JP2020176096A - Onium salt, composition, and device manufacturing method using the same - Google Patents

Abstract

To provide a photoacid generator for a chemically amplified resist simultaneously satisfying characteristics of sensitivity, resolution and pattern performance.SOLUTION: An onium salt is represented by one selected from general formulas (1) and (2). (R11 and R12 are each an alkyl group, alkenyl group, aryl group, or the like; R13 and R14 are each an alkyl group, hydroxy group, alkoxy group, or the like; R15 and R16 are each an alkyl group, alkenyl group, aryl group, or the like; L1 is a direct bond, alkylene group, alkenylene group, arylene group, or the like; L4 and L5 are each a direct bond, alkenylene group, alkynylene group, or carbonyl group; Y is an oxygen or sulfur atom; h and i are each an integer from 1 to 3; j is an integer from 0 to 4 if h is 1, from 0 to 6 if h is 2, and from 0 to 8 if h is 3; k is an integer from 0 to 5 if i is 1, from 0 to 7 if i is 2, and from 0 to 9 if i is 3; X- represents a monovalent counter anion; and R17 is an aryl group or heteroaryl group.)SELECTED DRAWING: None

Description

One aspect of the present invention relates to onium salts. Another aspect of the present invention relates to a composition containing the onium salt and a method for producing a device using the composition.

In recent years, the manufacture of display devices such as liquid crystal displays (LCDs) and organic EL displays (OLEDs) and the formation of semiconductor elements have been actively carried out by making full use of photolithography technology using photoresists. Light having a wavelength of 365 nm, h-rays (405 nm) and g-lines (436 nm) having a wavelength longer than that is widely used as active energy rays in the above-mentioned electronic parts and packages of electronic products.

With the increasing integration of devices, the demand for miniaturization of lithography technology is increasing, such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), extreme ultraviolet (EUV, wavelength 13.5 nm) and electron beam (wavelength 13.5 nm). Light and particle beams with very short wavelengths, such as EB), tend to be used for exposure. Since the lithography technique using light having a short wavelength, particularly EUV or electron beam, can be manufactured by single patterning, there is a need for a resist composition showing high sensitivity to EUV or electron beam or the like. It is expected to increase further in the future.

As the wavelength of the exposure light source is shortened, the resist composition is required to have improved sensitivity to the exposure light source and lithographic characteristics of resolvability capable of reproducing a pattern of fine dimensions. A chemically amplified resist is known as a resist composition satisfying such a requirement (Patent Document 1).
However, the conventional chemically amplified resist composition for EUV or electron beam has a small absorption of EUV or electron beam, and it is difficult to simultaneously satisfy the characteristics of sensitivity, resolution and pattern performance. In particular, it is possible to overcome the decrease in throughput due to low sensitivity due to the small absorption, and the deterioration of resist pattern collapse and line pattern linewise roughness (LWR) that occur as the resolution line width of the resist becomes finer. difficult.

To solve the above problems, after generating an acid and a sensitizer by lithography using first active energy rays such as EUV or electron beam for the purpose of improving the throughput of EUV or electron beam lithography, visible light or ultraviolet rays, etc. A photosensitizing chemical amplification resist composition for irradiating the second active energy ray of the above has been proposed. (Patent Documents 2 to 3 and Non-Patent Document 1)

Japanese Unexamined Patent Publication No. 9-90637 Japanese Patent No. 5881093 Japanese Unexamined Patent Publication No. 2015-172741

Proc. of SPIE Vol. 9776 9777607

However, when the resist reaction is promoted by the second active energy ray using the photosensitizing chemical amplification resist composition utilizing the photosensitizing reaction, the sensitizer (electron donor) and the photoacid generator ( Since the photo-induced electron transfer reaction that occurs with the electron acceptor) is used, an acid may be generated even by an electron transfer reaction of several nm in some cases. This may cause unintended diffusion of generated acid without reacting with the acid diffusion control agent even when the acid diffusion control agent is contained in the resist composition. As a result, pattern deterioration such as deterioration of LWR may occur. On the other hand, when a large amount of acid diffusion control agent is added to suppress pattern deterioration, the amount of photosensitizer produced is increased in the process of producing a photosensitizer by the action of the acid generated by the first active energy ray. Since the amount is small, the sensitization reaction is unlikely to occur, and there is a problem that the effect of promoting the resist reaction is slight even when a large amount of energy of 1 J / cm ² is irradiated.

In view of such circumstances, it is an object of some aspects of the present invention to provide a photoacid generator and a composition having excellent sensitivity and pattern characteristics such as LWR. More specifically, it is an object of the present invention to provide an optimum onium salt as a photoacid generator used when irradiating particle beams or electromagnetic waves. Another object of the present invention is to provide a composition containing the onium salt and a specific resin whose solubility in a developing solution is changed by the action of an acid.
Another object of the present invention is to provide an optimal onium salt as a photoacid generator used when exposing a second active energy ray such as ultraviolet light or visible light after irradiation with a first active energy ray such as an electron beam or extreme ultraviolet light. To do. Another object of the present invention is to provide a photoacid generator containing the onium salt and a composition containing the photoacid generator. Another object of the present invention is to provide a method for manufacturing a device using the composition.

As a result of diligent studies to solve the above problems, the present inventors have not significantly absorbed the second active energy ray such as ultraviolet rays or visible light, and the onium salt having a specific structure does not have remarkable absorption. It has been found that the structural change due to the acid generated by the first active energy ray, such as having a shorter wavelength than the active energy ray, is converted into a ketone derivative having absorption in the second active energy ray, and some embodiments of the present invention. Has been completed.
More specifically, the present inventors have found that having at least one amino group or heterocyclic structure at a specific site of an onium salt has high absorption for the second active energy and excellent acid generation efficiency. , Have completed some aspects of the present invention.
By using the photoacid generator containing the onium salt in the resist composition, the resist composition described in Patent Document 3 which uses the photosensitization reaction generated between the electron donor and the electron acceptor is compared with the resist composition. It has been found that since the acid is generated with high efficiency by the two active energy rays, it is excellent in high sensitivity and pattern characteristics such as LWR.

One aspect of the present invention for solving the above problems is an onium salt represented by any of the following general formula (1) and the following general formula (2).

In the above formula (1), R ¹¹ and R ¹² each have a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; which may independently have a substituent; It may have a linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and may have a substituent. It is one selected from the group consisting of good heteroaryl groups having 4 to 12 carbon atoms;
Any two or more of the above R ¹¹ , R ¹² and the aryl group to which the sulfonium group is bonded are selected directly by a single bond or from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. A ring structure may be formed together with the sulfur atom to which they are bonded via any of the above.
At least one methylene group in R ¹¹ and R ¹² may be substituted with a divalent heteroatom-containing group.

R ¹³ and R ¹⁴ independently have an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, respectively. Alkyl sulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, (meth) acryloyloxy group, hydroxy (poly) alkyleneoxy group, amino group, cyano It is one selected from the group consisting of a group, a nitro group, and a halogen atom, and when it has carbon, the number of carbon atoms is 1 to 12, and these may have a substituent.
At least one of the above R ^14s is an amino group, or R ¹⁴ is selected from the group consisting of oxygen atom, sulfur atom and nitrogen atom-containing group together with an aryl group to which the R ¹⁴ is attached. They form heterocyclic structures with each other.

R ¹⁵ and R ¹⁶ are linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, each of which may independently have a substituent; and may have a substituent. A branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and an aryl group having 4 to 12 carbon atoms which may have a substituent. Heteroaryl group; any one selected from the group consisting of.
The R ¹⁵ and R ¹⁶ may be bonded to each other directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and an alkylene group to form a ring structure.
At least one methylene group in R ¹⁵ and R ¹⁶ may be substituted with a divalent heteroatom-containing group.

L ¹ is a direct bond; a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 1 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; a carbon atom number of 4 to 12 It is any one selected from the group consisting of heteroarylene groups; and groups in which these groups are bonded via an oxygen atom, a sulfur atom or a nitrogen atom-containing group;
L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group.

Y is an oxygen atom or a sulfur atom.
h and i are independently integers 1 to 3 respectively.
j is an integer of 0 to 4 when h is 1, 0 to 6 when h is 2, and 0 to 8 when h is 3.
k is an integer of 0 to 5 when i is 1, 0 to 7 when i is 2, and 0 to 9 when i is 3.
X ⁻ represents a monovalent counter anion.

In the above formula (2), R ^{11 to} R ¹⁶ , L ¹ , L ^{4 to} L ⁵ , Y, h to k, and X ⁻ are independently each of R ^{11 to} R ¹⁶ , L in the above formula (1). ^{1, L 4 ~L 5, Y} , h~k and X ^- is selected from the same options with each.
R ¹⁷ is one selected from the group consisting of an aryl group which may have a substituent; and a heteroaryl group which may have a substituent, and R ¹⁷ and an iodonium group are bonded to each other. Aryl groups may be bonded to each other to form a ring structure with iodine atoms to which they are bonded.

Further, one aspect of the present invention is the onium salt represented by the following general formula (3). Although monocations are shown below, they may be polycations.

In the above formula (3), R ^{13 to} R ¹⁶ , Y and X ⁻ are independently selected from the same options as those of R ^{13 to} R ¹⁶ , Y and X ⁻ in the above formula (1).
R ¹⁸ is an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an alkylsulfanyl group, an arylsulfanyl group, an aryl group, or a hetero. From aryl groups, aryloxy groups, alkylsulfinyl groups, arylsulfinyl groups, alkylsulfonyl groups, arylsulfonyl groups, (meth) acryloyloxy groups, hydroxy (poly) alkyleneoxy groups, amino groups, cyano groups, nitro groups and halogen atoms The number of carbon atoms in the case of having carbon is 1 to 12, and these may have substituents.

L ² and L ³ are each independently selected from the group consisting of a direct bond; a methylene group; an oxygen atom; a sulfur atom; a nitrogen atom-containing group;
The methylene group may have a substituent, and one of L ² and L ³ is either an oxygen atom, a sulfur atom, or a nitrogen atom-containing group.
e is an integer from 0 to 4, and f is an integer from 0 to 3. g is an integer from 0 to 4.

In addition, another aspect of the present invention is a photoacid generator containing at least an onium salt represented by any of the above general formula (1) and the above general formula (2) (hereinafter, "photoacid generator"). (A) "is also called"). The photoacid generator (A) generates an acid upon exposure.

One aspect of the present invention for solving the above-mentioned problems is a composition containing the above-mentioned photoacid generator (A) and an acid-reactive compound.

Preferably, the composition further comprises an acid diffusion control agent.

Preferably, the acid-reactive compound is a resin (B) whose solubility in a developing solution changes due to the action of an acid.
The resin (B) is a composition having at least one of the units represented by the following (4a) to (4d). Although the onium salt contained in the photoacid generator (A) shows a monocation in the above, it may be a polycation.

In the above formulas (4a) to (4d), R ¹ is any one selected from the group consisting of a hydrogen atom, an alkyl group and an alkyl halide group.
R ² and R ³ are independently linear, branched or cyclic alkyl groups, respectively.
R ⁴ is a linear, branched or cyclic alkyl group which may have a substituent.
Two or more of the above R ² , R ³ and R ⁴ are either directly in a single bond or selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. , A ring structure may be formed.
L ⁶ is selected from the group consisting of a direct bond, a carbonyloxy group, a carbonylamino group, a linear, branched or cyclic alkylenecarbonyloxy group which may have a substituent, and an alkylenecarbonylamino group. Is.

In the above formula (4b), R ¹ and L ⁶ are selected from the same options as each of the above formula (4a) R ¹ and L ⁶ .
R ⁵ and R ⁶ are each independently selected from the group consisting of a hydrogen atom and a linear, branched or cyclic alkyl group.
R ⁷ is a linear, branched or cyclic alkyl group which may have a substituent.
Two or more of the above R ⁵ , R ⁶ and R ⁷ are either directly in a single bond or selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. A ring structure may be formed.

In the above formula ^(4c), R 1 ~R ⁴ and ^{L 6} are selected from the same options as each of ^R 1 to R ⁴ and ^{L 6} in the above formula (4a).
R ⁸ independently consists of a group consisting of an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an alkylsulfanyl group, an alkylsulfinyl group, an alkylsulfonyl group, an amino group, a cyano group, a nitro group, and a halogen atom. It is one of the choices.
Two or more of R ⁸ is a direct single bond or an oxygen atom, a sulfur atom, via any one selected from the group consisting of nitrogen atom-containing group and a methylene group, to form a ring structure Good.
l is an integer of 1-2.
m is an integer of 0 to 4 when l is 1 and 0 to 6 when l is 2.
n is an integer of 1 to 5 when l is 1 and 1 to 7 when l is 2.
m + n is 1 to 5 when l is 1, and 1 to 7 when l is 2.

In the above formula ^{(4d), R 1, R} 5 ~R 7, R 8, L 6, l and ^{n, R} 1, ^{R 5} ~R 7 in the formula ^{(4a) ~ (4c),} R 8, L It is selected from the same options as each of ⁶ , l and n.

In addition, another aspect of the present invention includes a step of applying the above composition on a substrate to form a resist film, a step of irradiating the resist film with the first active energy ray, and after the first active energy ray irradiation. This is a method for manufacturing a device, which includes a step of irradiating the resist film of No. 2 with a second active energy ray and a step of developing the resist film after the irradiation of the second active energy ray to obtain a pattern.

According to some aspects of the present invention, it is suitably used as a resist composition for a lithography process using a first active energy ray such as a particle beam or an electromagnetic wave and a second active energy ray such as ultraviolet light or visible light. , It is possible to provide an onium salt having high sensitivity and excellent pattern characteristics such as LWR. Further, a resist composition containing the onium salt as an acid generator and having high sensitivity to first active energy such as particle beam or electromagnetic wave, particularly electron beam or extreme ultraviolet light, and a method for manufacturing a device using the resist composition. Can be provided.

FIG. 1 shows a UV absorption spectrum.

Hereinafter, the present invention will be specifically described, but the present invention is not limited thereto.
<1> Onium salt and photoacid generator The onium salt according to one aspect of the present invention is represented by any one selected from the above general formula (1) and the above general formula (2). In addition, the photoacid generator (A) contains at least one of the onium salts. The onium salt is a sulfonium salt or an iodonium salt.

The onium salt according to one aspect of the present invention has a specific structure such as acetal or thioacetal, and thus does not have significant absorption by the second active energy ray such as ultraviolet rays or visible light. On the other hand, the acetal of the onium salt or the acetal of the onium salt without impairing the function as a photoacid generator by the acid generated by the first active energy ray such as a particle beam or an electromagnetic wave, particularly an electron beam or an extreme ultraviolet ray. Thioacetal is deprotected and converted to a ketone derivative. The ketone derivative has absorption in the first active energy ray and the second active energy ray. Since the ketone derivative is generated in the exposed portion irradiated with the first active energy ray in the resist film, the amount of acid generated in the exposed portion by the first active energy ray by further irradiating the second active energy ray. Can be increased.
Further, the onium salt according to one aspect of the present invention has at least one amino group or a heterocyclic structure at a specific site, so that it has high absorption for the second active energy and is excellent in acid generation efficiency.

In the above formula (1), R ¹¹ and R ¹² each have a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; which may independently have a substituent; It may have a linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and may have a substituent. Any one selected from the group consisting of good heteroaryl groups having 4 to 12 carbon atoms; is preferable.

Specific examples of the linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms in R ¹¹ and R ¹² are methyl, ethyl, n-propyl, n-butyl, isopropyl, t-butyl and cyclo, respectively. Examples thereof include alkyl groups such as propyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, adamantan-1-yl group, adamantan-2-yl group, norbornan-1-yl group and norbornan-2-yl group.

In the alkyl groups of R ¹¹ and R ¹² , instead of at least one methylene group, -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH- , -NH-CO-O-, -O-CO-NH-, -NH-, -N (R)-, -N (Ar)-, -S-, -SO- and -SO _2- The skeleton may contain one divalent heteroatom-containing group selected from the above. However, it is preferable that the sulfur atom (S ⁺ ) of the sulfonium group is not directly bonded to the heteroatom-containing group but is bonded to the divalent hydrocarbon group. R and Ar will be described later.
Examples of the alkenyl groups of R ¹¹ and R ¹² include those in which at least one carbon-carbon single bond of the above alkyl group is replaced with a carbon-carbon double bond.

