JP2018193305A - Iodonium salt compound, photoacid generator and composition containing the same, and method for manufacturing device - Google Patents

Abstract

To provide an iodonium salt compound which can be used as a chemical amplification type photoacid generator for resist and a photocationic polymerization initiator, has high sensitivity to an i-line at a wavelength of 365 nm, and has high solubility to an organic solvent and a resin.SOLUTION: A new iodonium salt compound is represented by the following iodonium salts 2, 5 and 10.SELECTED DRAWING: Figure 1

Description

  One embodiment of the present invention relates to an iodonium salt compound. Another embodiment of the present invention relates to a photoacid generator containing the iodonium salt compound, a composition containing the photoacid generator, and a method for producing a device using the composition.

  In recent years, manufacturing of display devices such as liquid crystal displays and organic EL displays and formation of semiconductor elements have been actively performed by making full use of photolithography technology using a photoresist. A photolithographic technique for forming a fine pattern of the electronic component or the package of the electronic product is used.

  In photolithography technology, i-line having a wavelength of 365 nm is currently widely used as exposure light. The reason why i-line is widely used at present is that an inexpensive medium-pressure / high-pressure mercury lamp showing good emission intensity can be used as an irradiation light source, and an LED lamp having an emission wavelength in the i-line region (360 nm to 390 nm). Has been spreading in recent years. Therefore, among photoacid generators added to the photoresist composition for patterning by controlling the solubility of the resist composition in the developer by deprotection or crosslinking by the action of acid, high sensitivity to i-line It is considered that the need for photoacid generators exhibiting this will increase further in the future. Furthermore, it is considered that the need for a photoacid generator exhibiting high sensitivity to i-line will further increase in the future in a photoacid generator added to a resin composition that is cationically polymerized by the action of an acid.

  Further, i-line lithography for semiconductors such as packaging applications is often used in a thick film for the formation of plated objects such as bumps and metal posts by a plating process. Therefore, it is preferable that the photoacid generator is highly sensitive while ensuring high solubility in a resist solvent.

  The plated model formed in the above plating process is stable in the shape of the plated model, and has improved device reliability such as improved adhesion to the filling material and reduced risk of voids in the subsequent lamination process such as filling and application of the insulating material. Since the improvement can be expected, the width of the bottom (the side in contact with the substrate surface) is desired to be the same as the width of the top facing the bottom or larger than the width of the top. An acid generator that generates an acid by heating has been proposed (Patent Document 1).

  Among existing photoacid generators, sulfonium salts having a (4-benzoylphenylsulfanyl) phenyl skeleton and [2-methoxy-4- (4-methoxybenzoyl) -phenyl] -diphenylsulfonium salt ([2- A sulfonium salt having a diaryl ketone structure such as Methoxy-4- (4-methoxy-benzoyl) -phenyl] -diphenyl-sulfonium) has absorption in the i-line region. Moreover, these sulfonium salts are difficult to produce polyvalent cations and have improved solvent solubility, and are used for thick films for i-line lithography (Patent Documents 2 to 5).

JP, 2006-177018, A JP-A-8-27208 Japanese Patent Laid-Open No. 10-287463 JP2011-195499A WO2007-046442

However, the compounds disclosed in Patent Documents 1 to 5 have a problem that the i-line (365 nm) region is not sufficiently absorbed and the sensitivity is low.
In view of such circumstances, some aspects of the present invention provide an iodonium salt compound as a photoacid generator having high absorption in the i-line region. Further, some embodiments of the present invention provide a photoacid generator containing the iodonium salt compound, a composition containing the photoacid generator, and a method for producing a device using the composition. Let it be an issue.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that iodonium salt compounds having a specific benzoylphenyl structure have i-line absorption compared to sulfonium salts having the same structure as shown above. The present inventors have found that acid is generated with high sensitivity and high sensitivity, and the present invention has been completed.

  One embodiment of the present invention for solving the above problems is an iodonium salt compound represented by the following general formula (1) or the following general formula (2).

In the above formula (1), R ¹ represents any one selected from the group consisting of an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, and an arylsulfanyl group. . R ¹ preferably has 1 to 12 carbon atoms, and these may have a substituent.

