WO2019087626A1

WO2019087626A1 - Photo-acid generator, resist composition, and method for producing device using said resist composition

Info

Publication number: WO2019087626A1
Application number: PCT/JP2018/035787
Authority: WO
Inventors: 昴宏鎌倉; 内海　義之
Original assignee: 東洋合成工業株式会社
Priority date: 2017-10-31
Filing date: 2018-09-26
Publication date: 2019-05-09
Also published as: TW201925410A; JP7171601B2; JPWO2019087626A1; TWI794304B

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 device using the resist composition

Some aspects of the present invention relate to a photoacid generator, and more particularly to a photoacid generator suitably used for a resist composition for lithography. Further, some aspects of the present invention relate to a resist composition containing the above-mentioned photoacid generator, and a method of manufacturing a device using the resist composition.

BACKGROUND ART In recent years, manufacture of display devices such as liquid crystal displays (LCDs) and organic EL displays (OLEDs) and formation of semiconductor elements are actively performed by making full use of photolithography technology using a photoresist. In the above-mentioned electronic parts and packages of electronic products and the like, light such as i ray of wavelength 365 nm, h ray (405 nm) and g ray (436 nm) of longer wavelength are widely used as active energy rays.

As the integration of devices advances and the demand for miniaturization of lithography technology increases, KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), extreme ultraviolet light (hereinafter also referred to as “EUV”, wavelength 13.3). High energy rays such as 5 nm) and electron beams (hereinafter also referred to as "EB") tend to be used for exposure. Lithography techniques using light of these short wavelengths, in particular electron beam or extreme ultraviolet (EUV), can be manufactured by single patterning, and therefore show high sensitivity to electron beam or extreme ultraviolet (EUV) etc. The need for resist compositions is expected to further increase in the future.

With the shortening of the wavelength of the exposure light source, the resist composition is required to have improved sensitivity to the exposure light source and improved lithography characteristics having a resolution capable of reproducing the formation of a fine dimensional pattern. A chemically amplified resist using a photoacid generator is known as a resist composition that satisfies such requirements (Patent Document 1).
However, with the rapid miniaturization, in chemically amplified resists using a photoacid generator, the acid generated by exposure diffuses in the resist, greatly affecting the performance of lithography, and line width of contrast and line pattern There is a problem that the roughness (LWR) characteristics are reduced. Therefore, for the purpose of appropriately controlling the diffusion of the acid generated from the photoacid generator, it has been proposed that the resist composition contain an acid diffusion control agent to enhance resolution (Patent Document 2). On the other hand, if the acid diffusivity is controlled too much, the acid generation efficiency may be reduced and the contrast may be reduced.
Therefore, it has been proposed to improve the contrast by using a photodisintegrable base which is decomposed by exposure and loses acid diffusion controllability as an acid diffusion control agent (Patent Document 3). Examples of photodisintegrable bases include weak acid onium salts. The photodisintegrable base suppresses the acid decomposition reaction of the acid labile group by replacing the strong acid generated from another photoacid generator with the weak acid onium salt upon exposure and replacing the strong acid with a strong acid, It serves to reduce the acid diffusion distance, and it apparently functions as a quencher to become an acid diffusion control agent.

JP-A-9-90637 JP 2004-191764 A JP, 2010-66492, A

Since sensitivity, resolution, and pattern performance such as LWR are in a trade-off relationship, it is difficult for the conventional chemically amplified resist composition to simultaneously satisfy the characteristics of sensitivity, resolution, and pattern performance such as LWR. In the acid diffusion control agent proposed by the said patent document 2, a subject remains in the point that contrast is bad. Moreover, the photodisintegrable base proposed by the said patent document 3 has a subject by the point of the control under control of acid diffusion length.

An object of some aspects of the present invention is to provide a photoacid generator used for a resist composition excellent in the characteristics of sensitivity, resolution and pattern performance.
Another object of some embodiments of the present invention is to provide a resist composition containing the photoacid generator and a method of manufacturing a device using the resist composition.

As a result of intensive studies to solve the above problems, the present inventors have found that the characteristics of sensitivity, resolution and pattern performance can be improved by containing a specific onium salt compound as a photoacid generator of a resist composition. We have completed several aspects of the present 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), each of R ¹ and R ² independently represents a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have; an aryl group having 5 to 30 carbon atoms which may have a substituent; and And C3-30 heteroaryl group; and any one selected from the group consisting of and optionally at least one of which is not a hydrogen atom.
When R ¹ and R ² have a methylene group, at least one methylene group in R ¹ and R ² may be substituted with a divalent hetero atom-containing group.
R ¹ and R ² are bonded to each other directly through a single bond or 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 You may form a ring structure with a nitrogen atom.
L is a divalent linking group represented by-(CF ₂ ) _n- , and n is an integer of 1 or more.
M ⁺ is a monovalent onium cation.

Another aspect of the present invention is a photoacid generator and a resist composition containing the above onium salt compound.

In another embodiment of the present invention, the resist composition further contains an acid reactive compound.

Another aspect of the present invention is that the acid-reactive compound is a compound having a protecting group which is deprotected by an acid, a compound having a polymerizable group which is polymerized by an acid, and a crosslinking agent having a crosslinking action by an acid. At least one selected from the group consisting of

Furthermore, another aspect of the present invention is a process of forming a resist film on a substrate using the resist composition, a process of exposing the resist film using active energy rays, and developing the exposed resist film. And a process of manufacturing the device.

Another aspect of the present invention is a method for producing the above onium salt compound.

Another aspect of the present invention, a manufacturing method of the onium salt compound, the compound represented by the ionic compound M ⁺ X by the following formula (2) ^- and salt exchange with, represented by the following formula (1) And obtaining an onium salt compound.

In the above formula (1), each of R ¹ and R ² independently represents a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have; an aryl group having 5 to 30 carbon atoms which may have a substituent; and And C3-30 heteroaryl group; and any one selected from the group consisting of and optionally at least one of which is not a hydrogen atom.
When R ¹ and R ² have a methylene group, at least one methylene group in R ¹ and R ² may be substituted with a divalent hetero atom-containing group.
R ¹ and R ² are bonded to each other directly through a single bond or 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 You may form a ring structure with a nitrogen atom.
L is a divalent linking group represented by-(CF ₂ ) _n- , and n is an integer of 1 or more.
M ⁺ is a monovalent onium cation.
In the above formula ^(2), R 1, ^{R 2} and L are selected from the same options as ^R 1, ^{R 2} and L in the formula (1).
Q ⁺ is a monovalent cation other than ^{M +} in formula (1).
M ⁺ X ^- of ^{M +} is the same as the ^{M +} of the formula (1), X ^- is a monovalent anion.

Another aspect of the present invention is a salt compound represented by the following formula (2) which is useful as a synthetic intermediate of the above onium salt compound.

In the above formula ^(2), R 1, ^{R 2} and L are selected from the same options as ^R 1, ^{R 2} and L in the formula (1).
Q ⁺ is a monovalent cation other than ^{M +} in formula (1).

Another embodiment of the present invention is that the above M ⁺ is an onium cation having any atom selected from the group consisting of sulfur (S), iodine (I), selenium (Se) and tellurium (Te) is there.

In another aspect of the present invention, the M ⁺ is either a sulfonium cation or an iodonium cation.

Another aspect of the present invention is that L is-(CF ₂ ) ₂ -or-(CF ₂ ) _3- .

Another embodiment of the present invention is that the above Q ⁺ is an ammonium cation represented by the following formula (3).

In the above formula (3), R ³ to R ⁶ each independently represent a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have; an aryl group having 5 to 30 carbon atoms which may have a substituent; and And C3-30 heteroaryl group; and any one selected from the group consisting of and optionally at least one of which is not a hydrogen atom.
When R ³ to R ⁶ have a methylene group, at least one methylene group in 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 be a single bond directly or via 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 They may form a ring structure with the nitrogen atom to which they are attached.

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

Hereinafter, some aspects of the present invention will be described.
<1> Photoacid Generator The photoacid generator of one aspect of the present invention is characterized by containing an onium salt compound having a specific structure.
The photoacid generator can improve the characteristics of sensitivity, resolution and pattern performance by including an onium salt compound having a specific anion structure. In more detail, the said photo-acid generator can control acid diffusivity moderately by having an anion structure represented by the said Formula (1). In addition, since the photoacid generator can act as a photodisintegrable base when used in combination with other specific photoacid generators, the characteristics of sensitivity, resolution and pattern performance can be further improved.

The photoacid generator decomposes upon exposure to active energy rays. Therefore, when a resist composition containing the photoacid generator of some embodiments of the present invention as a photodisintegrable base and further containing another photoacid generator is used for a photoresist, the photodisintegrable base in the exposed portion is It decomposes, loses acid diffusion controllability, and the secondary electrons generated by the decomposition may act on the other photoacid generator to improve acid generation from the other photoacid generator. On the other hand, in the unexposed area, since the photodisintegrable base is a salt having a conjugate base weaker than other photoacid generators, it reacts with the acid generated from other photoacid generators to generate other photoacid generators. An acid derived from an acid can be inactivated and act as an acid diffusion control agent. Therefore, when the photoacid generator of one aspect of the present invention is used as a photodisintegrable base in a resist composition, it is possible to obtain a resist composition excellent in the characteristics of sensitivity, resolution and pattern formation ability.