Specific examples of the aryl group having 6 to 14 carbon atoms which may have a substituent of R ¹¹ and R ¹² include a monocyclic aromatic hydrocarbon group and at least 2 monocyclic aromatic hydrocarbons. Examples thereof include ring-condensed condensed polycyclic aromatic hydrocarbon groups. These aryl groups may have a substituent.
Examples of the monocyclic aromatic hydrocarbon group include a group having a skeleton such as benzene.
Examples of the fused polycyclic aromatic hydrocarbon group include groups having a skeleton such as indene, naphthalene, azulene, anthracene and phenanthrene.

The heteroaryl group having 4 to 12 carbon atoms which may have a substituent of R ¹¹ and R ¹² is selected from an oxygen atom, a nitrogen atom and a sulfur atom in place of at least one carbon atom of the above aryl group. The skeleton contains at least one of the above.

The heteroaryl group includes a monocyclic aromatic heterocyclic group, and a condensed polycyclic aromatic heterocycle in which at least one of the monocyclic aromatic heterocycles is condensed with the aromatic hydrocarbon group, the aliphatic heterocyclic group, or the like. Ring groups and the like can be mentioned. These aromatic heterocyclic groups may have a substituent.
Examples of the monocyclic aromatic heterocyclic group include groups having a skeleton such as furan, pyrrole, imidazole, pyran, pyridine, pyrimidine and pyrazine.

Examples of the fused polycyclic aromatic heterocyclic group include groups having a skeleton such as indole, purine, quinoline, isoquinoline, chromene, phenoxazine, xanthene, acridine, phenazine and carbazole.

Examples of the substituent (hereinafter, also referred to as “first substituent”) that R ¹¹ and R ¹² may have include a hydroxy group, a cyano group, a mercapto group, a carboxy group, a carbonyl group, an alkyl group (-R), and the like. Alkoxy group (-OR), acyl group (-COR), alkoxycarbonyl group (-COOR), aryl group (-Ar), aryloxy group (-OAr), amino group, alkylamino group (-NHR), dialkylamino group (-N (R) ₂ ), arylamino group (-NHAr), diarylamino group (-N (Ar) ₂ ), N-alkyl-N-arylamino group (-NRAr) phosphino group, silyl group, halogen atom , Trialkylsilyl group (-Si- (R) ₃ ), silyl group in which at least one of the alkyl groups of the trialkylsilyl group is substituted with Ar, alkylsulfanyl group (-SR) and arylsulfanyl group (-SAR). Etc., but are not limited to these. R and Ar will be described later.

Further, as the first substituent, the group may be a group having a polymerizable group such as a (meth) acryloyl group.

Any two or more of the above R ¹¹ and R ¹² and the aryl group to which the sulfonium group is bonded are selected directly by a single bond or from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. A ring structure may be formed together with the sulfur atom (S ⁺ ) of the sulfonium group to which they are bonded via any of the above. However, it is preferable that the sulfur atom (S ⁺ ) of the sulfonium group is not directly bonded to the heteroatom-containing group but is bonded to the divalent hydrocarbon group.
Examples of the above-mentioned "nitrogen atom-containing group" include divalent groups containing a nitrogen atom such as an aminodiyl group (-NH-), an alkylaminodiyl group (-NR-) and an arylaminodiyl group (-NAr-). Be done. R and Ar will be described later.
In the above formula (1), the aryl group to which the sulfonium group is bonded is the portion indicated by the arrow below.

The R in the first substituent and the like is preferably an alkyl group having 1 or more carbon atoms. Further, it is more preferable that the number of carbon atoms is 20 or less. Specific examples of alkyl groups having one or more carbon atoms include, for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group and n-decyl. Linear alkyl groups such as groups; branched alkyl groups such as isopropyl group, isobutyl group, tert-butyl group, isopentyl group, tert-pentyl group, 2-ethylexyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl Alicyclic alkyl groups such as groups, adamantan-1-yl groups, adamantan-2-yl groups, norbornan-1-yl groups and norbornan-2-yl groups; one of these hydrogens is a trimethylsilyl group, a triethylsilyl group and Preferred examples thereof include a silyl group-substituted alkyl group substituted with a trialkylsilyl group such as a dimethylethylsilyl group; an alkyl group in which at least one of these hydrogen atoms is substituted with a cyano group, a fluoro group or the like; and the like. The carbon-carbon single bond in the alkyl group may be replaced with a carbon-carbon double bond.

Ar in the first substituent and the like is preferably an aryl group or a heteroaryl group. The heteroaryl group is an aryl group containing one or more heteroatoms in the ring structure. Specific examples of the above Ar include a phenyl group, a biphenyl group, a terphenyl group, a quaterphenyl group, a naphthyl group, an anthryl group, a phenanthrenyl group, a pentarenyl group, an indenyl group, an indasenyl group, an acenaphthyl group, a fluorenyl group and a heptalenyl group. Naphthalsenyl group, pyrenyl group, chrysenyl group, tetrasenyl group, phenylyl group, thienyl group, pyranyl group, sulfanylpyranyl group, pyrrolyl group, imidazolyl group, oxazolyl group, thiazolyl group, pyrazoyl group, pyridyl group, isobenzofuranyl group , A benzofuranyl group, an isochromenyl group, a chromenyl group, an indolyl group, an isoindrill group, a benzoimidazolyl group, a xanthenyl group, an aquazinyl group, a carbazoyl group and the like having 20 or less carbon atoms are preferable.
When R ¹¹ and R ¹² have the first substituent and the onium salt is a low molecular weight compound, the number of carbon atoms of R ¹¹ and R ¹² includes the number of carbon atoms of the first substituent. It is preferably 1 to 20.

The onium salt in one embodiment of the present invention may be a polymer component bonded to a part of the polymer as one unit of the resin, that is, as a unit containing an onium salt structure, or as a unit of the polymer. It may be a polymer component contained as. When it is a polymer component, the main chain of the polymer can be mentioned as the first substituent. When the first substituent of R ¹¹ and R ¹² is a main chain of the polymer, the carbon atom number of R ¹¹ and R ¹² and minus the number of carbon atoms of the polymer backbone. When the onium salt in one embodiment of the present invention is a polymer component, it is preferable to adjust the weight average molecular weight of the entire polymer component to be 2000 to 200,000.
In the present invention, the low molecular weight compound has a weight average molecular weight of less than 2000, and the polymer component has a weight average molecular weight of 2000 or more.

As R ¹¹ and R ¹² , aryl groups are preferable from the viewpoint of improving stability.

R ¹³ and R ¹⁴ independently have an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, respectively. Alkyl sulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, arylsulfonyl group, (meth) acryloyloxy group, hydroxy (poly) alkyleneoxy group, It is any one selected from the group consisting of an amino group, a cyano group, a nitro group and a halogen atom, and when it has carbon, the number of carbon atoms is preferably 1 to 12, and these are substituents (hereinafter, "second"). It may also have a "substituted group"). Further, the carbon-carbon single bond in the alkyl group of R ¹³ and R ¹⁴ may be replaced with a carbon-carbon double bond.
Examples of the second substituent that R ¹³ and R ¹⁴ may have include the same as the first substituent.
When R ¹³ and R ¹⁴ have the above second substituent and the onium salt is a low molecular weight compound, the number of carbon atoms of R ¹³ and R ¹⁴ includes the number of carbon atoms of the second substituent. It is preferably 1 to 12. When the second substituent of R ¹³ and ^{R 14} is a polymer main ^chain, the carbon atoms of ^{R 13} and ^{R 14} and minus the polymer backbone.

However, in the onium salt according to one aspect of the present invention, at least one of R ¹⁴ is an amino group, or R ¹⁴ is selected from the group consisting of an oxygen atom, a sulfur atom and a nitrogen atom-containing group. A heterocyclic structure is formed with the aryl group to which the R ¹⁴ is attached.
A preferred onium salt, which is one embodiment of the present invention, is such that at least one of R ¹⁴ is an amino group, or R ¹⁴ is heterocyclic with each other together with an aryl group to which the R ¹⁴ is attached via a nitrogen atom-containing group. It forms a structure.
Further preferred onium salt is one aspect of the present invention is one in which R ¹⁴ is to form a hetero ring system with one another with an aryl group wherein R ¹⁴ is bonded through a nitrogen atom-containing group. Examples of the nitrogen atom-containing group include a divalent group such as −N (H) − or a trivalent group such as = N−, and the hydrogen atom may be substituted with the second substituent.
With the above configuration of R ¹⁴ , when the acetal group or the thioacetal group is deprotected and converted into a ketone derivative, it becomes absorbed by the second active energy ray such as ultraviolet rays or visible light.
Hereinafter, R ¹⁴ which is an amino group is referred to as “R ^14a ”, and the other R ¹⁴ is also referred to as “R ^14b ”.

The alkyl group in R ¹³ and R ^14b may be a straight chain, a branched chain or a cyclic group, and specific examples thereof include the same alkyl group as the R alkyl group as the first substituent. ^Examples of the aryl group and heteroaryl group in R ¹³ and R ^14b include those similar to the aryl group and heteroaryl group of Ar as the first substituent of R ¹¹ and R ¹² . Examples of the alkoxy group in R ¹³ and R ^14b include those similar to the alkoxy group (-OR) in the first substituent.
^Examples of the hydroxy (poly) alkyleneoxy group in R ¹³ and R ^14b include a polyethylene oxy group and a polypropylene oxy group.
Examples of the halogen atom in R ¹³ and R ^14b include a fluorine atom, a chlorine atom, an iodine atom and the like.

In the alkyl group in R ¹³ and R ^14b , instead of at least one methylene group, the same group as the hetero atom-containing group in R ¹¹ and R ¹² may be contained in the skeleton. However, it is preferable not to have a continuous connection of heteroatoms such as -O-O-, -S-S- and -O-S-.
The R ^14b is preferably an alkyl group. Further, when the ortho or para to the quaternary carbon bonded to an arylene with Y and R ^14, an aryl group, an alkoxy group, an alkylsulfanyl group, an aryloxy group, an aryl sulfanyl group, an amino group and alkylamino An electron donating group such as a group is also preferably mentioned. These are preferable from the viewpoint of improving the absorbance at 365 nm.

A linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may have a substituent as R ¹⁵ and R ¹⁶ ; a linear, branched or cyclic carbon atom which may have a substituent. Alkyl groups of numbers 1 to 12; aryl groups having 6 to 14 carbon atoms which may have a substituent; and heteroaryl groups having 4 to 12 carbon atoms which may have a substituent; Preferably, they are selected from the same options as each of R ¹¹ and R ¹² above.
Examples of the substituents as R ¹⁵ and R ¹⁶ (hereinafter, also referred to as “third substituent”) are the same as those of the first substituent.
The R ¹⁵ and R ¹⁶ may be bonded to each other directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and an alkylene group to form a ring structure.
From the viewpoint of synthesis, it is preferable that R ¹⁵ and R ¹⁶ are the same.

L ¹ is a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 1 to 12 carbon atoms; an arylene group having 6 to 12 carbon atoms; a heteroarylene group having 4 to 12 carbon atoms. It is preferable that any of these groups is selected from the group consisting of; and a group in which these groups are bonded via an oxygen atom, a sulfur atom or a nitrogen atom-containing group; Examples of the alkylene group, alkenylene group, arylene group and heteroarylene group of L ¹ include those in which the alkyl group, alkenyl group, aryl group and heteroaryl group of R ¹¹ are divalent. Examples of the nitrogen atom-containing group of L ¹ are the same as those of the nitrogen atom-containing group of R ¹¹ .
When L ¹ is "a group in which these groups are bonded via an oxygen atom, a sulfur atom or a nitrogen atom-containing group", any one of the above-mentioned alkylene group, alkenylene group, arylene group and heteroarylene group is oxygen. This is the case where the sulfonium group is bonded to an aryl group to which the sulfonium group is bonded via an atom, a sulfur atom or a nitrogen atom-containing group.
In the above general formula (1), k and j are preferably 0 to 3 independently, and more preferably 0 to 2 independently, from the viewpoint of ease of synthesis. ..

In the above general formula (2), R ^{13 to} R ¹⁶ , X ⁻ , Y, L ¹ , L ^{4 to} L ⁵ , and h to k are independently R ^{13 to} R ¹⁶ and X in the above formula (1), respectively. ^- , Y, L ¹ , L ^{4 to} L ⁵ , and h to k are selected from the same options.

R ¹⁷ is preferably a 6 to 12 aryl group having a carbon atom number which may have a substituent; and a heteroaryl group having 4 to 12 carbon atoms which may have a substituent. R ¹⁷ and the aryl group to which the iodonium group is bonded may be bonded to each other to form a ring structure together with the iodine atom to which they are bonded. The aryl group and heteroaryl group of R ¹⁷ are selected from the same options as the aryl group and heteroaryl group of R ¹¹ above, respectively. Examples of the substituent in R ¹⁷ include the same as the first substituent.
In the general formula (2), the aryl group to which the iodonium group is bonded is the portion indicated by the arrow below.

L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group. That is, the quaternary carbon atom in which two Ys are directly bonded and the two aryl groups may be directly bonded, and are bonded via an alkenylene group having 2 carbon atoms or an alkynylene group having 2 carbon atoms. However, it is a structure containing at least one bond via an alkenylene group having 2 carbon atoms or an alquinylene group having 2 carbon atoms.

L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group. That is, the quaternary carbon atom in which two Ys are directly bonded and the two aryl groups may be directly bonded, and are bonded via an alkenylene group having 2 carbon atoms or an alkynylene group having 2 carbon atoms. However, it is a structure containing at least one bond via an alkenylene group having 2 carbon atoms or an alquinylene group having 2 carbon atoms.

In the above formula (1) or (2), Y is an oxygen atom or a sulfur atom.
h and i are independently integers 1 to 3 respectively.
j is an integer of 0 to 4 when h is 1, 0 to 6 when h is 2, and 0 to 8 when h is 3.
k is an integer of 0 to 5 when i is 1, 0 to 7 when i is 2, and 0 to 9 when i is 3.
For example, when i and / or h is 2 in the above formula (1) or (2), the onium salt has a naphthalene ring. The naphthalene ring may be bonded to the quaternary carbon to which Y is bonded at any position from the 1st to 8th positions.
Further, for example, when i and / or h is 3 in the above formula (1) or (2), the onium salt has at least one of an anthracene ring, a phenanthrene ring, and a naphthacene ring. In this case as well, the phenanthrene ring and the naphthacene ring may be bonded to the quaternary carbon to which Y is bonded at any position at the 1st to 10th positions.

In some aspects of the present invention, examples of onium salts include those having a sulfonium cation and an iodonium cation shown below. However, some aspects of the invention are not limited to this.

One aspect of the present invention is preferably a sulfonium salt represented by the following formula (3). It is also preferable to use an iodonium salt which is an iodonio group instead of the sulfonio group in the following formula (3). Specific examples of the iodonio group include −I ⁺ R ¹⁷ in the above formula (2).

In the above formula (3), R ^{13 to} R ¹⁶ , Y and X ⁻ are independently selected from the same options as those of R ^{13 to} R ¹⁶ , Y and X ^{− in} the above formula (1), respectively.

R ¹⁸ is an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, an alkylsulfanyl group, an aryl group, or a heteroaryl. Groups, aryloxy groups, alkylsulfinyl groups, arylsulfinyl groups, alkylsulfonyl groups, arylsulfonyl groups, arylsulfonyl groups, (meth) acryloyloxy groups, hydroxy (poly) alkyleneoxy groups, amino groups, cyano groups, nitro groups and It is one selected from the group consisting of halogen atoms, and when it has carbon, the number of carbon atoms is preferably 1 to 12, and these may have a substituent. Carbon in the alkyl group R ¹⁸ - carbon single bond is a carbon - may be replaced by carbon-carbon double bond.

L ² and L ³ are independently selected from the group consisting of a direct bond; a methylene group; an oxygen atom; a sulfur atom; a nitrogen atom-containing group; and the methylene group has a substituent. However, either one of L ² and L ³ may be either an oxygen atom, a sulfur atom, or a nitrogen atom-containing group. A preferred embodiment of the above formula (3) is a case where L ² is a direct bond and L ³ is a nitrogen atom-containing group. Specifically, a preferred embodiment of the above formula (3) is when it has a carbazole skeleton.

e is an integer from 0 to 4, f is an integer from 0 to 4, and g is an integer from 0 to 5.

X ^- is an anion. The anion is not particularly limited, and examples thereof include anions such as sulfonic acid anion, carboxylic acid anion, imide anion, methide anion, carbo anion, borate anion, halogen anion, phosphate anion, antimonic acid anion, and arsenic acid anion.