R ² , R ³ and R ⁵ are each independently an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, Alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, hydroxy (poly) alkyleneoxy group, amino group, cyano group, nitro group and halogen atom Any one selected from the group consisting of In the case where R ² , R ³ and R ⁵ are groups having a carbon atom, the number of carbon atoms is 1 to 12, and these may have a substituent.

R ⁴ represents one selected from the group consisting of an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, and an arylsulfanyl group.
When R ^{1 to} R ⁵ have a methylene group, at least one of the methylene groups may be substituted with a divalent hetero atom-containing group.

m and n are each independently an integer of 1 to 2.
When m is 1, a is an integer of 1 to 5, b is an integer of 0 to 4, and a + b is an integer of 1 to 5. When m is 2, a is an integer of 1 to 7, b is an integer of 0 to 6, and a + b is an integer of 1 to 7.
When n is 1, d is an integer of 0-4. When n is 2, d is an integer of 0-6.
c is an integer of 0-4.

X ^- represents a counter anion of a monovalent.

In the general formula ^{(2), R 1 ~R 5} , X -, c and m, the ^R 1 ^{to R} 5 in the formula (1), X ^-, is selected from the same options with each of c and m.
m is an integer of 1 to 2, and when m is 1, e is an integer of 1 to 5, f is an integer of 0 to 4, and e + f is an integer of 1 to 5. When m is 2, e is an integer of 1 to 7, f is an integer of 0 to 6, and e + f is an integer of 1 to 7.
g is an integer of 0 to 2, and h is an integer of 0 to 4.

Another embodiment of the present invention is a photoacid generator containing the iodonium salt compound.
Moreover, the other aspect of this invention is a composition containing the said photo-acid generator and an acid-reactive compound.
In another aspect of the present invention, a pattern is obtained by applying the composition onto a substrate to form a resist film, irradiating the resist film with active energy rays, and developing the resist film. And a device manufacturing method including the steps.

  According to some embodiments of the present invention, an iodonium salt compound having high i-line absorption can be provided. In addition, according to some embodiments of the present invention, an iodonium salt compound that is highly soluble in an organic solvent, a resin, or the like used as a component of the resist composition can be provided. The iodonium salt compound can be suitably used as a photoacid generator such as a chemically amplified resist composition using i-line as an active energy ray and a polymerization initiator of a photocationic polymerization composition.

FIG. 1 shows UV spectra of onium salt compounds used in Examples and Comparative Examples.

Hereinafter, although some aspects of the present invention are described concretely, the present invention is not limited to this.
<1> Iodonium salt compound The iodonium salt compound which concerns on one aspect of this invention is an iodonium salt compound represented by the said General formula (1) or the said General formula (2).

The iodonium salt compound according to one embodiment of the present invention has a diaryl ketone skeleton and a specific substituent at the para position of the aryl structure to which the carbonyl group is bonded to the carbonyl group. That is, it has a specific substituent as R < ⁴ > of the said General formula (1) or the said General formula (2). It is preferable to have an electron donating group as the substituent. By having the above structure, the iodonium salt compound has a structure having a large absorption up to the i-line region, and functions as a photoacid generator having high sensitivity to i-line.
Examples of the electron donating group include an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, and an arylsulfanyl group.
Further, as a substituent other than R ⁴ , specifically, it is preferable to further have a substituent such as an alkyl group as at least one of R ^{1 to} R ³ and R ⁵ . When an iodonium salt compound having an alkyl group or the like as at least one of R ^{1 to} R ³ and R ⁵ is used for a resist composition, it is good for organic solvents and resins generally used as components of the resist composition It will have a good solubility. Therefore, the iodonium salt compound having an alkyl group can be used for applications requiring high solubility such as thick film resists.

In the above formula (1), R ¹ is any one selected from the group consisting of an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, an arylsulfanyl group, and the like. Represent. R ¹ is substituent (hereinafter, a substituent R ¹ has also referred to as "first substituent") may have.
From the viewpoint of easy availability of raw materials, the number of carbon atoms of R ¹ is preferably 1 to 12, and more preferably 1 to 6. This carbon number is the number of carbon atoms including the substituent when R ¹ has the first substituent. However, when the first substituent includes a polymer, the number of carbon atoms in the polymer main chain is excluded.