Hereinafter, some embodiments of the present invention will be specifically described, but the present invention is not limited thereto.

<1-1> Anion of Onium Salt Compound The anion of the onium salt compound in one aspect of the present invention is represented by the above formula (1).
Examples of the linear alkyl group having 1 to 30 carbon atoms as R ¹ and R ² include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n- And linear alkyl groups such as octyl and n-dodecyl groups. In addition, at least one of the carbon-carbon single bonds in the linear alkyl group may be an alkenyl group substituted with a carbon-carbon double bond.

Examples of the branched alkyl group having 1 to 30 carbon atoms as R ¹ and R ² include isopropyl group, isobutyl group, tert-butyl group, isopentyl group, tert-pentyl group, 2-ethyloctyl group and 2-ethyldecyl group Etc. can be mentioned. In addition, at least one of the carbon-carbon single bonds in the branched alkyl group may be an alkenyl group substituted with a carbon-carbon double bond.
Examples of the cyclic alkyl group having 1 to 30 carbon atoms as R ¹ and R ² include cyclic alkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group and decahydronaphthyl group.
In addition to the above cyclic alkyl groups, spiro-type cyclic alkyl groups such as spiro [3,4] octyl group and spirobicyclopentyl group; bridging such as norbornyl group, tricyclodecanyl group, tetracyclododecanyl group and adamantyl group And cyclic alkyl groups such as decaline and condensed cyclic alkyl groups having a steroid skeleton shown below, etc .; and the like. In addition, at least one of the carbon-carbon single bonds in the branched alkyl group may be an alkenyl group substituted with a carbon-carbon double bond.

Further, in place of at least one methylene group of these alkyl groups, a divalent hetero atom-containing group may be contained. Examples of the hetero atom-containing group include -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH-CO-O-, and -O. -CO-NH -, - S - , - SO -, - S (O) 2 -, - S (O) 2 O-, and selected from the group consisting of _{-CO-O-CH 2 -CO-} O- , etc. It is at least one of the These may be included in combination as appropriate. These substituents may also be contained in the ring structure.
Examples of the alkyl group containing a divalent hetero atom-containing group include an alkoxy group; an alkyl carbonyloxy group; an alkyl group having a heterocyclic structure such as a lactone structure, a sultone structure and a lactam structure; and the like.

Examples of the aryl group having 5 to 30 carbon atoms include monovalent aryl groups such as cyclopentadienyl group, phenyl group, naphthyl group, anthracenyl group, phenanthrenyl group and azulenyl group. Further, it may be a monovalent heteroaryl group having 3 to 30 carbon atoms which contains a hetero atom in place of the carbon atom in the ring of the above aryl group. Examples of the heteroaryl group include monovalent heteroaryl groups having a skeleton such as furan, thiophene, imidazole, pyran, chromene, thianthrene, dibenzothiophene, xanthene and the like.

As a substituent which the said alkyl group, an alkenyl group, an aryl group and heteroaryl group may have, a linear or cyclic alkyl group (R ^Sp ); a linear or cyclic alkenyl group; said alkyl group (R ^Sp In place of at least one of the methylene groups of -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 - at least one hetero atom selected from the group consisting of An alkyl group containing a containing group in the skeleton; an alkenyl group containing the hetero atom-containing group in the skeleton instead of at least one methylene group of the alkenyl group; an aryl group (Ar ^Sp ); Instead of carbon atom A heteroaryl group which may contain a hydrogen atom; a hydroxy group; and a halogen atom. Among the above-mentioned hetero atom-containing groups, in -NHCO-, -CONH-, -NH-CO-O- and -O-CO-NH-, a hydrogen atom may be substituted by R ^Sp or Ar ^Sp .
As said R ^Sp , the linear, branched or cyclic alkyl group similar to said R is mentioned. As Ar ^Sp , the same aryl group as the above R ¹ and R ² can be mentioned. The alkyl group as R ¹ and R ^2, alkenyl group, the total number of carbon atoms in R ¹ and R ² when an aryl group and the heteroaryl group has a substituent, the carbon atoms including the substituent Preferably it is a number.
When the alkyl group as R ¹ and R ² has a substituent, the total number of carbon atoms of R ¹ and R ² is 1 to 30, preferably 4 to 20, and more preferably 4 to 12 It is.
When the alkenyl group as R ¹ and R ² has a substituent, the total number of carbon atoms of R ¹ and R ² is 2 to 30, preferably 5 to 20, and more preferably 6 to 12 It is.
When the aryl group as R ¹ and R ² has a substituent, the total number of carbon atoms of R ¹ and R ² is 5 to 30, preferably 6 to 14, and more preferably 6 to 11. It is.
When the heteroaryl group as R ¹ and R ² has a substituent, the total number of carbon atoms of R ¹ and R ² is 3 to 30, preferably 4 to 13, and more preferably 5 to 10
Examples of the alkyl group (R ^Sp ), the alkenyl group and the aryl group (Ar ^Sp ) as the substituent include the same alkyl groups as the above R ¹ and R ² , the above alkenyl groups and the above aryl groups.
As a halogen atom as a substituent, a fluorine atom, a chlorine atom, a bromine atom, etc. are mentioned.

R ¹ and R ² are a nitrogen to which they are directly bonded via a single bond or 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 You may form a ring structure with an atom.
As said nitrogen atom containing group, what is necessary is just to contain the nitrogen atom in the said hetero atom containing group. For example, 2 containing nitrogen such as -NHCO-, -CONH-, -NH-CO-O-, -O-CO-NH-, -N (R ₂ ^Sp ₂ ) _2- , -N (Ar ₂ ^Sp ₂ ) ₂ etc. Valence groups are mentioned. In the above -NHCO-, -CONH-, -NH-CO-O- and -O-CO-NH-, a hydrogen atom may be substituted by the above R ^Sp or Ar ^Sp . R can be selected from the same options as R ¹ and R ² 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, more preferably 3 or more.

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

<1-2> Cation of Onium Salt Compound

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

As onium cations having a sulfur (S) atom, sulfonium cations shown below can be mentioned.

In the above formulas, R ^a1 to R ^a3 are each independently a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic alkenyl group which may have a substituent, substituted The aryl group which may have a group, the heteroaryl group which may have a substituent, etc. are mentioned.
Examples of the alkyl group, alkenyl group, aryl group and heteroaryl group of R ^a1 to R ^a3 include the same as the alkyl group, alkenyl group, aryl group and heteroaryl group as R ¹ described above.