More specifically, as an _{^{anion, ZA a-, (Rf) b}} PF (6-b) -, R 19 c BA (4-c) -, R 19 c GaA (4-c) -, R 20 SO 3 - , (R ²⁰ SO ₂ ) ₃ C ⁻ or (R ²⁰ SO ₂ ) ₂ N ⁻ anions are preferred. When two or more Rf, R ¹⁹ and R ²⁰ are possessed, the two Rf, the two R ^{19 and} the two R ²⁰ may be bonded to each other to form a ring.

Z represents a phosphorus atom, a boron atom or an antimony atom. A represents a halogen atom (preferably a fluorine atom).
P represents a phosphorus atom, F represents a fluorine atom, B represents a boron atom, and Ga represents a gallium atom.
S represents a sulfur atom, O represents an oxygen atom, C represents a carbon atom, and N represents a nitrogen atom.

Rf is preferably an alkyl group in which 80 mol% or more of hydrogen atoms are substituted with fluorine atoms, and the alkyl group is preferably an alkyl group having 1 to 8 carbon atoms. Alkyl groups to be Rf by fluorine substitution include linear alkyl groups (methyl, ethyl, propyl, butyl, pentyl, octyl, etc.), branched alkyl groups (isopropyl, isobutyl, sec-butyl, tert-butyl, etc.) and Cycloalkyl groups (cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc.) and the like can be mentioned. The ratio of hydrogen atoms of these alkyl groups substituted with fluorine atoms in Rf is preferably 80 mol% or more, more preferably 90, based on the number of moles of hydrogen atoms possessed by the original alkyl group. % Or more, particularly preferably 100%.

Particularly preferred Rf are CF ₃ ⁻ , CF ₃ CF ₂ ⁻ , (CF ₃ ) ₂ CF ⁻ , CF ₃ CF ₂ CF ₂ ⁻ , CF ₃ CF ₂ CF ₂ CF ₂ ⁻ , (CF ₃ ) ₂ CFCF ₂ ^−. , CF ₃ CF ₂ (CF ₃ ) CF ⁻ and (CF ₃ ) ₃ C ⁻ . The b Rfs are independent of each other and therefore may be the same or different from each other.

R ^19, a part of hydrogen atoms represents at least one halogen atom or a phenyl group substituted with an electron withdrawing group. Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom. Examples of the electron attracting group include a trifluoromethyl group, a nitro group and a cyano group. Of these, a phenyl group in which one hydrogen atom is replaced with a fluorine atom or a trifluoromethyl group is preferable. c number of R ¹⁹ is independently from each other, therefore, it may be the same or different from each other.

R ²⁰ represents an alkyl group having 1 to 20 carbon atoms in which a part or all of hydrogen atoms may be substituted with a fluorine atom, or an aryl group having 6 to 20 carbon atoms, and the alkyl group is a linear or fractional group. It may be branched or cyclic, and the aryl group may be unsubstituted or having a substituent.
a represents an integer of 4 to 6. b represents an integer of 1 to 5, preferably 2 to 4, particularly preferably 2 or 3. c represents an integer of 1 to 4, and is preferably 4.
Examples of the anion represented by ZA _a ⁻ include anions represented by SbF ₆ ⁻ , PF ₆ ⁻ and BF ₄ ⁻ .

_{(Rf) b PF (6-} b) - as the anion represented by ^{_{the, (CF 3 CF 2) 2}} PF 4 -, (CF 3 CF 2) 3 PF 3 -, ((CF 3) 2 CF) 2 ^{_{PF 4 -, ((CF 3}} ) 2 CF) 3 PF 3 -, (CF 3 CF 2 CF 2) 2 PF 4 -, (CF 3 CF 2 CF 2) 3 PF 3 -, ((CF 3) 2 CFCF ^{_{2) 2 PF 4 -, (}} (CF 3) 2 CFCF 2) 3 PF 3 -, (CF 3 CF 2 CF 2 CF 2) 2 PF 4 - , and _{(CF 3 CF 2 CF 2 CF} 2) 3 PF 3 - Anions and the like represented by. Of ^{_{these, (CF 3 CF 2) 3}} PF 3 -, (CF 3 CF 2 CF 2) 3 PF 3 -, ((CF 3) 2 CF) 3 PF 3 -, ((CF 3) 2 CF) 2 ^{_{PF 4 -, ((CF 3}} ) 2 CFCF 2) 3 PF 3 - , and _{((CF 3) 2 CFCF 2} ) 2 PF 4 - anion represented by are preferred.

The anions represented by R ¹⁹ cBA _(4-c) ⁻ include (C ₆ F ₅ ) ₄ B ⁻ , ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ B ⁻ , (CF ₃ C ₆ H ₄ ). Examples thereof include anions represented by ₄ B ⁻ , (C ₆ F ₅ ) ₂ BF ₂ ⁻ , C ₆ F ₅ BF ₃ ⁻ and (C ₆ H ₃ F ₂ ) ₄ B ⁻ . Of these, anions represented by (C ₆ F ₅ ) ₄ B ⁻ and ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ B ⁻ are preferred.

The anions represented by R ¹⁹ _c GaA _(4-c) ⁻ include (C ₆ F ₅ ) ₄ Ga ⁻ , ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ Ga ⁻ , and (CF ₃ C ₆ H _4). ) ₄ Ga ⁻ , (C ₆ F ₅ ) ₂ Ga F ₂ ⁻ , C ₆ F ₅ Ga F ₃ ⁻ and (C ₆ H ₃ F ₂ ) ₄ Ga ⁻ , and the like. Of these, anions represented by (C ₆ F ₅ ) ₄ Ga ⁻ and ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ Ga ⁻ are preferred.

R ²⁰ SO ₃ ^- as the anion represented by, trifluoromethanesulfonic acid anion, pentafluoroethanesulfonate anion, heptafluoropropanesulfonate acid anion, nonafluorobutanesulfonic acid anion, pentafluorophenyl sulfonate anion, p- toluene Examples thereof include sulfonic acid anion, benzene sulfonic acid anion, camphor sulfonic acid anion, methane sulfonic acid anion, ethane sulfonic acid anion, propane sulfonic acid anion and butane sulfonic acid anion. Of these, trifluoromethanesulfonic acid anion, nonafluorobutanesulfonic acid anion, methanesulfonic acid anion, butanesulfonic acid anion, benzenesulfonic acid anion and p-toluenesulfonic acid anion are preferable.

The anions represented by (R ²⁰ SO ₂ ) ₃ C ⁻ are (CF ₃ SO ₂ ) ₃ C ⁻ , (C ₂ F ₅ SO ₂ ) ₃ C ⁻ , and (C ₃ F ₇ SO ₂ ) ₃ C ^−. and _{(C 4 F 9 SO 2)} 3 C - anion such as represented and the like.

The anions represented by (R ²⁰ SO ₂ ) ₂ N ⁻ are (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , and (C ₃ F ₇ SO ₂ ) ₂ N ^−. And (C ₄ F ₉ SO ₂ ) ₂ N ⁻ anions and the like can be mentioned. In addition, a cyclic imide in which the portions corresponding to the _two (R ²⁰ SO ₂ ) are bonded to each other to form a ring structure is also mentioned as an anion represented by (R ²⁰ SO ₂ ) ₂ N ⁻ .

The monovalent anion, in addition to the above anions, perhalogenated acid ion _{^(ClO 4} ^-, BrO 4 -, etc.), halogenated sulfonic acid ion _{^(FSO 3} ^-, ClSO 3 -, etc.), sulfate ion _(CH 3 SO _{4 ^{-, CF 3 SO 4 -,}} HSO 4 - , etc.), carbonate ions _{^{(HCO 3 -, CH 3 CO}} 3 - , etc.), aluminate ions (AlCl ₄ ^-, AlF ₄ ^-, etc.), hexafluoro bismuthate ions (BiF ₆ ^-), carboxylate ion _{^{(CH 3 COO -, CF 3}} COO -, C 6 H 5 COO -, CH 3 C 6 H 4 COO -, C 6 F 5 COO -, CF 3 C 6 H 4 COO - , etc. ), Arylborate ion (B (C ₆ H ₅ ) ₄ ⁻ , CH ₃ CH ₂ CH ₂ CH ₂ B (C ₆ H ₅ ) ₃ ^−, etc.), Thiosyanate ion (SCN ⁻ ) and Nitrate ion (NO ₃ ^−). ) Etc. can be used.

These anions may have a substituent, and as the substituent, an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, Arylsulfanyl group, alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, arylsulfonyl group, (meth) acryloyloxy group, hydroxy (poly) Examples thereof include an alkyleneoxy group, an amino group, a cyano group, a nitro group and a halogen atom.
Of these anions, sulfonic acid anions, carboxylic acid anions and the like are preferable.

The onium salt according to one aspect of the present invention may be an acid generator unit-containing resin in which an anion portion is bonded to a part of a polymer as one aspect of the photoacid generator (A). Examples of such an onium salt include resins having a unit in which X ⁻ in the above formulas (1) and (2) is represented by the following general formula (6). It is preferable that the onium salt is contained in the composition as one unit of the acid generator unit-containing resin, so that the diffusion of the acid generated during exposure can be suppressed and the LWR can be suppressed.
The unit represented by the general formula (6) may be contained in the resin (B) or may be contained in a resin different from the resin (B).

In the above formula (6), R ¹ and L ⁶ are independently selected from the same options as R ¹ and L ⁶ in the above formula (4a), respectively.
Z ¹ is a linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched alkenyl group having 1 to 12 carbon atoms, and a linear or branched aryl group having 6 to 14 carbon atoms. Further, some or all hydrogen atoms contained in these alkyl groups, alkenyl groups and aryl groups may be replaced with fluorine atoms. At least one methylene group in these groups may be substituted with a divalent heteroatom-containing group.

Examples of the anion portion represented by the above formula (6) include those shown below. However, the present invention is not limited to this.

The onium salt according to some aspects of the present invention preferably has a molar extinction coefficient at 365 nm of less than 1.0 × 10 ⁵ cm ² / mol, preferably less than 1.0 × 10 ⁴ cm ² / mol. Is more preferable.
Further, ketone derivatives acetal or the thioacetal onium salt was deprotected according to some aspects of the present invention preferably has a molar extinction coefficient of 365nm is 1.0 × ¹⁰ 5 ^cm 2 / mol or more, 1 More preferably, it is 0.0 × 10 ⁶ cm ² / mol or more.
The 365 nm molar extinction coefficient of the ketone derivative is preferably 5 times or more, more preferably 10 times or more, and 20 times or more the molar extinction coefficient of the onium salt according to some aspects of the present invention. The above is more preferable.
In order to obtain the above characteristics, an onium salt represented by the above formula (1) or (2) may be used.

<2> Method for synthesizing the above-mentioned onium salt Among the onium salts according to one aspect of the present invention, a method for synthesizing a sulfonium salt and an iodonium salt will be described. The present invention is not limited to this.

When the target sulfonium salt has an alkyl group in the sulfonio group portion (when R ¹¹ and R ¹² are alkyl groups in the above formula (1)), for example, the method shown below can be mentioned. First, an alkylsulfanil group-containing benzoyl chloride (h = 1 in the following formula (10a), and the aryl group may have R ¹³ groups) and a bromobenzene derivative having a specific R ¹⁴ group (the following formula). (I = 1 in (10b)) is reacted with a Grignard reagent to obtain an alkylsulfanil benzophenone derivative (10c).
The R ¹⁴ group forms a heterocyclic structure with a optionally substituted amino group or an aryl group to which the R ¹⁴ group is bonded. Such a bromobenzene derivative (10b) is readily available or can be synthesized at any time.
Then, after a sulfonium salt added an alkylating agent (R ^{12 2} _{SO 4),} such as dimethyl sulfate, subjected to salt exchange with a salt having a corresponding anion, dialkyl - obtain arylsulfonium salt (10d). Then, obtain the sulfonium salt (10e) of interest by acetalizing a carbonyl group with an acid catalyst and an alcohol (R ^{15 OH).}

When the target sulfonium salt has an aryl group in the sulfonio group portion (when R ¹¹ and R ¹² are aryl groups in the above formula (1)), for example, the method shown below can be mentioned. First, (a i = 1 is the following formula (11a).) Bromobenzene derivative having a specific ^{R 14} groups and a h = 1 in the arylsulfanyl group containing benzoyl chloride (formula (11b), an aryl group R ^It may have ¹³ groups) and Friedel-Crafts reaction with Lewis acid to obtain a bromobenzophenone derivative (11c).
R ¹⁴ group in formula (11a) is obtained by forming an aryl group and a heterocyclic structure bonded an amino group, or R ¹⁴ groups may be substituted. Such a bromobenzene derivative (11a) is readily available or can be synthesized at any time.
The carbonyl group is then acetalized with an acid catalyst and an alcohol (R ¹⁵ OH) to give the acetal form (11d). Then, a sulfonium salt is obtained by reacting with a sulfoxide compound (11e) having R ¹¹ groups and R ¹² groups using a Grignard reagent, and then salt exchange is carried out with a salt having a corresponding anion to obtain a target sulfonium salt ( 11f) is obtained.

In the case of iodonium salt, for example, the method shown below can be mentioned. First, a specific R ¹⁴ group-containing benzene (m = 1 in the following formula (12a)) and iodobenzoyl chloride (n = 1 in the following formula (12b), and the aryl group may have R ¹³ groups). Is reacted with Friedel-Crafts using Lewis acid to obtain an iodobenzophenone derivative (12c).
R ¹⁴ group in formula (12a) is obtained by forming an aryl group and a heterocyclic structure bonded an amino group, or R ¹⁴ groups may be substituted. Such a bromobenzene derivative (12a) is readily available or can be synthesized at any time.
Then, the iodonium salt (12e) by reaction with an aromatic compound R ^{17 H (12d)} after the reaction with an oxidizing agent such as metachloroperbenzoic acid (mCPBA) in the presence of an acid such as trifluoromethanesulfonic acid, then, acid catalyst and alcohol after obtaining acetal body (12f) by acetalizing a carbonyl group with (R ^{15 OH),} object iodonium salt by salt exchange with a salt having a corresponding anion as needed (12 g) is obtained.

When the anion portion of the onium salt is a polymer component bonded to a part of the polymer, for example, the synthesis method shown below can be mentioned. First, an onium salt having a polymerizable functional group in the anion portion is obtained by exchanging a salt of the above-mentioned sulfonium salt ((10e) or (11f) or iodonium salt (12 g) with a commercially available or optionally synthesized sulfonate having a polymerizable functional group. Polymerizable onium salt) is then obtained by copolymerizing the obtained polymerizable onium salt with an acid dissociable compound or the like using a radical initiator to obtain a desired polymer component.

If an onium salt of interest is L ^4, or which L ⁵ have the alkenylene group, for example, synthetic methods shown below. An unsaturated ketone compound (d) is obtained by subjecting an acetyl compound (b) having ¹³ or R ¹⁴ groups and an aldehyde compound (c) to an aldol reaction with sodium hydroxide.
R ¹⁴ group in formula (b) are those which form an aryl group and a heterocyclic structure bonded an amino group, or R ¹⁴ groups may be substituted. Such acetyl compound (b) is readily available or can be synthesized at any time.
Next, the unsaturated ketone compound and a sulfoxide compound having R ¹¹ groups and R ¹² groups are reacted with a strong acid such as methanesulfonic acid using a dehydrating agent to obtain a sulfonium salt. Then, it is possible to obtain the sulfonium salt of interest by acetalizing a carbonyl group with an acid catalyst and an alcohol (R ^{15 OH).}

<3> Composition One aspect of the present invention relates to a composition containing the photoacid generator (A) and an acid-reactive compound. Preferably, the composition further comprises an acid diffusion inhibitor.

(Photoacid generator)
The content of the photoacid generator in the composition of one aspect of the present invention is preferably 0.1 to 50 parts by mass with respect to 100 parts by mass of the resist composition component excluding the photoacid generator. It is more preferably 1 to 30 parts by mass, and even more preferably 3 to 15 parts by mass.

In calculating the content of the photoacid generator, the organic solvent is not contained in 100 parts by mass of the resist composition component.

