon group may be substituted.

In the formula (III), Rs represents a linear or branched alkyl group having 1 to 20 carbon atoms or a cyclic monovalent hydrocarbon group having 3 to 20 carbon atoms, and the cyclic monovalent hydrocarbon group May be substituted.

In the formula (IV), Rc is a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched fluorinated alkyl group having 1 to 20 carbon atoms, or a cyclic group having 3 to 20 carbon atoms. A monovalent hydrocarbon group or a cyclic monovalent fluorinated hydrocarbon group having 3 to 20 carbon atoms, wherein the cyclic monovalent hydrocarbon group and the cyclic monovalent fluorinated hydrocarbon group are substituted; It may be. ]

Hereinafter, the present invention will be described in detail.
(A) Acid-dissociable group-containing polysiloxane As the acid-dissociable group-containing polysiloxane in the present invention, more specifically, alkali-insoluble or alkali-insoluble, which becomes alkali-soluble when the acid-dissociable group is dissociated. there may be mentioned acid-dissociable group-containing polysiloxane represented by the following formula (1) structural unit represented by (hereinafter, "structural unit (1)" hereinafter.) polymer (hereinafter having at least one kind of "polysiloxane (Α) ”) is preferred.

In [the formula (1), A ¹ represents a monovalent organic group having an acid-dissociable group dissociates by acid. ]

In the formula (1), the monovalent organic group having an acid-dissociable group that dissociates with an acid of A ¹ is preferably one or more that dissociates with an acid to generate a carboxyl group, a phenolic hydroxyl group, or an alcoholic hydroxyl group. A polysiloxane such as a linear or branched hydrocarbon group having 1 to 20 carbon atoms having an acid dissociable group and a cyclic monovalent hydrocarbon group having 4 to 30 carbon atoms having the acid dissociable group Mention may be made of groups which are stable under the reaction conditions for producing (α).

The acid dissociable group is preferably a group represented by the following formula (3).

[In Formula (3), P is a single bond, a methylene group, a difluoromethylene group, an optionally substituted linear or branched alkylene group having 2 to 20 carbon atoms, and an optionally substituted carbon number 6 -20 represents a divalent aromatic group or a divalent alicyclic group having 3 to 20 carbon atoms which may be substituted, Q represents -COO- or -O-,
R ² represents a monovalent organic group that is dissociated by an acid to generate a hydrogen atom. ]

  In the formula (3), examples of the linear or branched alkylene group having 2 to 20 carbon atoms of P include an ethylene group, a propylene group, a trimethylene group, a tetramethylene group, and the like. Examples of the divalent aromatic group having 20 to 20 include a phenylene group and a naphthylene group. Examples of the divalent alicyclic group having 3 to 20 carbon atoms include a cyclopropylene group and a cyclobutylene group. And divalent hydrocarbon groups having a bridged alicyclic skeleton such as a norbornane skeleton, a tricyclodecane skeleton, a tetracyclodecane skeleton, and an adamantane skeleton.

Moreover, as a substituent of these alkylene groups, a bivalent aromatic group, and a bivalent alicyclic group, a fluorine atom and a C1-C10 linear or branched fluorinated alkyl group are preferable.
The divalent aromatic group and divalent alicyclic group are a methylene group, a difluoromethylene group, a linear or branched alkylene group having 1 to 10 carbon atoms, or a linear chain having 1 to 10 carbon atoms. Or a branched fluorinated alkylene group.

  Preferred P in formula (3) is a single bond, a methylene group, a difluoromethylene group, a divalent hydrocarbon group having a tricyclodecane skeleton or a fluorinated product thereof, a divalent hydrocarbon group having an adamantane skeleton or a fluorine thereof. And a divalent hydrocarbon group having a norbornane skeleton and a fluorinated product thereof. In particular, a divalent hydrocarbon group having a norbornane skeleton and a fluorinated product thereof are preferable.

Examples of the monovalent organic group that generates a hydrogen atom by dissociating with an acid of R ² include, for example,
Methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, cyclopentyl group, 1-methylcyclopentyl group, 1-ethylcyclopentyl group A linear, branched or cyclic alkyl group such as cyclohexyl group, 1-methylcyclohexyl group, 1-ethylcyclohexyl group, 4-t-butylcyclohexyl group, cycloheptyl group, cyclooctyl group;
Alkyl-substituted adamantyl groups such as 1-methyladamantyl group and 1-ethyladamantyl group;
Aralkyl groups such as a benzyl group, 4-t-butylbenzyl group, phenethyl group, 4-t-butylphenethyl group;
t-butoxycarbonyl group, methoxycarbonyl group, ethoxycarbonyl group, i-propoxycarbonyl group, 2- (trimethylsilyl) ethylcarbonyl group, i-butylcarbonyl group, vinylcarbonyl group, allylcarbonyl group, benzylcarbonyl group, 4-ethoxy An organic carbonyl group such as a -1-naphthylcarbonyl group;

Methoxymethyl group, methylthiomethyl group, ethoxymethyl group, t-butoxymethyl group, (phenyldimethylsilyl) methoxymethyl group, benzyloxymethyl group, t-butoxymethyl group, siloxymethyl group, 2-methoxyethoxymethyl group, 2 , 2,2-trichloroethoxymethyl group, bis (2-chloroethoxy) methyl group, 1-methoxycyclohexyl group, tetrahydropyranyl group, 4-methoxytetrahydropyranyl group, tetrahydrofuranyl group, 1-methoxyethyl group, 1 -Ethoxyethyl group, 1- (2-chloroethoxy) ethyl group, 1-methyl-1-methoxyethyl group, 1-methyl-1-benzyloxyethyl group, 1- (2-chloroethoxy) ethyl group, 1- Oxygen sources in formula (3), such as methyl-1-benzyloxy-2-fluoroethyl group The organic group that forms a bond to acetal structure;
Examples include silyl groups such as trimethylsilyl group, triethylsilyl group, dimethylethylsilyl group, t-butyldimethylsilyl group, t-butyldiphenylsilyl group, triphenylsilyl group, diphenylmethylsilyl group, and t-butylmethoxyphenylsilyl group. be able to.

  Among the monovalent organic groups that dissociate by these acids and generate hydrogen atoms, t-butyl, tetrahydropyranyl, tetrahydrofuranyl, methoxymethyl, ethoxymethyl, 1-methoxyethyl, 1-ethoxy An ethyl group, t-butyldimethylsilyl group and the like are preferable.

In the formula (2), examples of the linear, branched or cyclic alkyl group having 1 to 10 carbon atoms represented by R ¹ include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, cyclopentyl. Group, cyclohexyl group and the like. Examples of the linear, branched or cyclic halogenated alkyl group having 1 to 10 carbon atoms include trifluoromethyl group, pentafluoroethyl group, heptafluoro-n- A propyl group, a heptafluoro-i-propyl group, a perfluorocyclohexyl group, etc. can be mentioned.
R ¹ in Formula (2) is preferably a methyl group, an ethyl group, a trifluoromethyl group, a pentafluoroethyl group, or the like.

Polysiloxane ((alpha)) can also have 1 or more types of the other structural unit which does not have an acid dissociable group.
Examples of such other structural units include a structural unit represented by the following formula (4) (hereinafter referred to as “structural unit (4)”) and a structural unit represented by the following formula (5) (hereinafter referred to as “ Structural unit (5) ”), etc.

[In the formulas (4) and (5), each R ³ is independently of the formula -PH, -PF or -PQH (wherein each P is independently of the formula ( 3), Q is as defined in formula (3).) Represents a monovalent group represented by formula (1), and R ¹ is a straight-chain, branched or A cyclic alkyl group or a linear, branched or cyclic halogenated alkyl group having 1 to 10 carbon atoms is shown . ]

In formula (4) and formula (5), preferred specific examples of R ³ include groups represented by the following formulas (6) to (11), a methyl group, an ethyl group, a norbornyl group, and a tetracyclodecanyl group. Etc.