Specific examples of the sulfonium cation include, for example, trimethylsulfonium cation, tributylsulfonium cation, dimethyl (2-oxocyclohexyl) sulfonium cation, bis (2-oxocyclohexyl) methylsulfonium cation, (10-camphenoyl) methyl (2-oxocyclohexyl) ) Sulfonium cation, (2-norbornyl) methyl (2-oxocyclohexyl) sulfonium cation, triphenyl sulfonium cation, diphenyl tolyl sulfonium cation, diphenyl xylyl sulfonium cation, mesityl diphenyl sulfonium cation, (t-butylphenyl) diphenyl sulfonium cation , (Octylphenyl) diphenyl sulfonium cation, (cyclohexylpheny ) Diphenylsulfonium cation, biphenyldiphenylsulfonium cation, (hydroxymethylphenyl) diphenylsulfonium cation, (methoxymethylphenyl) diphenylsulfonium cation, (acetylphenyl) diphenylsulfonium cation, (benzoylphenyl) diphenylsulfonium cation, (hydroxycarbonylphenyl) diphenyl Sulfonium cation, (methoxycarbonylphenyl) diphenylsulfonium cation, (trifluoromethylphenyl) diphenylsulfonium cation, (fluorophenyl) diphenylsulfonium cation, (chlorophenyl) diphenylsulfonium cation, (bromophenyl) diphenylsulfonium cation, (iodophenyl) diphenyl Sulfonium cation, pentafluorophenyl diphenyl sulfonium cation, (hydroxyphenyl) diphenyl sulfonium cation, (methoxyphenyl) diphenyl sulfonium cation, (butoxyphenyl) diphenyl sulfonium cation, (acetyloxyphenyl) diphenyl sulfonium cation, (benzoyloxyphenyl) diphenyl Sulfonium cation, (dimethylcarbamoylphenyl) diphenylsulfonium cation, (acetylamidophenyl) diphenylsulfonium cation, phenyl ditolyl sulfonium cation, phenyl dixyl sulfonium cation, dimesityl phenyl sulfonium cation, bis (t-butyl phenyl) phenyl sulfonium cation , Bis (octyl) Phenyl) phenylsulfonium cation, bis (cyclohexylphenyl) phenylsulfonium cation, dibiphenylphenylsulfonium cation, bis (hydroxymethylphenyl) phenylsulfonium cation, bis (methoxymethylphenyl) phenylsulfonium cation, bis (acetylphenyl) phenylsulfonium cation, Bis (benzoylphenyl) phenylsulfonium cation, bis (hydroxycarbonylphenyl) phenylsulfonium cation, bis (methoxycarbonylphenyl) phenylsulfonium cation, bis (trifluoromethylphenyl) phenylsulfonium cation, bis (fluorophenyl) phenylsulfonium cation, bis (Chlorophenyl) phenyl sulfonium cut , Bis (bromophenyl) phenyl sulfonium cation, bis (iodophenyl) phenyl sulfonium cation, dipentafluorophenylphenyl sulfonium cation, bis (hydroxyphenyl) phenyl sulfonium cation, bis (methoxyphenyl) phenyl sulfonium cation, bis (butoxyphenyl) ) Phenylsulfonium cation, bis (acetyloxyphenyl) phenylsulfonium cation, bis (benzoyloxyphenyl) phenylsulfonium cation, bis (dimethylcarbamoylphenyl) phenylsulfonium cation, bis (acetylamidophenyl) phenylsulfonium cation, tristrithylsulfonium cation, Triskisilylsulfonium cation, trismesitylphene Sulfonium cation, tris (t-butylphenyl) sulfonium cation, tris (octylphenyl) sulfonium cation, tris (cyclohexylphenyl) sulfonium cation, tribiphenylsulfonium cation, tris (hydroxymethylphenyl) sulfonium cation, tris (methoxymethylphenyl) sulfonium Cation, tris (acetylphenyl) sulfonium cation, tris (benzoylphenyl) sulfonium cation, tris (hydroxycarbonylphenyl) sulfonium cation, tris (methoxycarbonylphenyl) sulfonium cation, tris (trifluoromethylphenyl) sulfonium cation, tris (fluorophenyl) ) Sulfonium cation, tris (chlorophenyl) Sulfonium cation, tris (bromophenyl) sulfonium cation, tris (iodophenyl) sulfonium cation, dipentafluorophenyl sulfonium cation, tris (hydroxyphenyl) sulfonium cation, tris (methoxyphenyl) sulfonium cation, tris (butoxyphenyl) sulfonium cation, Tris (acetyloxyphenyl) sulfonium cation, tris (benzoyloxyphenyl) sulfonium cation, tris (dimethylcarbamoylphenyl) sulfonium cation, tris (acetylamidophenyl) sulfonium cation, methyl diphenyl sulfonium cation, ethyl diphenyl sulfonium cation, butyl diphenyl sulfonium cation , Hexyl diphenyl sul Sodium cation, octyl diphenyl sulfonium cation, cyclohexyl diphenyl sulfonium cation, 2-oxocyclohexyl diphenyl sulfonium cation, norbornyl diphenyl sulfonium cation, canphenoyl diphenyl sulfonium cation, pinanoyl diphenyl sulfonium cation, naphthyl diphenyl sulfonium cation, anthranyl diphenyl sulfonium cation , Benzyl diphenyl sulfonium cation, trifluoromethyl diphenyl sulfonium cation, methoxycarbonylmethyl diphenyl sulfonium cation, butoxycarbonyl methyl diphenyl sulfonium cation, benzoyl methyl diphenyl sulfonium cation, (methylthiophenyl) diphenyl sulfone And (phenylthiophenyl) diphenylsulfonium cation, (acetylphenylthiophenyl) diphenylsulfonium cation, dimethylphenylsulfonium cation, diethylphenylsulfonium cation, dibutylphenylsulfonium cation, dihexylphenylsulfonium cation, dioctylphenylsulfonium cation, dicyclohexylphenylsulfonium cation Bis (2-oxocyclohexyl) phenylsulfonium cation, dinorbornylphenylsulfonium cation, dicamphenoyl phenylsulfonium cation, dipinanoylphenylsulfonium cation, dinaphthylphenylsulfonium cation, dibenzylphenylsulfonium cation, trifluoromethyldiethyl Phenylsulfonium cation, bis (methoxycarbonylmethyl) phenylsulfonium cation, bis (butoxycarbonylmethyl) phenylsulfonium cation, dibenzoylmethylphenylsulfonium cation, bis (methylthiophenyl) phenylsulfonium cation, bis (phenylthiophenyl) phenylsulfonium cation, Bis (acetylphenylthiophenyl) phenylsulfonium cation, dimethyl (2-oxocyclohexyl) sulfonium cation, bis (2-oxocyclohexyl) methylsulfonium cation, (10-camphenoyl) methyl (2-oxocyclohexyl) sulfonium cation, (2- Norbornyl) methyl (2-oxocyclohexyl) sulfonium cation, trimethyl Sulfonium cation, triethylsulfonium cation, tributylsulfonium cation, dihexylmethylsulfonium cation, trioctylsulfonium cation, dicyclohexylethylsulfonium cation, methyltetrahydrothiophenium cation, methyltetrahydrothiophenium cation, triphenyloxosulfonium cation, bis [4 And-(diphenylsulfonio) phenyl] sulfide-bis cation and the like. However, sulfonium cations are not limited to these.

As an onium cation which has an iodine (I) atom, the iodonium cation shown below is mentioned.

In the above formulas, R ^a1 to R ^a2 are each independently a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic alkenyl group which may have a substituent, substituted The aryl group which may have a group, the heteroaryl group which may have a substituent, etc. are mentioned.
Examples of the alkyl group, alkenyl group, aryl group and heteroaryl group of R ^a1 to R ^a2 include the same as the alkyl group, alkenyl group, aryl group and heteroaryl group as R ¹ described above.

Specifically as the iodonium cation, for example, diphenyliodonium cation, bis- (t-butylphenyl) iodonium cation, (methoxyphenyl) phenyliodonium cation, (butoxyphenyl) phenyliodonium cation, trifluoroethylphenyliodonium cation, pentafluoro And phenylphenyliodonium cation and the like. However, iodonium cations are not limited to these.

As an onium cation which has a selenium (Se) atom, the selenium cation shown below is mentioned.

Specific examples of the selenium cation include triphenylselenium cation, tri-p-tolylselenium cation, tri-o-tolylselenium cation, tris (4-methoxyphenyl) selenium cation, 1-naphthyldiphenylselenium cation, tris 4-fluorophenyl) selenium cation, tri-1-naphthylselenium cation, tri-2-naphthylselenium cation, tris (4-hydroxyphenyl) selenium cation, 4- (phenylthio) phenyldiphenylselenium cation, 4- (p-tolylthio) ) Phenyldi-p-tolylselenium cation, diphenylphenacylselenium cation, diphenylbenzylselenium cation, diphenylmethylselenium cation, phenyl group Benzylselenium cation, 4-hydroxyphenylmethylbenzylselenium cation, phenylmethylphenacylselenium cation, 4-hydroxyphenylmethylphenacylselenium cation, 4-methoxyphenylmethylphenacylselenium cation, dimethylphensylselenium cation, phenacyltetrahydrofuran There may be mentioned selenophenium cation, dimethylbenzylselenium cation, benzyltetrahydroselenophenium cation, octadecylmethylphenacylselenium cation and the like. However, selenium cations are not limited to these.

As an onium cation which has a tellurium (Te) atom, the tellurium cation shown below is mentioned.

Specific examples of the tellurium cation include triphenyltellurium cation, (2-methylphenyl) diphenyltellurium cation, (3-methylphenyl) diphenyltellurium cation, and (4-methylphenyl) diphenyltellurium cation, (1,3,5-trimethylphenyl) diphenyl tellurium cation, tri (4-methylphenyl) tellurium cation, tri (1,3,5-trimethylphenyl) tellurium cation, (4-methoxyphenyl) diphenyl tellurium Cation, tri (4-ethoxyphenyl) tellurium cation, tri (2,6-dimethoxyphenyl) tellurium cation, tri (4-hydroxy-2-methylphenyl) tellurium cation, tri (2,3,4,5 , 6-pentafluorophenyl ) Tellurium cation, (1-naphthyl) diphenyl ether cation, phenyldibenzo tellurocarbonyl Fe cation, and (4 phenyltelluro) phenyl diphenyl ether cation like. However, the tellurium cation is not limited to these.

<1-3> onium salt compounds the formula (1) onium salt compound represented by Since compounds having a specific structure, KrF excimer laser light, ArF excimer laser, F ₂ excimer laser light, electron beams, X It is useful as a photoacid generator which is decomposed efficiently by irradiation of active energy rays such as ray and EUV and generates an acid having appropriate acid strength. Moreover, since it has an amide structure in an anion part, it has the effect that acid diffusion length reduces. Therefore, when it is used as a photoacid generator of a resist composition, it has an effect of being excellent in resolution in lithography and capable of reducing LWR (Line Width Roughness) in a fine pattern.

In some embodiments of the present invention, the present invention is not limited to aqueous development using an alkaline developer, but is applicable to aqueous development using a neutral developer, organic solvent development using an organic solvent developer, and the like.

The onium salt compound may be added to the resist composition as a low molecular weight component but may be a polymer contained as a unit. That is, the onium salt compound represented by the said Formula (1) may be the aspect contained in the polymer as a unit so that it might couple | bond with a polymer principal chain in any position of this compound. For example, in the case of the onium salt compound represented by the above formula (1), in place of one H in R ¹ and R ² , it has a bond directly or via a linking group to the polymer main chain preferable. As a unit which comprises a polymer, the unit derived from the monomer which has radically polymerizable groups, such as a vinyl group, an isopropenyl group, an acryloxy group, and a methacryl oxy group, is preferable. The polymer may be a polymer containing units other than the unit corresponding to the onium salt compound. Details will be described later.
The above onium salt compound when a polymer, preferably the number of carbon atoms of the R ¹ and R ² in Formula (1) shall be excluding the number of carbon atoms of the polymer backbone.