When the photoacid generator is contained in the resin as one unit, that is, when the photoacid generator is a polymer component, it is based on the mass excluding the polymer main chain. Further, the photoacid generator is a polymer component, and the units represented by the general formulas (5a) to (5b) described later (hereinafter, also referred to as "unit C") and the general formulas (4a) to (4a) to be described later. A unit that acts as the photoacid generator when it is included as a unit of the same polymer together with at least one unit selected from the group consisting of the unit represented by (4d) (hereinafter, also referred to as "unit B") (hereinafter, also referred to as "unit B"). , "Unit A") is preferably 0.1 to 40 mol%, more preferably 1 to 30 mol%, and further preferably 3 to 20 mol% of the total unit of the polymer. preferable.
In the resist composition, the photoacid generator may be used alone or in combination of two or more, regardless of the polymer component and the low molecular weight component, or may be used in combination with other photoacid generators.

Examples of the photoacid generator other than the photoacid generator containing the onium salt include general-purpose ionic photoacid generators and nonionic photoacid generators. Examples of the ionic photoacid generator include onium salt compounds such as iodonium salt and sulfonium salt other than the above. Examples of the nonionic photoacid generator include N-sulfonyloxyimide compounds, oxime sulfonate compounds, organic halogen compounds, sulfonyldiazomethane compounds and the like.
When a photoacid generator other than the photoacid generator containing the onium salt is contained, the content thereof shall be 0.1 to 50 parts by mass with respect to 100 parts by mass of the resist composition component excluding the total amount of the photoacid generator. Is preferable.

(Acid-reactive compound)
The acid-reactive compound is at least one selected from the group consisting of a compound having a protecting group that is deprotected by an acid, a compound having a polymerizable group that is polymerized by an acid, and a cross-linking agent having a cross-linking action by an acid. It is preferable to have.
A compound having a protecting group that is deprotected by an acid is a compound that produces a polar group by deprotecting the protecting group by an acid and changes its solubility in a developing solution. For example, in the case of water-based development using an alkaline developer or the like, it is insoluble in an alkaline developer, but the protective group is deprotected from the compound in the exposed portion by the acid generated from the photoacid generator by exposure. , A compound that is soluble in alkaline developers.

In one aspect of the present invention, it is particularly preferable that the acid-reactive compound is a resin (B) whose solubility in a developing solution changes due to the action of an acid.
(Resin (B))
The resin (B) has at least one of the units B represented by the above (4a) to (4d) having a protecting group that is deprotected by an acid.
The unit B is a unit contained in the resin (B) that has a protecting group that is deprotected by an acid, and a polar group is generated by deprotecting the protecting group by an acid, and the solubility in a developing solution changes. Is. For example, in the case of water-based development using an alkaline developer or the like, the protective group is deprotected from the unit B in the exposed portion by the acid generated from the photoacid generator by exposure, although it is insoluble in the alkaline developer. This is a compound that becomes soluble in an alkaline developer.

In the present invention, the developer is not limited to the alkaline developer, and may be an aqueous neutral developer or an organic solvent developer. Therefore, when an organic solvent developing solution is used, a compound having a protecting group that is deprotected by an acid is polar because the protecting group is deprotected from the compound in an exposed portion by an acid generated from the photoacid generator by exposure. It is a compound that produces a group and has reduced solubility in an organic solvent developing solution.

Examples of the polar group include a hydroxy group, a carboxy group, an amino group and a sulfo group. Among these, a polar group having −OH in the structure is preferable, and a hydroxy group or a carboxy group is preferable.
Specific examples of the protecting group to be deprotected with an acid include a group forming a carboxy group and a tertiary alkyl ester group; an alkoxyacetal group; a tetrahydropyranyl group; a syroxy group and a benzyloxy group. As the compound having the protecting group, a compound having a styrene skeleton, a methacrylate or an acrylate skeleton in which these protecting groups are pendant, and the like are preferably used.

The resin (B) may be a low molecular weight compound containing a protecting group instead of the polymer component having a unit B having a protecting group that is deprotected by an acid.

The protecting group-containing low molecular weight compound has at least one of the units represented by the above (4a) to (4d), similarly to the above resin (B).

In the above formulas (4a) to (4d), R ¹ is any one selected from the group consisting of a hydrogen atom, an alkyl group and an alkyl halide group.
Examples of the alkyl group include methyl, ethyl, n-propyl, n-butyl, isopropyl, t-butyl, cyclopropyl group, cyclobutyl group, cyclopentyl group and cyclohexyl group, and some of these hydrogen atoms are halogen. It may be replaced with. Among them, a hydrogen atom, a methyl group, and a trifluoromethyl group are particularly preferable.

In the above general formulas (4a) to (4d), the site represented by the following formula (a-1) or (a-2) is a protecting group that deprotects with an acid (hereinafter, also referred to as "acid instability group"). Yes, it decomposes by the action of acid to generate carboxylic acid or phenolic hydroxyl group, and its solubility in the developing solution changes.
The broken lines in the following formulas (a-1) and (a-2) indicate the bonding portion with L ¹ or the oxygen atom in the above formulas (4a) to (4d). Formula (a-1) and (a-2) in ^R 2 to R ⁷ may be selected from the same options as ^R 2 to R ⁷ in the general formula (4a) ~ (4d) are preferred.

In the above formula (a-1), R ² and R ³ are independently linear, branched or cyclic alkyl groups, for example, methyl, ethyl, n-propyl, n-butyl, isopropyl and t-butyl. , Cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, adamantan-1-yl group, adamantan-2-yl group, norbornan-1-yl group, alkyl group such as norbornan-2-yl group and the like.

R ⁴ is a linear, branched, or cyclic alkyl group that may have a substituent, and the alkyl group is selected from the same options as each of the alkyl groups of R ² , and some of these hydrogen atoms are It may be substituted with a hydroxyl group, an alkoxy group, an oxo group, an amino group, an alkylamino group or the like. The R ⁵ , R ⁶ and R ⁷ may form a ring structure in a single bond either directly or via a selection from the group consisting of methylene groups.

In the above formula (a-2), R ⁵ and R ⁶ are each independently a hydrogen atom and a linear or cyclic alkyl group, and the alkyl group is the same option as the alkyl group of R ^2. Is selected from.

R ⁷ is a linear, branched or cyclic alkyl group which may have a substituent, the alkyl group is selected from the same options as each of the alkyl groups of R ² , and some of these hydrogen atoms are hydroxyl groups. , Alkyl group, oxo group, amino group, alkylamino group and the like may be substituted. Wherein R ^5, R ⁶ and R ⁷ may form a ring structure through any one selected from the group consisting of directly or methylene group with a single bond.

Specifically, the structures shown below can be exemplified as the above formulas (a-1) and (a-2). However, the present invention is not limited to this.

R ⁸ in the above general formulas (4c) to (4d) is an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an alkylsulfanyl group, an alkylsulfinyl group, an alkylsulfonyl group, an amino group, a cyano group, a nitro group and a halogen. It is one selected from the group consisting of atoms. These are selected from the same options as each of R ¹³ .

L ⁶ in the above general formulas (4a) to (4d) is a linear, branched or cyclic alkylene carbonyloxy group or alkylene carbonylamino group which may have a direct bond, a carbonyloxy group, a carbonylamino group and a substituent. The carbonyloxy group or carbonylamino group binds to the acid instability group.
In the above equations (4a) to (4d), l is an integer of 1 to 2, m is an integer of 0 to 4 when l is 1, and n is an integer of 0 to 6 when l is 2. When is 1, it is an integer of 1 to 5, when l is 2, it is an integer of 1 to 7, and m + n is 1 to 5 when l is 1, and 1 to 7 when l is 2.

Specific examples of the unit B represented by the general formulas (4a) to (4d) shown below can be exemplified. However, the present invention is not limited to this.

In place of or in addition to the resin (B), the composition may contain a compound having a polymerizable group that polymerizes with an acid and / or a cross-linking agent having a cross-linking action with an acid. A compound having a polymerizable group that polymerizes with an acid is a compound that changes its solubility in a developing solution by polymerizing with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and after polymerization, the compound is reduced in solubility in an aqueous developer. Specific examples thereof include compounds having an epoxy group, a vinyloxy group, an oxetanyl group and the like.

The compound having a polymerizable group polymerized by an acid may be a polymerizable low molecular weight compound or a unit-containing polymer component having a polymerizable group.
A cross-linking agent having a cross-linking action with an acid is a compound that changes its solubility in a developing solution by cross-linking with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and reduces the solubility of the compound in an aqueous developer after polymerization or cross-linking. Specific examples thereof include a cross-linking agent having a cross-linking group such as an epoxy group, a vinyloxy group, a 1-alkoxyamino group and an oxetanyl group. When the compound is a cross-linking agent having a cross-linking action, examples of the compound to be cross-linked, that is, a compound whose solubility in a developing solution changes by reacting with the cross-linking agent, includes a compound having a phenolic hydroxyl group.

The compound having a cross-linking action by an acid may be a cross-linking low molecular weight compound or a unit-containing polymer component having a cross-linking group.
In addition to at least one of the units B represented by the above formulas (4a) to (4d), the resin (B) may contain other units usually used in the resist composition in the polymer component. Good. Other units include, for example, a unit having at least one skeleton selected from the group consisting of a lactone skeleton, a sultone skeleton, a sulfolane skeleton, a lactam skeleton, and the like; an ether structure, an ester structure, an acetal structure, and a hydroxy group. A unit having at least one structure selected from the group consisting of structures and the like; a hydroxyaryl group-containing unit; and the like can be mentioned. Further, the resin (B) may contain the above unit A.

The resin (B) is a homopolymer containing the unit B, or at least one unit C selected from the group consisting of the unit B, the unit A, and the general formulas (5a) to (5b) described later. And, as a copolymer having, may be included in the composition. When the resin (B) is a copolymer, the unit B in the resin (B) is preferably 3 to 50 mol%, more preferably 5 to 35 mol%, 7 of all polymer units. It is more preferably ~ 30 mol%.

(Resin (C))
In one aspect of the present invention, the composition comprises a resin (C) containing one or more units C represented by the following formulas (5a) to (5b), or the resin (B) is the above. It is preferred that it further comprises at least one of the units C.

In the above formulas (5a) and (5b), R ¹ , R ⁸ and L ⁶ are independently selected from the same options as those of R ¹ , R ⁸ and L ^{6 in} the above formulas (4a) to (4d), respectively. Will be done.
R ⁹ is a cyclic group containing at least one selected from the group consisting of -C (O) -O-, -SO _2- and -O-SO _2- .
p is an integer from 0 to 4, and q is an integer from 1 to 5.
Examples of the cyclic group include a lactone skeleton, a sultone skeleton, and a group containing a sulfolane skeleton.

The unit C represented by the above formulas (5a) to (5b) is contained in the copolymer containing the above unit A and / or at least one of the above formulas (4a) to (4d) as the unit B. It may be a unit of another polymer.
The unit represented by the above formula (5a) is a hydroxyaryl group-containing unit (hereinafter, also referred to as “unit C1”), and the unit represented by the above formula (5b) is a lactone skeleton; a sultone skeleton; a sulfolane skeleton-containing unit. (Hereinafter, also referred to as "unit C2").

When a polymer having a hydroxyaryl group-containing unit C1 is used, it can be a hydrogen source when the photoacid generator is decomposed, the acid generation efficiency can be further improved, and the sensitivity becomes high, which is preferable. Further, since the polymer having the hydroxyaryl group-containing unit C1 has a low ionization potential, when an electron beam or extreme ultraviolet (EUV) is used for the first active energy ray described later, secondary electrons are easily generated, and the above-mentioned photoacid generation It is preferable because it improves the acid generation efficiency of the agent and increases the sensitivity.

Examples of the hydroxyaryl group-containing unit C1 shown below can be exemplified. However, the present invention is not limited to this.

When the hydroxyaryl group-containing unit C1 is included as a unit of the same polymer together with at least one selected from the group consisting of the unit A and the unit B, the hydroxyaryl group-containing unit C1 is a positive type for aqueous development. For the resist composition, it is preferably 3 to 90 mol%, more preferably 5 to 80 mol%, and even more preferably 7 to 70 mol% of the total unit of the polymer. For water-based developed negative resist compositions, it is preferably 60 to 99 mol%, more preferably 70 to 98 mol%, and even more preferably 75 to 98 mol% of the total polymer units.

The lactone skeleton; sultone skeleton; sulfolane skeleton-containing unit C2 can be exemplified as shown below. However, the present invention is not limited to this.

When a sulton skeleton-containing unit or a sulforane skeleton-containing unit is used as the unit C2, an acid is generated by ionization by electron beam or extreme ultraviolet (EUV) irradiation as the first active energy ray, and thus some aspects of the present invention. It is possible to produce more ketone derivatives having absorption in the second active energy ray by contributing to the deprotection reaction of the acetal of the onium salt in. Further, it is preferable because the solubility of the resin in the developing solution is further changed by contributing to the polarity conversion by the reaction with the resin (B) containing the unit B, so that the sensitivity becomes high.

The unit C2 is a lactone skeleton-containing unit, a sulton skeleton-containing unit; when the sulfolane skeleton-containing unit is included as a unit of the same polymer together with at least one selected from the group consisting of the unit A and the unit B, the unit C2 is used. It is preferably 3 to 70 mol%, more preferably 5 to 50 mol%, and even more preferably 7 to 40 mol% of the total unit of the polymer.

In the composition of one aspect of the present invention, in addition to the unit A, the unit B, and the unit C, other compounds are contained in the resin (B) and / or the resin (C) as units of the same polymer. May be good. The other compounds are not particularly limited as long as they are compounds generally used as resin compositions such as ArF lithography, KrF lithography, electron beam lithography, and EUV lithography.

(Low molecular weight compound containing sulfone or sulfonic acid ester, or polymer)
The composition of one embodiment of the present invention may contain a low molecular weight compound containing a sulfone or a sulfonic acid ester, or a polymer.

The sulfone or sulfonic acid ester is not particularly limited, but one having a linear, branched or cyclic alkyl or aryl group is preferable. It is more preferable that some or all hydrogen atoms of the alkyl or aryl group are replaced with fluorine atoms. Since the compound is contained and ionized by irradiation with an electron beam or extreme ultraviolet rays to generate an acid, the sensitivity of the resist can be increased.
The content of the compound containing sulfone or sulfonic acid ester is preferably 0.1 to 50 parts by mass with respect to 100 parts by mass of the resist composition component excluding the total amount of the photoacid generator.

Specific examples of the compound containing the above-mentioned sulfone or sulfonic acid ester include dimethyl sulfone, isopropylmethyl sulfone, methylphenyl sulfone, diphenyl sulfone, phenyltrifluoromethyl sulfone, bis (4-fluorophenyl) sulfone, and bis (phenylsulfonyl) methane. Methyl methanesulfonate, isopropyl methanesulfonate, ethyl trifluoromethanesulfonate, methyl benzenesulfonate, 1,3-propanesulfone, 1-propen 1,3-sulfone, 1,4-butanesulfone, 1,2-bis (tosyloxy) ) Etan, 1,8-naphthosulfone, etc., which may be used alone or in combination of two or more.

(Fluorine-containing water-repellent polymer)
The composition of one embodiment of the present invention may contain a fluorine-containing water-repellent polymer.

The fluorine-containing water-repellent polymer is not particularly limited, and examples thereof are those usually used in an immersion exposure process, and a polymer having a higher fluorine atom content than the polymer is preferable. When a resist film is formed using a composition containing a fluorine-containing water-repellent polymer, the fluorine-containing water-repellent polymer is unevenly distributed on the surface of the resist film due to the water repellency of the fluorine-containing water-repellent polymer. Can be transformed into.
As for the fluorine content of the fluorine-repellent polymer, it is preferable that 25 mol% or more of hydrogen atoms in the hydrocarbon group in the fluorine-repellent polymer is fluorinated, and 50 mol% or more is fluorinated. Is more preferable.

The content of the fluorine-repellent polymer in the composition is 0.5 to 10 parts by mass with respect to 100 parts by mass of the above-mentioned polymer (non-fluorine-repellent polymer) of one embodiment of the present invention. However, it is preferable from the viewpoint of improving the hydrophobicity of the resist film. The fluorine-repellent polymer may be used alone or in combination of two or more.

