TW201925410A - Photo-acid generator, resist composition, and method for producing device using said resist composition - Google Patents

Abstract

Provided are: a compound which can be used suitably as a photodegradable base in a resist composition that has good sensitivity to an active energy, has excellent resolution in lithography and enables the reduction in line width roughness (LWR) in a fine pattern; and a resist composition prepared using the compound. A photo-acid generator containing an onium salt compound represented by formula (1). (In formula (1), R1 and R2 independently represent any one selected from the group consisting of a hydrogen atom, a linear, branched or cyclic alkyl group which has 1 to 30 carbon atoms and may have a substituent, a linear, branched or cyclic alkenyl group which has 5 to 30 carbon atoms and may have a substituent, an aryl group which has 5 to 30 carbon atoms and may have a substituent, and a heteroaryl group which has 3 to 30 carbon atoms and may have a substituent, wherein at least one of R1 and R2 is not a hydrogen atom, a methylene group in at least one of R1 and R2 may be substituted by a bivalent hetero-atom-containing group when each of R1 and R2 has a methylene group, and R1 and R2 may be directly bonded to each other via a single bond or may form a cyclic structure through at least one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen-atom-containing group, a methylene group and a carbonyl group in conjunction with a nitrogen atom to which both of R1 and R2 are bonded; L represents a bivalent linking group represented by -(CF2)n-; n represents an integer of 1 or more; and S and M+ independently represent a monovalent onium cation).

Description

 Photoacid generator, resist composition, and method of manufacturing apparatus using the same  

Several aspects of the invention relate to photoacid generators, and more particularly to photoacid generators suitable for use in resist compositions for lithography. Further, several aspects of the invention relate to a resist composition containing the above photoacid generator and a method of producing an apparatus using the same.

In recent years, photolithography technology has been actively used to manufacture display devices such as liquid crystal displays (LCDs) and organic EL displays (OLEDs) and formation of semiconductor elements using photoresist. In the above-described electronic component and electronic product package, light such as i-ray having a wavelength of 365 nm, h-ray (405 nm) having a longer wavelength, and g-ray (436 nm) are widely used as the active energy ray.

With the high integration of devices, the lithography technology is becoming more and more demanding, including KrF excimer laser (wavelength 248nm), ArF excimer laser (wavelength 193nm), and extreme ultraviolet light (hereinafter also referred to as "EUV". High-energy rays such as "wavelength is 13.5 nm" and electron beams (hereinafter also referred to as "EB") are used for exposure. The use of these short-wavelength light, especially electron beam or extreme ultraviolet (EUV) lithography, enables single-pattern fabrication, so there will be a greater need for high sensitivity to electron beam or extreme ultraviolet (EUV) display in the future. Resist composition.

As the exposure light source is shortened in wavelength, the resist composition is required to improve the lithographic characteristics to have high sensitivity to an exposure light source and resolution to reproduce a fine-sized pattern. As a resist composition that satisfies such a demand, a chemically amplified resist using a photoacid generator is known (Patent Document 1).

However, in the rapid development of miniaturization, there has been a problem that, for a chemically amplified resist using a photoacid generator, an acid generated by exposure diffuses in the resist to seriously affect the lithography performance. The line width roughness (LWR) characteristics of the contrast and line patterns are lowered. Therefore, Patent Document 2 proposes to improve the resolution by including an acid diffusion controlling agent in the resist composition for the purpose of appropriately controlling the diffusion of the acid generated by the photoacid generator. On the other hand, if the acid diffusibility is excessively controlled, the production efficiency of acid may be lowered, resulting in a decrease in contrast.

Therefore, Patent Document 3 proposes a scheme for improving contrast by using a photodegradable base which loses acid diffusion controllability due to exposure decomposition as an acid diffusion controlling agent. The photodegradable base is a weak acid sulfonium salt. The photodegradable base can be used as an acid diffusion controlling agent because a strong acid generated by exposure of another photoacid generator is exchanged with the above-mentioned weak acid cerium salt, and is replaced by a strong acid having a high acidity into a weak acid, thereby suppressing acid instability. The acid decomposition reaction of the group shortens the acid diffusion distance and acts as a quencher.

 [Prior Art Literature]    [Patent Literature]  

Patent Document 1: Japanese Patent Laid-Open No. Hei 9-90637

Patent Document 2: Japanese Laid-Open Patent Publication No. 2004-191764

Patent Document 3: Japanese Laid-Open Patent Publication No. 2010-66492

Sensitivity, resolution, and pattern performance such as LWR are trade-offs. Therefore, the conventional chemical smear-type resist composition is difficult to satisfy the characteristics of sensitivity, resolution, and pattern properties such as LWR. The acid diffusion controlling agent proposed in the above Patent Document 2 has a problem of poor contrast. Further, the photodegradable base proposed in the above Patent Document 3 has a problem that the acid diffusion length control is insufficient.

An object of several aspects of the present invention is to provide a photoacid generator of a resist composition excellent in sensitivity, resolution, and pattern performance.

Further, an object of several aspects of the present invention is to provide a resist composition containing the photoacid generator and a method for producing an apparatus using the above resist composition.

The present inventors have conducted intensive studies to solve the above problems, and as a result, it has been found that a photoacid generator containing a specific onium salt compound as a resist composition can improve the sensitivity, resolution, and pattern properties. Several aspects of the invention.

That is, one aspect of the present invention is a photoacid generator containing an onium salt compound represented by the following formula (1).

In the above formula (1), R ¹ and R ² are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of them is not a hydrogen atom.

When R ¹ and R ² described above have a methylene group, at least one methylene group of the above R ¹ and R ² may be substituted with a divalent hetero atom-containing group.

The above R ¹ and R ² may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be at least selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group and a carbonyl group. Either of them together with the nitrogen atom to which they are bonded form a ring structure.

L is a divalent linking group represented by -(CF ₂ ) _n -, wherein n is an integer of 1 or more.

M ⁺ is a monovalent phosphonium cation.

Further, another aspect of the invention is a photoacid generator and a resist composition containing the above onium salt compound.

In another aspect of the invention, the above resist composition further contains an acid-reactive compound.

In another aspect of the invention, the acid-reactive compound is selected from the group consisting of a compound having a protective group deprotected by an acid, a compound having a polymerizable group polymerized by an acid, and a cross-linking action due to an acid. At least one of the crosslinking agents.

Further, another aspect of the present invention is a method of manufacturing a device comprising: a step of forming a resist film on a substrate using the above resist composition; a step of exposing the resist film using an active energy ray; and The step of developing the exposed resist film.

Another aspect of the invention is a process for producing the above sulfonium salt compound.

In another aspect of the invention, the method for producing an onium salt compound comprises the steps of: salt-exchange a compound represented by the following formula (2) with an ionic compound M ⁺ X ^- to obtain a formula (1): Anthraquinone salt compound.

In the above formula (1), R ¹ and R ² are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of them is not a hydrogen atom.

When R ¹ and R ² described above have a methylene group, at least one methylene group of the above R ¹ and R ² may be substituted with a divalent hetero atom-containing group.

The above R ¹ and R ² may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be at least selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group and a carbonyl group. Either of them together with the nitrogen atom to which they are bonded form a ring structure.

L is a divalent linking group represented by -(CF ₂ ) _n -, wherein n is an integer of 1 or more.

M ⁺ is a monovalent phosphonium cation.

The above-described formula (2), R ^1, R ^2, and R L is selected from the formula (1) is ^1, R ² and L are the same selectable items.

Q ⁺ is a monovalent cation other than M ^{+ of the} above formula (1).

M ⁺ X ^- M ⁺ and M of the above formula (1) is the same as ^+, X ^- is a monovalent anion.

In another aspect of the invention, a salt compound represented by the following formula (2) which is a synthetic intermediate of the above sulfonium salt compound can be used.

[化3]

The above-described formula (2), R ^1, R ^2, and R L is selected from the formula (1) is ^1, R ² and L are the same selectable items.

Q ⁺ is a monovalent cation other than M ^{+ of the} above formula (1).

In another aspect of the invention, the above M ⁺ is a phosphonium cation having any one selected from the group consisting of sulfur (S), iodine (I), selenium (Se), and tellurium (Te).

In another aspect of the invention, the above M ⁺ is any one of a phosphonium cation or an iodonium cation.

In another aspect of the invention L is -(CF ₂ ) ₂ - or -(CF ₂ ) ₃ -.

In another aspect of the invention, the above Q ⁺ is an ammonium cation represented by the following formula (3).

In the above formula (3), R ³ to R ⁶ are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any of the 3 to 30 heteroaryl groups, and at least the latter is not a hydrogen atom.

When R ³ to R ⁶ have a methylene group, at least one methylene group of the above R ³ to R ⁶ may be substituted with a divalent hetero atom-containing group.

Two of the above R ³ to R ⁶ may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be selected from an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group, and At least any of the carbonyl groups together with the nitrogen atom to which they are bonded form a ring structure.

The photoacid generator of one aspect of the present invention contains an onium salt compound having a specific anion structure, and thus is excellent in sensitivity, resolution, and pattern properties.

Several aspects of the invention are described below.

<1> Photoacid generator

The photoacid generator of one aspect of the invention is characterized by containing a phosphonium salt compound having a specific structure.

The photoacid generator described above is capable of improving sensitivity, resolution, and pattern properties by containing a phosphonium salt compound having a specific anion structure. More specifically, the photoacid generator can appropriately control the acid diffusibility by having the anion structure represented by the above formula (1). Further, when used in combination with other specific photoacid generators, the photoacid generator can function as a photodegradable base, so that the characteristics of sensitivity, resolution, and pattern performance can be further improved.

The photoacid generator described above decomposes under exposure of the active energy ray. Therefore, when a resist composition containing a photoacid generator of several aspects of the present invention as a photodecomposable base and further containing another photoacid generator is used for the photoresist, in the exposed portion, the above The photodecomposable alkali decomposes, loses the acid diffusion controllability, and the secondary electrons generated by the decomposition act on other photoacid generators, thereby further improving the acid generating effect of other photoacid generators. On the other hand, in the unexposed portion, the photodegradable base is a salt having a weak conjugate base than other photoacid generators, and therefore can react with an acid generated by another photoacid generator to cause other photoacid generators. Acid deactivated and used as an acid diffusion control agent. Therefore, when the photoacid generator of one embodiment of the present invention is used as a photodecomposable base in a resist composition, a resist composition excellent in sensitivity, resolution, and pattern forming ability can be obtained.