<1-4> Method of Producing Onium Salt Compound In the onium salt compound according to one aspect of the present invention, the compound represented by the following formula (2) is salt-exchanged with an ionic compound M ⁺ X ⁻ to obtain the above formula (1) It can manufacture by the manufacturing method of the onium salt compound including the process of obtaining the onium salt compound represented by these.

^R 1, ^{R 2} and L in the formula (2) is selected from the same options as ^R 1, ^{R 2} and L in the formula (1).
Q ⁺ in the above formula (2) is a monovalent cation other than M ^{+ in the} above formula (1).
^M + X in the above formula (2) ^- the ^{M +} are the same as ^{M +} of the formula (1), X ^- is a monovalent anion.

It is preferable that said Q ^<+> is an ammonium cation represented by following formula (3).

In the above formula (3), R ³ to R ⁶ each independently represent a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have; an aryl group having 5 to 30 carbon atoms which may have a substituent; and And C3-30 heteroaryl group; and any one selected from the group consisting of and optionally at least one of which is not a hydrogen atom.

When R ³ to R ⁶ have a methylene group, at least one methylene group in 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 be a single bond directly or via 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 They may form a ring structure with the nitrogen atom to which they are attached.
R ³ to R ⁶ in the above formula (3) are selected from the same options as R ¹ and R ² in the above formula (1).

The compound represented by the above formula (2) ionic compound M ⁺ X ^- How to exchange salt is not particularly limited, may be carried out under normal conditions. For example, salt exchange is carried out by adding an ionic compound M ⁺ X ⁻ and an organic solvent to a compound represented by the above formula (2) in an aqueous solvent and stirring, and the organic layer is represented by the above formula (1) An onium salt compound can be obtained. As said organic solvent used for salt exchange, it may be a solvent used for normal salt exchange. Examples of the organic solvent include halogen solvents, ester solvents, ketone solvents, ether solvents and aromatic solvents. Also, these solvents may be arbitrarily combined.

The above compound (2) can be produced, for example, by the following method.
Incidentally, ^{R 1} and ^{R 2} in the following synthesis examples and correspond to ^{R 1} and ^{R 2} in the formula (1).

The compound (2) can be produced, for example, by any of the following formula (A1) to the following formula (A3).
In the following formula (A1), an amide bond is formed by the reaction of a cyclic acid anhydride (4) and a primary or secondary amine and the cyclic acid anhydride (4) is opened to form an onium salt compound (2a) Do. Then, an onium salt compound (2a) an ionic compound M ⁺ X ^- salt exchanged with, obtaining an onium salt compound (1).
At this time, an ammonium cation derived from a primary or secondary amine is generated, and the ammonium cation (N ⁺ H ₂ (R ¹ ) (R ² )) of the onium salt (2a) is represented by the above formula (2). It corresponds to counter cation (Q ⁺ ).
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.

On the other hand, in the following formula (A2), an ammonium cation derived from the tertiary amine by performing a ring-opening reaction in the presence of a tertiary amine in addition to the primary or secondary amine in the above formula (A1); Ammonium cations derived from secondary or secondary amines are produced. 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) originates in the substituent of the amine used as a raw material. Specifically, there are the following cases.
· R ¹⁰¹ and R ¹⁰² are derived from R ¹ and R ^{2 of the} primary amine or secondary amine, and R ¹⁰³ is derived from a hydrogen atom of the primary amine or secondary amine (also referred to as “ammonium cation Qb 1” In the case of
In the case where R ¹⁰¹ to R ¹⁰³ are derived from R ⁷ to R ⁹ of the above-mentioned tertiary amine (also referred to as “ammonium cation Qb2”).
When it is a mixture of the above ammonium cation Qb1 and the above ammonium cation Qb2.
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.
Then, an onium salt compound (2b) of the ionic compound M ⁺ X ^- salt exchanged with, obtaining an 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 counter cation (Q ⁺ ) of the compound represented by the above formula (2) tends to be 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 )), in the above formula (2) The counter cation (Q ⁺ ) of the compound represented tends to be the ammonium cation Qb2.
In the formula (A2), the hydrophobicity of the primary or secondary amine (NH (R ¹ ) (R ² )) and the tertiary amine (NH (R ⁷ ) (R ⁸ ) (R ⁹ )) is comparable. At the same time, the counter cation (Q ⁺ ) of the compound represented by the above formula (2) tends to be a mixture of the ammonium cation Qb1 and the ammonium cation Qb2.

As shown in the following formula (A3), a quaternary ammonium salt (N) is used to the onium salt compound (2a) obtained in the above formula (A1) or the onium salt compound (2b) obtained in the above formula (A2) ^The salt exchange is carried out by the action of ⁺ (R ³ ) (R ⁴ ) (R ⁵ ) (R ⁶ ) Y ⁻ ) to derive another onium salt compound (2c). Then, an onium salt compound (2c) ionic compound M ⁺ X ^- further salt exchange may be obtained onium salt compound (1).

<1-5> Photoacid Generator Some embodiments of the present invention are photoacid generators containing the above onium salt compound.
When the above onium salt compound is contained in the resist composition together with other photoacid generators, the anion of the above onium salt compound has an acid strength equal to or higher than that of the anions of the other photoacid generators. It is preferable to use it because it acts as a photodisintegrable base.
More specifically, the photoacid generator in some embodiments of the present invention preferably has a pKa of -2 to 6. pKa is a value obtained by analysis using ACD labs (manufactured by Fujitsu Ltd.).

As mentioned above, the onium salt compound in some aspects of the invention may be a polymer. When the onium salt compound is a polymer, the polymer may be a homopolymer including a unit functioning as a photoacid generator, or may be a copolymer including other units. When it is a copolymer, as another unit, what acts as an acid reactive compound, and a hydroxy aryl group containing unit etc. are mentioned. Those acting as the acid-reactive compound, the hydroxyaryl group-containing unit and the like will be described later.

<2> Resist Composition One aspect of the present invention relates to a resist composition containing a photoacid generator in some aspects of the present invention. The resist composition preferably further contains the photoacid generator and an acid reactive compound.
The resist composition may also contain a second photoacid generator in addition to the photoacid generator (hereinafter also referred to as "first photoacid generator") according to some embodiments of the present invention. Good. When the second photogenerator is smaller than the pKa of the first photoacid generator, the first photoacid generator preferably functions as a photodisintegrable base.

The content of the first photoacid generator in the resist composition according to one aspect of the present invention is preferably 0.5 to 30 parts by mass with respect to 100 parts by mass of the acid-reactive compound described later, 1 The amount is more preferably 20 parts by mass, further preferably 2 to 10 parts by mass.
When the first photoacid generator is used as a photodisintegrable base, that is, when the resist composition contains a second photoacid generator, the content of the first photoacid generator in the resist composition Is preferably 1 to 100 parts by mass, and more preferably 3 to 75 parts by mass with respect to 100 parts by mass of the second photoacid generator. By incorporating the first photoacid generator in the resist composition within the above range, it is possible to have excellent properties in sensitivity, resolution and pattern formation ability.
In the calculation of the content, the organic solvent is not included in the resist composition component.
Moreover, when the said 1st photo-acid generator and 2nd photo-acid generator couple | bond with a polymer, it is set as the mass reference except polymer main chain.
The first photoacid generator may be used singly or in combination of two or more.

Hereinafter, each component contained in a resist composition is demonstrated.
<2-1> Second Photoacid Generator The resist composition of some embodiments of the present invention preferably contains a second photoacid generator.
The second photoacid generator is not particularly limited as long as it is used in a general resist composition, and, for example, onium salt compounds such as sulfonium salts and iodonium salts, N-sulfonyloxyimide compounds, oxime sulfonate compounds, Organic halogen compounds, sulfonyldiazomethane compounds and the like can be mentioned. These can be used singly or in combination of two or more.
Examples of sulfonium salts include those described in WO 2011/093139.

As described above, it is preferable to use an anion of the second photoacid generator that has an acid strength greater than that of the onium salt compound of the first photoacid generator.
More specifically, the second photoacid generator preferably has a pKa of -3 or less. As such an anion, a fluorine atom substituted sulfonic acid etc. are mentioned.

The second photoacid generator may be added to the resist composition as a low molecular weight component, but may be contained as a polymer unit. That is, the embodiment may be included in the polymer as a unit so as to be bonded to the polymer main chain at any position of the second photoacid generator. For example, when the second photoacid generator is a sulfonium salt, it is preferable to have a bond which is bonded to the polymer main chain directly or via a linking group, instead of one H of the substituent in the sulfonium salt.

The content of the second photoacid generator in the resist composition according to one aspect of the present invention is preferably 1 to 50 parts by mass, and more preferably 3 to 30 parts by mass with respect to 100 parts by mass of the acid reactive compound described later. It is more preferably part, and still more preferably 5 to 25 parts by mass.
When the said 2nd photo-acid generator couple | bonds with a polymer, it is set as the mass reference except polymer main chain.