(Photosensitizer and its precursor)
The composition of one embodiment of the present invention may contain a photosensitizer and a precursor thereof. Hereinafter, the photosensitizer and its precursor are collectively referred to as a "sensitizing compound".
The sensitizing compound is not particularly limited as long as the effect of the onium salt according to some aspects of the present invention is not reduced, but the thioxanthone derivative and its acetalized compound, the benzophenone derivative and its acetalized compound, the naphthalene derivative, and the like. Examples thereof include anthracene derivatives, alkyl alcohols and aryl alcohols.
Further, as the sensitizing compound, for example, a photosensitizer precursor represented by the following general formula (7) may be contained. By containing the photosensitizer precursor, a photosensitizer is generated from the photosensitizer precursor by irradiating with the first active energy ray, and then by irradiating with the second active energy. Since the sensitizing reaction generated between the photosensitizer and the onium salt according to some aspects of the present invention can be utilized, it is preferable because the sensitivity of the resist can be increased.

In the above formula (7), Ar ¹¹ and Ar ¹² are phenylene groups which may independently have a substituent, and R ²¹ is an alkylsulfanyl group which may have a substituent. , Whichever is selected from the group consisting of an arylsulfanyl group and an alkylsulfanylphenyl group, W is any one selected from the group consisting of a sulfur atom, an oxygen atom and a direct bond, and R ²² is a substituent. Is either an alkyl group or an aryl group which may have, Y is an independent each of an oxygen atom and an sulfur atom, and R ²³ and R ²⁴ are independently of each. , Whichever is selected from the group consisting of linear, branched or cyclic alkyl groups, alkenyl and alkynyl groups and aralkyl groups which may have substituents, wherein R ²³ and R ²⁴ are They may be combined with each other to form a ring structure with two Ys in the formula.

Ar ¹¹ and Ar ¹² in the above formula (7) are phenylene groups, respectively, and the substituents other than R ²¹ or −WR ²² (hereinafter, the substituents of Ar ¹¹ and Ar ¹² are “fourth substitutions”. It may have a group). It is preferable that Ar ¹¹ and Ar ¹² are not indirectly bonded to form a ring from the viewpoint of synthesis.
Examples of the fourth substituent include an electron donating group. Specific examples of the electron donating group include an alkyl group, an alkenyl group, an alkoxy group, an alkoxyphenyl group, an alkylsulfanyl group, an arylsulfanyl group and an alkylsulfanylphenyl group. A fourth substituent, a polyethylene glycol chain _{(- (CO 2 H 4)} n -) may be mentioned long-chain alkoxy group having. Further, when the 4th substituent is bonded to the para position of Ar ¹¹ or Ar ¹² , it may have an OH group as the 4th substituent.

In the present invention, the substitution position such as "para position" of Ar ¹¹ or Ar ¹² is the position with respect to the group to which the quaternary carbons that bond the two Y, Ar ¹¹ and Ar ^{12 in} the above formula (7) are bonded. To say. For not only the fourth substituent but also other groups, the reference of the substitution position such as "para position" is the position with respect to the group bonded to the quaternary carbon.
The alkyl group as the fourth substituent, the alkenyl group, the alkyl group of R ¹¹ in the formula (1), is selected from the same options as the alkenyl group. The alkoxy group as the fourth substituent is selected from the same options as the alkoxy group (−OR) in the first substituent.
Alkylsulfanyl group as the fourth substituent. As the arylsulfanyl group and alkylsulfanyl phenyl group, an alkylsulfanyl group R ²¹ described below are the same as those of the arylsulfanyl groups and alkylsulfanyl phenyl group.

Any methylene group of the above alkyl group in the fourth substituent may be a group substituted with a -C (= O) -group or an -OC (= O) -group. However, it is preferable that the -C (= O) -group and the -OC (= O) -group do not directly bond to Ar ¹¹ and Ar ¹² in the above four substituents. Further, it is preferable that the fourth substituent does not have a continuous connection of heteroatoms such as —O, —S—S— and —SO—.
When the fourth substituent is an alkoxy group, an alkoxyphenyl group, an alkylsulfanyl group, an arylsulfanyl group and an alkylsulfanylphenyl group, it is bonded to the ortho-position and / or para-position of the phenylene group which is Ar ¹¹ and Ar ^12. It is preferable to have. At that time, the number of substituents is preferably 3 or less.

The R ²¹ in the above formula (7) is any one selected from the group consisting of an alkylsulfanil group which may have a substituent, an arylsulfanil group and an alkylsulfanilphenyl group.
Specific examples alkylsulfanyl group R ^21, methylsulfanyl group, ethylsulfanyl group, n- propyl sulfanyl group, an alkylsulfanyl group having 1 to 20 carbon atoms, such as n- butyl sulfanyl group preferably having a carbon number 1 to 12 Alkyl sulfanyl group is more preferable.
Specific examples of the arylsulfanil group of R ²¹ include a phenylsulfanil group and a naphthylsulfanil group.

Specifically, as the alkyl sulfanyl phenyl group of R ^21, a phenyl group to which an alkyl sulfanyl group having 1 to 20 carbon atoms such as methyl sulfanyl phenyl group, ethyl sulfanyl phenyl group, propyl sulfanyl phenyl group and butyl sulfanyl phenyl is bonded is preferably mentioned. A phenyl group to which an alkylsulfanyl group having 1 to 12 carbon atoms is bonded is more preferable. The substitution position of the alkylsulfanil group bonded to the phenylene group in R ²¹ is not particularly limited, but the para position is preferable from the viewpoint of enhancing the electron donating property and the molar extinction coefficient of 365 nm. It is preferable that R ²¹ is bonded to the ortho-position or para-position of the phenylene group which is Ar ¹¹ .

The R ²² in the above formula (7) is either an alkyl group or an aryl group which may have a substituent, and is selected from the same options as in each of the above R ¹¹ .

R ²¹ and R ²² in the above formula (7) may have a substituent, and as the substituent (hereinafter, the substituent of R ²¹ and R ²² is referred to as a “fifth substituent”), in particular. Although not limited, examples thereof include an electron-withdrawing group in addition to the above-mentioned fourth substituent. Examples of the electron-withdrawing group include a nitro group and a sulfonyl group. A polymerizable group may be introduced into R ²¹ or R ²² and the polymer may be used as a polymer having a sensitizing effect, or the fifth substituent may contain a polymer main chain. Examples of the polymerizable group include a (meth) acryloyloxy group, an epoxy group, a vinyl group and the like.

When W in the above formula (7) is an oxygen atom or a sulfur atom, it is preferable that the W is the ortho-position or the para-position of Ar ¹² . When the W is a direct bond, it is preferable that the W is in the ortho or para position of Ar ¹² .

The total number of carbon atoms of R ^{21 in} the above formula (7) is not particularly limited, and when R ²¹ has a substituent, the total number of carbon atoms is preferably 1 to 20. The total number of carbon atoms of R ^{22 in} the above formula (7) is not particularly limited, and when R ²² has a substituent, the total number of carbon atoms is preferably 1 to 20.
When the photosensitizer precursor is a polymer, the total carbon number of R ²¹ and R ²² excluding the portion containing the polymer main chain serving as the fifth substituent is preferably 1 to 20.

Y is independently either an oxygen atom or a sulfur atom, respectively.
R ²³ and R ²⁴ are selected from the group consisting of linear, branched or cyclic alkyl groups, alkenyl and alkynyl groups, and aralkyl groups, each of which may independently have a substituent. It is either. The alkyl group and alkenyl group of R ²³ and R ²⁴ are selected from the same options as the alkyl group and alkenyl group of R ¹¹ in the above formula (1).
The alkynyl groups R ²³ and ^{R 24} are selected from those portions of the above-described alkyl group ^{R 23} and ^{R 24} becomes a triple bond. The aralkyl group of R ²³ and R ⁴ is selected from those in which a part of hydrogen of the alkyl group of R ²³ and R ²⁴ is substituted with an aryl group such as a phenyl group or a naphthyl group.

R ²³ and R ²⁴ in the above formula (7) may have a substituent, and as the substituent (hereinafter, the substituent of R ²³ and R ²⁴ is referred to as a “sixth substituent”), in particular. Although not limited, in addition to the above-mentioned fifth substituent, an aryl group such as a phenyl group and a naphthyl group can also be mentioned.
The total number of carbon atoms of R ²³ and R ^{24 in} the above formula (7) is not particularly limited, and the photosensitizer precursor may be a constituent component of the polymer, but R ²³ or R ²⁴ is a substituent. When having, it is preferable that the total number of carbon atoms is 1 to 20, respectively.

The R ²³ and R ²⁴ may be coupled to each other to form a ring structure with two Ys in the formula.
That is, the photosensitizer precursor according to one aspect of the present invention is represented by the following formula (8). In the following equation (8), −R ²⁵ −R ²⁶ − is preferably − (CH ₂ ) _n −, and n is an integer of 2 or more. There is no particular limitation as long as n is 2 or more, but it is preferably 8 or less from the viewpoint of ease of synthesis. R ²⁵ and R ²⁶ correspond to those in which R ²³ and R ²⁴ in the above formula (7) are bonded to each other to form a ring.

In the above formula (8), R ²⁵ and R ²⁶ may have the same sixth substituent as the above R ²³ and R ²⁴ . A polymerizable group may be introduced into R ²³ or R ^24, and the polymer obtained by introducing the polymerizable group may be used as a polymer having a sensitizing effect.
The total number of carbon atoms of R ²³ and R ²⁴ is preferably 1 to 20. When the photosensitizer precursor is a polymer, the total carbon number of R ²³ and R ²⁴ excluding the portion containing the polymer main chain serving as the sixth substituent is preferably 1 to 20.

The photosensitizer precursor after acid treatment of the photosensitizer precursor, that is, the photosensitizer having a carbonyl group generated when the photosensitizer precursor is deprotected by an acid has a molar extinction coefficient of 1 at 365 nm. It is preferably 0.0 × 10 ⁵ cm ² / mol or more. The molar extinction coefficient at 365 nm is preferably high, but 1.0 × 10 ¹⁰ cm ² / mol or less is a realistic value. To set the molar extinction coefficient in the above range, for example, one or more alkylsulfanyl groups, arylsulfanyl groups, alkylsulfanylphenyl groups, or two or more alkoxy groups or aryloxy groups are used in the photosensitizer precursor. It is possible to include the configuration.
In the present invention, the molar extinction coefficient is at 365 nm measured by a UV-VIS absorptiometer using chloroform as a solvent.
The photosensitizer precursor according to one aspect of the present invention has -Y-R ²³ and -Y-R ^{24 in the} whole photosensitizer precursor from the viewpoint of ease of synthesis and absorption characteristics. , Or, 4 or less groups selected from the group consisting of an alkylsulfanyl group, an arylsulfanyl group, an alkoxyphenyl group, an alkylsulfanylphenyl group, an alkoxy group and an aryloxy group other than -Y-R ^25- R ^26- Y-. Is preferable.

Examples of the photosensitizer precursor represented by the above formula (7) or (8) include the following photosensitizer precursors. In the examples below, those shown in parentheses represent polymer units. Photosensitizer precursors in some aspects of the invention are not limited to this.

A method for synthesizing a photosensitizer precursor according to one aspect of the present invention will be described. The present invention is not limited to this.
When the photosensitizer precursor according to one aspect of the present invention has a structure represented by the following formula (9), it can be synthesized by, for example, the following method. First, one selected from the group consisting of alkoxybenzoyl chloride having ²² -WR groups, alkylbenzoyl chloride, thioalkoxybenzoyl chloride and thioalkylbenzoyl chloride, and those in which these alkyl groups are aryl groups. , R ²¹ groups of benzene halides are used to react with a Grignard reaction to obtain a benzophenone derivative. Next, the benzophenone derivative is reacted with an alcohol and, if necessary, an orthoester such as trialkyl orthoester (R ²³ , R ²⁴ = alkyl group) as a dehydrating agent at 0 ° C. to a reflux temperature for 1 to 120 hours. Therefore, the derivative represented by the following formula (9) can be obtained.

(Other ingredients)
In the composition of one aspect of the present invention, an acid diffusion control agent, a surfactant, an organic carboxylic acid, an organic solvent, and a dissolution inhibitor used in ordinary resist compositions are further added as optional components in addition to the above components. , Stabilizers and dyes, polymers other than the above, etc. may be included in combination.

The acid diffusion control agent has the effect of controlling the diffusion phenomenon of the acid generated from the photoacid generator in the resist film and controlling an unfavorable chemical reaction in the non-exposed region. Therefore, the storage stability of the obtained resist composition is further improved, the resolution of the resist is further improved, and the line width change of the resist pattern due to the fluctuation of the leaving time from the exposure to the development process can be suppressed. , A resist composition having excellent process stability can be obtained.

Examples of the acid diffusion control agent include a compound having one nitrogen atom in the same molecule, a compound having two nitrogen atoms, a compound having three nitrogen atoms, an amide group-containing compound, a urea compound, and a nitrogen-containing heterocyclic compound. Be done. Further, as the acid diffusion control agent, a photodisintegrating base that is exposed to exposure to generate a weak acid can also be used. Examples of the photodisintegrating base include onium salt compounds and iodonium salt compounds that are decomposed by exposure and lose their acid diffusion controllability.

Specifically, as the acid diffusion control agent, Japanese Patent Application Laid-Open No. 3577743, Japanese Patent Application Laid-Open No. 2001-215689, Japanese Patent Application Laid-Open No. 2001-166476, Japanese Patent Application Laid-Open No. 2008-102383, Japanese Patent Application Laid-Open No. 2010-243773, JP-A-2011-37835 and Examples thereof include the compounds described in Open 2012-173505.

The content of the acid diffusion control agent is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, and 0.05 to 0.05 parts by mass with respect to 100 parts by mass of the resist composition component. It is more preferably 3 parts by mass.
The above-mentioned 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 polymers, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters. Examples thereof include agents, fluorosurfactants, and organosiloxane polymers.
The content of the surfactant is preferably 0.0001 to 2 parts by mass, more preferably 0.0005 to 1% by mass, based on 100 parts by mass of the resist composition component.

Examples of the organic carboxylic acid include aliphatic carboxylic acid, alicyclic carboxylic acid, unsaturated aliphatic carboxylic acid, oxycarboxylic acid, alkoxycarboxylic acid, ketocarboxylic acid, benzoic acid derivative, phthalic acid, terephthalic acid, isophthalic acid, 2 Examples thereof include −naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid and the like. When electron beam exposure is performed by vacuuming, it may volatilize from the surface of the resist film and contaminate 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 preferable.
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 even more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the resist composition component. Is.

Examples of the organic solvent include ethylene glycol monoethyl ether acetate, cyclohexanone, 2-heptanone, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether propionate, and propylene glycol monoethyl ether. Acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl β-methoxyisobutyrate, ethyl butyrate, propyl butyrate, methylisobutylketone, ethyl acetate, isoamyl acetate, ethyl lactate, toluene, xylene, cyclohexyl acetate, diacetone Alcohol, N-methylpyrrolidone, N, N-dimethylformamide, γ-butyrolactone, N, N-dimethylacetamide, propylene carbonate, ethylene carbonate and the like are preferable. These organic solvents are used alone or in combination.

The resist composition component is preferably dissolved in the above-mentioned container solvent and dissolved in a solid content concentration of 1 to 40% by mass. It is more preferably 1 to 30% by mass, still more preferably 3 to 20% by mass. The above film thickness can be achieved by setting the solid content concentration in the range.

When the resist composition of one aspect of the present invention comprises a polymer, the polymer preferably has a weight average molecular weight of 2000-20000, more preferably 2000-50000, and further 2000-15000. preferable. The preferred dispersity (molecular weight distribution) (Mw / Mn) of the polymer is 1.0 to 1.7, more preferably 1.0 to 1.2, from the viewpoint of sensitivity. The weight average molecular weight and dispersity of the polymer are defined as polystyrene-equivalent values measured by GPC.

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

<4> Device Manufacturing Method One embodiment of the present invention includes a step of forming a resist film by applying the above composition onto a substrate, and a step of irradiating the resist film with first active energy rays. A method for manufacturing a device including a step of irradiating a resist film after irradiation with the first active energy ray with a second active energy ray and a step of developing the resist film after irradiation with the second active energy ray to obtain a pattern. Is.

One embodiment of the present invention includes a step of forming a resist film, a step of irradiating a first active energy ray, a step of irradiating a second active energy, and a step of forming a pattern using the above composition. It may be a method of manufacturing a substrate having a pattern before obtaining an individualized chip.
One embodiment of the present invention includes a step of forming a coating film on a substrate using the above composition, and exposing the coating film using the first active energy ray and the second active energy ray to obtain an interlayer insulating film. It may be a method of manufacturing a device including a step of obtaining the above.