Several aspects of the invention are specifically described below, but the invention is not limited thereto.

<1-1> Anion of bismuth salt compound

The anion of the onium salt compound of one aspect of the invention is represented by the above formula (1).

Examples of the linear alkyl group having 1 to 30 carbon atoms of R ¹ and R ² include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group and n-dodecane. A straight chain alkyl group. Further, at least one carbon-carbon single bond in the above linear alkyl group may be substituted with a carbon-carbon double bond to form an alkenyl group.

Examples of the branched alkyl group having 1 to 30 carbon atoms of R ¹ and R ² include an isopropyl group, an isobutyl group, a t-butyl group, an isopentyl group, a t-amyl group, a 2-ethyloctyl group, and 2 a branched alkyl group such as an ethyl fluorenyl group. Further, at least one carbon-carbon single bond in the above branched alkyl group may be substituted with a carbon-carbon double bond to form an alkenyl group.

Examples of the cyclic alkyl group having 1 to 30 carbon atoms of R ¹ and R ² include a cyclic alkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group and a decahydronaphthyl group. .

Examples of the cyclic alkyl group include a spirocyclic cyclic alkyl group such as a spiro[3,4]octyl group and a spirobicyclopentyl group; a norbornyl group, a tricyclic fluorenyl group, and a tetracyclododecyl group; A bridged cyclic alkyl group such as an adamantyl group; or a cyclic alkyl group such as a condensed cyclic alkyl group having a decalin and a steroid skeleton as shown below. Further, at least one carbon-carbon single bond in the branched alkyl group may be substituted with a carbon-carbon double bond to form an alkenyl group.

Further, a divalent hetero atom-containing group may be contained in place of at least one methylene group of these alkyl groups. As the above hetero atom-containing group, it is selected from the group consisting of -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O- , -O-CO-NH-, -S-, -SO-, -S(O) ₂ -, -S(O) ₂ O-, and -CO-O-CH ₂ -CO-O-, etc. At least one. These groups may be contained in an appropriate combination. In addition, these substituents may also be contained in the ring structure.

Examples of the divalent hetero atom-containing group-containing alkyl group include an alkoxy group; an alkylcarbonyloxy group; and an alkyl group having a heterocyclic structure such as a lactone structure, a sultone structure, and an indoleamine structure. .

Examples of the aryl group having 5 to 30 carbon atoms include monovalent aryl groups such as a cyclopentadienyl group, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group and a fluorenyl group. Further, a monovalent heteroaryl group having 3 to 30 carbon atoms which contains a hetero atom in place of the carbon atom in the above aryl ring may be used. The heteroaryl group may, for example, be a monovalent heteroaryl group having a skeleton such as fluoran, thiophene, imidazole, pyran, chromene, thiophene, dibenzothiophene or xanthene.

The substituent which the above-mentioned alkyl group, alkenyl group, aryl group and heteroaryl group may have is a linear or cyclic alkyl group (R ^Sp ); a linear or cyclic alkenyl group; and the skeleton contains a group selected from -O -, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -N(R _{^{Sp) 2 -, - N (}} Ar Sp) 2 -, - S -, - SO- and -SO ₂ - in at least one hetero atom of the alkyl group in place of (R ^Sp) at least one alkylene a methyl group; an alkenyl group having a hetero atom-containing group in place of at least one methylene group of the above alkenyl group; an aryl group (Ar ^Sp ); the ring structure of the aryl group may contain a hetero atom instead of a heteroaryl group of a carbon atom; a hydroxyl group, a halogen atom, and the like. In -NHCO-, -CONH-, -NH-CO-O-, and -O-CO-NH- in the above hetero atom-containing group, the hydrogen atom may be substituted by R ^Sp or Ar ^Sp .

Examples of the above R ^Sp include a linear, branched or cyclic alkyl group which is the same as the above R. Examples of Ar ^Sp include the same aryl groups as those of R ¹ and R ² described above. Note that, as R ¹ and R ² alkyl group, alkenyl group, aryl group and heteroaryl group having a substituent at R ¹ and R ² is preferably the total number of carbon atoms of the carbon atoms including the substituent include number.

Further, R ¹ and R ² alkyl group having a substituent at R ¹ and R ² are the total number of carbon atoms is 1 to 30, preferably 4 to 20, more preferably 4 to 12.

Further, R ¹ and R ² is an alkenyl group having a substituent group when R ¹ and R ² are the total number of carbon atoms is 2 to 30, preferably 5 to 20, more preferably 6 to 12.

Further, R ¹ and R ² is an aryl group having a substituent group when R ¹ and R ² are the total number of carbon atoms is 5 to 30, preferably 6 to 14, more preferably 6 to 11.

Further, R ¹ and R ² having a heteroaryl substituent when R ¹ and R ² are the total number of carbon atoms is from 3 to 30, preferably 4 to 13, more preferably from 5 to 10.

The alkyl group (R ^Sp ), the alkenyl group and the aryl group (Ar ^Sp ) as a substituent include the same groups as the above-mentioned alkyl group of R ¹ and R ² , the above alkenyl group and the above aryl group.

Examples of the halogen atom of the substituent include a fluorine atom, a chlorine atom, a bromine atom and the like.

R ¹ and R ² may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be at least any one selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group and a carbonyl group. One forms a ring structure together with the nitrogen atoms to which they are bonded.

The nitrogen atom-containing group may be a group containing a nitrogen atom in the above hetero atom-containing group. For example, nitrogen-containing two such as -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -N(R ^Sp ) ₂ -, -N(Ar ^Sp ) ₂ - may be mentioned. Price group. In the above -NHCO-, -CONH-, -NH-CO-O- and -O-CO-NH-, the hydrogen atom may be substituted by the above R ^Sp or Ar ^Sp . It should be noted that R is selected from the same optional items as R ¹ and R ² described above.

L is a divalent linking group represented by -(CF ₂ ) _n -, and n is an integer of 1 or more. n is preferably 2 or more, and more preferably 3 or more.

Specific examples of the anion of the onium salt compound represented by the above formula (1) include the following anions.

【化6】

<1-2> cation of bismuth salt compound

M ⁺ is a monovalent phosphonium cation. The above M ⁺ is preferably a phosphonium cation having any atom selected from the group consisting of sulfur (S), iodine (I), selenium (Se), and tellurium (Te).

Examples of the phosphonium cation having a sulfur (S) atom include the phosphonium cations shown below.

【化7】

In the above formula, R ^a1 to R ^a3 each independently may be a linear, branched or cyclic alkyl group having or not having a substituent; a linear, branched or cyclic alkenyl group having or not having a substituent; An aryl group with or without a substituent; a heteroaryl group with or without a substituent, and the like.

The alkyl group, the alkenyl group, the aryl group and the heteroaryl group of R ^a1 to R ^a3 may be the same as the alkyl group, the alkenyl group, the aryl group and the heteroaryl group as the above R ¹ .