When R ¹ has an alkyl group, specific examples of the alkyl group include linear alkyl groups such as a methyl group, an ethyl group, an n-propyl group, and an n-butyl group;
Branched alkyl groups such as isopropyl and t-butyl groups;
And cyclic alkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, adamantyl group and norbornyl group;

Preferred examples of the alkyl group for R ¹ also include an alkenyl group or an alkynyl group in which at least one carbon-carbon single bond in the alkyl group is substituted with a carbon-carbon double bond or a carbon-carbon triple bond.
In the alkyl group of R ¹ , —O—, —CO—, —COO—, —OCO—, —O—CO—O—, —NHCO—, —CONH—, —NH are substituted for at least one methylene group. Selected from the group consisting of —CO—O—, —O—CO—NH—, —NH—, —N (R) —, —N (Ar) —, —S—, —SO— and —SO ₂ —. One kind of divalent heteroatom-containing group may be included in the skeleton. R and Ar in the divalent heteroatom-containing group will be described later.

Specific examples of the alkoxy group and alkylsulfanyl group in R ¹ include those in which one of —O— bond and —S— bond is substituted with the above alkyl group.

When R ¹ has an aryl group, the aryl group specifically includes a monocyclic aromatic hydrocarbon group such as a phenyl group;
Condensed polycyclic aromatic hydrocarbon groups such as naphthyl group, anthryl group, phenanthrenyl group, pentarenyl group, indenyl group, indacenyl group, acenaphthyl group, fluorenyl group, heptaenyl group, naphthacenyl group, pyrenyl group and chrysenyl group;
Linked polycyclic aromatic hydrocarbon groups such as biphenyl, terphenyl and quaterphenyl groups;
Furanyl, thienyl, pyranyl, sulfanylpyranyl, pyrrolyl, imidazolyl, oxazolyl, thiazolyl, pyrazolyl, and pyridyl, isobenzofuranyl, benzofuranyl, isochromenyl, chromenyl, indolyl And an aromatic heterocyclic group in which the above aromatic hydrocarbon group such as an isoindolyl group, a benzimidazolyl group, a xanthenyl group, an acridinyl group, and a carbazolyl group becomes a heterocyclic ring.

Examples of the first substituent include a hydroxy group, a cyano group, a mercapto group, a carboxy group, an alkoxy group (—OR ⁶ ), an acyl group (—COR ⁶ ), an alkoxycarbonyl group (—COOR ⁶ ), an aryl group (—Ar ¹ ), aryloxy group (—OAr ¹ ), amino group, alkylamino group (—NHR ⁶ ), dialkylamino group (—N (R ⁶ ) ₂ ), arylamino group (—NHAr ¹ ), diarylamino group ( _{^{-N (Ar 1) 2),}} N- alkyl -N- arylamino group ^(-NR 6 ^Ar 1), a phosphino group, a silyl group, a halogen atom, a trialkylsilyl group _{^{(-Si- (R 6) 3)}} , at least one silyl group substituted with Ar ¹ alkyl group of the trialkylsilyl group, an alkylsulfanyl group (-SR ⁶⁾ and Arirusurufu It can be exemplified sulfonyl groups (-SAr ¹⁾ or the like, but are not limited to these.

R ⁶ of the first substituent represents an alkyl group having 1 to 12 carbon atoms, and Ar ¹ represents an aryl group having 6 to 12 carbon atoms. The alkyl group of R ⁶ can be selected from the same as the alkyl group of R ¹ . The aryl group for R ⁶ can be selected from those similar to the aryl group for R ¹ .
Here, also for the R and Ar in the above divalent heteroatom-containing group, each may be selected from the same as the aryl group of the alkyl group and R ¹ in R ^1.
A composition in which the iodonium salt compound includes an iodonium salt compound having a hydroxy group, a mercapto group, an alkylsulfanyl group (—SR ⁶ ), an arylsulfanyl group, a cyano group, or the like as a first substituent is silicon such as silicon or glass. When used in a method for manufacturing an atom-containing substrate or a device having a step of forming a resist film by applying it to a metal substrate having catalytic activity, the iodonium salt compound according to one embodiment of the present invention and the substrate By the action and catalytic reaction, the alkali solubility in the photosensitive resin layer can be changed according to the distance from the substrate by the acid generated from the acid generator.
Moreover, you may have polymeric groups, such as a (meth) acryloyl group, as a 1st substituent.