<2-2> Acid-Reactive Compound The resist composition of some aspects of the present invention preferably contains an acid-reactive compound in addition to the second photoacid generator.
It is preferable that the above-mentioned acid-reactive compound has a protecting group which is deprotected by an acid, is polymerized by an acid, or is crosslinked by an acid. That is, the above-mentioned acid reactive compound is at least one selected from the group consisting of a compound having a protecting group which is deprotected by acid, a compound having a polymerizable group which is polymerized by acid, and a crosslinking agent which has a crosslinking action by acid. Is preferred.

The compound having a protective group which is deprotected by an acid is a compound which produces a polar group by deprotecting the protective group by an acid and changes the solubility in a developer. For example, in the case of aqueous development using an alkali developing solution etc., a compound having a protecting group which is deprotected by acid is insoluble in the alkali developing solution, but in the exposed area by the acid generated from the photoacid generator upon exposure. It is a compound which becomes soluble in an alkali developing solution by deprotecting the above-mentioned protective group from the above-mentioned compound.

In some embodiments of the present invention, it is not limited to the alkaline developer, and may be neutral developer or organic solvent development. Therefore, when an organic solvent developing solution is used, the compound having a protective group which is deprotected by acid is depolarated from the compound by the acid generated from the photoacid generator upon exposure in the exposed area. It is a compound which forms a group and decreases the solubility in an organic solvent developer.

As a polar group of the said acid-reactive compound, a hydroxy group, a carboxy group, an amino group, a sulfo group, etc. are mentioned.
The acid deprotecting group is a group obtained by protecting the hydrogen atom of the polar group with a protecting group. Specific examples of the protective group include tertiary alkyl ester group, acetal group, tetrahydropyranyl group, carbonate group, siloxy group and benzyloxy group. As the compound having the protective group, a compound having a styrene skeleton, a methacrylate or an acrylate skeleton in which the protective groups are pendant, and the like are suitably used.
The compound having a protecting group which is deprotected by an acid may be a protecting group-containing low molecular weight compound or a protecting group-containing polymer. In some embodiments of the present invention, the low molecular weight compound is one having a weight average molecular weight of less than 2000, and the polymer is one having a weight average molecular weight of 2000 or more.

The compound having a polymerizable group that is polymerized by an acid is a compound that changes the solubility in a developer by being polymerized by an acid. For example, in the case of aqueous development, it acts on a compound which is soluble in an aqueous developer, and after polymerization, reduces the solubility of the compound in an aqueous developer. Specifically, compounds having an epoxy group, a vinyloxy group, an oxetanyl group and the like can be mentioned.
The compound having a polymerizable group which is polymerized by an acid may be a polymerizable low molecular weight compound or a polymerizable polymer.

A crosslinking agent having a crosslinking action by an acid is a compound that changes the solubility in a developer by crosslinking with an acid. For example, in the case of aqueous development, it acts on a compound which is soluble in an aqueous developer, and reduces the solubility of the compound in an aqueous developer after polymerization or crosslinking. Specifically, crosslinking agents having an epoxy group, a vinyloxy group, a 1-alkoxyamino group, an oxetanyl group and the like can be mentioned. When the compound is a crosslinking agent having a crosslinking action, examples of the compound to be crosslinked, that is, a compound which reacts with the crosslinking agent to change the solubility in the developing solution include compounds having a phenolic hydroxyl group.
The compound having a crosslinking action by an acid may be a polymerizable low molecular weight 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 to which the reactive compound is bonded. As the other unit, for example, a unit (I) having at least one site selected from the group consisting of a lactone site, a sultone site, a lactam site and the like; a group having an ether bond, an ester bond, an acetal structure and the like, and hydroxy Examples include units (II) having at least one group selected from the group consisting of groups; hydroxyaryl group-containing units (III); and the like. Furthermore, a unit (IV) to which the first photoacid generator is bound and a unit (V) to which the second photoacid generator is bound may be contained.

In some embodiments of the present invention, the ratio of each unit of the polymer is not particularly limited, but when the unit to which the acid reactive compound is bound is included as a unit of the same polymer together with other units, the acid reaction The unit to which the organic compound is bonded is preferably 10 to 70 mol%, more preferably 15 to 65 mol%, and still more preferably 20 to 60 mol%, in all units of the polymer.

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

<2-3> Other Components In the resist composition according to one aspect of the present invention, an organic solvent, an acid diffusion control agent, and a surfactant used in a general resist composition as an optional component other than the above components as necessary. Organic carboxylic acids, dissolution inhibitors, stabilizers, dyes, sensitizers and the like may be contained in combination.

As an 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 propionate, 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-methyl pyrrolidone, N, N-dimethylformamide, γ-butyrolactone, N, N-dimethylaceto Amide, propylene carbonate, ethylene carbonate and the like are preferable. These organic solvents are used alone or in combination.

The acid diffusion control agent controls the diffusion phenomenon of the acid generated from the photoacid generator in the resist film, and has an effect of controlling an undesirable chemical reaction in the non-exposed area. Therefore, the storage stability of the obtained resist composition is further improved, and the resolution as the resist is further improved, and the line width change of the resist pattern due to the fluctuation of the drawing time from exposure to development can be suppressed. And a resist composition having excellent process stability.
Examples of the acid diffusion control agent include a compound having one nitrogen atom, a compound having two nitrogen atoms, a compound having three nitrogen atoms, an amide group-containing compound, a urea compound, a nitrogen-containing heterocyclic compound, etc. in the same molecule. Be Further, as the acid diffusion control agent, it is possible to use the above-mentioned photodisintegrable base other than the above onium salt compound of one aspect of the present invention which is photosensitized by exposure to generate a weak acid. Specifically, Japanese Patent No. 3577743, Japanese Patent Application Nos. 2001-215689, 2001-166476, 2008-102383, 2010-243773, 2011-37835 and 2012-173505 are provided. The compound as described in is mentioned.
When the acid diffusion control agent is contained, the content is preferably 0.01 to 20 parts by mass, and more preferably 0.03 to 15 parts by mass with respect to 100 parts by mass of the acid-reactive compound. And more preferably 0.05 to 10 parts by mass. The content does not include the first photoacid generator according to one aspect of the present invention.

The surfactant is preferably used to improve the coatability. Examples of surfactants include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters Agents, fluorosurfactants, organosiloxane polymers and the like.
The content of the surfactant is preferably 0.0001 to 2 parts by mass, and more preferably 0.0005 to 1 parts by mass with respect to 100 parts by mass of the acid-reactive compound.

Examples of the organic carboxylic acids include aliphatic carboxylic acids, alicyclic carboxylic acids, unsaturated aliphatic carboxylic acids, oxycarboxylic acids, alkoxycarboxylic acids, ketocarboxylic acids, benzoic acid derivatives, phthalic acid, terephthalic acid, isophthalic acid, 2 And naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid and the like. When electron beam exposure is performed in vacuum, there is a risk of volatilizing from the surface of the resist film and contaminating the inside of the drawing chamber. Therefore, preferable organic carboxylic acids are aromatic organic carboxylic acids, among which, for example, benzoic acid, 1-hydroxy-2-naphthoic acid and 2-hydroxy-3-naphthoic acid are preferred.
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, and still more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the acid-reactive compound. is there.
The resist composition component is preferably dissolved in the above organic solvent and dissolved at 1 to 40% by mass as solid concentration. More preferably, it is 1 to 30% by mass, and further preferably 3 to 20% by mass.

When the resist composition according to one aspect of the present invention contains a polymer, the polymer preferably has a weight average molecular weight of 2,000 to 200,000, more preferably 2,000 to 50,000, and still more preferably 2,000 to 15,000. . The preferred degree of dispersion (molecular weight distribution) (Mw / Mn) of the above polymer is 1.0 to 1.7, more preferably 1.0 to 1.2, from the viewpoint of sensitivity.
In some embodiments of the present invention, the weight average molecular weight and the degree of dispersion of the polymer are defined as polystyrene equivalent by GPC measurement.

The resist composition of one embodiment of the present invention may contain a fluorine-containing water-repellent polymer.
The above-mentioned fluorine-containing water-repellent polymer is not particularly limited, and those generally used in an immersion exposure process may be mentioned, and it is preferable that the fluorine atom content is larger than that of the above-mentioned polymer. Thereby, when forming a resist film using a resist composition, the above-mentioned fluorine-containing water-repellent polymer can be localized on the resist film surface due to the water repellency of the fluorine-containing water-repellent polymer .

As the fluorine content of the fluorine water-repellent polymer, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon groups in the fluorine water-repellent polymer be fluorinated, and it is more preferable that 50% or more is fluorinated preferable.

The content of the fluorine- and water-repellent polymer in the resist composition is 0.5 to 10 parts by mass with respect to 100 parts by mass of the above-mentioned polymer (not the fluorine-water-repellent polymer) of one embodiment of the present invention. Is preferable from the viewpoint of improving the hydrophobicity of the resist film. The fluorine- and water-repellent polymers may be used alone or in combination of two or more.

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

<3> Method of Manufacturing Device One aspect of the present invention is a step of forming a resist film by applying the above-mentioned resist composition on a substrate, etc., a step of exposing the above-mentioned resist film, and an exposed resist film And b. Developing the device.
One embodiment of the present invention provides a singulated chip comprising the steps of: forming a resist film using the above resist composition; exposing the resist film; and developing the exposed resist film. It may be a method of manufacturing a substrate having a front pattern.