[In the formula (6), each R ⁴ is independently a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an acid. 1 represents a monovalent organic group having an acid-dissociable group that dissociates by each, and each R ⁵ is independently a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, or a carbon atom. 1 represents an alkyl group having 1 to 10, and at least one of ⁵ R ⁴ and 2i R ⁵ is a fluorine atom or a fluorinated alkyl group having 1 to 10 carbon atoms, and i is an integer of 0 to 10 is there. ]

[In the formula (7), each R ⁴ independently represents a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an acid. 1 represents a monovalent organic group having an acid-dissociable group that dissociates by each, and each R ⁵ is independently a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, or a carbon atom. Represents an alkyl group having a number of 1 to 10, and at least one of 7 R ⁴ and 2i R ⁵ is a fluorine atom or a fluorinated alkyl group having 1 to 10 carbon atoms, and i is an integer of 0 to 10 is there. ]

[In the formula (8), each R ⁴ is independently a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an acid. 1 represents a monovalent organic group having an acid-dissociable group that dissociates by each, and each R ⁵ is independently a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, or a carbon atom. Represents an alkyl group having a number of 1 to 10, and at least one of 7 R ⁴ and 2i R ⁵ is a fluorine atom or a fluorinated alkyl group having 1 to 10 carbon atoms, and i is an integer of 0 to 10 is there. ]

[In the formula (9), each R ⁴ independently represents a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an acid. 1 represents a monovalent organic group having an acid-dissociable group that dissociates by each, and each R ⁵ is independently a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom, or a carbon atom. 1 represents an alkyl group having 1 to 10, and at least one of (3 + 2j) R ⁴ and 2i R ⁵ is a fluorine atom or a fluorinated alkyl group having 1 to 10 carbon atoms, and i is 0 to 10 It is an integer, j is an integer of 1-18. ]

[In the formula (10), one of (12 + 6k) R ^{6 s} represents a group — [C (R ⁵ ) ₂ ] _i —, and the remaining R ^6s are each independently a fluorine atom and a carbon number of 1 10 fluorinated alkyl group, a hydrogen atom, a halogen atom other than a fluorine atom, a monovalent organic group having an acid-dissociable group dissociates by an alkyl group or an acid, of 1 to 10 carbon atoms, each R ⁵ is Each independently represents a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom or an alkyl group having 1 to 10 carbon atoms, and (11 + 6k) remaining R ⁶ and At least one of 2i R < ⁵ > is a fluorine atom or a C1-C10 fluorinated alkyl group, i is an integer of 0-10, and k is an integer of 0-3. ]

[In the formula (11), one of the 16 R ⁶ groups represents a group — [C (R ⁵ ) ₂ ] _i —, and the remaining R ⁶ groups are each independently a fluorine atom, having 1 to 10 carbon atoms. A monovalent organic group having a hydrogen atom, a halogen atom other than a fluorine atom, an alkyl group having 1 to 10 carbon atoms, or an acid-dissociable group that dissociates with an acid, and each R ⁵ is mutually Independently represents a fluorine atom, a fluorinated alkyl group having 1 to 10 carbon atoms, a hydrogen atom, a halogen atom other than a fluorine atom or an alkyl group having 1 to 10 carbon atoms, and 15 remaining R ⁶ and 2i R ^At least one of ⁵ is a fluorine atom or a fluorinated alkyl group having 1 to 10 carbon atoms. ]

The polysiloxane (α) is, for example, from a linear or cyclic oligomer in which a compound represented by the following formula (12) (hereinafter referred to as “silane compound (12)”) and a silane compound (12) are partially condensed. At least one member of the group can be produced by a process comprising a step of polycondensation in the presence of an acidic catalyst or a basic catalyst, preferably in the presence of an acidic catalyst.

[In Formula (12), A ¹ is as defined in Formula (1), and each R ⁷ independently represents a monovalent saturated hydrocarbon group having 1 to 10 carbon atoms. ]

R ⁷ in Formula (12) is preferably an alkyl group having 1 to 10 carbon atoms, and particularly preferably a methyl group or an ethyl group.

The “linear or cyclic oligomer in which the silane compound (12) is partially condensed” as used herein is a linear oligomer that is condensed between two R ⁷ O—Si groups in the silane compound (12). In the case of, usually 2-10 mer, preferably 2-5 mer is formed, and in the case of cyclic oligomer, it usually means 3-10 mer, preferably 3-5 mer oligomer. .

A silane compound (12) can be used individually or in mixture of 2 or more types.
Moreover, in this invention, 1 or more types of other silane compounds can be used together with a silane compound (12) or its partial condensate.
Examples of the other silane compound include a silane compound represented by the following formula (14) (hereinafter referred to as “silane compound (14)”) and a silane compound represented by the following formula (15) (hereinafter referred to as “ Silane compound (15) ") and partial condensates of these silane compounds.
The “partial condensate” here is a linear oligomer in which each silane compound usually forms a 2 to 10 mer, preferably a 2 to 5 mer, or usually a 3 to 10 mer, Preferably, it means a cyclic oligomer forming a 3-5 mer.

[In Formula (14) and Formula (15), R ¹ is as defined in Formula ( 5 ), R ³ is as defined in Formula (4) and Formula (5), and each R ⁷ is a formula As defined in (12). ]

R ⁷ in Formula (14) and Formula (15) is preferably an alkyl group having 1 to 10 carbon atoms, and particularly preferably a methyl group or an ethyl group.

In the present invention, at least one of the silane compound (14) and the silane compound (15) or a partial condensate thereof, preferably the silane compound (14) or a partial condensate thereof, is converted into the silane compound (12) or the condensate thereof. By co-condensing with the partial condensate, the molecular weight and glass transition temperature (Tg) of the resulting polysiloxane (α) can be controlled, and the transparency at wavelengths of 193 nm or less, particularly 193 nm and 157 nm can be further improved. .
The total use ratio of the silane compound (14), the silane compound (15) or a partial condensate thereof is usually 1 mol% or more, preferably 5 to 95 mol%, more preferably 10 to 10 mol% based on the total silane compounds. 90 mol%. In this case, when the total use ratio is less than 1 mol%, the effect of improving transparency particularly at wavelengths of 193 nm and 157 nm tends to decrease.

Among the acidic catalysts used for the production of polysiloxane (α), examples of inorganic acids include hydrochloric acid, sulfuric acid, nitric acid, boric acid, phosphoric acid, titanium tetrachloride, zinc chloride, and aluminum chloride. Examples of organic acids include formic acid, acetic acid, n-propionic acid, butyric acid, valeric acid, oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, adipic acid, phthalic acid, terephthalic acid, acetic anhydride, anhydrous Mention may be made of maleic acid, citric acid, benzenesulfonic acid, p-toluenesulfonic acid, methanesulfonic acid and the like.
Of these acidic catalysts, hydrochloric acid, sulfuric acid, acetic acid, oxalic acid, malonic acid, maleic acid, fumaric acid, acetic anhydride, maleic anhydride and the like are preferable.
The acidic catalyst can be used alone or in admixture of two or more.
The usage-amount of an acidic catalyst is 0.01-10,000 weight part normally with respect to 100 weight part of whole quantity of a silane compound, Preferably it is 0.1-100 weight part.

  Among the basic catalysts used for the production of polysiloxane (α), examples of inorganic bases include lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, sodium hydrogen carbonate, and carbonic acid. Examples thereof include potassium hydrogen, sodium carbonate, potassium carbonate and the like.