The first active energy ray and the second active energy ray are not particularly limited as long as the onium salt according to some aspects of the present invention does not have significant absorption in the second active energy ray, but the first active energy ray is limited. It is preferable that the wavelength of the line is shorter than that of the second active energy line, or the energy of the photon or particle line is high. Each active energy ray is illustrated below, but the wavelength of the first active energy ray is shorter than that of the second active energy ray, or the energy of the photon or particle beam is high.
The first active energy ray is not particularly limited as long as an active species such as an acid can be generated in the resist film after irradiation with the resist film. For example, KrF excimer laser light, ArF excimer laser light, electron beam or extreme. Ultraviolet light (EUV) and the like are preferably mentioned.

The second active energy ray is a ketone produced by deprotecting the acetal or thioacetal moiety of the onium salt according to some aspects of the present invention by an acid generated in the resist film after irradiation with the first active energy ray. Any light may be used as long as it can activate the derivative to generate an active species such as an acid. For example, it means KrF excimer laser light, UV, visible light, etc., and it is particularly preferable to use light in the range of 365 nm (i line) to 436 nm (g line) among UV light.

The method for manufacturing a device according to one embodiment of the present invention may include a step of heating with a heating wire or a laser between a step of irradiating the first active energy and a step of irradiating the second active energy ray. preferable. By having this step, the decomposition efficiency of the onium salt is improved, which may lead to further improvement in sensitivity. The step of heating can be carried out on a hot plate or the like, and in the method of manufacturing the device, the step of prebaking corresponds to the step.

The substrate is not particularly limited and a known substrate can be used. For example, a metal substrate such as silicon, silicon nitride, titanium, tantalum, palladium, copper, chromium, aluminum; a glass substrate; and the like can be mentioned.
In one embodiment of the present invention, the active energy rays used for exposure in the photolithography step used to obtain an interlayer insulating film for creating an LSI include UV, KrF excimer laser light, ArF excimer laser light, electron beams, or Extreme ultraviolet rays (EUV) and the like are preferably mentioned.

The irradiation amount of the first active energy ray varies depending on the type and blending ratio of each component in the photocurable composition, the film thickness of the coating film, etc., but is 1 J / cm ² or less or 1000 μC / cm ² or less. Is preferable.
In one aspect of the present invention, the film thickness of the resist film formed by the resist composition is preferably 10 to 200 nm. The resist composition is applied onto a substrate by an appropriate coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc., and is applied at 60 to 150 ° C. for 1 to 20 minutes, preferably 80 to 80 to. Prebake at 120 ° C. for 1-10 minutes to form a thin film. The film thickness of this coating film is 5 to 200 nm, preferably 10 to 100 nm.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

<1> Synthesis of sulfonium salt <Synthesis of sulfonium salt 1>
(Synthesis Example 1) Synthesis of 3- (4-bromobenzoyl) -9-ethylcarbazole 5.1 g of aluminum chloride is added to 48 g of methylene chloride to bring the temperature to 0 ° C. To this, 6.8 g of 9-ethylcarbazole is added, 8.4 g of 4-bromobenzoyl chloride is dissolved in 17 g of methylene chloride, added dropwise over 30 minutes, and then stirred at 25 ° C. for 1 hour. Then, 40 g of pure water is added, and after stirring, the liquid is separated to recover the organic layer. 35 g of pure water was added to the organic layer, 5.2 g of a 25 mass% sodium hydroxide aqueous solution was added while stirring until the aqueous layer became basic, and then the organic layer was recovered and washed 3 times with 40 g of pure water. By distilling off methylene chloride in the organic layer, 8.3 g of 3- (4-bromobenzoyl) -9-ethylcarbazole is obtained.

(Synthesis Example 2) Synthesis of 3-[(4-bromophenyl) dimethoxymethyl] -9-ethylcarbazole 8.0 g of 3- (4-bromobenzoyl) -9-ethylcarbazole and 1.8 g of trimethyl orthoformate are mixed with methanol. After dissolving in 20 g, 200 mg of 95 mass% sulfuric acid is added, and the mixture is stirred at 60 ° C. for 3 hours. After cooling to room temperature and adding 1.0 g of triethylamine, methanol is distilled off. The residue is dissolved in 48 g of methylene chloride, washed 3 times with 32 g of pure water, and the methylene chloride is distilled off to obtain 8.8 g of 3-[(4-bromophenyl) dimethoxymethyl] -9-ethylcarbazole.

(Synthesis Example 3) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldiphenylsulfonium nonaflatebutanesulfonate (sulfonium salt 1) 2.0 g of tetrahydrofuran and 360 mg of magnesium were added to a pre-dried flask. Add 50 mg of 1,2-dibromoethane to activate magnesium. After confirming the activation, the temperature of the solution was raised to 50 ° C., and 4.0 g of 3-[(4-bromophenyl) dimethoxymethyl] -9-ethylcarbazole obtained in Synthesis Example 2 above was added to 6.0 g of THF. The solution dissolved in is dropped. After the dropwise addition, the mixture is stirred at 50 ° C. for 2 hours to obtain a THF solution of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenylmagnesium bromide. 4- [Dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenylmagnesium bromide in a solution of 2.2 g of diphenylsulfoxide, 1.5 g of trimethylsilyl chloride and 1.5 g of triethylamine in 9.5 g of methylene chloride. The THF solution of No. 1 is added dropwise at 10 ° C. or lower, and then the mixture is stirred at 25 ° C. for 1 hour. After stirring, 30 g of a 10 mass% ammonium chloride aqueous solution is added at 5 ° C. or lower, and the mixture is further stirred for 10 minutes. Then, 40 g of methylene chloride and 3.8 g of potassium nonafluorobutanesulfonate are added, and the mixture is stirred at 25 ° C. for 2 hours. Crude crystals are obtained by separating the liquid, washing with pure water three times, and then distilling off methylene chloride. By purifying the crude crystals by silica gel column chromatography (methylene chloride / methanol = 90/10 (volume ratio)), 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldiphenylsulfonium nonaflate butane sulfonate Obtain 4.7 g of (sulfonium salt 1).

<Synthesis of sulfonium salt 2>
(Synthesis Example 4) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldiphenylsulfonium benzoate (sulfonium salt 2) The above except that sodium benzoate is used instead of potassium nonafluorobutanesulfonate. By performing the same operation as in Synthesis Example 3, 3.5 g of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldiphenylsulfoniumbenzoate (sulfonium salt 2) is obtained.

<Synthesis of sulfonium salt 3>
(Synthesis Example 5) Synthesis of 3- [2- (4-bromobenzoyl) -1,3-dioxolane-2-yl] -9-ethylcarbazole Same as Synthetic Example 2 except that ethylene glycol is used instead of methanol. By performing the above procedure, 8.6 g of 3- [2- (4-bromobenzoyl) -1,3-dioxolane-2-yl] -9-ethylcarbazole can be obtained.

(Synthesis Example 6) Synthesis of diphenyl-4- [2- (9-ethylcarbazole-3-yl) -1,3-dioxolan-2-yl] phenylsulfonium nonafluorobutane sulfonate (sulfonium salt 3) 3-[() The above synthesis example except that 3- [2- (4-bromobenzoyl) -1,3-dioxolan-2-yl] -9-ethylcarbazole is used instead of 4-[bromophenyl) dimethoxymethyl] -9-ethylcarbazole. Diphenyl-4- [2- (9-ethylcarbazole-3-yl) -1,3-dioxolan-2-yl] phenylsulfonium nonafluorobutane sulfonate (sulfonium salt 3) was added to 4 by performing the same operation as in 3. Get 5.5g.

<Synthesis of sulfonium salt 4>
(Synthesis Example 7) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldibenzothiophenium nonaflatebutane sulfonate (sulfonium salt 4) Except for using dibenzothiophene oxide instead of diphenyl sulfoxide. By carrying out the same operation as in Synthesis Example 3, 3.1 g of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldibenzothiophenium nonaflate butane sulfonate (sulfonium salt 4) can be obtained.

<Synthesis of sulfonium salt 5>
(Synthetic Example 8) 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldibenzothiophenium-4- (3-hydroxyadamantylcarbonyloxy) -1,1,2-trifluorobutane sulfonate ( Synthesis of Sulfonium Salt 5) Dibenzothiophene oxide was used in place of diphenyl sulfoxide, and 4- (3-hydroxyadamantylcarbonyloxy) -1,1,2-trifluorobutanesulfonic acid was used in place of potassium nonafluorobutanesulfonate. By performing the same operation as in Synthesis Example 3 except that sodium is used, 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldibenzothiophenium-4- (3-hydroxyadamantylcarbonyloxy) Obtain 3.3 g of -1,1,2-trifluorobutane sulfonate (sulfonium salt 5).

<Synthesis of sulfonium salt 6>
(Synthesis Example 9) Synthesis of 3- (4-bromobenzoyl) dibenzothiophene 3- (4-Bromobenzoyl) can be obtained by performing the same operation as in Synthesis Example 1 above except that dibenzothiophene is used instead of 9-ethylcarbazole. Obtain 8.1 g of dibenzothiophene.

(Synthesis Example 10) Synthesis of 3-[(4-Bromophenyl) dimethoxymethyl] dibenzothiophene Except for the use of 3- (4-bromobenzoyl) dibenzothiophene instead of 3- (4-bromobenzoyl) -9-ethylcarbazole. Obtains 8.6 g of 3-[(4-bromophenyl) dimethoxymethyl] dibenzothiophene by performing the same operation as in Synthesis Example 2 above.

(Synthesis Example 11) Synthesis of 4-[(dibenzothiophen-3-yl) dimethoxymethyl] phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 6) 3-[(4-Bromophenyl) dimethoxymethyl] -9-ethylcarbazole 4-[(Dibenzothiophen-3-yl) dimethoxymethyl] phenyldiphenylsulfonium by performing the same operation as in Synthesis Example 3 above except that 3-[(4-bromophenyl) dimethoxymethyl] dibenzothiophene is used instead of Obtain 4.5 g of nonafluorobutane sulfonate (sulfonium salt 6).

<Synthesis of sulfonium salt 7>
(Synthesis Example 12) Synthesis of 3- (4-bromobenzoyl) dibenzofuran 3- (4-Bromobenzoyl) dibenzofuran can be obtained by performing the same operation as in Synthesis Example 1 above except that dibenzofuran is used instead of 9-ethylcarbazole. Obtain 8.1 g.

(Synthesis Example 13) Synthesis of 3-[(4-bromophenyl) dimethoxymethyl] dibenzofuran The above except that 3- (4-bromobenzoyl) dibenzofuran is used instead of 3- (4-bromobenzoyl) -9-ethylcarbazole. By performing the same operation as in Synthesis Example 2, 8.4 g of 3-[(4-bromophenyl) dimethoxymethyl] dibenzofuran is obtained.

(Synthesis Example 14) Synthesis of 4-[(dibenzofuran-3-yl) dimethoxymethyl] phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 7) to 3-[(4-bromophenyl) dimethoxymethyl] -9-ethylcarbazole By performing the same operation as in Synthesis Example 3 above except that 3-[(4-bromophenyl) dimethoxymethyl] dibenzofuran is used instead, 4-[(dibenzofuran-3-yl) dimethoxymethyl] phenyldiphenylsulfonium nonafluorobutane Obtain 4.1 g of sulfonate (sulfonium salt 7).

<Synthesis of sulfonium salt 8>
(Synthesis Example 15) Synthesis of 4- (4-bromobenzoyl) phenylmethylphenylamine By performing the same operation as in Synthesis Example 1 above except that diphenylmethylamine is used instead of 9-ethylcarbazole, 4- (4- (4-bromobenzoyl) is performed. Obtain 8.0 g of bromobenzoyl) phenylmethylphenylamine.

(Synthesis Example 16) Synthesis of 4-[(4-Bromophenyl) Dimethoxymethyl] Phenylmethylphenylamine 4- (4-Bromobenzoyl) phenylmethylphenyl instead of 3- (4-bromobenzoyl) -9-ethylcarbazole 8.2 g of 4-[(4-bromophenyl) dimethoxymethyl] phenylmethylphenylamine can be obtained by carrying out the same operation as in Synthesis Example 2 except that an amine is used.

(Synthesis Example 17) Synthesis of 4- [dimethoxy- [4- (methylphenylamino) phenyl] methyl] phenyldiphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 8) 3-[(4-Bromophenyl) dimethoxymethyl] -9 By performing the same operation as in Synthesis Example 3 above except that 4-[(4-bromophenyl) dimethoxymethyl] methylphenylamine is used instead of −ethylcarbazole, 4- {dimethoxy- [4- (methylphenylamino)) 3.9 g of phenyl] methyl} phenyldiphenylsulfonium nonafluorobutane sulfonate (sulfonium salt 8) is obtained.

<Synthesis of sulfonium salt 9>
(Synthesis Example 18) Synthesis of 9-ethyl-3- (4-phenylsulfanylbenzoyl) carbazole 46 g of 3- (4-bromobenzoyl) -9-ethylcarbazole, 20 g of benzenethiol and 25 g of calcium carbonate were added to N, N-dimethyl. Add to 117 g of formamide (DMF) and stir at 60 ° C. for 5 hours. Then, 312 g of pure water and 312 g of ethyl acetate are added to separate the liquids, and the organic layer is recovered. The organic layer is washed twice with 150 g of pure water and ethyl acetate is distilled off to obtain crude crystals. After dispersing it in 150 g of isopropyl ether, it is recovered to obtain 40 g of 9-ethyl-3- (4-phenylsulfanylbenzoyl) carbazole.

(Synthesis Example 19) Synthesis of 9-ethyl-3- (4-phenylsulfinylbenzoyl) carbazole After dissolving 38 g of 9-ethyl-3- (4-phenylsulfanylbenzoyl) carbazole in 228 g of formic acid, 35 mass% hydrogen peroxide Add 9.0 g of water and stir at room temperature for 17 hours. The reaction solution is added dropwise to 1100 g of pure water, and the generated crude crystals are recovered. After dissolving the crude crystals in 228 g of methylene chloride, 152 g of pure water is added, and 20 g of a 25 mass% sodium hydroxide aqueous solution is added while stirring until the aqueous layer becomes basic. Crude crystals are obtained by washing the organic layer with 132 g of pure water and then distilling off methylene chloride. The crude crystals are dispersed in 152 g of diisopropyl ether and then recovered to obtain 36 g of 9-ethyl-3- (4-phenylsulfinylbenzoyl) carbazole.

(Synthesis Example 20) Synthesis of 3- [dimethoxy- (4-phenylsulfinylphenyl) methyl] -9-ethylcarbazole 9-ethyl-3- (4) instead of 3- (4-bromobenzoyl) -9-ethylcarbazole 9.0 g of 3- [dimethoxy- (4-phenylsulfinylphenyl) methyl] -9-ethylcarbazole can be obtained by performing the same operation as in Synthesis Example 2 except that −phenylsulfinylbenzoyl) carbazole is used.

(Synthesis Example 21) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-fluorophenylphenylsulfonium nonaflatebutane sulfonate (sulfonium salt 9) tetrahydrofuran 2. In a pre-dried flask. Add 0 g and 330 mg magnesium. 1.4 g of 1-bromo-4-fluorobenzene is added dropwise thereto. After the dropwise addition, the mixture is stirred at 50 ° C. for 1 hour to obtain a THF solution of 4-fluorophenylmagnesium bromide. 4-Fluorophenylmagnesium bromide in a solution of 2.0 g of 3- [dimethoxy- (4-phenylsulfinylphenyl) methyl] -9-ethylcarbazole and 920 mg of trimethylsilyl chloride obtained in Synthesis Example 20 in 10 g of tetrahydrofuran. The THF solution of No. 1 is added dropwise at 10 ° C. or lower, and then the mixture is stirred at 25 ° C. for 1 hour. After stirring, 860 mg of triethylamine is added, 30 g of a 10 mass% ammonium chloride aqueous solution is added at 5 ° C. or lower, the mixture is further stirred for 10 minutes, 7.0 g of ethyl acetate is added and the solution is separated to recover the organic layer. After distilling off tetrahydrofuran and ethyl acetate, 15 g of methylene chloride, 10 g of pure water and 1.7 g of potassium nonafluorobutanesulfonate are added, and the mixture is stirred at 25 ° C. for 2 hours. Crude crystals are obtained by separating the liquid, washing with pure water three times, and then distilling off methylene chloride. By purifying the crude crystals by silica gel column chromatography (methylene chloride / methanol = 90/10 (volume ratio)), 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-fluorophenylphenyl Obtain 2.1 g of sulfonium nonaflate butane sulfonate (sulfonium salt 9).