The active energy ray used for exposure in the step of exposing the resist film may be any light capable of generating an acid by activating the onium salt compound according to one aspect of the present invention, such as KrF excimer laser light or ArF excimer laser light , F ₂ excimer laser light, electron beam, UV, visible light, X-ray, electron beam, ion beam, i-ray, EUV and the like.
In one aspect of the present invention, an electron beam (EB), extreme ultraviolet (EUV), etc. are preferably mentioned as the active energy ray used for exposure in the photolithography step.

The dose of light, the kind and blending ratio of each component in the photocurable composition, and varies depending on the film thickness and the like of the coating film is preferably 1 J / cm ² or less or 1000μC / cm ² or less.
When the resist composition contains the sensitizing compound or the corresponding sensitizing compound as a sensitizing unit in the polymer, it is also preferable to perform a second exposure with ultraviolet light or the like after irradiation with active energy rays.

Hereinafter, some aspects of the present invention will be described based on examples, but the present invention is not limited to these examples.

[Synthesis of Sulfonium Salt 1 (A-1)]

Synthesis of cyclohexylammonium 4- (cyclohexylaminocarbonyl) -2,2,3,3,4,4-hexafluorobutyrate Hexafluoroglutaric anhydride (25.4 g) is dissolved in methylene chloride (264 g), It was cooled to 5 ° C. Next, a methylene chloride solution (62 g) containing cyclohexylamine (29.0 g) was added dropwise and stirred 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 obtain the desired product (29.3 g) in a yield of 44%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 8.31 (brd, 3 H), 7.81 (brd, 1 H), 3.73-3.71 (m, 1 H), 3.08-3.00 (M, 1 H), 2.03-1.64 (m, 10 H), 1.43-1. 15 (m, 10 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-112.0 (t, 2F), -114.9 (t, 2F), -122.1 (m, 2F).

Synthesis of triphenylsulfonium 4- (cyclohexylaminocarbonyl) -2,2,3,3,4,4-hexafluorobutyrate The above ammonium salt (9.8 g) was purified water (88 g) and triphenylsulfonium methyl sulfate (15.0 g) and methylene chloride (88 g) were added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (44 g). The organic layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the target product (12.2 g) in a yield of 90%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 8.31 (brs, 1 H), 7.95-7.83 (m, 15 H), 3.68-3.64 (m, 1 H), 1.93 -1.53 (m, 5H), 1.44-1.12 (m, 5H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-111.9 (t, 2F), -114.7 (t, 2F), -122.0 (m, 2F).

[Synthesis of Sulfonium Salt 2 (A-2)]

Synthesis of 1-adamantane ammonium 4- (1-adamantaneaminocarbonyl) -2,2,3,3,4,4-hexafluorobutyrate Hexafluoroglutaric anhydride (19.0 g) in methylene chloride (160 g) And cooled to 5 ° C. Next, a methylene chloride solution (70 g) containing 1-aminoadamantane (33.7 g) was dropped, 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 washed five times with pure water (80 g). The organic layer was separated and dried under reduced pressure to give the target product (13.2 g) in a yield of 51%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 8.34 (brs, 3 H), 3.77-3.74 (m, 1 H), 2.30-1.67 (m, 30 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-112.2 (t, 2F), -114.6 (t, 2F), -122.5 (m, 2F).

Synthesis of triphenylsulfonium 4- (1-adamantaneaminocarbonyl) -2,2,3,3,4,4-hexafluoropropyrate The above ammonium salt (8.0 g) was purified water (30 g) and triphenyl Sulfonium methyl sulfate (6.3 g) and methylene chloride (99 g) were added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (41 g). The organic layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the target product (9.0 g) in a yield of 93%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 8.28 (brs, 1 H), 7.82-7.64 (m, 15 H), 2.28-1.63 (m, 15 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-112.1 (t, 2F), -114.5 (t, 2F), -122.5 (m, 2F).

[Synthesis of Sulfonium Salt 3 (A-3)]

Synthesis of morpholinium 3- (4-morpholinocarbonyl) -2,2,3,3-tetrafluoropropionate Dissolve tetrafluorosuccinic anhydride (4.2 g) in methylene chloride (46 g), It cooled. Next, a methylene chloride solution (16 g) containing morpholine (5.5 g) was added dropwise and stirred at 5 ° C. for 24 hours. After confirming the completion of the reaction, acetic acid (0.6 g) was added and washed five times with pure water (20 g). The organic layer was separated and dried under reduced pressure to obtain the desired product (3.1 g) in a yield of 37%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 6.68 (brs, 2 H), 3.95-3. 68 (m, 16 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ -108.8 (t, 2F), -113.5 (t, 2F).

Synthesis of triphenylsulfonium 3- (4-morpholinocarbonyl) -2,2,3,3-tetrafluoropropionate Ammonium salt (3.1 g) in pure water (19 g) and triphenyl sulfonium methyl sulfate (10 g) Methylene chloride (59 g) was added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (19 g). The organic layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the target product (11.0 g) in a yield of 79%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 7.91-7.79 (m, 15 H), 3.69-3. 58 (m, 8 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ -108.6 (t, 2F), -113.4 (t, 2F).

[Synthesis of Sulfonium Salt 4 (A-4)]

Synthesis of 1-ethoxycarbonylpiperazinium 4-[(1-ethoxycarbonyl) piperazinocarbonyl] -2,2,3,3,4,4-hexafluorobutyrate 1-ethoxycarbonylpiperazine (8.9 g Was dissolved in methylene chloride (40 g) and cooled to 5 ° C. Next, a methylene chloride solution (29 g) containing hexafluoroglutaric anhydride (5.0 g) was added dropwise and stirred at 5 ° C. for 24 hours. After confirming the completion of the reaction, acetic acid (0.7 g) was added and washed five times with pure water (30 g). The organic layer was separated and dried under reduced pressure to give the target product (6.1 g) in a yield of 51%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 6.68 (brs, 2 H), 4.05 (q, 4 H), 3.94-3. 24 (m, 16 H), 1.18 (t, 6 H) ). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-112.0 (t, 2F), -114.8 (t, 2F), -122.2 (m, 2F).

Synthesis of triphenylsulfonium 4-[(1-ethoxycarbonyl) piperazinocarbonyl] -2,2,3,3,4,4-hexafluorobutyrate The above ammonium salt (5.4 g) was purified water (88 g) And triphenylsulfonium methyl sulfate (4.5 g) and methylene chloride (63 g) were added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (25 g). The organic layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the target product (5.5 g) in a yield of 86%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 7.91-7.79 (m, 15 H), 4.11 (q, 2 H), 3.88-3. 39 (m, 4 H), 2.95 −2.91 (m, 4H), 1.17 (t, 3H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-111.7 (t, 2F), -114.6 (t, 2F), -122.1 (m, 2F).

[Synthesis of Sulfonium Salt 5]

Synthesis of anilinium 4- (phenylaminocarbonyl) -2,2,3,3,4,4-hexafluorobutyrate: Dissolve hexafluoroglutaric anhydride (2.7 g) in methylene chloride (25 g); It cooled to ° C. Then, a methylene chloride solution (8.0 g) containing aniline (3.0 g) was added dropwise and stirred at 5 ° C. for 24 hours. After confirming the completion of the reaction, acetic acid (0.6 g) was added and washed five times with pure water (15 g). The organic layer was separated and dried under reduced pressure to give the target product (4.5 g) in 90% yield. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, CDCl ₃ ) δ 7.21 (t, 4 H), 7.06 (brs, 3 H), 6.92-6. 86 (m, 6 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-112.5 (t, 2F), -114.5 (t, 2F), -123.4 (m, 2F).

Synthesis of triphenylsulfonium 4- (phenylaminocarbonyl) -2,2,3,3,4,4-hexafluorobutyrate The above ammonium salt (4.4 g) was purified water (22 g) and triphenyl sulfonium methyl sulfate (5.0 g) and methylene chloride (38 g) were added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (15 g). The organic layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the desired product (5.5 g) in a yield of 88%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, 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 (400 MHz, DMSO-d6) δ-112.4 (t, 2F),-114.4 (t, 2F), -123.2 (m, 2F).

[Synthesis of sulfonium salt 6]

Synthesis of dicyclohexylammonium 3- (N-dicyclohexylaminocarbonyl) -2,2,3,3-tetrafluoropropionate Hexafluoroglutaric anhydride (3.1 g) is dissolved in methylene chloride (46 g), 5 It cooled to ° C. Next, a methylene chloride solution (20 g) containing cyclohexylamine (8.4 g) was added dropwise and stirred at 5 ° C. for 24 hours. After confirming the completion of the reaction, the organic layer is washed 5 times with pure water (28 g), then the organic layer is separated, and the solvent is distilled off with a rotary evaporator to yield 62% of the desired product (5.1 g) I got it. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. 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 triphenylsulfonium 3- (N-dicyclohexylaminocarbonyl) -2,2,3,3-tetrafluoropropionate Ammonium salt (5.1 g) in pure water (30 g) and triphenyl sulfonium methyl sulfate (4) 9 g) and methylene chloride (45 g) were added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (30 g). The oil layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the target product (6.3 g) in a yield of 91%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, acetone-d6) δ 7.99-7.8 2 (m, 15 H), δ 3.80-3.65 (m, 2 H), 1.94-11. 11 (m, 20 H) . ¹⁹ F-NMR (400 MHz, DMSO-d6) δ -108.9 (t, 2F), -113.6 (t, 2F).