Moreover, as organic bases, for example,
linear, branched or cyclic monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, cyclohexylamine;
Di-n-butylamine, di-n-pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine, cyclohexylmethylamine, Linear, branched or cyclic dialkylamines such as dicyclohexylamine;
Triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri -Linear, branched or cyclic trialkylamines such as n-decylamine, cyclohexyldimethylamine, dicyclohexylmethylamine, tricyclohexylamine;

Aromatic amines such as aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, naphthylamine;
Ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4, 4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2- (4-aminophenyl) -2- ( 3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1, Aromatic diamines such as 3-bis [1- (4-aminophenyl) -1-methylethyl] benzene;

Imidazoles such as imidazole, benzimidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole;
Pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, Pyridines such as quinoline, 4-hydroxyquinoline, 8-oxyquinoline, acridine; piperazines such as piperazine, 1- (2-hydroxyethyl) piperazine,
Other nitrogen-containing heterocyclic compounds such as pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, morpholine, 4-methylmorpholine, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2.2] octane Etc.

Of these basic catalysts, triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine and the like are preferable.
The basic catalysts can be used alone or in admixture of two or more. The usage-amount of a basic catalyst is 0.01-10,000 weight part normally with respect to 100 weight part of whole quantity of a silane compound, Preferably it is 0.1-1,000 weight part.

  In the polycondensation reaction for producing the polysiloxane (α), it is preferable that the silane compound is polycondensed in the presence of an acidic catalyst, and then the basic catalyst is added to further proceed the reaction. By carrying out such a reaction, even when a silane compound having an acid-dissociable group that is unstable under acidic conditions is used, a crosslinking reaction can occur, and the molecular weight and glass transition temperature (Tg) are high. It becomes possible to obtain polysiloxane (α) exhibiting good characteristics. Moreover, the solubility with respect to the developing solution of the obtained polysiloxane ((alpha)) can also be adjusted by controlling the reaction degree on basic conditions and controlling a crosslinking degree.

  The polycondensation reaction under the acidic condition and the basic condition is preferably performed in an atmosphere of an inert gas such as nitrogen or argon, which makes it difficult for the pattern forming layer to be negative during pattern formation.

The polycondensation reaction can be carried out in the absence of a solvent or in a solvent.
As the solvent, for example,
2-butanone, 2-pentanone, 3-methyl-2-butanone, 2-hexanone, 4-methyl-2-pentanone, 3-methyl-2-pentanone, 3,3-dimethyl-2-butanone, 2-heptanone, Linear or branched ketones such as 2-octanone;
Cyclic ketones such as cyclopentanone, 3-methylcyclopentanone, cyclohexanone, 2-methylcyclohexanone, 2,6-dimethylcyclohexanone, isophorone;
Propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-i-propyl ether acetate, propylene glycol mono-n-butyl ether acetate, propylene glycol mono-i-butyl ether acetate Propylene glycol monoalkyl ether acetates such as propylene glycol mono-sec-butyl ether acetate, propylene glycol mono-t-butyl ether acetate;
Methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate,
N-propyl 2-hydroxypropionate, i-propyl 2-hydroxypropionate, n-butyl 2-hydroxypropionate, i-butyl 2-hydroxypropionate, sec-butyl 2-hydroxypropionate, 2-hydroxypropionic acid alkyl 2-hydroxypropionates such as t-butyl;
Methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-
Alkyl 3-alkoxypropionates such as methyl ethoxypropionate and ethyl 3-ethoxypropionate;

n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclohexanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether Alcohols such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether;
Dialkylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether;
Ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate;

Aromatic hydrocarbons such as toluene and xylene;
Ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3 -Methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate, etc. In addition to esters,
N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, benzyl ethyl ether, di-n-hexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, caproic acid, caprylic acid, 1-octanol, 1 -Nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate and the like.
These solvents can be used alone or in admixture of two or more.
The amount of the solvent used is usually 2,000 parts by weight or less with respect to 100 parts by weight of the total amount of the silane compound.

  The polycondensation reaction is carried out in the absence of a solvent, or 2-butanone, 2-pentanone, 3-methyl-2-butanone, 2-hexanone, 4-methyl-2-pentanone, 3-methyl-2-pentanone, 3, 3 -Dimethyl-2-butanone, 2-heptanone, 2-octanone, cyclopentanone, 3-methylcyclopentanone, cyclohexanone, 2-methylcyclohexanone, 2,6-dimethylcyclohexanone, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di- n-propyl ether, diethylene glycol di-n-butyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate It is preferably carried out in a solvent bets like.

In the polycondensation reaction, water can be added to the reaction system. In this case, the amount of water added is usually 10,000 parts by weight or less with respect to 100 parts by weight of the total amount of the silane compound.
Furthermore, in the polycondensation reaction, hexamethyldisiloxane can be added to control the molecular weight of the resulting polysiloxane (α) and improve the stability. The amount of hexamethyldisiloxane added is usually 500 parts by weight or less, preferably 50 parts by weight or less, based on 100 parts by weight of the total amount of silane compounds. In this case, if the amount of hexamethyldisiloxane added exceeds 500 parts by weight, the molecular weight of the resulting polymer tends to be small, and the glass transition temperature (Tg) tends to decrease.
The reaction temperature in the polycondensation is usually −50 to 300 ° C., preferably 20 to 100 ° C., and the reaction time is usually about 1 minute to 100 hours.

In the polysiloxane (α), the content of the structural unit (1) is preferably from 1 to 95 mol%, more preferably from 5 to 80 mol%, particularly preferably from 10 to 60 mol%, based on all structural units. is there. In this case, if the content of the structural unit (1) is less than 1 mol%, the resolution at the time of pattern formation may be lowered, and if it exceeds 95 mol%, the transparency of the resulting polymer to radiation tends to be lowered. There is.

Further, the total content of the structural unit (4) and the structural unit (5) optionally contained in the polysiloxane (α) is preferably 5 to 95 mol%, more preferably, with respect to all the structural units. It is 20-95 mol%, Most preferably, it is 40-90 mol%. In this case, if the total content is less than 5 mol%, the transparency of the resulting polymer to radiation may be lowered, while if it exceeds 95 mol%, the resolution during pattern formation may be lowered.
The polysiloxane (α) preferably has a partially ladder structure. This ladder structure is basically introduced by the structural unit (1) or the structural unit (4).

The polystyrene-reduced weight average molecular weight (hereinafter referred to as “Mw”) of the acid-dissociable group-containing polysiloxane by gel permeation chromatography (GPC) is usually 500 to 100,000, preferably 500 to 50,000, particularly preferably. Is 1,000 to 10,000. In this case, if the Mw of the acid-dissociable group-containing polysiloxane is less than 500, the glass transition temperature (Tg) of the resulting polymer tends to decrease, whereas if it exceeds 100,000, the resulting polymer dissolves in the solvent. Tend to decrease.
Further, the ratio (Mw / Mn) of Mw of the acid-dissociable group-containing polysiloxane and the polystyrene-equivalent number average molecular weight (hereinafter referred to as “Mn”) by gel permeation chromatography (GPC) is 2.5 or less, preferably Is 2 or less, more preferably 1.8 or less.
Moreover, the glass transition temperature (Tg) of acid dissociable group containing polysiloxane is 0-500 degreeC normally, Preferably it is 50-250 degreeC. In this case, if the glass transition temperature (Tg) of the acid-dissociable group-containing polysiloxane is less than 0 ° C, pattern formation may be difficult. If the glass transition temperature exceeds 500 ° C, the solubility of the resulting polymer in a solvent is likely to occur. Tends to decrease.
In this invention, acid dissociable group containing polysiloxane can be used individually or in mixture of 2 or more types.

(B) Radiation-sensitive acid generator The radiation-sensitive acid generator in the present invention (hereinafter referred to as “acid generator (B)”) is irradiated with radiation such as far ultraviolet rays, electron beams, and X-rays (hereinafter, referred to as “acid generator (B)”). by.) referred to as "exposure", the formula (I) represented by acid (hereinafter "acid (I)" hereinafter.) a compound which generates an (hereinafter "acid generator (B1)" hereinafter. a) The acid generator (B2) described below is an essential component.
Examples of the acid generator (B1) and the acid generator (B2) include onium salt compounds, sulfone compounds, sulfonic acid compounds, carboxylic acid compounds, diazoketone compounds, and halogen-containing compounds.