<Synthesis of sulfonium salt 10>
(Synthesis Example 22) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-fluorophenylphenylsulfonium-p-styrene sulfonate (sulfonium salt 10) in place of potassium nonafluorobutanesulfonate 4- [Dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-fluorophenylphenylsulfonium-p by performing the same operation as in Synthesis Example 21 except that sodium p-styrene sulfonate is used. -Provide 2.1 g of styrene sulfonate (sulfonium salt 10).

<Synthesis of sulfonium salt 11>
(Synthesis Example 23) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-methylsulfanylphenylphenylsulfonium nonafluorobutanesulfonate 1- instead of 1-bromo-4-fluorobenzene By performing the same operation as in Synthesis Example 21 except that bromo-4-methylsulfanylbenzene is used, 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-methylsulfanylphenylphenylsulfonium nona Obtain 2.2 g of fluorobutane sulfonate.

(Synthesis Example 24) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-methylsulfonylphenylphenylphenylsulfonium nonafluorobutanesulfonate (sulfonium salt 11) 4 obtained in Synthesis Example 23 above. -[Dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-methylsulfanylphenylphenylsulfonium nonafluorobutane sulfonate 200 mg is dissolved in 1.2 g of formic acid, and then 60 mg of 35% by mass hydrogen peroxide solution is added. Then, stir at 60 ° C. for 17 hours. 10 g of dichloromethane and 6 g of pure water are added to the reaction solution, and the organic layer is recovered. After distilling off dichloromethane, 10 g of methanol and 10 mg of sulfuric acid are added, and the mixture is stirred at 60 ° C. for 3 hours. After cooling to room temperature and adding 23 mg of triethylamine, methanol is distilled off. The residue was dissolved in 10 g of methylene chloride, washed 3 times with 6 g of pure water, and the methylene chloride was distilled off to obtain 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-methylsulfonyl. 200 mg of phenylphenylsulfonium nonaflate butane sulfonate (sulfonium salt 11) is obtained.

<Synthesis of sulfonium salt 12>
(Synthesis Example 25) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4- (1-ethoxyethoxy) phenylphenylsulfonium phenyl sulfonate Synthesis of phenyl sulfone instead of potassium nonafluorobutane sulfonate 4- [Dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4- (1-ethoxyethoxy) phenylphenylsulfonium camphorsulfonate is performed in the same manner as in Synthesis Example 21 except that sodium acid is used. To obtain 2.0 g.

(Synthesis Example 26) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-hydroxyphenylphenylsulfonium camphorsulfonate (sulfonium salt 12) 4- [dimethoxy- (9-ethylcarbazole-) 3-Il) Methyl] phenyl-4- (1-ethoxyethoxy) phenylphenylsulfonium After dissolving 2.0 g of phenylsulfonium in 20 g of methanol, 100 mg of phenylsulfonic acid is added, and the mixture is stirred at 60 ° C. for 3 hours. After cooling to room temperature and adding 5 g of a 1 mass% sodium hydroxide aqueous solution, methanol is distilled off. The residue was dissolved in 48 g of methylene chloride, washed 3 times with 32 g of pure water, and the methylene chloride was distilled off to obtain 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-4-hydroxyphenyl. Obtain 1.4 g of phenylsulfonium camphorsulfonate (sulfonium salt 12).

<Synthesis of sulfonium salt 13>
(Synthesis Example 27) Synthesis of 3- [4- (Methylphenylamino) Phenylcarbonyl] Dibenzothiophene By performing the same operation as in Synthesis Example 18 except that N-methylaniline is used instead of benzenethiol, 3- [4 -(Methylphenylamino) Phenylcarbonyl] Obtain 28 g of dibenzothiophene.

(Synthesis Example 28) Synthesis of 3- [4- (methylphenylamino) phenylcarbonyl] dibenzothiophene-9-oxide 3- [4- (methyl) instead of 9-ethyl-3- (4-phenylsulfanylbenzoyl) carbazole 20 g of 3- [4- (methylphenylamino) phenylcarbonyl] dibenzothiophene-9-oxide is obtained by performing the same operation as in Synthesis Example 19 except that phenylamino) phenylcarbonyl] dibenzothiophene is used.

(Synthesis Example 29) Synthesis of 3- [dimethoxy-4- (methylphenylamino) phenylmethyl] dibenzothiophene-9-oxide 3- [4-(4) instead of 3- (4-bromobenzoyl) -9-ethylcarbazole By performing the same operation as in Synthesis Example 2 except that methylphenylamino) phenylcarbonyl] dibenzothiophene-9-oxide is used, 3- [dimethoxy-4- (methylphenylamino) phenylmethyl] dibenzothiophene-9-oxide can be obtained. Get 20g.

(Synthesis Example 30) Synthesis of phenyl-3- [dimethoxy- (4-methylphenylamino) phenylmethyl] dibenzothiophenium nonafluorobutane sulfonate (sulfonium salt 13) 3- [dimethoxy- (4-phenylsulfinylphenyl) methyl ] -9-Ethylcarbazole is replaced by 3- [dimethoxy-4- (methylphenylamino) phenylmethyl] dibenzothiophene-9-oxide, and 1-bromo-4-fluorobenzene is replaced by bromobenzene. By performing the same operation as in Synthesis Example 21, 3.1 g of phenyl-3- [dimethoxy- (4-methylphenylamino) phenylmethyl] dibenzothiophenium nonafluorobutane sulfonate (sulfonium salt 13) is obtained.

<Synthesis of sulfonium salt 14>
(Synthesis Example 31) Synthesis of diphenyl-4- (9-ethylcarbazole-3-ylcarbonyl) phenylsulfonium-4-methacryloxy-1,1,2-trifluorobutanesulfonate 4-instead of potassium nonafluorobutanesulfonate Diphenyl-4- (9-ethylcarbazole-3-ylcarbonyl) phenylsulfonium-4-methacryloxy by performing the same operation as in Synthesis Example 21 above except that sodium methacryloxy 1,1,2-trifluorobutanesulfonate is used. Obtain 1.5 g of -1,1,2-trifluorobutane sulfonate.

<Synthesis of sulfonium salt 15>
(Synthesis Example 32) Synthesis of 4-methylsulfanylbenzoyl chloride Add 148 g of thionyl chloride to 24.7 g of 4-methylsulfanylbenzoic acid and stir at 60 ° C. for 4 hours. After stirring, thionyl chloride is distilled off under reduced pressure to obtain 27.5 g of 4-methylsulfanylbenzoyl chloride.

(Synthesis Example 33) Synthesis of 9-ethyl-3- (4-methylsulfanylbenzoyl) carbazole By performing the same operation as in Synthesis Example 1 except that 4-methylsulfanylbenzoylchloride is used instead of 4-bromobenzoylchloride. Obtain 34 g of 9-ethyl-3- (4-methylsulfanylbenzoyl) carbazole.

(Synthesis Example 34) Synthesis of dimethyl-4- (9-ethylcarbazole-3-ylcarbonyl) phenylsulfonium nonafluorobutanesulfonate 9-ethyl-3- (4-methylsulfanylbenzoyl) carbazole obtained in the above Synthesis Example 33 1.0 g is dissolved in 7.0 g of acetonitrile, 920 mg of dimethylsulfonium is added thereto, and the mixture is stirred at 70 ° C. for 4 hours. After stirring, 20 g of pure water is added, the mixture is further stirred for 10 minutes, and 13 g of toluene is added for washing. To the obtained aqueous layer, 1.5 g of potassium nonafluorobutanesulfonate and 10 g of methylene chloride are added, and the mixture is stirred for about 1 hour. Crude crystals are obtained by separating the liquid, washing with water three times, and then distilling off methylene chloride. By purifying the crude crystals by silica gel column chromatography (methylene chloride / methanol = 90/10 (volume ratio)), dimethyl-4- (9-ethylcarbazole-3-ylcarbonyl) phenylsulfonium nonaflate butane sulfonate was obtained. Get 6g.

(Synthesis Example 35) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyldimethylsulfonium nonaflate butane sulfonate (sulfonium salt 15) to 3- (4-bromobenzoyl) -9-ethylcarbazole By performing the same operation as in Synthesis Example 2 above except that dimethyl-4- (9-ethylcarbazole-3-ylcarbonyl) phenylsulfonium nonaflatebutanesulfonate is used instead, 4- [dimethoxy- (9-ethylcarbazole-) 3-Il) Methyl] phenyldimethylsulfonium Nonaflate butane sulfonate (sulfonium salt 15) 1.7 g is obtained.

<Synthesis of iodonium salt 1>
(Synthesis Example 36) Synthesis of 9-ethyl-3- (4-iodobenzoyl) carbazole By performing the same operation as in Synthesis Example 1 above except that 4-iodobenzoyl chloride is used instead of 4-bromobenzoyl chloride. Obtain 9.1 g of -ethyl-3- (4-iodobenzoyl) carbazole.

(Synthesis 37) Synthesis of 4- (9-ethylcarbazole-3-ylcarbonyl) phenylphenyliodonium nonafluorobutane sulfonate 9-ethyl-3- (4-iodobenzoyl) carbazole obtained in Synthesis Example 36 in 16 g of sulfuric acid Add 4 g, then add 10 g of potassium persulfate little by little at 10 ° C. or lower and stir for 30 minutes. After stirring, 9.8 g of benzene is added and the mixture is further stirred at 25 ° C. for 3 hours. After stirring, 30 g of pure water is added at 10 ° C. or lower, then 40 g of methylene chloride and 4.7 g of potassium nonafluorobutanesulfonate are added, and the mixture is stirred at 25 ° C. for about 2 hours. This is separated and washed with water three times, and then methylene chloride is distilled off to obtain a crude product. 4.5 g of 4- (9-ethylcarbazole-3-ylcarbonyl) phenylphenyliodonium nonaflate butane sulfonate by purifying the crude product by silica gel column chromatography (methylene chloride / methanol = 90/10 (volume ratio)). obtain.

(Synthesis Example 38) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenylphenyliodonium nonafluorobutanesulfonate (iodonium salt 1) to 3- (4-bromobenzoyl) -9-ethylcarbazole By performing the same operation as in Synthesis Example 2 above except that 4- (9-ethylcarbazole-3-ylcarbonyl) phenylphenyliodonium nonafluorobutanesulfonate is used instead, 4- [dimethoxy- (9-ethylcarbazole-3) -Methyl] Phenylphenyliodonium Nonafluorobutane sulfonate (iodonium salt 1) is obtained in 4.2 g.

<Synthesis of iodonium salt 2>
(Synthesis Example 39) Synthesis of 4- (9-ethylcarbazole-3-ylcarbonyl) phenyl-2,4,6-trimethylphenyliodonium nonafluorobutane sulfonate Same as Synthetic Example 38 except that mesitylene is used instead of benzene. By carrying out the above procedure, 4.4 g of 4- (9-ethylcarbazole-3-ylcarbonyl) phenyl-2,4,6-trimethylphenyliodonium nonafluorobutane sulfonate can be obtained.

(Synthesis Example 40) Synthesis of 4- [dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-2,4,6-trimethylphenyliodonium nonafluorobutanesulfonate (iodonium salt 2) 3- (4-bromo) The same operation as in Synthesis Example 2 above, except that 4- (9-ethylcarbazole-3-ylcarbonyl) phenyl-2,4,6-trimethylphenyliodonium nonafluorobutane sulfonate is used instead of benzoyl) -9-ethylcarbazole. 4- [Dimethoxy- (9-ethylcarbazole-3-yl) methyl] phenyl-2,4,6-trimethylphenyliodonium nonafluorobutane sulfonate (iodonium salt 1) is obtained in an amount of 4.6 g.

<Synthesis of Polymer A>
(Synthesis Example 41) Synthesis of Polymer A 8.0 g of polyhydroxystyrene (weight average molecular weight 8000) and 0.010 g of a 35 mass% hydrochloric acid aqueous solution are dissolved in 28 g of dehydrated dioxane. 2.73 g of cyclohexyl vinyl ether is dissolved therein in 2.80 g of dehydrated dioxane and added dropwise to the polyhydroxystyrene solution over 30 minutes. After dropping, the mixture is stirred at 40 ° C. for 2 hours. After stirring and cooling, 0.014 g of dimethylaminopyridine is added. Then, the polymer is precipitated by dropping the solution into 260 g of pure water. This is separated by vacuum filtration, and the obtained solid is washed twice with 300 g of pure water and then vacuum dried to obtain 9.2 g of the polymer A shown below as a white solid. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of polymer B>
(Synthesis Example 42) Synthesis of Polymer B 7.0 g of acetoxystyrene, 3.1 g of t-butyl methacrylate, 0.022 g of butyl mercaptan, and dimethyl-2,2'-azobis (2-methylpropionate) (AIBN) 0. 40 g and 40 g are dissolved in 35 g of tetrahydrofuran (THF) to deoxidize. This is added dropwise over 20 g of THF, which has been set to a reflux temperature by nitrogen airflow in advance, over 4 hours. After dropping, the mixture is stirred for 2 hours and then cooled to room temperature. The polymer is precipitated by dropping this into a mixed solvent of 149 g of hexane and 12 g of THF. This is separated by vacuum filtration, and the obtained solid is washed with 52 g of hexane and then vacuum dried to obtain 10.3 g of polymer B represented by the following formula as a white solid. The weight average molecular weight determined by polystyrene conversion using gel permeation chromatography is 9200. The monomer ratio of the polymer unit in the present invention is not limited to the following.

(Synthesis Example 43) Synthesis of Polymer C 6.0 g of polymer B, 6.0 g of triethylamine, 6.0 g of methanol and 1.5 g of pure water are dissolved in 30 g of propylene glycol monomethyl ether and stirred at a reflux temperature for 6 hours. Then, the mixture is cooled to 25 ° C., and the obtained solution is added dropwise to a mixed solution of 30 g of acetone and 30 g of pure water to precipitate the polymer. This is separated by vacuum filtration, and the obtained solid is washed twice with 30 g of pure water and then vacuum dried to obtain 4.3 g of polymer C represented by the following formula as a white solid. The weight average molecular weight determined by polystyrene conversion using gel permeation chromatography is 9100. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of Polymer D>
(Synthesis Example 44) Synthesis of Polymer D 5.0 g of α-methacrylicyloxy-γ-butyrolactone, 6.0 g of 2-methyladamantan-2-methacrylate, 4.3 g of 3-hydroxyadamantane-1-methacrylate, and dimethyl-2,2 0.51 g of'-azobis (2-methylpropionate) and 26 g of propylene glycol-1-monomethyl ether acetate (PGMEA) are dissolved and deoxidized. This is added dropwise to 7.5 g of PGMEA preheated to 85 ° C. over 4 hours. After stirring for 2 hours, cool. After cooling, it is reprecipitated by dropping it on 180 g of hexane. This is filtered, dispersed and washed with 70 g of hexane, filtered again, and then vacuum dried to obtain 8.5 g of polymer D represented by the following formula as a compound that reacts with an acid. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of Polymer E>
(Synthesis Example 45) Synthesis of Polymer E
10.1 g of the polymer E represented by the following formula can be obtained by performing the same operation as in Synthesis Example 42 except that pt-butoxystyrene is used instead of t-butyl methacrylate. The monomer ratio of the polymer unit in the present invention is not limited to the following.

(Synthesis Example 46) Synthesis of Polymer F 4.1 g of Polymer F represented by the following formula can be obtained by performing the same operation as in Synthesis Example 43 except that Polymer E is used instead of Polymer B. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of polymer G>
(Synthesis Example 47) Synthesis of Polymer G 5.5 g of 5-methacryloyloxynorbornane 2,6-lactone, 6.2 g of 4- (1-ethoxyethoxy) phenyl methacrylate and 4.4 g of 4-hydroxyphenyl methacrylate are used as monomers. Except for this, 8.0 g of polymer G represented by the following formula can be obtained by performing the same operation as in Synthesis Example 44. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of Polymer H>
(Synthesis Example 48) Synthesis of Polymer H 1-acetoxy-4-vinylnaphthalene is used instead of acetoxystyrene, and 1- (2-tetrahydropyranyloxy) -4-vinylnaphthalene is used instead of t-butyl methacrylate. 10.5 g of polymer H represented by the following formula is obtained by performing the same operation as in Synthesis Example 42 except that it is used. The monomer ratio of the polymer unit in the present invention is not limited to the following.