[Synthesis of Sulfonium Salt 7]

Synthesis of tetrabutylammonium 3- (N-ethylaminocarbonyl) -2,2,3,3-tetrafluoropropionate Hexafluoroglutaric anhydride (5.6 g) was dissolved in methylene chloride (35 g), It was cooled to 5 ° C. Next, a THF solution (30 g) of diethylamine was added dropwise, and stirred at 5 ° C. for 24 hours. After confirming the completion of the reaction, methylene chloride (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 five times with pure water (35 g). After that, the organic layer was separated, and the solvent was distilled off with a rotary evaporator to obtain the target product (9.4 g) in a yield of 73%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, CDCl 3) δ 9.05 (brs, 1 H), 3.94-3.87 (q, 2 H), 3.448 (t, 8 H), 1.74 (m, 8 H), 1.48 (m, 8 H), 1.33 (t, 3 H), 1.00 (t, 12 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-112.1 (t, 2F), -114.8 (t, 2F), -122.3 (m, 2F).

Synthesis of triphenylsulfonium 3- (N-ethylaminocarbonyl) -2,2,3,3-tetrafluoropropionate Ammonium salt (4.5 g) in pure water (23 g) and triphenyl sulfonium methyl sulfate (3 .5 g) and methylene chloride (45 g) were added and stirred at room temperature for 2 hours. The organic layer was separated and washed five times with pure water (23 g). The oil layer was separated from the reaction mixture, and the solvent was evaporated by a rotary evaporator to give the desired product (4.2 g) in a yield of 89%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, CDCl 3) δ 9.05 (brs, 1 H), 7.93-7.81 (m, 15 H) 3.94-3.87 (q, 2 H), 1.00 (t, t) 3H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-111.9 (t, 2F), -114.7 (t, 2F), -122.0 (m, 2F).

[Synthesis of Sulfonium Salt 8 (A-5)]

Synthesis of triphenylsulfonium 4- (1-adamantyloxycarbonyl) -2,2,3,3,4,4-hexafluorobutyrate 1-adamantanol (5.8 g) and pyridine (3.2 g) and chloride Methylene (60 g) was mixed and cooled to 5 ° C. Next, a methylene chloride solution (20 g) containing hexafluoroglutaric anhydride (9.4 g) was added dropwise and stirred at 5 ° C. for 1 hour. Thereafter, the reaction mixture was heated to reflux and stirred for further 48 hours. The reaction mixture was cooled to room temperature, pure water (110 g) was added, and the mixture was stirred for 30 minutes. The organic layer was separated and washed five times with pure water (64 g). The organic layer was separated, pure water (64 g) was added, triphenylsulfonium methyl sulfate (17.5 g) was added, and the mixture was stirred at room temperature for 2 hours. The organic layer was separated, and washed three times with 10% aqueous sodium carbonate solution (64 g) and five times with pure water (64 g). The organic layer was separated and the solvent was distilled off with a rotary evaporator. The resulting crude product was purified by silica gel column chromatography to give the desired product (9.2 g) in a 36% yield. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 7.93-7.77 (m, 15 H)
, 2.10-1.63 (m, 15 H). ¹⁹ F-NMR (400 MHz, DMSO-d6) δ-113.2 (t, 2 F), -114.9 (t, 2 F), -121. 4 (m, 2F)

[Synthesis of Sulfonium Salt 9 (A-6)]

Synthesis of triphenylsulfonium heptafluorobutyrate A 10% aqueous solution of sodium carbonate (85 g) is cooled to 5 ° C., heptafluorobutyric acid (15.0 g) is added dropwise over 20 minutes, and stirred for 30 minutes. An aqueous solution of sodium heptafluorobutyrate was prepared. Methylene chloride (330 g) and triphenylsulfonium methyl sulfate (29.0 g) were added thereto, and the mixture was warmed to room temperature and stirred for 4 hours. The organic layer was separated therefrom, and washed five times with pure water (33 g). The organic layer was separated, and the solvent was evaporated by a rotary evaporator to give the target product [R-2] (23.4 g) in a yield of 70%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below.
¹ H-NMR (400 MHz, DMSO-d6) δ 7.95-7.83 (m, 15 H).
¹⁹ F-NMR (400 MHz, DMSO-d6) δ -78.1 (t, 3 H), -115.6 (t, 2 H), -119.0 (m, 2 H).

[Synthesis of Sulfonium Salt 10 (A-9)]

Synthesis of triphenylsulfonium 4- (1-adamantylaminocarbonyl) butyrate Glutaric anhydride (12 g), 1-adamantanamine (15.0 g), DMAP (14 g) was added to toluene (100 g) and stirred and refluxed. The temperature rose to a temperature. After 72 hours, the reaction mixture was cooled to room temperature and the solvent was distilled off on a rotary evaporator to give a crude product. Methylene chloride (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 five times with pure water (20 g). Triphenylsulfonium methyl sulfate (15 g) was added and stirred at room temperature for 2 hours. The organic layer was separated, and washed three times with 10% aqueous sodium carbonate solution (20 g) and eight times with pure water (20 g). The organic layer was separated and the solvent was distilled off with a rotary evaporator. The obtained crude product was purified by silica gel column chromatography to obtain the desired product (12.9 g) in a yield of 23%. It was confirmed from the results of NMR spectrum measurement that this substance is the desired substance. The results are shown below. ¹ H-NMR (400 MHz, CDCl 3) δ 7.82-7.66 (m, 15 H), 6
. 86 (brs, 1 H), 2.36-1.45 (m, 21 H).

[Examples 1 to 5 and Comparative Examples 1 to 5]
[Preparation of Photosensitive Resin Composition Solution]
Each component shown in Table 1 was mixed and dissolved in 100 parts by mass of the acid-reactive compound represented by the following formula to prepare a positive resist composition (in the table, each abbreviation has the following meaning) ). Moreover, the numerical value in () is a compounding quantity (mass part) with respect to 100 mass parts of high molecular weight bodies as an acid reactive compound. In the following Examples and Comparative Examples, an acid reactive compound having the following unit ratio (a: b: c) was used, but the present invention is not limited to this.

Each of A-1 to A-9 is a sulfonium salt represented by the following formula. A-1 to A-6 and A-9 are obtained by the above synthesis. A-7 and A-8 can be synthesized by known methods.

Each of B-1 and B-2 is sulfonium represented by the following formula. B-1 was synthesized according to International Publication No. 2011/93139, and B-2 was synthesized according to International Publication No. 2015/083264.

[Evaluation of photosensitive resin composition solution]
The above resist compositions were spin-coated on a silicon wafer by a spin coater, and then prebaked on a hot plate at 110 ° C. for 60 seconds to obtain a coated film having a thickness of 150 nm. The mask was used to obtain a 90 nm line pattern, and exposure was performed by an ArF excimer laser stepper (wavelength 193 nm), and PEB temperature was carried out at 110 ° C. for 90 seconds. Thereafter, development was carried out using a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds, and then rinsed with pure water for 30 seconds to obtain a patterned substrate.
The sensitivity, resolution, and line width roughness (LWR) at this time were based on the values of Comparative Example 1, and the sensitivities, resolutions of Examples 1 to 5 and Comparative Examples 2 to 5 when compared with the reference. Each performance of LWR was evaluated using the following as an index. A scanning electron microscope was used to measure the resist pattern.
<Indicator>
A: An improvement of 10% or more over Comparative Example 1 O: An improvement of 5% or more and 10% or less over Comparative Example 1 A: 0% or more over Comparative Example 1 In the case where an improvement of 5% or less is observed x: In the case of being inferior to Comparative Example

The evaluation items of sensitivity, resolution and LWR are defined as follows.
(sensitivity)
It is shown by the minimum exposure which reproduces a 90 nm line pattern. The sensitivity is better as the minimum exposure amount is smaller.
(resolution)
The width (nm) of the line pattern which can be resolved by the minimum exposure amount for reproducing the 90 nm line pattern, that is, the critical resolution is shown. The smaller the numerical value, the better the resolution.
(Line Wiz Sloughness: LWR)
The standard deviation (σ) is obtained by measuring 50 points of the gate length for the range of 2.5 μm of the longitudinal edge of the 90 nm line pattern obtained by the minimum exposure amount for reproducing the 90 nm line pattern, and its triple value (3σ ) Was calculated as LWR. As the value is smaller, the roughness is smaller and a uniform pattern is obtained, which is a good performance.