(B2) Upon exposure, an acid represented by the following formula (II) (hereinafter referred to as “acid (II)”) and an acid represented by the following formula (III) (hereinafter referred to as “acid (III)”). ) Or an acid represented by the following formula (IV) (hereinafter referred to as “acid (IV)”) (hereinafter referred to as “acid generator (B2)”).

[In the formula (II), Rf represents a fluorine atom or a trifluoromethyl group,
Rf ′ represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group,
Rb is a hydrogen atom, a linear or branched alkyl group having 1 to 20 carbon atoms, a cyclic monovalent hydrocarbon group having 3 to 20 carbon atoms, or a cyclic monovalent fluorinated carbon atom having 3 to 20 carbon atoms. Represents a hydrogen group, and the cyclic monovalent hydrocarbon group and the cyclic monovalent fluorinated hydrocarbon group may be substituted.

In the formula (III), Rs represents a linear or branched alkyl group having 1 to 20 carbon atoms or a cyclic monovalent hydrocarbon group having 3 to 20 carbon atoms, and the cyclic monovalent hydrocarbon group May be substituted.

In the formula (IV), Rc is a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched fluorinated alkyl group having 1 to 20 carbon atoms, or a cyclic group having 3 to 20 carbon atoms. A monovalent hydrocarbon group or a cyclic monovalent fluorinated hydrocarbon group having 3 to 20 carbon atoms, wherein the cyclic monovalent hydrocarbon group and the cyclic monovalent fluorinated hydrocarbon group are substituted; It may be. ]

  In the formula (II), formula (III) and formula (IV), specific examples of the linear or branched alkyl group having 1 to 20 carbon atoms of Rb, Rs and Rc include a methyl group, an ethyl group, n -Propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, etc. be able to.

Specific examples of the linear or branched fluorinated alkyl group having 1 to 20 carbon atoms of Rc in the formula (IV) include trifluoromethyl group, pentafluoroethyl group, heptafluoro-n-propyl group, hepta Fluoro-i-propyl group, nonafluoro-n-butyl group, nonafluoro-i-butyl group, nonafluoro-sec-butyl group, nonafluoro-t-butyl group, perfluoro-n-pentyl group, perfluoro-n-hexyl group Perfluoro-n-heptyl group, perfluoro-n-octyl group, and the like.

In formula (I), formula (II), formula (III) and formula (IV), Ra, Rb, Rs and Rc each having 3 to 20 carbon atoms or a cyclic monovalent hydrocarbon group having 3 to 20 carbon atoms Examples of the cyclic monovalent fluorinated hydrocarbon group or substituted derivatives thereof include groups represented by the following formulas (16) to (22).

[In the formulas (16) to (22), each R ⁸ is independently a hydrogen atom, halogen atom, hydroxyl group, acetyl group, carboxyl group, nitro group, cyano group, primary amino group, secondary amino group, carbon A linear or branched alkoxyl group having 1 to 10 carbon atoms, a linear or branched alkyl group having 1 to 10 carbon atoms, or a linear or branched fluorinated alkyl group having 1 to 10 carbon atoms Each R ⁹ independently represents a hydrogen atom, a halogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a linear or branched fluorinated alkyl group having 1 to 10 carbon atoms, m Is an integer from 0 to 10.
In Formula (19), n is an integer of 1-18.
In Formula (20), p is an integer of 0-3. ]

Preferred acids (I) in the present invention include, for example,
In the bond of the group represented by the formulas (16) to (22), —CF ₂ CF ₂ SO ₃ H,
_{-CF 2 CF (CF 3) SO} 3 H, -CF (CF 3) CF 2 SO 3 H,
An acid having a group of —CF (CF ₃ ) CF (CF ₃ ) SO ₃ H, —C (CF ₃ ) ₂ CF ₂ SO ₃ H or —CF ₂ C (CF ₃ ) ₂ SO ₃ H bonded, for example, Examples thereof include acids of formulas (I-1) to (I-10).

In addition, as a preferable acid (II) in the present invention, for example,
1-fluoroethanesulfonic acid, 1-fluoro-n-propanesulfonic acid, 1-fluoro-n-butanesulfonic acid, 1-fluoro-n-octanesulfonic acid, 1,1-difluoroethanesulfonic acid, 1,1-difluoro -N-propanesulfonic acid, 1,1-difluoro-n-butanesulfonic acid, 1,1-difluoro-n-octanesulfonic acid, 1-trifluoromethyl-n-propanesulfonic acid, 1-trifluoromethyl-n -Butanesulfonic acid, 1-trifluoromethyl-n-octanesulfonic acid, 1,1-bis (trifluoromethyl) ethanesulfonic acid, 1,1-bis (trifluoromethyl) -n-propanesulfonic acid, 1, 1-bis (trifluoromethyl) -n-butanesulfonic acid, 1,1-bis (trifluoromethyl) -n-octa Or a sulfonic acid,

In the bond of the group represented by the formulas (16) to (22), —CF ₂ SO ₃ H,
Acids to which groups of —CHFSO ₃ H, —CH (CF ₃ ) SO ₃ H or —C (CF ₃ ) ₂ SO ₃ H are bonded, such as acids of the following formulas (II-1) to (II-40), etc. Can be mentioned.

Moreover, as a preferable acid (III) in the present invention, for example,
Methanesulfonic acid, ethanesulfonic acid, n-propanesulfonic acid, n-butanesulfonic acid, i-butanesulfonic acid, sec-butanesulfonic acid, t-butanesulfonic acid, n-pentanesulfonic acid, n-hexanesulfonic acid, linear, branched or cyclic alkylsulfonic acids such as n-octanesulfonic acid, cyclopentanesulfonic acid and cyclohexanesulfonic acid;
Aromatic sulfonic acids such as benzenesulfonic acid, p-toluenesulfonic acid, benzylsulfonic acid, α-naphthalenesulfonic acid, β-naphthalenesulfonic acid;
10-camphorsulfonic acid,
The bond group represented by the formula (16) to (22), can be exemplified acids such as -SO ₃ H group is bonded.

Furthermore, preferred acids (IV) in the present invention include, for example,
Acetic acid, n-propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, caproic acid, benzoic acid, salicylic acid, phthalic acid, terephthalic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, cyclobutanecarboxylic acid, cyclo Pentanecarboxylic acid, cyclohexanecarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2-norbornanecarboxylic acid, 2,3-norbornanedicarboxylic acid, norbornyl-2 -Acetic acid, 1-adamantane Carboxylic acid, 1-adamantaneacetic acid, 1,3-adamantane dicarboxylic acid, 1,3-adamantane diacetic acid, lithocholic acid, deoxycholic acid, chenodeoxycholic acid, cholic acid,
Examples of the bond of the groups represented by the formulas (16) to (22) include an acid having a —COOH group bonded thereto.