R ² , R ³ and R ⁵ are each independently an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, Alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, hydroxy (poly) alkyleneoxy group, amino group, cyano group, nitro group and halogen atom Any one selected from the group consisting of, etc.
When R ² , R ³ and R ⁵ have carbon atoms, the number of carbon atoms is preferably 1 to 12, and these are substituents (hereinafter referred to as substituents which R ² , R ³ and R ⁵ have) May also be referred to as a “second substituent”.

When R ² , R ³ and R ⁵ are an alkyl group or a group having an alkyl group, the alkyl group can be specifically selected from those similar to the alkyl group of R ¹ .
When R ² , R ³ and R ⁵ are an aryl group or a group having an aryl group, the aryl group can be specifically selected from those similar to the aryl group of R ¹ .
Incidentally, R ^2, R ³ and any one of the hydroxy groups of R ^5, a mercapto group, an alkylsulfanyl group (-SR ^6), is preferably a polar group such as an arylsulfanyl group and cyano group. A process for producing a device comprising a step of applying a composition containing an iodonium salt compound having these substituents onto a silicon atom-containing substrate such as silicon or glass, or a metal substrate having catalytic activity to form a resist film When used in the above, the alkali solubility in the photosensitive resin layer is set to a distance from the substrate by the acid generated from the acid generator due to the interaction or catalytic reaction between the iodonium salt compound and the substrate of one embodiment of the present invention. It can be changed accordingly.

  The second substituent can be selected from the same as the first substituent.

R ⁴ represents one selected from the group consisting of an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, and an arylsulfanyl group. R ⁴ is a substituent (hereinafter, a substituent R ⁴ have referred to as "third substituent") may have.

When R ⁴ is an alkyl group or a group having an alkyl group, the alkyl group can be specifically selected from those similar to the alkyl group of R ¹ .
When R ⁴ is an aryl group or a group having an aryl group, the aryl group can be specifically selected from those similar to the aryl group of R ¹ .
The third substituent can be selected from the same as the first substituent.

m and n are each independently an integer of 1 to 2.
When m is 1, a is an integer of 1 to 5, b is an integer of 0 to 4, and a + b is an integer of 1 to 5.
When m is 2, a is an integer of 1 to 7, b is an integer of 0 to 6, and a + b is an integer of 1 to 7.
When n is 1, d is an integer from 0 to 4, and when n is 2, d is an integer from 0 to 6.
c is an integer of 0-4.
X ^- represents a counter anion of a monovalent. In the formula (2), R ^{1 to} R ⁵ , X ⁻ , c and m are selected from the same options as each of R ^{1 to} R ⁵ , X ⁻ , c and m in the formula (1).
m is an integer of 1 to 2, and when m is 1, e is an integer of 1 to 5, f is an integer of 0 to 4, e + f is an integer of 1 to 5, and m is 2. When e is an integer of 1 to 7, f is an integer of 0 to 6, and e + f is an integer of 1 to 7.
g is an integer of 0 to 2, and h is an integer of 0 to 4.

  Examples of the iodonium salt compound in some embodiments of the present invention include those having the following iodonium cation. However, the present invention is not limited to this.

X ⁻ is an anion. The anion is not particularly limited, and examples thereof include anions such as sulfonate anion, carboxylate anion, imide anion, methide anion, carboanion, borate anion, halogen anion, phosphate anion, antimonate anion, and arsenate anion.