Specific examples of the phosphonium cation include, for example, a trimethyl phosphonium cation, a tributyl phosphonium cation, a dimethyl (2-oxocyclohexyl) phosphonium cation, a bis(2-oxocyclohexyl)methyl phosphonium cation, (10) -Camphanoyl)methyl(2-oxocyclohexyl)phosphonium cation, (2-norbornyl)methyl(2-oxocyclohexyl)phosphonium cation, triphenylphosphonium cation, diphenyl a tolyl sulfonium cation, a diphenyldimethylphenylphosphonium cation, a mesitylene diphenylphosphonium cation, a (tert-butylphenyl)diphenylphosphonium cation, an (octylphenyl)diphenylphosphonium cation, (cyclohexylphenyl)diphenylphosphonium cation, biphenyldiphenylphosphonium cation, (hydroxymethylphenyl)diphenylphosphonium cation, (methoxymethylphenyl)diphenylphosphonium cation, Ethylphenyl)diphenylphosphonium cation, (benzylidenephenyl)diphenylphosphonium cation, (hydroxycarbonylphenyl)diphenylphosphonium cation, (methoxycarbonylphenyl)diphenylphosphonium a cation, a (trifluoromethylphenyl)diphenylphosphonium cation, a (fluorophenyl)diphenylphosphonium cation, a (chlorophenyl)diphenylphosphonium cation, a (bromophenyl)diphenylphosphonium cation, Iodophenyl)diphenylphosphonium cation, pentafluorophenyldiphenylphosphonium cation, (hydroxyphenyl)diphenylphosphonium cation, (methoxyphenyl)diphenylphosphonium cation, (butoxyphenyl) a diphenylphosphonium cation, an (ethoxycarbonyloxyphenyl)diphenylphosphonium cation, a (benzimidyloxyphenyl)diphenylphosphonium cation, (dimethylaminomethylphenylphenyl) Phenylphosphonium cation, (acetamidophenyl) diphenylphosphonium cation, phenyl bis-methyl sulfonium cation, phenyl bis dimethyl hydrazine cation, bis-trimethylphenyl sulfonium cation, double (tert-butyl) Phenyl phenyl cation, bis(octylphenyl)phenyl sulfonium cation, bis(cyclohexylphenyl)phenyl sulfonium cation, diphenylphenyl sulfonium cation, bis(hydroxymethylphenyl) Phenylphosphonium cation, bis(methoxymethylphenyl)phenylphosphonium cation, bis(ethylmercaptophenyl)phenylphosphonium cation, bis(benzimidylphenyl)phenylphosphonium cation, bis(hydroxyl) a carbonylphenyl)phenylphosphonium cation, a bis(methoxycarbonylphenyl)phenylphosphonium cation, a bis(trifluoromethylphenyl)phenylphosphonium cation, a bis(fluorophenyl)phenylphosphonium cation, a bis ( chlorine a phenyl sulfonium cation, a bis(bromophenyl)phenylphosphonium cation, a bis(iodophenyl)phenylphosphonium cation, a dipentafluorophenylphenylphosphonium cation, a bis(hydroxyphenyl)phenylphosphonium cation, Bis(methoxyphenyl)phenylphosphonium cation, bis(butoxyphenyl)phenylphosphonium cation, bis(acetamidooxyphenyl)phenylphosphonium cation, bis(benzimidyloxybenzene) Phenylphosphonium cation, bis(dimethylaminomethylphenylphenyl)phenylphosphonium cation, bis(ethylguanidinophenyl)phenylphosphonium cation, trimethylphenylphosphonium cation, trimethylphenylphosphonium cation , trimestriphenylphenylphosphonium cation, tri(tert-butylphenyl)phosphonium cation, tris(octylphenyl)phosphonium cation, tris(cyclohexylphenyl)phosphonium cation, terphenyl sulfonium cation, tri Hydroxymethylphenyl sulfonium cation, tris(methoxymethylphenyl)phosphonium cation, tris(ethenylphenyl)phosphonium cation, tris(benzhydrylphenyl)phosphonium cation, tris(hydroxycarbonylbenzene) a ruthenium cation, a tris(methoxycarbonylphenyl)phosphonium cation, a tris(trifluoromethylphenyl)phosphonium cation, a tris(fluorophenyl)phosphonium cation, a tris(chlorophenyl)phosphonium cation, (bromophenyl)phosphonium cation, tris(iodophenyl)phosphonium cation, dipentafluorophenylphosphonium cation, tris(hydroxyphenyl)phosphonium cation, tris(methoxyphenyl)phosphonium cation, tris(butoxy) Phenyl) phosphonium cation, tris(ethinyloxyphenyl)phosphonium cation, tris(benzimidyloxyphenyl)phosphonium cation, tris(dimethylaminomethylphenylphenyl)phosphonium cation, tri Ethylaminophenyl) phosphonium cation, methyl diphenyl phosphonium cation, ethyl diphenyl phosphonium cation, butyl diphenyl phosphonium cation, hexyl diphenyl phosphonium cation, octyl diphenyl sulfonium cation, ring Hexyldiphenylphosphonium cation, 2-oxocyclohexyldiphenylphosphonium cation, norbornyl diphenylphosphonium cation, stanolol diphenylphosphonium cation, fluorenyldiphenylphosphonium cation, naphthyldiphenyl Base cation, decyldiphenylphosphonium cation, benzyldiphenylphosphonium cation, trifluoromethyldiphenylphosphonium cation, methoxycarbonylmethyldiphenylphosphonium cation, butoxycarbonylmethyldiphenyl Base cation, benzhydrylmethyldiphenylphosphonium cation, (methylthiophenyl)diphenylphosphonium cation, (phenylthiobenzene) a diphenylphosphonium cation, an (ethoxyphenylthiophenyl)diphenylphosphonium cation, a dimethylphenylphosphonium cation, a diethylphenylphosphonium cation, a dibutylphenylphosphonium cation, a dihexylbenzene Base cation, dioctylphenylphosphonium cation, dicyclohexylphenylphosphonium cation, bis(2-oxocyclohexyl)phenylphosphonium cation, dinorbornylphenylphosphonium cation, dinonanolylphenyl Ruthenium cation, dimercaptophenylphosphonium cation, dinaphthylphenylphosphonium cation, dibenzylphenylphosphonium cation, trifluoromethyldiphenylphosphonium cation, bis(methoxycarbonylmethyl)phenylphosphonium cation , bis(butoxycarbonylmethyl)phenylphosphonium cation, benzhydrylmethylphenylphosphonium cation, bis(methylthiophenyl)phenylphosphonium cation, bis(phenylthiophenyl)phenyl Ruthenium cation, bis(ethylmercaptophenylthiophenyl)phenylphosphonium cation, dimethyl(2-oxocyclohexyl)phosphonium cation, bis(2-oxocyclohexyl)methylphosphonium cation, (10-莰 醇 )) methyl (2-oxocyclohexyl) phosphonium cation, (2-norbornyl) methyl (2-oxocyclohexyl) phosphonium cation, trimethyl phosphonium cation, triethyl Ruthenium cation, tributyl phosphonium cation, dihexylmethyl phosphonium cation, trioctyl phosphonium cation, dicyclohexylethyl phosphonium cation, methyl tetrahydrothiophene cation, methyl tetrahydrothiophene cation, triphenyl oxygen Deuterium cation, bis[4-(diphenylfluorene)phenyl] sulfide-bis-cation, and the like. However, the phosphonium cation is not limited to this.

Examples of the phosphonium cation having an iodine (I) atom include the following iodonium cations.

[Chemical 8] R ^a2 -I ⁺ -R ^a1

In the above formula, R ^a1 to R ^a2 each independently may be a linear, branched or cyclic alkyl group having or not having a substituent; a linear, branched or cyclic alkenyl group having or not having a substituent; An aryl group having or not having a substituent, a heteroaryl group having or not having a substituent, and the like.

The alkyl group, the alkenyl group, the aryl group and the heteroaryl group of R ^a1 to R ^a2 may be the same as those of the alkyl group, the alkenyl group, the aryl group and the heteroaryl group as the above R ¹ .

Specific examples of the iodonium cation include a diphenyliodonium cation, a bis(tert-butylphenyl)iodonium cation, a (methoxyphenyl)phenyliodonium cation, and a (butoxyphenyl) group. a phenyl iodonium cation, a trifluoroethylphenyl iodonium cation, a pentafluorophenyl phenyl iodonium cation, or the like. However, the iodonium cation is not limited to this.

Examples of the phosphonium cation having a selenium (Se) atom include the selenium cations shown below.

In the above formula, R ^a1 to R ^a3 each independently may be a linear, branched or cyclic alkyl group having or not having a substituent; a linear, branched or cyclic alkenyl group having or not having a substituent; An aryl group having or not having a substituent, a heteroaryl group having or not having a substituent, and the like.

The alkyl group, the alkenyl group, the aryl group and the heteroaryl group of R ^a1 to R ^a3 may be the same as the alkyl group, the alkenyl group, the aryl group and the heteroaryl group as the above R ¹ .

Specific examples of the selenium cation include triphenyl selenium cation, tri-p-tolyl selenium cation, tri-o-tolyl selenium cation, tris(4-methoxyphenyl) selenium cation, and 1-naphthyl diphenyl selenium. Cationic, tris(4-fluorophenyl)selenium cation, tri-1-naphthyl selenium cation, tri-2-naphthyl selenium cation, tris(4-hydroxyphenyl) selenium cation, 4-(phenylthio)phenyl di Phenyl selenium cation, 4-(p-tolylthio)phenyldi-p-tolyl selenium cation, diphenyl benzamidine methyl selenium cation, diphenylbenzyl selenium cation, diphenylmethyl selenium cation, benzene Methylbenzyl selenide cation, 4-hydroxyphenylmethylbenzyl selenide cation, phenylmethyl benzamidine methyl selenium cation, 4-hydroxyphenylmethyl benzamidine methyl selenium cation, 4-methyl Oxyphenylmethyl benzamidine methyl selenide cation, dimethyl benzamidine methyl selenium cation, benzamidine methyl selenophenium cation, dimethyl benzyl selenium cation, benzyl four Hydrogen selenium cation, octadecylmethyl benzamidine methyl selenium cation, and the like. However, the selenium cation is not limited to this.

Examples of the phosphonium cation having a cerium (Te) atom include the phosphonium cations shown below.

In the above formula, R ^a1 to R ^a3 each independently may be a linear, branched or cyclic alkyl group having or not having a substituent; a linear, branched or cyclic alkenyl group having or not having a substituent; An aryl group having or not having a substituent, a heteroaryl group having or not having a substituent, and the like.

The alkyl group, the alkenyl group, the aryl group and the heteroaryl group of R ^a1 to R ^a3 may be the same as the alkyl group, the alkenyl group, the aryl group and the heteroaryl group as the above R ¹ .

Specific examples of the phosphonium cation include a triphenylphosphonium cation, a (2-methylphenyl)diphenylphosphonium cation, a (3-methylphenyl)diphenylphosphonium cation, and a (4-methylphenyl group). Diphenylphosphonium cation, (1,3,5-trimethylphenyl)diphenylphosphonium cation, tris(4-methylphenyl)phosphonium cation, tris(1,3,5-trimethylbenzene) a ruthenium cation, a (4-methoxyphenyl)diphenylphosphonium cation, a tris(4-ethoxyphenyl)phosphonium cation, a tris(2,6-dimethoxyphenyl)phosphonium cation, three (4-hydroxy-2-methylphenyl)phosphonium cation, tris(2,3,4,5,6-pentafluorophenyl)phosphonium cation, (1-naphthyl)diphenylphosphonium cation, phenyl di A benzopyrene cation, a (4-phenylindole) phenyldiphenylphosphonium cation, or the like. However, the phosphonium cation is not limited to this.

<1-3> bismuth salt compound

The onium salt compound represented by the above formula (1) is a compound having a specific structure, and thus is used as an active energy ray by irradiating KrF excimer laser, ArF excimer laser, F ₂ excimer laser, electron beam, X-ray, and EUV. A photoacid generator which decomposes with high efficiency and produces an acid of suitable acid strength is useful. Further, since it has a guanamine structure in the anion portion, it has an effect of reducing the acid diffusion length. Therefore, when used as a photoacid generator of a resist composition, it is excellent in the resolution at the time of lithography, and has the effect which can reduce LWR (Line width roughness) in a fine pattern.

In several aspects of the present invention, it is not limited to water development using an alkaline developer, water development using a neutral developer, or organic solvent development using an organic solvent developer, or the like.

The onium salt compound may be added to the resist composition as a low molecular weight component, or may be a polymer contained as a unit. In other words, the onium salt compound represented by the above formula (1) may be contained in the polymer as a unit in such a manner that it is bonded to the polymer main chain at any position of the compound. For example, in the case of the onium salt compound represented by the above formula (1), it is preferred to have an atomic bond bonded to the polymer backbone directly or via a linking group instead of one of R ¹ and R ² . The unit constituting the polymer is preferably a unit derived from a monomer having a radical polymerizable group such as a vinyl group, an isopropenyl group, an acryloxy group, or a methacryloxy group. The polymer may be a polymer containing a unit other than the unit corresponding to the onium salt compound. This will be explained in detail below.

When the onium salt compound is a polymer, the preferred number of carbon atoms of the above R ¹ and R ² in the formula (1) does not include the number of carbon atoms in the polymer main chain.

<1-4> Method for producing sulfonium salt compound

The onium salt compound of one aspect of the present invention can be produced by a method for producing an onium salt compound comprising the step of salt-exchange a compound represented by the following formula (2) with an ionic compound M ⁺ X ^- to obtain the above formula. (1) An onium salt compound represented.