Examples of onium salt compounds that generate acid (I), acid (II), acid (III), or acid (IV) include:
Diphenyliodonium salt, bis (4-t-butylphenyl) iodonium salt, triphenylsulfonium salt,
4-hydroxyphenyl, phenyl, methylsulfonium salt, cyclohexyl, 2-oxocyclohexyl, methylsulfonium salt, dicyclohexyl, 2-oxocyclohexylsulfonium salt, 2-oxocyclohexyldimethylsulfonium salt, 4-hydroxyphenyl, benzyl, methylsulfonium salt,
1-naphthyldimethylsulfonium salt, 1-naphthyldiethylsulfonium salt, 1- (4-cyanonaphthyl) dimethylsulfonium salt, 1- (4-cyanonaphthyl) diethylsulfonium salt, 1- (4-nitronaphthyl) dimethylsulfonium salt, 1- (4-nitronaphthyl) diethylsulfonium salt, 1- (4-methylnaphthyl) dimethylsulfonium salt, 1- (4-methylnaphthyl) diethylsulfonium salt, 1- (4-hydroxynaphthyl) dimethylsulfonium salt, 1- (4-hydroxynaphthyl) diethylsulfonium salt,

1- [1- (4-hydroxynaphthyl)] tetrahydrothiophenium salt, 1- [1- (4-ethoxynaphthyl)] tetrahydrothiophenium salt, 1- [1- (4-n-butoxynaphthyl)] Tetrahydrothiophenium salt, 1- [1- (4-methoxymethoxynaphthyl)] tetrahydrothiophenium salt, 1- [1- (4-ethoxymethoxynaphthyl)] tetrahydrothiophenium salt, 1- [1- {4- (1-methoxyethoxy) naphthyl}] tetrahydrothiophenium salt, 1- [1- {4- (2-methoxyethoxy) naphthyl}] tetrahydrothiophenium salt, 1- [1- (4-methoxy Carbonyloxynaphthyl)] tetrahydrothiophenium salt, 1- [1- (4-ethoxycarbonyloxynaphthyl)] tetrahydrothio Henium salt, 1- [1- (4-n-propoxycarbonyloxynaphthyl)] tetrahydrothiophenium salt, 1- [1- (4-i-propoxycarbonyloxynaphthyl)] tetrahydrothiophenium salt, 1- [ 1- (4-n-butoxycarbonyloxynaphthyl)] tetrahydrothiophenium salt, 1- [1- (4-t-butoxycarbonyloxynaphthyl)] tetrahydrothiophenium salt, 1- [1- {4- ( 2-tetrahydrofuranyloxy) naphthyl}] tetrahydrothiophenium salt, 1- [1- {4- (2-tetrahydropyranyloxy) naphthyl}] tetrahydrothiophenium salt, 1- [1- (4-benzyloxy) Naphthyl)] tetrahydrothiophenium salt, 1- [1- (1-naphthylacetomethyl)] tetrahi Rochiofeniumu salts and the like can be mentioned.

Examples of the sulfone compound that generates acid (I), acid (II), or acid (III) include β-ketosulfone, β-sulfonylsulfone, and α-diazo compounds of these compounds. .
Examples of the sulfonic acid compound that generates acid (I), acid (II), or acid (III) include sulfonic acid esters, sulfonic acid imides, aryl sulfonic acid esters, and imino sulfonates.
Examples of carboxylic acid compounds that generate acid (IV) include carboxylic acid esters, carboxylic acid imides, and carboxylic acid cyanates.
Examples of the diazo ketone compound that generates acid (I), acid (II), acid (III), or acid (IV) include 1,3-diketo-2-diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds, and the like. Can be mentioned.
Furthermore, examples of the halogen-containing compound that generates acid (I), acid (II), acid (III), or acid (IV) include haloalkyl group-containing hydrocarbon compounds, haloalkyl group-containing heterocyclic compounds, and the like. Can do.

In this invention, the usage-amount of an acid generator (B) is 0.1 to 10 weight normally with respect to 100 weight part of (A) acid dissociable group containing polysiloxane from a viewpoint of ensuring a sensitivity and developability. Parts, preferably 0.5 to 7 parts by weight. In this case, if the amount of the acid generator (B) used is less than 0.1 parts by weight, the sensitivity and developability tend to decrease. The shape may be damaged.
Moreover, the use ratio of the acid generator (B1) with respect to the entire acid generator (B) is particularly preferably 30 to 90% by weight.
In this invention, an acid generator (B1) can be used individually or in mixture of 2 or more types, and an acid generator (B2) can be used individually or in mixture of 2 or more types. Can do.

Various Additives Various additives such as an acid diffusion control agent, a dissolution control agent, and a surfactant can be blended in the radiation sensitive resin composition of the present invention.
The acid diffusion control agent is a component having an action of controlling an undesired chemical reaction in a non-exposed region by controlling a diffusion phenomenon in the resist film of an acid generated from the acid generator (B) by exposure.
By blending such an acid diffusion control agent, the storage stability of the resulting composition is further improved, the resolution as a resist is further improved, and the holding time (PED) from exposure to development processing is improved. A change in the line width of the resist pattern due to fluctuations can be suppressed, and a composition having excellent process stability can be obtained. As the acid diffusion controller, a nitrogen-containing organic compound whose basicity is not changed by exposure or heat treatment in the resist pattern forming step is preferable.
As such a nitrogen-containing organic compound, for example, the following formula (23)

[In the formula (23), each R ¹⁰ independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group. ]

(Hereinafter referred to as “nitrogen-containing compound (i)”), a compound having two nitrogen atoms in the same molecule (hereinafter referred to as “nitrogen-containing compound (b)”), 3 nitrogen atoms. A polymer having at least one (hereinafter referred to as “nitrogen-containing compound (c)”), an amide group-containing compound, a urea compound, a nitrogen-containing heterocyclic compound, and the like can be given.

  Examples of the nitrogen-containing compound (i) include mono (cyclo) alkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, cyclohexylamine; di-n- Butylamine, di-n-pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine, cyclohexylmethylamine, dicyclohexylamine, etc. Di (cyclo) alkylamines; triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine , Tri-n-nonylamine, tri-n-decylamine, cyclohexyl Tri (cyclo) alkylamines such as dimethylamine, dicyclohexylmethylamine, and tricyclohexylamine; aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4 -Aromatic amines such as nitroaniline, diphenylamine, triphenylamine and naphthylamine can be mentioned.

Examples of the nitrogen-containing compound (b) include ethylenediamine, N, N, N′N′-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4,4′-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene It can be mentioned.
Examples of the nitrogen-containing compound (c) include polyethyleneimine, polyallylamine, 2-dimethylaminoethylacrylamide polymer, and the like.

Examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone and the like. Can be mentioned.
Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n-butyl. Examples include thiourea. Examples of the nitrogen-containing heterocyclic compound include imidazoles such as imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, and 2-phenylbenzimidazole; pyridine, 2-methylpyridine, 4-methyl Pyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 4-hydroxyquinoline, 8-oxy Pyridines such as quinoline and acridine; piperazines such as piperazine and 1- (2-hydroxyethyl) piperazine, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, morpholine, 4-methylmorpholine, 1,4 Dimethylpiperazine, and 1,4-diazabicyclo [2.2.2] octane.

Of these nitrogen-containing organic compounds, nitrogen-containing compounds (a) and nitrogen-containing heterocyclic compounds are preferable. Among nitrogen-containing compounds (a), tri (cyclo) alkylamines are particularly preferable, Among the ring compounds, imidazoles, pyridines, and piperazines are particularly preferable.
The acid diffusion controller can be used alone or in admixture of two or more.
The compounding amount of the acid diffusion controller is usually 15 parts by weight or less, preferably 10 parts by weight or less, more preferably 5 parts by weight or less with respect to 100 parts by weight of the (A) acid dissociable group-containing polysiloxane. In this case, when the compounding amount of the acid diffusion controller exceeds 15 parts by weight, the sensitivity as a resist and the developability of the exposed part tend to be lowered. If the amount of the acid diffusion controller is less than 0.001 part by weight, the pattern shape and dimensional fidelity as a resist may be lowered depending on the process conditions.

  Examples of the dissolution control agent include compounds represented by the following formula (24) or formula (25).

[In the formula (24) and the formula (25), each R ¹¹ independently represents a hydrogen atom, a t-butyl group, a t-butoxycarbonyl group, a methoxymethyl group, an ethoxymethyl group, a 1-ethoxyethyl group or a tetrahydro group. A pyranyl group is shown. ]

  The blending amount of the dissolution control agent is usually 2 to 30 parts by weight, preferably 5 to 20 parts by weight with respect to 100 parts by weight of the acid dissociable group-containing polysiloxane.