(Synthesis Example 49) Synthesis of Polymer I 4.3 g of Polymer I represented by the following formula can be obtained by performing the same operation as in Synthesis Example 43 except that Polymer H is used instead of Polymer B. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of Polymer J>
(Synthesis Example 50) Synthesis of Polymer J The following formula can be obtained by performing the same operation as in Synthesis Example 44 except that 2-methacrylic oxy-1,3-propane sultone is used instead of α-methacrylic acid-γ-butyrolactone. Obtain 8.0 g of the polymer J shown in. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of Polymer K>
(Synthesis Example 51) Synthesis of Polymer K 2-Methacrylicoxy-1,3-propanesultone is used instead of α-methacrylicoxy-γ-butyrolactone, and 2-methyladamantan-2-methacrylate is replaced with 1-ethoxyethyl methacrylate. 8.2 g of the polymer K represented by the following formula can be obtained by performing the same operation as in Synthesis Example 44 except for the use of. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of polymer L>
(Synthesis Example 52) Synthesis of Polymer L As monomers, 7.2 g of 5-methacryloyloxynorbornane 2,6-sultone and 2- (1-ethoxyethoxy) -6-vinylnaphthalene 5.9 g and 2-hydroxy-6-vinylnaphthalene 8.0 g of the polymer L represented by the following formula is obtained by performing the same operation as in Synthesis Example 44 except that 3.0 g is used. The monomer ratio of the polymer unit in the present invention is not limited to the following.

<Synthesis of Polymer M>
(Synthesis Example 53) Synthesis of Polymer M 4.7 g of the sulfonium salt 14 obtained in the above Synthesis Example 31 as a monomer, 3.9 g of 5-methacryloyloxynorbornane 2,6-lactone and 4- (1-ethoxyethoxy) phenyl methacrylate 7.8 g of the polymer M represented by the following formula is obtained by performing the same operation as in Synthesis Example 44 except that 4.2 g and 3.2 g of 4-hydroxyphenyl methacrylate are used. The monomer ratio of the polymer unit in the present invention is not limited to the following.

[Examples 1 to 7 and Comparative Examples 1 to 2]
<Electron beam sensitivity evaluation 1>
Samples were prepared as follows. Cyclohexanone 3000 mg, 500 mg of any resin selected from the above polymers A, C, D, J, K and M, and one or more selected from photoacid generators (PAG) and sensitizing compounds are appropriately selected. The composition samples 1 to 9 were prepared by adding 0.036 mmol and an acid diffusion control agent at a ratio of 0.0012 mmol, respectively.
As the photoacid generator (PAG), the above sulfonium salts 1 and 4 and the comparative sulfonium salts 1 and 2 shown below were used. As the comparative sulfonium salt 1, the comparative sensitizing compound 1'was also used.
Trioctylamine was used as the acid diffusion control agent.

The electron beam sensitivity is evaluated as follows. The resist composition sample 1 is spin-coated on a silicon wafer previously modified with hexamethylene disilazane. This is prebaked on a hot plate at 110 ° C. for 1 minute to obtain a substrate on which a coating film having a thickness of 200 nm is formed. The coating film of the substrate is drawn with an electron beam of 30 keV so as to have a line and space pattern of 200 nm using an electron beam drawing apparatus. After performing PEB for 30 seconds on a hot plate at 60 ° C. after electron beam irradiation, the substrate was exposed to the entire surface with an exposure amount of 500 mJ / cm ² by a UV exposure apparatus (355 nm to 410 nm), and then at 110 ° C. on the hot plate. Heat for 1 minute. Develop for 1 minute with a developer (product name: NMD-3, 2.38% by mass aqueous solution of tetramethylammonium hydroxide, manufactured by Tokyo Ohka Kogyo Co., Ltd.), and then rinse with pure water to form a 200 nm line. Get an and space pattern. The electron beam irradiation amount at this time is set to E _size [μC / cm ² ], and the sensitivity by electron beam irradiation is obtained. Sensitivity evaluation is also performed on the other samples 2 to 9 in the same manner as described above. The sample composition and results are shown in Table 1.

In Table 1, the sensitivity of each sample is such that the sensitivity of sample 8 (Comparative Example 1) to which the comparative sulfonium salt 1 and the comparative sensitizing compound 1'was added is 100, and the samples (Examples 1 to 7 and Comparative Example) with respect to the sensitivity are set to 100. The evaluation result of 2) was calculated as a relative value. The smaller the value of the sensitivity, the better the effect.

Examples 1 to 7, which are samples containing an onium salt according to some aspects of the present invention in any of the polymers, are described in Comparative Example 1 and Comparative Example 2 (Sample 9 of Comparative Example 2 is described in, for example, WO2018 / 074382. It was found that the sensitivity after UV irradiation was higher than that of the sample containing one of the disclosed onium salts). The following are possible reasons. It is considered that the sulfonium salt 1 and the sulfonium salt 4 have higher absorption near the UV wavelength (> 365 nm) than the comparative sulfonium salt 2, and the sensitivity after UV irradiation is higher. It is presumed that the high absorption of the sulfonium salt 1 and the sulfonium salt 4 near the UV wavelength is due to having an amino group and a condensed ring structure.
FIG. 1 shows the UV absorption coefficient of the sulfonium salt 1 and the comparative sulfonium salt 2. As shown in FIG. 1, the sulfonium salt 1 absorbs more at the UV wavelength than the comparative sulfonium salt 2. As the UV absorption coefficient increases, the acid generation efficiency due to UV irradiation improves, so the sensitivity increases.

Since the sulfonium salt 8 has an amino group, the absorption near the UV wavelength is higher than that of the comparative sulfonium salt 2 as in the sulfonium salt 1, and the sensitivity after UV irradiation is high.
Further, since the sulfonium salt 6 and the like also have a fused ring structure of oxygen atoms and sulfur atoms, the absorption near the UV wavelength is higher than that of the comparative sulfonium salt 2 like the sulfonium salt 1, and after UV irradiation The sensitivity is high.

According to some aspects of the present invention, the onium salt is structurally changed to a ketone derivative by an active species generated by irradiation with an electron beam or extreme ultraviolet rays, and the ketone derivative is converted into a ketone derivative by irradiation with a second active energy ray. A resin composition containing an onium salt capable of generating the above can be provided. When the onium salt has a specific substituent or a specific structure, specifically, an amino group or a heterocondensate structure improves the absorption of the UV wavelength to be irradiated. Therefore, the resin composition containing the onium salt can be a highly sensitive resist composition that efficiently generates an acid by UV irradiation.

Claims (14)

An onium salt represented by any of the following general formula (1) and the following general formula (2).
(In the above formula (1), R ¹¹ and R ¹² each have a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms; which may independently have a substituent. It may have a linear, branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and having a substituent. A heteroaryl group having 4 to 12 carbon atoms; whichever is selected from the group consisting of
Any two or more of the aryl groups to which the R ¹¹ , R ¹² and the sulfonium group are bonded are selected directly by a single bond or from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. A ring structure may be formed with the sulfur atom to which they are bonded via either of them.
At least one methylene group in R ¹¹ and R ¹² may be substituted with a divalent heteroatom-containing group.
R ¹³ and R ¹⁴ independently have an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, respectively. Alkyl sulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, (meth) acryloyloxy group, hydroxy (poly) alkyleneoxy group, amino group, cyano It is one selected from the group consisting of a group, a nitro group, and a halogen atom, and when it has carbon, the number of carbon atoms is 1 to 12, and these may have a substituent.
At least one of R ¹⁴ is an amino group, or R ¹⁴ is selected from the group consisting of an oxygen atom, a sulfur atom and a nitrogen atom containing group, and the R ¹⁴ is attached to each other together with an aryl group to which the R ¹⁴ is attached. It forms a heterocyclic structure and
R ¹⁵ and R ¹⁶ are linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, each of which may independently have a substituent; and may have a substituent. A branched or cyclic alkenyl group having 1 to 12 carbon atoms; an aryl group having 6 to 14 carbon atoms which may have a substituent; and an aryl group having 4 to 12 carbon atoms which may have a substituent. Heteroaryl group; one selected from the group consisting of
The R ¹⁵ and R ¹⁶ may be bonded to each other to form a ring structure either directly by a single bond or via any one selected from the group consisting of an oxygen atom, a sulfur atom and an alkylene group.
At least one methylene group in R ¹⁵ and R ¹⁶ may be substituted with a divalent heteroatom-containing group.
L ¹ is a direct bond; a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms; an alkenylene group having 1 to 12 carbon atoms; an arylene group having 6 to 14 carbon atoms; a carbon atom number of 4 to 12 Heteroarylene group; and a group to which these groups are bonded via an oxygen atom, a sulfur atom, or a nitrogen atom-containing group;
L ⁴ and L ⁵ are each independently selected from the group consisting of a direct bond, an alkenylene group having 2 carbon atoms, an alkynylene group having 2 carbon atoms, and a carbonyl group.
Y is an oxygen atom or a sulfur atom,
h and i are independently integers 1 to 3 respectively.
j is an integer of 0 to 4 when h is 1, 0 to 6 when h is 2, and 0 to 8 when h is 3.
k is an integer of 0 to 5 when i is 1, 0 to 7 when i is 2, and 0 to 9 when i is 3.
X ⁻ represents a monovalent counter anion.
In the above formula (2),
R ^{13 to} R ¹⁶ , L ¹ , L ^{4 to} L ⁵ , Y, h to k, and X ^- are independent of each other, respectively, from R ^{13 to} R ¹⁶ , L ¹ , L ^{4 to} L ⁵ of the above formula (1). , Y, h to k and X ^- is selected from the same options as each
R ¹⁷ is one selected from the group consisting of an aryl group which may have a substituent; and a heteroaryl group which may have a substituent, and R ¹⁷ and an iodonium group are bonded to each other. Aryl groups may be bonded to each other to form a ring structure with iodine atoms to which they are bonded. ) The onium salt according to claim 1, which is represented by the following general formula (3).
(In the above formula (3),
R ^{13 to} R ¹⁶ , Y and X ⁻ are independently selected from the same options as R ^{13 to} R ¹⁶ , Y and X ⁻ of the above formula (1), respectively.
R ¹⁸ is an alkyl group, a hydroxy group, a mercapto group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an alkylsulfanyl group, an arylsulfanyl group, an aryl group, or a hetero. From aryl groups, aryloxy groups, alkylsulfinyl groups, arylsulfinyl groups, alkylsulfonyl groups, arylsulfonyl groups, (meth) acryloyloxy groups, hydroxy (poly) alkyleneoxy groups, amino groups, cyano groups, nitro groups and halogen atoms The number of carbon atoms in the case of having carbon is 1 to 12, and these may have substituents.
L ² and L ³ are independently selected from the group consisting of a direct bond; a methylene group; an oxygen atom; a sulfur atom; a nitrogen atom-containing group; and the methylene group has a substituent. However, one of L ² and L ³ may be either an oxygen atom, a sulfur atom, or a nitrogen atom-containing group.
e is an integer from 0 to 4
f is an integer from 0 to 3
g is an integer from 0 to 4. ) A photoacid generator containing at least the onium salt according to any one of claims 1 or 2. A composition comprising the photoacid generator according to claim 3 and an acid-reactive compound. The composition according to claim 4, further comprising an acid diffusion control agent. The acid-reactive compound is a resin (B) whose solubility in a developing solution changes due to the action of an acid.
The composition according to claim 4 or 5, wherein the resin (B) has at least one of the units represented by the following (4a) to (4d).
(In the above formula (4a),
R ¹ is ^one selected from the group consisting of a hydrogen atom, an alkyl group and an alkyl halide group.
R ² and R ³ are independently linear, branched or cyclic alkyl groups, respectively.
R ⁴ is a linear, branched or cyclic alkyl group which may have a substituent and
Two or more of the above R ² , R ³ and R ⁴ are either directly in a single bond or selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. , May form a ring structure,
L ⁶ is selected from the group consisting of a direct bond, a carbonyloxy group, a carbonylamino group, a linear, branched or cyclic alkylenecarbonyloxy group which may have a substituent, and an alkylenecarbonylamino group. Is.
In the formula (4b), R ¹ and L ⁶ are selected from the same options as each of the R ¹ and L ^{6 in} the formula (4a).
R ⁵ and R ⁶ are each independently selected from the group consisting of a hydrogen atom and a linear, branched or cyclic alkyl group.
R ⁷ is a linear, branched or cyclic alkyl group which may have a substituent and
Two or more of the above R ⁵ , R ⁶ and R ⁷ are either directly in a single bond or selected from the group consisting of an oxygen atom, a sulfur atom, a nitrogen atom-containing group and a methylene group. , A ring structure may be formed.
In the formula ^(4c), R 1 ~R ⁴ and ^{L 6} are selected from the same options as each of ^R 1 to R ⁴ and ^{L 6} in the formula (4a),
R ⁸ independently consists of a group consisting of an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an alkylsulfanyl group, an alkylsulfinyl group, an alkylsulfonyl group, an amino group, a cyano group, a nitro group, and a halogen atom. Is one of the choices
Two or more of R ⁸ is a direct single bond or an oxygen atom, a sulfur atom, via any one selected from the group consisting of nitrogen atom-containing group and a methylene group, to form a ring structure Often,
l is an integer of 1-2
m is an integer of 0 to 4 when l is 1 and 0 to 6 when l is 2.
n is an integer of 1 to 5 when l is 1, and 1 to 7 when l is 2.
m + n is 1 to 5 when l is 1, and 1 to 7 when l is 2.
In the formula (4d), R ¹ , R ^{5 to} R ⁷ , R ⁸ , L ⁶ , l and n are R ¹ , R ^{5 to} R ⁷ , R ⁸ , L in the formulas (4a) to (4c). It is selected from the same options as each of ⁶ , l and n. ) The resin (B) contains at least one of the units represented by the following general formulas (5a) to (5b), or
The composition according to claim 6, wherein the composition further comprises a resin (C) containing at least one of the units represented by the following general formulas (5a) to (5b).
(In the formula (5a), R ¹ , R ⁸ and L ⁶ are independently selected from the same options as each of the R ¹ , R ⁸ and L ^{6 in} the formula (4a).
p is an integer from 0 to 4, and q is an integer from 1 to 5.
In the formula (5b), R ¹ and L ⁶ are independently selected from the same options as each of the R ¹ and L ^{6 in} the formula (4a).
R ⁹ is a cyclic group containing at least one selected from the group consisting of -C (O) -O-, -SO _2- and -O-SO _2- . ) The composition according to any one of claims 4 to 7, wherein the photoacid generator is an acid generator unit-containing resin in which X ⁻ in the onium salt has a unit represented by the following general formula (6). Stuff.
(In the equation (6), R ¹ and L ⁶ are independently selected from the same options as R ¹ and L ^{6 in} the equation (4a), respectively.
Z ¹ is selected from the group consisting of a linear or branched alkylene group having 1 to 12 carbon atoms, a linear or branched alkenylene group having 1 to 12 carbon atoms, and an arylene group having 6 to 14 carbon atoms. Is one of the
Part or all of the hydrogen contained in the alkylene group, alkenylene group and arylene group may be substituted with a fluorine atom.
At least one methylene group in the alkylene group, alkenylene group and arylene group may be substituted with a divalent heteroatom-containing group. ) A step of applying the composition according to any one of claims 4 to 8 onto a substrate to form a resist film, and
The step of irradiating the resist film with the first active energy ray and
The step of irradiating the resist film after the irradiation with the first active energy ray with the second active energy ray, and
A method for manufacturing a device, which comprises a step of developing a resist film after irradiation with the second active energy ray to obtain a pattern. The method for manufacturing a device according to claim 9, wherein the wavelength of the first active energy ray is shorter than the wavelength of the second active energy ray. The method for manufacturing a device according to claim 9 or 10, wherein the first active energy ray is an electron beam or extreme ultraviolet rays. The invention according to any one of claims 9 to 11, further comprising a step of heating with a heating wire or a laser between the step of irradiating the first active energy ray and the step of irradiating the second active energy ray. Device manufacturing method. The first active species is generated from the composition in the resist film by the first active energy ray irradiation.
The photoacid generator is structurally changed by the first active species.
The method for manufacturing a device according to any one of claims 9 to 12, wherein a second active species is generated from the structurally changed photoacid generator by the second active energy ray irradiation. The method for manufacturing a device according to claim 13, wherein the structurally changed photoacid generator is a ketone derivative.