(2) In the above formula, R ^1, R ^2, and R L is selected from the above-described formula (1) is ^1, R ² and L are the same selectable items.

Q ⁺ in the above formula (2) is a monovalent cation other than M ^{+ of the} above formula (1).

The above-described formula (2) M ⁺ X ^- M ⁺ and M in the formula (1) ⁺ the same, X is a monovalent anion.

The above Q ⁺ is preferably an ammonium cation represented by the following formula (3).

In the above formula (3), R ³ to R ⁶ are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of R ³ to R ⁶ is not a hydrogen atom.

When R ³ to R ⁶ have a methylene group, at least one methylene group of the above R ³ to R ⁶ may be substituted with a divalent hetero atom-containing group.

Two of the above R ³ to R ⁶ may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be selected from an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group, and At least any of the carbonyl groups together with the nitrogen atom to which they are bonded form a ring structure.

R ³ to R ⁶ in the above formula (3) are selected from the same optional items as R ¹ and R ² in the above formula (1).

The method of salt-exchange of the compound represented by the above formula (2) with the ionic compound M ⁺ X ^- is not particularly limited, and it can be carried out under ordinary conditions. For example, the sulfonium salt compound represented by the above formula (1) can be obtained from the organic layer by adding the ionic compound M ⁺ X ^{- to} the compound represented by the above formula (2) in an aqueous solvent and stirring the salt to carry out salt exchange. The above organic solvent used for salt exchange may be any solvent which is usually used for salt exchange. Examples of the organic solvent include a halogen solvent, an ester solvent, a ketone solvent, an ether solvent, and an aromatic solvent. Further, these solvents may be arbitrarily combined.

The above compound (2) can be produced, for example, by the following method.

Incidentally, in the following Synthesis Examples of R ¹ and R ² correspond to R (1) R ¹ and formula ² above.

The compound (2) can be produced, for example, by any one of the following formulas (A1) to (A3).

In the following formula (A1), a cyclic amine anhydride (4) is reacted with a primary or secondary amine to form a guanamine bond, and the cyclic acid anhydride (4) is opened to form an onium salt compound (2a). Thereafter, the onium salt compound (2a) is subjected to salt exchange with the ionic compound M ⁺ X ^- to obtain the onium salt compound (1).

At this time, an ammonium cation derived from a primary or secondary amine is produced, and an ammonium cation (N ⁺ H ₂ (R ¹ ) (R ² )) of the onium salt (2a) corresponds to a counter cation of the compound represented by the above formula (2) (Q ⁺ ).

Incidentally, the hydrogen atom on the nitrogen of the ammonium cation in the onium salt compound (2a) is derived from the above primary or secondary amine.

【化13】

On the other hand, in the following formula (A2), a ring-opening reaction is carried out in the presence of a primary or secondary amine and a tertiary amine in the above formula (A1) to form an ammonium cation derived from the tertiary amine, and a source. An ammonium cation of a primary or secondary amine. The ammonium cation (N ⁺ H(R ¹⁰¹ )(R ¹⁰² )(R ¹⁰³ ))) of the onium salt compound (2b) corresponds to the counter cation (Q ⁺ ) of the compound represented by the above formula (2). Each substituent of the ammonium cation in the following onium salt compound (2b) is derived from a substituent of an amine used as a raw material. Specifically, the following situations exist.

‧ R ¹⁰¹ and R ^{102 are} derived from R ¹ and R ^{2 of the} above primary or secondary amine, and R ^{103 is} derived from a hydrogen atom of the above primary or secondary amine (also referred to as "ammonium cation Qb1").

‧R ¹⁰¹ to R ^{103 are} derived from R ⁷ to R ⁹ (also referred to as "ammonium cation Qb2") of the above tertiary amine.

‧ mixing of the above ammonium cation Qb1 with the above ammonium cation Qb2.

Incidentally, the hydrogen atom on the nitrogen of the ammonium cation in the onium salt compound (2b) is derived from the above primary or secondary amine.

Thereafter, the onium salt compound (2b) is subjected to salt exchange with the ionic compound M ⁺ X ^- to obtain the onium salt compound (1).

In the formula (A2), when the primary or secondary amine (NH(R ¹ )(R ² )) is more hydrophobic than the tertiary amine (NH(R ⁷ )(R ⁸ )(R ⁹ )), the above formula ( 2) The counter cation (Q ⁺ ) of the compound represented is a tendency of the ammonium cation Qb1.

When the tertiary amine (N(R ⁷ )(R ⁸ )(R ⁹ )) is more hydrophobic than the primary or secondary amine (NH(R ¹ )(R ² )), the compound represented by the above formula (2) The counter cation (Q ⁺ ) is a trend of the ammonium cation Qb2.

In the formula (A2), when the primary or secondary amine (NH(R ¹ )(R ² )) and the tertiary amine (NH(R ⁷ )(R ⁸ )(R ⁹ )) have the same degree of hydrophobicity, the above formula The counter cation (Q ⁺ ) of the compound represented by (2) is a tendency of mixing of the ammonium cation Qb1 and the ammonium cation Qb2.

If the following formula (A3), the quaternary ammonium salt by ^{(N + (R 3) (} R 4) (R 5) (R 6) Y -) acting obtained by the above formula (A1) salt The compound (2a) or the onium salt compound (2b) obtained by the above formula (A2) is subjected to salt exchange to be induced into another onium salt compound (2c). Thereafter, the onium salt compound (2c) is further subjected to salt exchange with the ionic compound M ⁺ X ^- to obtain the onium salt compound (1).

<1-5> Photoacid generator

Several aspects of the invention are photoacid generators containing the above sulfonium salt compounds.

Further, when the resist composition contains the above-mentioned onium salt compound together with another photoacid generator, if the anion of the onium salt compound is an anion having an acid strength equal to or higher than that of the other photoacid generator, It is preferable because it functions as a photodecomposable base.

More specifically, the photoacid generator in several aspects of the invention preferably has a pKa of from -2 to 6. pKa is a value obtained by analysis using ACD labs (manufactured by Fujitsu Co., Ltd.).

As described above, the onium salt compound in several aspects of the invention may be a polymer. When the onium salt compound is a polymer, the polymer may be a homopolymer or a copolymer containing another unit as long as it contains a unit functioning as a photoacid generator. In the case of a copolymer, examples of the other unit include a unit that functions as an acid-reactive compound, a unit that contains a hydroxyaryl group, and the like. The unit that functions as the acid-reactive compound, the unit containing a hydroxyaryl group, and the like will be described below.

<2> Resist composition

One aspect of the invention relates to a resist composition comprising a photoacid generator in several aspects of the invention. The above resist composition preferably further contains the above photoacid generator and acid reactive compound.

Further, the resist composition may contain a second photoacid generator in addition to the photoacid generator (hereinafter referred to as "first photoacid generator") in several aspects of the present invention. When the pKa of the second photo-generating agent is smaller than that of the first photo-acid generator, the first photo-acid generator acts as a photodegradable base, which is preferable.

The content of the first photo-acid generator in the resist composition according to the aspect of the invention is preferably 0.5 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the acid-reactive compound to be described later. More preferably, it is 2-10 mass parts.

Further, when the first photoacid generator is used as a photodecomposable base, that is, when the second photoacid generator is contained in the resist composition, the content of the first photoacid generator in the resist composition is It is preferably 1 to 100 parts by mass, and more preferably 3 to 75 parts by mass, per 100 parts by mass of the second photoacid generator. By including the first photoacid generator in the above range in the resist composition, it is possible to have characteristics excellent in sensitivity, resolution, and pattern forming ability.

When the content is calculated, the organic solvent is not included in the composition of the resist composition.

Further, when the first photoacid generator and the second photoacid generator are bonded to a polymer, the mass of the portion other than the polymer main chain is used as a reference.

In addition, the above-mentioned first photoacid generator may be used alone or in combination of two or more.

Hereinafter, each component contained in the resist composition will be described.

<2-1> 2nd photoacid generator

The resist composition of several aspects of the invention preferably contains a second photoacid generator.

The photo-acid generator which is generally used for the resist composition is not particularly limited, and examples thereof include an onium salt compound such as a phosphonium salt or an iodonium salt, and N-sulfonyloxy anthracene. An imine compound, an oxime sulfonate compound, an organohalogen compound, a sulfonyldiazomethane compound, or the like. These may be used alone or in combination of two or more.

Examples of the onium salt include the onium salt described in WO2011/093139.

As described above, the anion of the second photoacid generator is preferably an anion having a higher acid strength than the anion of the onium salt compound of the first photoacid generator.

More specifically, the second photoacid generator preferably has a pKa of -3 or less. Examples of such an anion include a fluorine atom-substituted sulfonic acid and the like.

The second photoacid generator may be added to the resist composition as a low molecular weight component, or may be contained as a unit of the polymer. In other words, it may be a form in which a unit of the second photoacid generator is bonded to the polymer main chain as a unit in the polymer. For example, when the second photoacid generator is a phosphonium salt, it is preferred that the polymer main chain directly has an atomic bond or an atomic bond bonded via a linking group instead of one H in the substituent in the onium salt.

The content of the second photoacid generator in the resist composition according to the aspect of the invention is preferably 1 to 50 parts by mass, more preferably 3 to 30 parts by mass, more preferably 3 to 30 parts by mass, more preferably 100 parts by mass of the acid-reactive compound described later. 5 to 25 parts by mass.

When the second photoacid generator is bonded to a polymer, the mass of the portion other than the polymer main chain is used as a reference.

<2-2> Acid-reactive compound

The resist composition of some aspects of the present invention preferably further contains an acid-reactive compound in addition to the second photo-acid generator.

The acid-reactive compound preferably has a protective group deprotected by an acid, polymerized by acid, or crosslinked by an acid. That is, the acid-reactive compound is preferably at least one selected from the group consisting of a compound having a protective group deprotected by an acid, a compound having a polymerizable group polymerized by an acid, and a crosslinking agent having a cross-linking action due to an acid. Either.

The compound having a protective group deprotected by acid refers to a compound in which the protective group is deprotected by an acid to form a polar group and the solubility in the developer is changed. For example, in the case of water development using an alkaline developer or the like, the compound having a protective group deprotected by an acid is a compound which is insoluble with respect to an alkaline developer, but which is produced by exposure of the above photoacid generator. Under the action of an acid, the protective group is deprotected from the above compound in the exposed portion and becomes soluble with respect to the alkaline developing solution.