The surfactant is a component that exhibits an effect of improving coatability, developability, and the like.
Examples of such surfactants include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, and polyethylene glycol dilaurate. In addition to nonionic surfactants such as polyethylene glycol distearate, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (manufactured by Kyoeisha Chemical Co., Ltd.), Ftop EF301, EF303, EF352 (manufactured by Tochem Products), Megafax F171, F173 (manufactured by Dainippon Ink and Chemicals), Fluorad FC430, FC431 (manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 ( Asahi Glass Co., Ltd.).
These surfactants can be used alone or in admixture of two or more.
The compounding amount of the surfactant is usually 2 parts by weight or less with respect to 100 parts by weight in total of the acid dissociable group-containing polysiloxane and the acid generator (B).
Moreover, an antihalation agent, an adhesion assistant, a storage stabilizer, an antifoaming agent and the like can be blended as additives other than those described above.

The radiation-sensitive resin composition of the present invention is usually prepared as a composition solution by dissolving each component in a solvent and filtering through, for example, a filter having a pore size of about 0.2 μm.
The solvent used in the composition solution is not particularly limited as long as it can dissolve the acid-dissociable group-containing polysiloxane, the acid generator and the additive component.
2-butanone, 2-pentanone, 3-methyl-2-butanone, 2-hexanone, 4-methyl-2-pentanone, 3-methyl-2-pentanone, 3,3-dimethyl-2-butanone, 2-heptanone, Linear or branched ketones such as 2-octanone;
Cyclic ketones such as cyclopentanone, 3-methylcyclopentanone, cyclohexanone, 2-methylcyclohexanone, 2,6-dimethylcyclohexanone, isophorone;
Propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-i-propyl ether acetate, propylene glycol mono-n-butyl ether acetate, propylene glycol mono-i-butyl ether acetate Propylene glycol monoalkyl ether acetates such as propylene glycol mono-sec-butyl ether acetate, propylene glycol mono-t-butyl ether acetate;
Methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, n-propyl 2-hydroxypropionate, i-propyl 2-hydroxypropionate, n-butyl 2-hydroxypropionate, i-butyl 2-hydroxypropionate, Alkyl 2-hydroxypropionates such as sec-butyl 2-hydroxypropionate and t-butyl 2-hydroxypropionate;
In addition to alkyl 3-alkoxypropionates such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate and ethyl 3-ethoxypropionate,

n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclohexanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether , Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, propylene glycol monomethyl ether , Propylene glycol monoethyl Ether, propylene glycol mono-n-propyl ether, toluene, xylene, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl acetoacetate, Ethyl acetoacetate, methyl pyruvate, ethyl pyruvate, N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, benzyl ethyl ether, di-n-hexyl ether, diethylene glycol monomethyl ether, diethylene glycol Cole monoethyl ether, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, etc. Can do.

These solvents can be used alone or in admixture of two or more, but in particular, linear or branched ketones, cyclic ketones, propylene glycol monoalkyl ether acetates, 2- Alkyl hydroxypropionates and alkyl 3-alkoxypropions are preferred.
The amount of the solvent used in the liquid composition of the radiation sensitive resin composition is such that the total solid concentration in the solution is usually 1 to 25% by weight, preferably 2 to 15% by weight.

The radiation sensitive resin composition of the present invention can be suitably used as a chemically amplified resist for forming a resist pattern on a substrate.
Underlayer film When a resist pattern is formed using the radiation-sensitive resin composition of the present invention, an underlayer film is previously formed on the substrate surface in order to suppress the influence of standing waves due to the exposed radiation. You can also.

  The polymer forming the lower layer film (hereinafter referred to as “polymer for lower layer film”) is preferably one that effectively suppresses the influence of standing waves and has sufficient dry etching resistance. Is preferably 85% by weight or more, more preferably 90% by weight, and a polymer having an aromatic hydrocarbon structure in the molecule (hereinafter referred to as “polymer for lower layer film (β)”) is desirable.

  Examples of the polymer for the lower layer film (β) include a polymer having a structural unit represented by the following formula (26) (hereinafter referred to as “polymer for lower layer film (β-1)”), and the following formula ( 27) (hereinafter referred to as “polymer for lower layer film (β-2)”), polymer having a structural unit represented by the following formula (28) (hereinafter, “ Underlayer film polymer (β-3) ”), a polymer having a structural unit represented by the following formula (29) (hereinafter referred to as“ underlayer film polymer (β-4) ”), and the like. Can be mentioned.

[In the formulas (26) to (29), each R ¹² independently represents a monovalent atom or a monovalent group, q is an integer of 0 to 4, and R ¹³ is a hydrogen atom or a monovalent group. An organic group is shown. ]

In the formulas (26) to (29), examples of the monovalent atom or group for R ¹² include a halogen atom, a hydroxyl group, a mercapto group, a carboxyl group, a nitro group, a sulfonic acid group, a phenyl group, an alkyl group, and an alkenyl group. Group, amino group, acyl group, and these phenyl group, alkyl group and alkenyl group are substituted with one or more of halogen atom, hydroxyl group, mercapto group, carboxyl group, nitro group, sulfonic acid group, etc. Groups and the like.

As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, etc. can be mentioned, for example.
As said alkyl group, a C1-C10 alkyl group is preferable, and a methyl group, an ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t- A linear or branched alkyl group having 1 to 6 carbon atoms such as a butyl group is more preferable.
Moreover, as said alkenyl group, a C2-C10 alkenyl group is preferable, C2-C6 linear or branched, such as a vinyl group, a propenyl group, 1-butenyl group, 2-butenyl group, etc. The alkenyl group is more preferable.
Moreover, as said amino group, a primary amino group is preferable and C1-C6 linear or branched, such as an aminomethyl group, 2-aminoethyl group, 3-aminopropyl group, 4-aminobutyl group, etc. A primary amino group having a shape is more preferable.
The acyl group is preferably an acyl group having 2 to 10 carbon atoms, and more preferably an aliphatic or aromatic acyl group having 2 to 6 carbon atoms such as an acetyl group, a propionyl group, a butyryl group, or a benzoyl group.

The monovalent organic group R ^13, for example, an alkyl group, an alkenyl group, an alicyclic group, aromatic hydrocarbon group, and a heterocyclic group.
Examples of the alkyl group include those having 1 to 6 carbon atoms such as methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group and t-butyl group. A chain or branched alkyl group is preferred.
The alkenyl group is preferably a linear or branched alkenyl group having 2 to 6 carbon atoms such as a vinyl group, a propenyl group, a 1-butenyl group, or a 2-butenyl group. As said alicyclic group, C4-C10 alicyclic groups, such as a cyclopentyl group and a cyclohexyl group, are preferable.
As said aromatic hydrocarbon group, C6-C12 aromatic hydrocarbon groups, such as a phenyl group, 1-naphthyl group, and 2-naphthyl group, are preferable.
Examples of the heterocyclic group include 2-furanyl group, tetrahydro-2-furanyl group, furfuryl group, tetrahydrofurfuryl group, thiofurfuryl group, 2-pyranyl group, tetrahydro-2-pyranyl group, 2-pyranylmethyl group, A 4- to 10-membered heterocyclic group such as a tetrahydro-2-pyranylmethyl group is preferred.