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

[Examples 6 to 7 and Comparative Examples 6 to 7]
In the same manner as in Example 1, a photosensitive resin composition solution was prepared, and the blending part was adjusted and evaluated so that the addition amount of the photodisintegrable base was equimolar ratio to that in Example 1.
The sensitivities, resolutions and LWRs of Examples 6 to 7 and Comparative Examples 6 to 7 in comparison with the reference using the value of Comparative Example 6 based on the sensitivity, resolution and LWR are as follows: Was evaluated as an indicator. A scanning electron microscope was used to measure the resist pattern.
<Indicator>
A: An improvement of 10% or more with respect to Comparative Example 6 O: An improvement of 5% or more and 10% or less with respect to Comparative Example 6 B: 0% or more with respect to Comparative Example 6 When an improvement of 5% or less is observed x: When inferior to Comparative Example 6 The evaluation results are shown in Table 4.

[Example 8]
10.0 parts by mass of the photoacid generator A-1 synthesized above, 100 parts by mass of the polymer of the above structure, and 0.2 parts by mass of triethanolamine are dissolved in 525 parts by mass of propylene glycol monomethyl ether acetate And filter through a PTFE filter to prepare a photoresist composition solution. Next, the photoresist composition solution is spin-coated on a silicon wafer, and then prebaked on a hot plate at 110 ° C. for 90 seconds to obtain a resist film with a film thickness of 300 nm. The film is exposed by an ArF excimer laser stepper (wavelength 193 nm) and then post-baked at 130 ° C. for 90 seconds. Thereafter, development is performed for 60 seconds in an aqueous solution of 2.38% tetramethylammonium hydroxide and rinsed with pure water for 30 seconds.

The resolution and LWR (Line Width Roughness) are evaluated in the same manner as in Example 1 and the like. In Example 8, each performance was evaluated using the following as an index, based on the resolution and LWR values when using the resist composition prepared in Comparative Example 9 below. A scanning electron microscope was used to measure the resist pattern.
<Indicator>
A: An improvement of 10% or more with respect to Comparative Example 9 O: An improvement of 5% or more and 10% or less with respect to Comparative Example 9 B: 0% or more with respect to Comparative Example 9 When an improvement of 5% or less is observed x: When inferior to Comparative Example 9, the results are shown in Table 5.

[Example 9]
A resist composition was prepared in the same manner as in Example 8 except that 10.8 parts by mass of the photoacid generator A-2 obtained above was used instead of using 10.0 parts by mass of the above photoacid generator A-1. The resist film is obtained, exposed, post-baked, and developed. The results obtained using the resist composition prepared in Comparative Example 9 in the same manner as Example 8 and based on the values of resolution and LWR are shown in Table 5.

Comparative Example 8

A resist composition was prepared in the same manner as in Example 8 except that 8.2 parts by mass of the photoacid generator A-6 obtained above was used instead of using 10.0 parts by mass of the above photoacid generator A-1 The resist film is obtained, exposed, post-baked, and developed. The results obtained using the resist composition prepared in Comparative Example 9 in the same manner as Example 8 and based on the values of resolution and LWR 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 above photoacid generator A1. The resist film is obtained, exposed, post-baked and developed. The results of Comparative Example 9 with respect to the resolution of the resist composition and LWR were used as a reference in Table 5.

The resolution and LWR in Table 5 indicate that the smaller the value, the better the effect.
From the above results, it can be seen that the photoacid generator in the present invention is excellent in the resolution in lithography and has the effect of being able to reduce the LWR in a fine pattern.

The sensitivity, resolution and LWR properties were excellent in Examples 1 to 7 in which a photosensitive resin composition solution was used by containing an onium salt compound having a specific structure as a photodisintegrable base. On the other hand, in Comparative Examples 1 to 7 using a photodisintegrable base containing no onium salt compound according to some aspects of the present invention, problems remain in the characteristics of sensitivity, resolution and LWR.
The resolution properties and LWR characteristics were excellent in Examples 8 to 9 in which a photosensitive resin composition solution was used by containing an onium salt compound having a specific structure as a photoacid generator. On the other hand, in Comparative Examples 8 to 9 using a photoacid generator which does not contain the onium salt compound according to some aspects of the present invention, problems remain in the properties of resolution and LWR.
From the above results, it is understood that the resist composition containing the onium salt compound according to one aspect of the present invention as a photoacid generator has an effect of being excellent in resolution and capable of reducing LWR in a fine pattern in lithography. .
The above effects are considered to be due to the fact that the photodisintegrable base in the present invention has an amide structure which is a highly polar atomic group in the anion part, which has a high diffusion control effect on acid diffusion. .

Since the resist composition which is one aspect of the present invention contains a photoacid generator having appropriate acid strength, the undecomposed onium salt compound acts as an acid diffusion control agent in the unexposed area and the exposed area, In the exposed area, secondary electrons can be generated by ionization, and generation of an acid from the photoacid generator can be improved, so that resolution in lithography is excellent and LWR (Line Width Roughness) in a fine pattern is reduced. it can.

Claims

The photo-acid generator containing the onium salt compound represented by following formula (1).

(In the formula (1), each of R 1 and R 2 independently represents a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; a substituent A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have a substituent; an aryl group having 5 to 30 carbon atoms which may have a substituent; and Optionally selected from the group consisting of optionally substituted heteroaryl groups having 3 to 30 carbon atoms, at least one of which is not a hydrogen atom,
When R 1 and R 2 have a methylene group, at least one methylene group in R 1 and R 2 may be substituted with a divalent hetero atom-containing group,
The R 1 and R 2 are bonded to each other via a single bond directly or via 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 You may form a ring structure with a nitrogen atom,
L is a divalent linking group represented by-(CF 2 ) n-
n is an integer of 1 or more,
M + is a monovalent onium cation. )
The photoacid generation according to claim 1, wherein the M + is an onium cation having any atom selected from the group consisting of sulfur (S), iodine (I), selenium (Se) and tellurium (Te). Agent.
The photoacid generator according to claim 2, wherein the M + is either a sulfonium 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 comprising the photoacid generator according to any one of claims 1 to 4.
The resist composition according to claim 5, further comprising an acid reactive compound.
The acid-reactive compound is at least one selected from the group consisting of a compound having a protecting group which is deprotected by an acid, a compound having a polymerizable group which is polymerized by an acid, and a crosslinking agent having a crosslinking action by an acid. The resist composition according to claim 6.
Forming a resist film on a substrate using the resist composition according to any one of claims 5 to 7;
Exposing the resist film using active energy rays;
And b. Developing the exposed resist film.
Ionic compound a compound represented by the following formula (2) M + X - in salt exchanged, method of manufacturing the onium salt compound comprising the step of obtaining an onium salt compound represented by the following formula (1).

(In the formula (1), each of R 1 and R 2 independently represents a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; a substituent A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have a substituent; an aryl group having 5 to 30 carbon atoms which may have a substituent; and Optionally selected from the group consisting of optionally substituted heteroaryl groups having 3 to 30 carbon atoms, at least one of which is not a hydrogen atom,
When R 1 and R 2 have a methylene group, at least one methylene group in R 1 and R 2 may be substituted with a divalent hetero atom-containing group,
The R 1 and R 2 are bonded to each other via a single bond directly or via 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 You may form a ring structure with a nitrogen atom,
L is a divalent linking group represented by-(CF 2 ) n-
n is an integer of 1 or more,
M + is a monovalent onium cation.
In the formula (2), R 1, R 2 and L is selected from the same options as R 1, R 2 and L in the formula (1),
Q + is a monovalent cation other than M + in the formula (1),
M + X - of M + is the same as the M + of the formula (1), X - is a monovalent anion. )
The production method according to claim 9, wherein the M + is an onium cation having any atom selected from the group consisting of sulfur (S), iodine (I), selenium (Se) and tellurium (Te).
The method according to claim 10, wherein the M + is either a sulfonium 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 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), each of R 3 to R 6 independently represents a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; a substituent A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have a substituent; an aryl group having 5 to 30 carbon atoms which may have a substituent; and Optionally selected from the group consisting of optionally substituted heteroaryl groups having 3 to 30 carbon atoms, at least one of which is not a hydrogen atom,
When R 3 to R 6 have a methylene group, at least one methylene group in R 3 to R 6 may be substituted with a divalent hetero atom-containing group,
Two of R 3 to R 6 are a single bond directly or via 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, They may form a ring structure with the nitrogen atom to which they are attached. )
A salt represented by the following formula (2) which is useful 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. Compound.

(Wherein (2), R 1, R 2 and L is selected from the same options as R 1, R 2 and L in the formula (1),
Q + is a monovalent cation other than M + in the formula (1). )
The salt compound according to claim 14, wherein the Q + is an ammonium cation represented by the following formula (3).

(In the formula (3), each of R 3 to R 6 independently represents a hydrogen atom; a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms which may have a substituent; a substituent A linear, branched or cyclic alkenyl group having 2 to 30 carbon atoms which may have a substituent; an aryl group having 5 to 30 carbon atoms which may have a substituent; and Optionally selected from the group consisting of optionally substituted heteroaryl groups having 3 to 30 carbon atoms, at least one of which is not a hydrogen atom,
When R 3 to R 6 have a methylene group, at least one methylene group in R 3 to R 6 may be substituted with a divalent hetero atom-containing group,
Two of R 3 to R 6 are a single bond directly or via 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, They may form a ring structure with the nitrogen atom to which they are attached. )
L is - (CF 2) 2 - or - (CF 2) 3 - salt compound according to claim 14 or 15 is.