In some aspects of the invention, it is not limited to an alkaline developer, and may be a neutral developer or an organic solvent solution. Therefore, when an organic solvent developing solution is used, the compound having a protective group deprotected by an acid is a compound which is protected from the above-mentioned compound at the exposed portion by exposure of an acid generated by the above photoacid generator. Deprotection produces a polar group and the solubility in an organic solvent developer is lowered.

The polar group of the acid-reactive compound may, for example, be a hydroxyl group, a carboxyl group, an amino group or a sulfonic acid group.

The protecting group deprotected by acid is a group which protects the hydrogen atom of the above polar group with a protecting group. Specific examples of the protective group include a tertiary alkyl ester group, an acetal group, a tetrahydropyranyl group, a carbonate group, a decyloxy group, and a benzyloxy group. As the compound having such a protective group, a compound having a styrene skeleton, a methacrylate or an acrylate skeleton in which these protective groups are suspended is preferably used.

The compound having a protective group deprotected by acid may be a low molecular compound containing a protective group or a polymer containing a protective group. In several aspects of the invention, the low molecular compound is a compound having a weight average molecular weight (weight average molecular weight) of less than 2,000, and the polymer is a compound having a weight average molecular weight of 2,000 or more.

The compound having a polymerizable group polymerized by an acid is a compound which is polymerized by the action of an acid to change the solubility of the developer. For example, in the case of water system development, it acts on a compound which is soluble in an aqueous developing solution, and the solubility of the compound in the aqueous developing solution is lowered after polymerization. Specific examples thereof include compounds having an ethoxy group, a vinyloxy group, and an oxetanyl group.

The compound having a polymerizable group polymerized by an acid may be a polymerizable low molecular compound or a polymerizable polymer.

The cross-linking agent having a cross-linking action due to an acid means a compound which undergoes cross-linking under the action of an acid to change the solubility in a developing solution. For example, in the case of water-based development, the compound which is soluble in the aqueous developing solution is polymerized or crosslinked, and the solubility of the compound with respect to the aqueous developing solution is lowered. Specific examples thereof include a crosslinking agent having an ethoxy group, a vinyloxy group, a 1-alkoxyamino group, and an oxetanyl group. When the compound is a crosslinking agent having a crosslinking action, a compound which is a target of crosslinking, that is, a compound which reacts with a crosslinking agent and changes solubility in a developing solution, may be a compound having a phenolic hydroxyl group.

The compound having a cross-linking action due to an acid may be a polymerizable low molecular compound or a polymerizable polymer.

When the acid-reactive compound is a polymer, the polymer may contain other units generally used in the resist composition in addition to the unit in which the reactive compound is bonded. The other unit may, for example, be a unit (I) having at least any one selected from the group consisting of a lactone site, a sultone site, and a decylamine site; and having a structure selected from the group consisting of an ether bond, an ester bond, and an acetal structure. a unit (II) of at least any one of a group and a hydroxyl group; a unit (III) having a hydroxyaryl group, and the like. Further, a unit (V) in which the first photoacid generator is bonded and a unit (V) in which the second photoacid generator is bonded may be further contained.

In some embodiments of the present invention, the ratio of each unit of the polymer is not particularly limited, and when the unit in which the acid reactive compound is bonded and another unit are used as a unit of the same polymer, the acid reactive compound is bonded. The unit is preferably 10 to 70% by mole, more preferably 15 to 65% by mole, still more preferably 20 to 60% by mole based on the total polymer unit.

The above unit (I) is preferably 0 to 60% by mole, more preferably 10 to 60% by mole, still more preferably 20 to 60% by mole based on the whole. The unit (II) is preferably 0 to 70% by mole, more preferably 5 to 70% by mole, still more preferably 10 to 60% by mole. The above unit (III) is preferably 0 to 90% by mole, and more preferably 10 to 80% by mole based on the whole. The unit (IV) is preferably 0 to 30% by mole, more preferably 1 to 30% by mole, still more preferably 3 to 20% by mole. The unit (V) is preferably 0 to 30% by mole, more preferably 1 to 30% by mole, still more preferably 3 to 20% by mole.

<2-3>Other ingredients

In the resist composition of one aspect of the present invention, in addition to the above components, an organic solvent, an acid diffusion controlling agent, a surfactant, an organic carboxylic acid, and a dissolution inhibitor which are used in a usual resist composition may be combined as needed. Agents, stabilizers, pigments, sensitizers and the like are optional components.

As the organic solvent, for example, ethylene glycol monoethyl ether acetate, cyclohexanone, 2-heptanone, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether C is preferable. Acid ester, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl β-methoxyisobutyrate, ethyl butyrate, propyl butyrate , methyl isobutyl ketone, ethyl acetate, isoamyl acetate, ethyl lactate, toluene, xylene, cyclohexyl acetate, diacetone alcohol, N-methylpyrrolidone, N,N-dimethylformamidine Amine, γ-butyrolactone, N,N-dimethylacetamide, propylene carbonate, ethylene carbonate, and the like. These organic solvents may be used singly or in combination.

The above acid diffusion controlling agent has an effect of controlling the diffusion phenomenon of an acid generated by the photoacid generator in the resist film and controlling an unfavorable chemical reaction in the non-exposed region. Therefore, the storage stability of the obtained resist composition is improved, and the resolution of the resist is further improved, and the line width of the resist pattern due to the variation of the interval time from exposure to development processing can be suppressed. The change was carried out to obtain a resist composition excellent in process stability.

The acid diffusion controlling agent may, for example, be a compound having one, two or three nitrogen atoms in the same molecule, a guanamine group-containing compound, a urea compound or a nitrogen-containing heterocyclic compound. Further, as the acid diffusion controlling agent, the photodegradable base other than the above-described onium salt compound which is one of the aspects of the present invention which is lightly generated by exposure and which produces a weak acid can also be used. Specific examples include Japanese Patent No. 3357743, Japanese Patent Laid-Open No. 2001-215689, Japanese Patent Laid-Open No. 2001-166476, Japanese Patent Laid-Open No. 2008-102383, Japanese Patent Application No. 2010-243773, Japanese Patent Application No. 2011-37835, and Japan. The compound described in JP-A-2012-173505.

The content of the acid-containing diffusion controlling agent is preferably 0.01 to 20 parts by mass, more preferably 0.03 to 15 parts by mass, even more preferably 0.05 to 10 parts by mass, per 100 parts by mass of the acid-reactive compound. The first photoacid generator of one aspect of the present invention is not included in the above content.

The above surfactant is preferably used for improving coatability. Examples of the surfactant include polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters, and polycondensation. A nonionic surfactant such as an oxyethylene sorbitan fatty acid ester, a fluorine-based surfactant, or an organic siloxane polymer.

The content of the surfactant is preferably 0.0001 to 2 parts by mass, more preferably 0.0005 to 1 part by mass, per 100 parts by mass of the acid-reactive compound.

Examples of the organic carboxylic acid include an aliphatic carboxylic acid, an alicyclic carboxylic acid, an unsaturated aliphatic carboxylic acid, a hydroxycarboxylic acid, an alkoxycarboxylic acid, a ketocarboxylic acid, a benzoic acid derivative, and a phthalic acid. , terephthalic acid, isophthalic acid, 2-naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, and the like. Since the organic carboxylic acid is volatilized from the surface of the resist film to contaminate the drawing chamber when electron beam exposure is performed by vacuuming, a preferred organic carboxylic acid is an aromatic organic carboxylic acid, and suitable examples thereof include benzoic acid. , 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid.

The content of the organic carboxylic acid is preferably 0.01 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, even more preferably 0.01 to 3 parts by mass, per 100 parts by mass of the acid-reactive compound.

The resist composition component is dissolved in the organic solvent, and is preferably dissolved at 1 to 40% by mass, more preferably 1 to 30% by mass, even more preferably 3 to 20% by mass, as the solid content concentration.

When the resist composition of one aspect of the present invention contains a polymer, the polymer preferably has a weight average molecular weight of from 2,000 to 200,000, more preferably from 2,000 to 50,000, still more preferably from 2,000 to 15,000. The preferred dispersion (molecular weight distribution) (Mw/Mn) of the above polymer is from 1.0 to 1.7, and more preferably from 1.0 to 1.2, from the viewpoint of sensitivity.

In several aspects of the invention, the weight average molecular weight and dispersion of the polymer are defined as polystyrene-converted values based on GPC measurements.

The resist composition of one aspect of the present invention may contain a fluorine-containing water-repellent polymer.

The fluorine-containing water-repellent polymer is not particularly limited, and examples thereof include a polymer which is usually used in a liquid immersion exposure process, and a polymer having a fluorine-containing chlorine larger than the above polymer is preferable. Thus, when the resist film is formed using the resist composition, the water repellency of the fluorine-containing water-repellent polymer can bias the fluorine-containing water-repellent polymer on the surface of the resist film.

The fluorine content of the fluorine-containing water-repellent polymer is preferably 25% or more of the hydrogen atom of the hydrocarbon group in the fluorine-containing water-repellent polymer, and more preferably 50% or more.

As the content of the fluorine-containing water-repellent polymer in the resist composition, the above polymer (not the fluorine-containing water-repellent polymer) with respect to one aspect of the present invention is considered from the viewpoint of improving the hydrophobicity of the resist film. 100 parts by mass is preferably 0.5 to 10 parts by mass. The fluorine-containing water-repellent polymer may be used singly or in combination of two or more.

The composition of one aspect of the present invention can be obtained by mixing the components of the above composition, and the mixing method is not particularly limited.

<3> Method of manufacturing equipment

One aspect of the present invention provides a method of manufacturing a device comprising: forming a resist film by applying the resist composition onto a substrate or the like; and exposing the resist film; and The step of developing the exposed resist film.

One aspect of the present invention may be a method of producing a patterned substrate before singulation of a wafer, comprising: a step of forming a resist film using the above resist composition; and a step of exposing the resist film; And a step of developing the exposed resist film.

The active energy ray used for the exposure in the step of exposing the resist film may be any one that can activate the sulfonium salt compound of one aspect of the present invention to generate an acid, and means KrF excimer laser or ArF Molecular laser, F ₂ excimer laser, electron beam, UV, visible light, X-ray, electron beam, ion beam, i-ray, EUV, etc.

In one aspect of the invention, as the active energy ray for exposure for the photolithography step, an electron beam (EB) or an extreme ultraviolet ray (EUV) or the like is preferable.