The polymer for the lower layer film (β) can be produced, for example, by the following method. However, the manufacturing method of the polymer for lower layer films (β) is not limited to these methods.
Production method (a): (a-1) After condensing acenaphthylenes and aldehydes together with other aromatic compounds capable of cocondensation in the presence of an acid catalyst, the polymer may be used alone or in combination. Polymerization with other polymerizable monomers, or (a-2) Acenaphthylenes may be polymerized alone or with other copolymerizable monomers, and this polymer and aldehydes can be optionally co-condensed A method of condensing together with other aromatic compounds in the presence of an acid catalyst to obtain a polymer for lower layer film (β-1).
Production method (b): A method of condensing acenaphthylenes and aldehydes together with other aromatic compounds that can be co-condensed in the presence of an acid catalyst to obtain a polymer for lower layer film (β-2) .
Production method (c): A method of condensing acenaphthenes and aldehydes together with other aromatic compounds that can be co-condensed in the presence of an acid catalyst to obtain a polymer for lower layer film (β-3) . The polymer for the lower layer film (β-4) can be obtained by polymerizing the acenaphthylenes alone or together with other monomers capable of copolymerization in the method (a-2).

The polymerization in the production method (a) can be carried out in an appropriate polymerization form such as bulk polymerization or solution polymerization by radical polymerization, anionic polymerization, cationic polymerization or the like.
In the production method (a), the Mw of the polymer obtained by condensing the acenaphthylenes and aldehydes in the step (a-1) together with other aromatic compounds optionally co-condensable and the step (a-2) Mw of a polymer obtained by polymerizing acenaphthylenes alone or together with other monomers capable of copolymerization is appropriately selected according to the desired properties of the lower layer film, but is usually 100 to 10,000, preferably 2,000. ~ 5,000.

The condensation reaction in the production methods (a) to (c) is performed by heating in the presence of an acid catalyst, in the absence of a solvent or in a solvent, preferably in a solvent.
Examples of the acid catalyst include mineral acids such as sulfuric acid, phosphoric acid and perchloric acid; organic sulfonic acids such as p-toluenesulfonic acid; carboxylic acids such as formic acid and oxalic acid.
Although the usage-amount of an acid catalyst is suitably adjusted with the kind of acids to be used, 0.001-10,000 weight part normally with respect to 100 weight part of acenaphthylenes or acenaphthenes, Preferably it is 0.01-1. 1,000 parts by weight.

The solvent used in the condensation reaction of the production methods (a) to (c) is not particularly limited as long as the condensation reaction is not inhibited. For example, aldehydes such as phenol resin, melamine resin, amino resin, etc. In addition to the solvents conventionally used for the synthesis of resins made from styrene, more specifically, the solvents exemplified for the composition solution of the radiation-sensitive resin composition of the present invention, and cyclic ethers such as tetrahydrofuran and dioxane Etc. Further, when the acid catalyst used is a liquid such as formic acid, this acid catalyst can also serve as a solvent.
These solvents can be used alone or in admixture of two or more.
The reaction temperature of the condensation reaction in the production methods (a) to (c) is usually 40 ° C to 200 ° C. Moreover, although reaction time is suitably adjusted with reaction temperature, it is 30 minutes-72 hours normally.

The Mw of the polymer for lower layer film (β) is usually 500 to 100,000, preferably 5,000 to 50,000.
The lower layer polymer (β) can be used alone or in admixture of two or more.

When forming the lower layer film, a solution in which the polymer for the lower layer film is dissolved in a solvent together with an additive to be described later (hereinafter referred to as “the composition solution for forming the lower layer film”) is usually used. The The solvent used in the lower layer film forming composition solution is not particularly limited as long as it can dissolve the polymer for the lower layer film and the additive component.
Ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether;
Ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, ethylene glycol mono-n-butyl ether acetate;
Diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether;
Propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether;

Propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol di-n-propyl ether, propylene glycol di-n-butyl ether;
Propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoether ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-n-butyl ether acetate;
Lactic acid esters such as methyl lactate, ethyl lactate, n-propyl lactate, i-propyl lactate, n-butyl lactate, i-butyl lactate;
Methyl formate, ethyl formate, n-propyl formate, i-propyl formate, n-butyl formate, i-butyl formate, n-amyl formate, i-amyl formate, methyl acetate, ethyl acetate, n-propyl acetate, i-acetate Propyl, n-butyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, n-hexyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, n propionate -Aliphatic carboxylic acid esters such as butyl, i-butyl propionate, methyl butyrate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n-butyl butyrate, i-butyl butyrate;

Ethyl hydroxyacetate, ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, ethyl methoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate , Ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, 3-methoxypropyl acetate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3- Other esters such as methoxybutyl propionate, 3-methyl-3-methoxybutyl butyrate, methyl acetoacetate, methyl pyruvate, ethyl pyruvate;
Aromatic hydrocarbons such as toluene and xylene;
Ketones such as methyl ethyl ketone, 2-pentanone, 2-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone;
Amides such as N-methylformamide, N, N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone;
Examples include lactones such as γ-butyrolactone.

Among these solvents, preferred solvents include ethylene glycol monoethyl ether acetates, ethyl lactate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, 2-heptanone, cyclohexanone and the like.
The said solvent can be used individually or in mixture of 2 or more types.

  The amount of the solvent used in the composition for forming the lower layer film is such that the total solid concentration in the solution is usually 0.01 to 70% by weight, preferably 0.05 to 60% by weight, more preferably 0.1 to 0.1%. The range is 50% by weight.

In the composition solution for forming the lower layer film, if necessary, a crosslinking agent, a polymer other than the polymer for the lower layer film, a radiation absorber, a surfactant, an acid generator, a storage stabilizer, an antifoaming agent, an adhesive Various additives such as auxiliaries can be blended.
The lower layer film-forming composition solution is usually filtered through a filter having a pore diameter of about 0.1 μm and used for forming the lower layer film.

Method for forming resist pattern As a preferred method for forming a resist pattern using the radiation-sensitive resin composition of the present invention, for example,
1) A step of applying a composition solution for forming a lower layer film on a substrate and baking the obtained coating film to form a lower layer film. 2) A composition solution of a radiation sensitive resin composition is formed on the lower layer film. A step of applying and prebaking the obtained coating film to form a coating (hereinafter referred to as “resist coating”), 3) a step of selectively exposing the resist coating to radiation through an exposure mask, and 4 The method may include a step of developing the exposed resist film to form a resist pattern, and 5) a step of etching the lower layer film using the resist pattern as a mask, if necessary.
Hereinafter, this method will be described more specifically.

The substrate used for forming the resist pattern is not particularly limited, and examples thereof include inorganic substrates such as silicon oxide films and interlayer insulating films.
In the step 1), the composition solution for forming the lower layer film is applied on the substrate by an appropriate method such as spin coating, cast coating, roll coating, etc., and then the obtained coating film is baked and coated. The lower layer film is formed by volatilizing the solvent in the film.
The baking temperature at this time is, for example, 90 to 500 ° C, preferably 200 to 450 ° C. The film thickness of the lower layer film is usually 10 to 10,000 nm, preferably 50 to 1,000 nm.

Next, in the step 2), the composition solution of the radiation-sensitive resin composition is applied onto the lower layer film, for example, by spin coating, cast coating, roll coating so that the resulting resist film has a predetermined film thickness. After applying by an appropriate method such as the above, the resulting coating film is pre-baked to evaporate the solvent in the coating film, thereby forming a resist film.
Although the temperature of the prebaking in this case is suitably adjusted according to the composition of the radiation sensitive resin composition etc. to be used, it is 30-200 degreeC normally, Preferably it is 50-160 degreeC.
The film thickness of the resist film is usually 10 to 10,000 nm, preferably 50 to 1,000 nm, and particularly preferably 70 to 300 nm.

Next, in step 3), the resist film is selectively exposed to radiation through an exposure mask.
Depending on the composition of the radiation-sensitive resin composition to be used, the radiation used for exposure is appropriately selected from visible rays, ultraviolet rays, far ultraviolet rays, X-rays, electron beams, γ rays, molecular beams, ion beams, etc. Although it can be used, KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm), far-ultraviolet rays such as ultra-far ultraviolet rays (EUV), or electron beams are preferable. ArF excimer laser and F ₂ excimer laser are preferable.