The amount of light to be irradiated varies depending on the type and mixing ratio of each component in the photocurable composition, the thickness of the coating film, and the like, and is preferably 1 J/cm ² or less or 1000 μC/cm ² or less.

When the resist composition contains the sensitizing compound or contains the corresponding sensitizing compound as a sensitizing unit in the polymer, it is also preferred to perform the second exposure with ultraviolet rays or the like after irradiating the active energy ray.

 [Examples]  

Several aspects of the invention are described below based on the examples, but the invention is not limited by these examples.

[Synthesis of strontium salt 1 (A-1)]

Synthesis of ‧4-(cyclohexylaminocarbonyl)-2,2,3,3,4,4-hexafluorobutyric acid-cyclohexylammonium salt

Hexafluoroglutaric anhydride (25.4 g) was dissolved in dichloromethane (264 g) and cooled to 5 °C. Then, a dichloromethane solution (62 g) containing cyclohexylamine (29.0 g) was added dropwise, and the mixture was added dropwise at 5 ° C for 24 hours. After confirming the completion of the reaction, acetic acid (3.5 g) and methanol (51 g) were added, and washed three times with pure water (30 g). The organic layer was separated and dried under reduced pressure to give the title compound (29.3 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 8.31 (brd, 3H), 7.81 (brd, 1H), 3.73-3.71 (m, 1H), 3.08-3.00 (m, 1H), 2.03-1.64 (m, 10H), 1.43-1.15 (m, 10H). ¹⁹ F-NMR (400MHz, DMSO-d6) δ -112.0 (t, 2F), -114.9 (t, 2F), -122.1 (m, 2F).

Synthesis of ‧4-(cyclohexylaminocarbonyl)-2,2,3,3,4,4-hexafluorobutyric acid-triphenylphosphonium salt

Pure water (88 g) and methylsulfate-triphenylsulfonium salt (15.0 g) and dichloromethane (88 g) were added to the above ammonium salt (9.8 g), and stirred at room temperature for 2 hours. The organic layer was separated and washed 5 times with purified water (44 g). After the organic layer was separated from the reaction mixture, the solvent was evaporated, and then evaporated to yield the desired compound (12.2 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 8.31 (brs, 1H), 7.95-7.83 (m, 15H), 3.68-3.64 (m, 1H), 1.93-1.53 (m, 5H), 1.44-1.12 ( m,5H). ¹⁹ F-NMR (400MHz, DMSO-d6) δ -111.9 (t, 2F), -114.7 (t, 2F), -122.0 (m, 2F).

[Synthesis of strontium salt 2 (A-2)]

Synthesis of ‧4-(1-adamantylaminocarbonyl)-2,2,3,3,4,4-hexafluorobutyrate-1-adamantane ammonium salt

Hexafluoroglutaric anhydride (19.0 g) was dissolved in dichloromethane (160 g) and cooled to 5 °C. Then, a dichloromethane solution (70 g) containing 1-aminoadamantane (33.7 g) was added dropwise, and the mixture was stirred at 5 ° C for 48 hours. After confirming the completion of the reaction, acetic acid (2.3 g) was added, and the mixture was washed 5 times with pure water (80 g). After the organic layer was separated, dried under reduced pressure to give the title compound (1. The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 8.34 (brs, 3H), 3.77-3.74 (m, 1H), 2.30-1.67 (m, 30H) 19 F-NMR (400MHz, DMSO-d6) δ. - 112.2 (t, 2F), -114.6 (t, 2F), -122.5 (m, 2F).

Synthesis of ‧4-(1-adamantylaminocarbonyl)-2,2,3,3,4,4-hexafluorobutyric acid-triphenylphosphonium salt

Pure water (30 g) and methylsulfate-triphenylsulfonium salt (6.3 g) and dichloromethane (99 g) were added to the above ammonium salt (8.0 g), and stirred at room temperature for 2 hours. The organic layer was separated and washed 5 times with pure water (41 g). After the organic layer was separated from the reaction mixture, the solvent was evaporated and evaporated to yield the desired product (9.0 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 8.28 (brs, 1H), 7.82-7.64 (m, 15H), 2.28-1.63 (m, 15H) 19 F-NMR (400MHz, DMSO-d6) δ. - 112.1(t, 2F), -114.5(t, 2F), -122.5(m, 2F).

[Synthesis of strontium salt 3 (A-3)]

【化18】

Synthesis of ‧3-(4-morpholinocarbonyl)-2,2,3,3-tetrafluoropropionic acid-morpholinium salt

Tetrafluorosuccinic anhydride (4.2 g) was dissolved in dichloromethane (46 g) and cooled to 5 °C. Then, a dichloromethane solution (16 g) containing morpholine (5.5 g) was added dropwise, and the mixture was stirred at 5 ° C for 24 hours. After confirming the completion of the reaction, acetic acid (0.6 g) was added, and the mixture was washed 5 times with pure water (20 g). After the organic layer was separated, the mixture was dried under reduced pressure to give the title compound (3.1 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 6.68 (brs, 2H), 3.95-3.68 (m, 16H) 19 F-NMR (400MHz, DMSO-d6) δ -108.8 (t, 2F), -. 113.5 (t, 2F).

Synthesis of ‧3-(4-morpholinocarbonyl)-2,2,3,3-tetrafluoropropionic acid-triphenylphosphonium salt

Pure water (19 g) and triphenylsulfonium-methyl sulfate (10 g) and dichloromethane (59 g) were added to the ammonium salt (3.1 g), and stirred at room temperature for 2 hours. The organic layer was separated and washed 5 times with pure water (19 g). After the organic layer was separated from the reaction mixture, the solvent was evaporated and evaporated to yield to the desired product (11.0 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 7.91-7.79 (m, 15H), 3.69-3.58 (m, 8H). 19 F-NMR (400MHz, DMSO-d6) δ -108.6 (t, 2F), -113.4 (t, 2F).

[Synthesis of strontium salt 4 (A-4)]

Synthesis of ‧4-[(1-ethoxycarbonyl)piperazinecarbonyl]-2,2,3,3,4,4-hexafluorobutanoic acid-1-ethoxycarbonylpiperazinium salt

1-Ethoxycarbonylpyridazine (8.9 g) was dissolved in dichloromethane (40 g) and cooled to 5 °C. Then, a dichloromethane solution (29 g) containing hexafluoroglutaric anhydride (5.0 g) was added dropwise, and the mixture was stirred at 5 ° C for 24 hours. After confirming completion of the reaction, acetic acid (0.7 g) was added, and the mixture was washed 5 times with pure water (30 g). After the organic layer was separated, the mixture was dried under reduced pressure to give the title compound (6.1 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

¹ H-NMR (400 MHz, DMSO-d6) δ 6.68 (brs, 2H), 4.05 (q, 4H), 3.94 - 3.24 (m, 16H), 1.18 (t, 6H). ¹⁹ F-NMR (400 MHz, DMSO -d6) δ -112.0 (t, 2F), -114.8 (t, 2F), -122.2 (m, 2F).

Synthesis of ‧4-[(1-ethoxycarbonyl)piperazinecarbonyl]-2,2,3,3,4,4-hexafluorobutyric acid-triphenylphosphonium salt

Pure water (88 g) and triphenylsulfonium methylsulfate salt (4.5 g) and dichloromethane (63 g) were added to the above ammonium salt (5.4 g), and stirred at room temperature for 2 hours. The organic layer was separated and washed 5 times with pure water (25 g). After the organic layer was separated from the reaction mixture, the solvent was evaporated and evaporated to give the title compound (5.5 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 7.91-7.79 (m, 15H), 4.11 (q, 2H), 3.88-3.39 (m, 4H), 2.95-2.91 (m, 4H), 1.17 (t, 3H). ¹⁹ F-NMR (400MHz, DMSO-d6) δ -111.7 (t, 2F), -114.6 (t, 2F), -122.1 (m, 2F).

[Synthesis of strontium salt 5]

Synthesis of ‧4-(phenylaminocarbonyl)-2,2,3,3,4,4-hexafluorobutyric acid-anilinium salt

Hexafluoroglutaric anhydride (2.7 g) was dissolved in dichloromethane (25 g) and cooled to 5 °C. Then, a dichloromethane solution (8.0 g) containing aniline (3.0 g) was added dropwise, and the mixture was stirred at 5 ° C for 24 hours. After confirming the completion of the reaction, acetic acid (0.6 g) was added, and the mixture was washed 5 times with pure water (15 g). After the organic layer was separated, the mixture was dried under reduced pressure to give the title compound (4.5 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

¹ H-NMR (400 MHz, CDCl ₃ ) δ 7.21. (t, 4H), 7.06 (brs, 3H), 6.92 - 6.86 (m, 6H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ -112.5 (t , 2F), -114.5 (t, 2F), -123.4 (m, 2F).

Synthesis of ‧4-(phenylaminocarbonyl)-2,2,3,3,4,4-hexafluorobutyric acid-triphenylphosphonium salt

Pure water (22 g) and triphenylsulfonium methylsulfate (5.0 g) and dichloromethane (38 g) were added to the above ammonium salt (4.4 g), and stirred at room temperature for 2 hr. The organic layer was separated and washed 5 times with pure water (15 g). After the organic layer was separated from the reaction mixture, the solvent was evaporated, and then evaporated to yield to afford the desired product (5.5 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, CDCl} 3) δ 7.78-7.67 (m, 15H), 7.11 (t, 2H), 6.92 (brs, 1H), 6.73-6.66 (m, 3H). 19 F-NMR (400MHz, DMSO-d6) δ -112.4 (t, 2F), -114.4 (t, 2F), -123.2 (m, 2F).

[Synthesis of strontium salt 6]

Synthesis of ‧3-(N-Dicyclohexylaminocarbonyl)-2,2,3,3-tetrafluoropropionic acid-dicyclohexylammonium salt

Hexafluoroglutaric anhydride (3.1 g) was dissolved in dichloromethane (46 g) and cooled to 5 °C. Then, a dichloromethane solution (20 g) containing cyclohexylamine (8.4 g) was added dropwise, and the mixture was stirred at 5 ° C for 24 hours. After confirming completion of the reaction, the organic layer was washed with pure water (28 g) for 5 times, and then the organic layer was separated, and the solvent was evaporated to yield to afford the desired compound (5.1 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

¹ H-NMR (400 MHz, acetone-d6) δ 10.40 (brs, 2H), 3.83-3.67 (m, 2H), 3.31 (m, 2H), 1.94-1.11 (m, 40H). ¹⁹ F-NMR (400 MHz) , DMSO-d6) δ -109.0 (t, 2F), -113.8 (t, 2F).

Synthesis of ‧3-(N-Dicyclohexylaminocarbonyl)-2,2,3,3-tetrafluoropropionic acid-triphenylphosphonium salt

Pure water (30 g) and triphenylsulfonium methylsulfate salt (4.9 g) and dichloromethane (45 g) were added to the ammonium salt (5.1 g), and stirred at room temperature for 2 hours. The organic layer was separated and washed 5 times with pure water (30 g). After separating the oil layer from the reaction mixture, the solvent was evaporated on a rotary evaporator to give the title compound (6.3 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

¹ H-NMR (400 MHz, acetone-d6) δ 7.99-7.82 (m, 15H), δ 3.80-3.65 (m, 2H), 1.94-1.11 (m, 20H). ¹⁹ F-NMR (400 MHz, DMSO-d6) ) δ -108.9 (t, 2F), -113.6 (t, 2F).

[Synthesis of strontium salt 7]

Synthesis of ‧3-(N-ethylaminocarbonyl)-2,2,3,3-tetrafluoropropionic acid-tetrabutylammonium salt

Hexafluoroglutaric anhydride (5.6 g) was dissolved in dichloromethane (35 g) and cooled to 5 °C. Then, a THF solution (30 g) of diethylamine was added dropwise, and the mixture was stirred at 5 ° C for 24 hours. After confirming completion of the reaction, dichloromethane (75 g), tetrabutylammonium chloride (20 g), and pure water (45 g) were added, and the mixture was warmed to room temperature and stirred for 2 hours. The organic layer was separated from the reaction mixture and washed 5 times with purified water (35 g). Thereafter, the organic layer was separated, and the solvent was evaporated from the rotary evaporator to yield the object (9.4 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, CDCl3} ) δ 9.05 (brs, 1H), 3.94-3.87 (q, 2H), 3.448 (t, 8H), 1.74 (m, 8H), 1.48 (m, 8H), 1.33 (t , 3H), 1.00 (t, 12H). ¹⁹ F-NMR (400MHz, DMSO-d6) δ -112.1 (t, 2F), -114.8 (t, 2F), -122.3 (m, 2F).

Synthesis of triphenylphosphonium 3-(N-ethylaminocarbonyl)-2,2,3,3-tetrafluoropropionate

To the ammonium salt (4.5 g), pure water (23 g) and a methylsulfate-triphenylsulfonium salt (3.5 g) and dichloromethane (45 g) were added, and the mixture was stirred at room temperature for 2 hours. The organic layer was separated and washed 5 times with pure water (23 g). After separating the organic layer from the reaction mixture, the solvent was evaporated and evaporated to yield to the desired product (4.2 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, CDCl3} ) δ 9.05 (brs, 1H), 7.93-7.81 (m, 15H) 3.94-3.87 (q, 2H), 1.00 (t, 3H). 19 F-NMR (400MHz, DMSO- D6) δ -111.9 (t, 2F), -114.7 (t, 2F), -122.0 (m, 2F).

[Synthesis of strontium salt 8 (A-5)]

Synthesis of ‧4-(1-adamantyloxycarbonyl)-2,2,3,3,4,4-hexafluorobutyric acid-triphenylphosphonium salt

1-adamantanol (5.8 g), pyridine (3.2 g) and dichloromethane (60 g) were combined and cooled to 5 °C. Then, a dichloromethane solution (20 g) containing hexafluoroglutaric anhydride (9.4 g) was added dropwise, and the mixture was stirred at 5 ° C for 1 hour. Thereafter, the reaction mixture was warmed to reflux with heating and stirred for additional 48 hours. After the reaction mixture was cooled to room temperature, pure water (110 g) was added and stirred for 30 minutes. The organic layer was separated and washed 5 times with pure water (64 g). The organic layer was separated, pure water (64 g) was added, and the methyl sulphate-triphenyl sulfonium salt (17.5 g) was added, and the mixture was stirred at room temperature for 2 hours. The organic layer was separated, washed three times with a 10% aqueous sodium carbonate solution (64 g), and washed five times with purified water (64 g). The organic layer was separated and the solvent was evaporated using a rotary evaporator. The obtained crude product was purified by silica gel column chromatography to give the title compound (9.2 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, DMSO} -d6) δ 7.93-7.77 (m, 15H), 2.10-1.63 (m, 15H). 19 F-NMR (400MHz, DMSO-d6) δ -113.2 (t, 2F), -114.9 (t, 2F), -121.4 (m, 2F)

[Synthesis of strontium salt 9 (A-6)]

‧ Synthesis of heptafluorobutyric acid-triphenylsulfonium salt

A 10% aqueous sodium carbonate solution (85 g) was cooled to 5 ° C, and heptafluorobutyric acid (15.0 g) was added dropwise thereto over 20 minutes, and the mixture was stirred for 30 minutes to prepare an aqueous solution of sodium heptafluorobutyrate. Dichloromethane (330 g) and methylsulfate-triphenylsulfonium salt (29.0 g) were added thereto, and the mixture was stirred at room temperature for 4 hours. The organic layer was separated, and the organic layer was washed 5 times with purified water (33 g). The organic layer was separated, and the solvent was evaporated to dryness on a rotary evaporator to yield the object [R-2] (23.4 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

¹ H-NMR (400 MHz, DMSO-d6) δ 7.95-7.83 (m, 15H).

¹⁹ F-NMR (400 MHz, DMSO-d6) δ -78.1 (t, 3H), -115.6 (t, 2H), -119.0 (m, 2H).

[Synthesis of strontium salt 10 (A-9)]

【化25】

Synthesis of ‧4-(1-adamantylaminocarbonyl)butyric acid-triphenylphosphonium salt

Glutaric anhydride (12 g), 1-adamantamine (15.0 g), and DMAP (14 g) were added to toluene (100 g) and stirred, and the temperature was raised to reflux temperature. After 72 hours, the reaction mixture was cooled to room temperature, and the solvent was evaporated to give a crude product. Dichloromethane (55 g) and pure water (20 g) were added to the crude product, and stirred for 30 minutes. The organic layer was separated and washed 5 times with pure water (20 g). Methylsulfate-triphenylsulfonium salt (15 g) was added and stirred at room temperature for 2 hours. The organic layer was separated, washed three times with a 10% aqueous sodium carbonate solution (20 g), and washed twice with purified water (20 g). The organic layer was separated and the solvent was evaporated using a rotary evaporator. The obtained crude product was purified by silica gel column chromatography to give the title compound (12.9 g). The result of the NMR spectrum measurement confirmed that the substance was a target. The results are shown below.

^{1 H-NMR (400MHz, CDCl3} ) δ 7.82-7.66 (m, 15H), 6.86 (brs, 1H), 2.36-1.45 (m, 21H).

[Examples 1 to 5 and Comparative Examples 1 to 5]

[Preparation of photosensitive resin composition solution]

A positive resist composition was prepared by mixing and dissolving each component shown in Table 1 with respect to 100 parts by mass of the acid-reactive compound represented by the following formula (the abbreviations in the table have the following meanings). In addition, the numerical value in () is a mixing amount (parts by mass) with respect to 100 parts by mass of the high molecular weight body which is an acid-reactive compound. Incidentally, in the following examples and comparative examples, an acid-reactive compound having the following unit ratio (a: b: c) is used, but the present invention is not limited thereto.

Weight average molecular weight: about 9300

a=0.4, b=0.4, c=0.2

A-1 to A-9 are each a phosphonium salt represented by the following formula. Incidentally, A-1 to A-6 and A-9 are those obtained by the above synthesis. A-7 and A-8 can be synthesized by a known method.

B-1 and B-2 are each represented by the following formula. In addition, B-1 is synthesized by the method described in International Publication No. 2011/93139, and B-2 is synthesized by the method described in International Publication No. 2015/083264.

[Evaluation of Photosensitive Resin Composition Solution]

Each of the above resist compositions was spin-coated on a ruthenium sheet by a spin coater, and then prebaked on a hot plate at 110 ° C for 60 seconds to obtain a coating film having a film thickness of 150 nm. Using a mask, an ArF excimer laser stepper (wavelength: 193 nm) was used for exposure, and the PEB temperature was set to 110 ° C for 90 seconds to obtain a 90 nm line pattern. Thereafter, development was carried out for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide, followed by rinsing with pure water for 30 seconds to obtain a substrate on which a pattern was formed.

With respect to the sensitivity, the resolution, and the line width roughness (LWR) at this time, the sensitivity of Examples 1 to 5 and Comparative Examples 2 to 5 at the time of comparison with the reference was evaluated based on the values of Comparative Example 1 based on the following indexes. Degree, resolution, and performance of LWR. Incidentally, the length of the resist pattern was measured using a scanning electron microscope.

<indicator>

◎: Compared with Comparative Example 1, an increase of 10% or more was observed.

○: An increase of 5% or more and 10% or less was observed with respect to Comparative Example 1.

△: An increase of 0% or more and 5% or less was observed with respect to Comparative Example 1.

×: worse than Comparative Example 1

Sensitivity, resolution, and LWR evaluation projects are defined as follows.

(sensitivity)

Indicates the minimum exposure amount for reproducing a 90 nm line pattern. The smaller the minimum exposure, the better the sensitivity.

(resolution)

The width (nm) of the line pattern capable of being resolved by the minimum exposure amount for reproducing the 90 nm line pattern, that is, the limit resolution. The smaller the value, the better the resolution.

(Line width roughness: LWR)

The gate length of 50 points was measured in the range of 2.5 μm in the longitudinal direction of the 90 nm line pattern obtained by reproducing the minimum exposure amount of the 90 nm line pattern, and the standard deviation (σ) was obtained, and the value of 3 times was calculated (3σ) ) as LWR. The smaller the value, the smaller the roughness of the resulting pattern, and the better the performance.

The evaluation of the photosensitive resin composition solutions of Examples 1 to 5 and Comparative Examples 2 to 5 is shown in Table 2.

[Examples 6 to 7 and Comparative Examples 6 to 7]

The photosensitive resin composition solution was prepared in the same manner as in Example 1, and the mixing amount was adjusted so that the amount of the photodegradable alkali was equal to that of Example 1, and the evaluation was carried out.