Next, in step 4), the resist film after exposure is developed to form a resist pattern.
Examples of the developer used for development include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, Methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo -[4.3.0] -5 An alkaline aqueous solution in which nonene or the like is dissolved can be mentioned.
Further, an appropriate amount of a water-soluble organic solvent, for example, an alcohol such as methanol or ethanol, or a surfactant can be added to these alkaline aqueous solutions.
Thereafter, the desired resist pattern is formed by washing and drying.
In this step, post-baking may be performed before development in order to improve resolution, pattern shape, developability, and the like.
Although the temperature of post-baking is suitably adjusted according to the composition etc. of the radiation sensitive resin composition used, it is 30-200 degreeC normally, Preferably it is 50-160 degreeC.

Further, in the step 5), if desired, a desired pattern is formed by etching the lower layer film using gas plasma such as fluorine plasma, chlorine plasma, bromine plasma or the like using the obtained resist pattern as a mask. .
However, the method for forming a resist pattern in the present invention is not limited to the method described above.

  The radiation-sensitive resin composition of the present invention has a particularly high resolution while maintaining high transparency to radiation and high dry etching resistance, and greatly contributes to a lithography process that is expected to become increasingly finer in the future. .

Synthesis Example 1 (Synthesis of polysiloxane (α))
In a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, 8.34 g of the compound of the following formula (30), 12.92 g of the compound of the following formula (31), 8.75 g of methyltriethoxysilane, 4- After adding 30 g of methyl-2-pentanone and 7.20 g of a 1.75 wt% oxalic acid aqueous solution and reacting at 80 ° C. for 6 hours with stirring, the reaction vessel was ice-cooled to stop the reaction. Thereafter, the reaction solution was transferred to a separatory funnel, the aqueous layer was discarded, and ion-exchanged water was further added and washed, and washing was repeated until the reaction solution became neutral. Thereafter, the organic layer was distilled off under reduced pressure to obtain 18.5 g of polysiloxane (α).

〔式（３０）において、ケイ素原子はテトラシクロ[ ４．４．０．１^2,5 ．１^7,10 ]ドデカン環の３−位あるいは４−位に結合している。〕

[In the formula (30), the silicon atom is tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] It is bonded to the 3-position or 4-position of the dodecane ring. ]

〔式（３１）において、ケイ素原子はビシクロ[ ２．２．１ ]ヘプタン環の２−位あるいは３−位に結合している。〕

[In the formula (31), the silicon atom is bonded to the 2-position or 3-position of the bicyclo [2.2.1] heptane ring. ]

With respect to this polysiloxane (α), ¹ H-NMR spectrum (chemical shift σ), Mw and Mn were measured and found to be as follows.
σ: 2.3 ppm (CH ₂ C (CF ₃ ) ₂ group), 1.4 ppm (t-butyl group), 0.2 ppm (SiCH ₃ group).
Mw: 2,300.
Mw / Mn: 1.1.
This polysiloxane (α) is referred to as “polysiloxane (α-1)”.

Synthesis Example 2 (Synthesis of polysiloxane (α))
In a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, 3.84 g of the compound of the above formula (30), 7.93 g of the compound of the above formula (31), 3.22 g of methyltriethoxysilane, 4- After adding 15 g of methyl-2-pentanone and 3.32 g of a 1.75 wt% oxalic acid aqueous solution and reacting at 80 ° C. for 6 hours with stirring, the reaction vessel was ice-cooled to stop the reaction. Thereafter, the reaction solution was transferred to a separating funnel, the aqueous layer was discarded, and ion-exchanged water was further added and washed, and washing was repeated until the reaction solution became neutral. Subsequently, the organic layer was distilled off under reduced pressure to obtain 8.24 g of polysiloxane (α).

With respect to this polysiloxane (α), ¹ H-NMR spectrum (chemical shift σ), Mw and Mn were measured and found to be as follows.
σ: 2.3 ppm (CH ₂ C (CF ₃ ) ₂ group), 1.4 ppm (t-butyl group), 0.2 ppm (SiCH ₃ group).
Mw: 2,200.
Mw / Mn: 1.1.
This polysiloxane (α) is referred to as “polysiloxane (α-2)”.

Synthesis Example 3 (Synthesis of acid generator (B1))
A solution prepared by dissolving 20 g of triphenylsulfonium chloride in 500 ml of water was placed in an eggplant flask, and 20 g of sodium 1,1,2,2-tetrafluoro-2- (norbornan-2-yl) ethanesulfonate prepared separately was then added. 500 ml of aqueous solution was dropped at room temperature and stirred for 30 minutes. Thereafter, the reaction solution was extracted with ethyl acetate, the organic layer was washed twice with water, and then distilled under reduced pressure to obtain triphenylsulfonium 1,1,2,2-tetrafluoro-2-formaldehyde represented by the following formula (34). (Norbornan-2-yl) ethanesulfonate (43% yield) was obtained as a colorless highly viscous oil.

Evaluation Example 1 (Resolution by ArF excimer laser exposure)
900 parts by weight of the polysiloxane (α) and 2-heptanone shown in Table 1-1 or Table 1-2 are mixed with the acid generator (B1), acid generator (B2) and Table 1-1 or Table 1-2. A composition solution was prepared by uniformly mixing with an acid diffusion controller.
Next, each composition solution was applied by spin coating on a silicon wafer substrate (Si) or a substrate (lower layer film a) on which the lower layer film was previously formed on the surface of the silicon wafer, and maintained at 140 ° C. Above, each was pre-baked for 90 seconds to form a resist film having a thickness of 100 nm.
Here, the lower layer film A is a film formed by applying a commercially available antireflection film DUV-30J (film thickness: 520 mm) and baking at 205 ° C. for 60 seconds.
Thereafter, each resist film was exposed to an ArF excimer laser (wavelength 193 nm, NA = 0.60, σ = 0.70) while changing the exposure amount, and each was heated on a hot plate maintained at 110 ° C. for 90 seconds. After post-baking, development was performed with a 2.38 wt% tetramethylammonium hydroxide aqueous solution to form a line and space pattern (1L1S), and the resolution was evaluated.
The evaluation results are shown in Table 1-1 and Table 1-2.

Each component other than polysiloxane in Table 1-1 and Table 1-2 is as follows.
Acid generator (B1)
B1-5: Compound acid generator of formula (34) (B2)
B2-1: Triphenylsulfonium 10-camphorsulfonate acid diffusion controller C-1: Tri-N-octylamine

＊ 酸発生剤（Ｂ）の合計量に対するモル％（以下同様）。

* Mole% relative to the total amount of the acid generator (B) (hereinafter the same).

Evaluation Example 2 (Resolution by F ₂ excimer laser exposure)
A polysiloxane (α) shown in Table 2 and 900 parts by weight of 2-heptanone are uniformly mixed with an acid generator (B1), an acid generator (B2) and an acid diffusion controller shown in Table 2 to obtain a composition solution. Was prepared.
Next, the composition solution was applied by spin coating onto a substrate (underlayer film a) on which a lower layer film i was previously formed on the silicon wafer surface, and prebaked for 90 seconds on a hot plate maintained at 140 ° C., A resist film having a thickness of 100 nm was formed.
Thereafter, the resist film is exposed using a binary mask as a reticle and an F ₂ excimer laser (wavelength: 157 nm, NA = 0.60, σ = 0.70) while changing the exposure amount to 110 ° C. After post-baking for 90 seconds on the held hot plate, development was performed with a 2.38 wt% tetramethylammonium hydroxide aqueous solution to form a line and space pattern (1L1S), and the resolution was evaluated. .
The evaluation results are shown in Table 2.
Each component other than polysiloxane (α) in Table 2 is as described above.