With respect to the sensitivity, the resolution, and the LWR at this time, the sensitivity, the resolution, and the sensitivity and resolution of Examples 6 to 7 and Comparative Examples 6 to 7 when compared with the standard were evaluated based on the values of Comparative Example 6 based on the following indexes. The performance of LWR. Incidentally, the length of the resist pattern was measured using a scanning electron microscope.

<indicator>

◎: Compared with Comparative Example 6, an increase of 10% or more was observed.

○: An increase of 5% or more and 10% or less was observed with respect to Comparative Example 6.

△: With respect to Comparative Example 6, an upward of 0% or more and 5% or less was observed.

×: worse than Comparative Example 6

The evaluation results are shown in Table 4.

[Embodiment 8]

10.0 parts by mass of the photoacid generator A-1 synthesized above, 100 parts by mass of the high molecular weight body represented by the above structure, and 0.2 parts by mass of triethanolamine were dissolved in 525 parts by mass of propylene glycol monomethyl ether acetate, and sieved with PTFE. The program came over to prepare a photoresist composition solution. Next, the photoresist composition solution was spin-coated on a ruthenium sheet, and then prebaked on a hot plate at 110 ° C for 90 seconds to obtain a resist film having a film thickness of 300 nm. The film was exposed using an ArF excimer laser stepper (wavelength 193 nm), followed by baking at 130 ° C for 90 seconds. Thereafter, an aqueous solution of 2.38% of tetramethylammonium hydroxide was developed for 60 seconds, and rinsed with pure water for 30 seconds.

Regarding the resolution and the LWR (Line width roughness), the same evaluation as in Example 1 and the like was performed. In the example 8, the performance was evaluated by the following indexes based on the resolution and the value of LWR when the resist composition prepared in the following Comparative Example 9 was used. Incidentally, the length of the resist pattern was measured using a scanning electron microscope.

<indicator>

◎: Compared with Comparative Example 9, an increase of 10% or more was observed.

○: an increase of 5% or more and 10% or less was observed with respect to Comparative Example 9.

△: An increase of 0% or more and 5% or less was observed with respect to Comparative Example 9.

×: worse than Comparative Example 9

The structure is shown in Table 5.

[Embodiment 9]

Using 10.8 parts by mass of the photoacid generator A-2 obtained above in place of 10.0 parts by mass of the photoacid generator A-1, a resist composition was prepared in the same manner as in Example 8 to obtain a resist film, and after exposure, Baking and developing. In the same manner as in Example 8, the results of the use of the resist composition prepared in Comparative Example 9 and the value of LWR were used, and the results obtained are shown in Table 5.

[Comparative Example 8]

Using the 8.2 parts by mass of the photoacid generator A-6 obtained above in place of 10.0 parts by mass of the photoacid generator A-1, a resist composition was prepared in the same manner as in Example 8 to obtain a resist film, and after exposure, Baking and developing. In the same manner as in Example 8, the results of the use of the resist composition prepared in Comparative Example 9 and the value of LWR were used, and the results obtained are shown in Table 5.

[Comparative Example 9]

A resist composition was prepared in the same manner as in Example 8 except that 10.0 parts by mass of the photoacid generator A-5 obtained above was used instead of 10.0 parts by mass of the photoacid generator A1 to obtain a resist film, which was exposed and post-baked. development. The results of Comparative Example 9 were used as a reference in Table 5 for the resolution of the resist composition and LWR.

The smaller the resolution and the LWR value in Table 5, the more excellent the effect.

According to the above results, the photoacid generator of the present invention is excellent in resolution at the time of photolithography, and has an effect of reducing the LWR in the fine pattern.

In Examples 1 to 7 in which a sulfonium salt compound having a specific structure was used as the photodecomposable base and a photosensitive resin composition solution was used, the sensitivity, the resolution, and the LWR characteristics were excellent. On the other hand, in Comparative Examples 1 to 7 in which a photodegradable base containing no onium salt compound of the present invention was used, sensitivity, resolution, and LWR characteristics were still problematic.

In Examples 8 to 9 in which the onium salt compound having a specific structure was used as the photoacid generator and the photosensitive resin composition solution was used, the resolution and the LWR characteristics were excellent. On the other hand, in Comparative Examples 8 to 9 in which the photoacid generator containing no onium salt compound of the present invention was used, the resolution and the characteristics of LWR were still problematic.

From the above results, it is understood that the resist composition containing the onium salt compound of the several aspects of the present invention as a photoacid generator has excellent resolution at the time of photolithography and has an effect of reducing LWR in the fine pattern.

The above effect is considered to be because the photodecomposable base of the present invention has a guanamine structure as a highly polar atomic group in the anion portion, and has a high diffusion controlling effect on acid diffusion.

 [Industrial availability]  

Since the resist composition of one aspect of the present invention contains a photoacid generator having an appropriate acid strength, the onium salt compound which is not decomposed in the unexposed portion and the exposed portion functions as an acid diffusion controlling agent, and is ionized in the exposed portion. Further, secondary electrons are generated, and the generation of acid from the photo-acid generator can be increased. Therefore, the resolution at the time of photolithography is excellent, and the LWR (Line width roughness) in the fine pattern can be reduced.

Claims (16)

A photoacid generator containing an onium salt compound represented by the following formula (1), In the formula (1), R ¹ and R ² are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of R ¹ and R ² is not a hydrogen atom, and when R ¹ and R ² have a methylene group, at least 1 of R ¹ and R ² The methylene group may be substituted by a divalent hetero atom-containing group, and the R ¹ and R ² may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be selected from an oxygen atom or a sulfur atom. At least one of a nitrogen atom-containing group, a methylene group and a carbonyl group together with a nitrogen atom to which they are bonded form a ring structure, and L is a divalent linking group represented by -(CF ₂ ) _n -, n is An integer of 1 or more, and M ⁺ is a monovalent phosphonium cation. The photoacid generator according to claim 1, wherein the M ⁺ is a phosphonium cation having any one selected from the group consisting of sulfur (S), iodine (I), selenium (Se), and tellurium (Te). The photoacid generator according to claim 2, wherein the M ⁺ is any one of a phosphonium cation or an iodonium cation. The photoacid generator according to any one of claims 1 to 3, wherein L is -(CF ₂ ) ₂ - or -(CF ₂ ) ₃ -.  A resist composition containing the photoacid generator according to any one of claims 1 to 4.    The resist composition according to claim 5 further contains an acid-reactive compound.    The resist composition according to claim 6, wherein the acid-reactive compound is selected from the group consisting of a compound having a protective group deprotected by an acid, a compound having a polymerizable group polymerized by an acid, and an acid At least any one of cross-linking crosslinking agents.    A method of manufacturing a device, comprising: forming a resist film on a substrate using the resist composition according to any one of claims 5 to 7; and exposing the resist film using an active energy ray And a step of developing the exposed resist film.   A method for producing an onium salt compound, which comprises the step of subjecting a compound represented by the following formula (2) to salt exchange with an ionic compound M ⁺ X ^- to obtain a phosphonium salt compound represented by the following formula (1), In the formula (1), R ¹ and R ² are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of R ¹ and R ² is not a hydrogen atom, and when R ¹ and R ² have a methylene group, at least 1 of R ¹ and R ² The methylene group may be substituted by a divalent hetero atom-containing group, and the R ¹ and R ² may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be selected from an oxygen atom or a sulfur atom. At least one of a nitrogen atom-containing group, a methylene group and a carbonyl group together with a nitrogen atom to which they are bonded form a ring structure, and L is a divalent linking group represented by -(CF ₂ ) _n -, n is integer of at least 1, M ⁺ is a monovalent cation, in the formula (2), R ^1, R ^2, and R L is selected from the formula (1) is ^1, R ² and L are the same optional items, Q ⁺ is a monovalent cation away from M ^{+ of} the formula (1) Sub, M ⁺ X ^- M ⁺ with M in the formula (1) is the same as ^+, X ^- is a monovalent anion. The production method according to claim 9, wherein the M ⁺ is a phosphonium cation having any one selected from the group consisting of sulfur (S), iodine (I), selenium (Se), and tellurium (Te). The manufacturing method according to claim 10, wherein the M ⁺ is any one of a phosphonium cation or an iodonium cation. The production method according to any one of claims 9 to 11, wherein L is -(CF ₂ ) ₂ - or -(CF ₂ ) ₃ -. The production method according to any one of claims 9 to 12, wherein the Q ⁺ is an ammonium cation represented by the following formula (3), In the formula (3), R ³ to R ⁶ are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of R ³ to R ⁶ is not a hydrogen atom, and when R ³ to R ⁶ have a methylene group, at least 1 of R ³ to R ⁶ The methylene group may be substituted by a divalent hetero atom-containing group, and both of R ³ to R ⁶ may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be selected from a ring structure. At least any one of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group, and a carbonyl group together with a nitrogen atom to which they are bonded forms a ring structure. A salt compound which is represented by the following formula (2) and which can be used as a synthetic intermediate of the onium salt compound represented by the formula (1) contained in the photoacid generator according to any one of claims 1 to 4. , In the formula (2), R ¹ , R ² and L are selected from the same optional items as R ¹ , R ² and L of the formula (1), and Q ⁺ is other than M ^{+ of} the formula (1) Monovalent cation. The salt compound according to claim 14, wherein the Q ⁺ is an ammonium cation represented by the following formula (3), In the formula (3), R ³ to R ⁶ are each independently a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms with or without a substituent; with or without a linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms having a substituent; an aryl group having 5 to 30 carbon atoms with or without a substituent; and a carbon atom having or not having a substituent Any one of 3 to 30 heteroaryl groups, and at least one of R ³ to R ⁶ is not a hydrogen atom, and when R ³ to R ⁶ have a methylene group, at least 1 of R ³ to R ⁶ The methylene group may be substituted by a divalent hetero atom-containing group, and both of R ³ to R ⁶ may form a ring structure together with a nitrogen atom to which they are bonded by a single bond, or may be selected from a ring structure. At least any one of an oxygen atom, a sulfur atom, a nitrogen atom-containing group, a methylene group, and a carbonyl group together with a nitrogen atom to which they are bonded forms a ring structure. The salt compound according to claim 14 or 15, wherein L is -(CF ₂ ) ₂ - or -(CF ₂ ) ₃ -.