More specifically, the anion is represented by ZA _i ⁻ , R ¹⁰ _j BA _(4-j) ⁻ , R ¹¹ SO ₃ ⁻ , (R ¹¹ SO ₂ ) ₃ C ⁻ or (R ¹¹ SO ₂ ) ₂ N ^−. Preferred anions are mentioned. Two of R ¹⁰ and two of R ¹¹ 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 (a fluorine atom is preferred).
P represents a phosphorus atom, F represents a fluorine atom, B represents a boron atom, S represents a sulfur atom, O represents an oxygen atom, C represents a carbon atom, and N represents a nitrogen atom.

R ¹⁰ represents a phenyl group in which a part of hydrogen atoms is substituted with at least one halogen atom or electron withdrawing group. Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom. Examples of the electron withdrawing group include a trifluoromethyl group, a nitro group, and a cyano group. Of these, a phenyl group in which one hydrogen atom is substituted with a fluorine atom or a trifluoromethyl group is preferable. The c R ^{10 s} are independent of each other, and thus may be the same as or different from each other.

R ¹¹ represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms in which part or all of the hydrogen atoms may be substituted with fluorine atoms, and the alkyl group is a straight chain or branched chain The aryl group may be unsubstituted or may have a substituent.
i represents an integer of 4-6. j represents an integer of 1 to 4, and is preferably 4.
The anion represented _{^{by, SbF 6 - - ZA i,}} PF 6 - and BF ₄ ^- anion such as represented and the like.

Examples of the anion represented by R ¹⁰ _j BA _(4-j) ⁻ include (C ₆ F ₅ ) ₄ B ⁻ , ((CF ₃ ) ₂ C ₆ H ₃ ) ₄ B ⁻ , and (CF ₃ C ₆ H ₄ ) ₄ B ⁻ , (C ₆ F ₅ ) ₂ BF ₂ ⁻ , C ₆ F ₅ BF ₃ ^— and an anion represented by (C ₆ H ₃ F ₂ ) ₄ B ^— and the like. Of _{these, (C 6 F 5) 4} B - , and _{((CF 3) 2 C 6} H 3) 4 B - anion represented by are preferred.

Examples of the anion represented by R ¹¹ SO ₃ ^— include trifluoromethane sulfonate anion, pentafluoroethane sulfonate anion, heptafluoropropane sulfonate anion, nonafluorobutane sulfonate anion, pentafluorophenyl sulfonate anion, p-toluene. Examples include a sulfonate anion, a benzenesulfonate anion, a camphorsulfonate anion, a methanesulfonate anion, an ethanesulfonate anion, a propanesulfonate anion, and a butanesulfonate anion. Of these, trifluoromethanesulfonate anion, nonafluorobutanesulfonate anion, methanesulfonate anion, butanesulfonate anion, benzenesulfonate anion and p-toluenesulfonate anion are preferred.

Examples of the anion represented by (R ¹¹ SO ₂ ) ₃ C ⁻ include (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.

Examples of the anion represented by (R ¹¹ SO ₂ ) ₂ N ⁻ include (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 - anion, and the like represented. Further, two annular ^{imide (R} 11 SO ₂₎ corresponding portion is bonded to form a ring structure also _{^{(R 11 SO 2) 2 N}} - and the like as the anion represented by.

Examples of the monovalent anion include perhalogenate ions (ClO ₄ ⁻ , BrO ₄ ^— etc.), halogenated sulfonate ions (FSO ₃ ⁻ , ClSO ₃ ⁻ etc.), sulfate ions (CH ₃ SO ₄ ), etc. ^{_{-, 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. ), arylboronic acid ions ^{_{(B (C 6 H 5)}} 4 -, CH 3 CH 2 CH 2 CH 2 B (C 6 H 5) 3 - , etc.), thiocyanate ion (SCN ^- ) And nitrate ions (NO ₃ ⁻ ) can be used.

These anions may have a substituent (hereinafter, the substituent of the anion is also referred to as “fourth substituent”). As the fourth 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, an arylsulfanyl group, an alkylsulfanyl 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 group, nitro group And a halogen atom. 1-12 are preferable and, as for the number of carbon atoms in case the said 4th substituent has a carbon atom, 1-6 are more preferable.
Of these anions, sulfonate anions and carboxylate anions are preferred.

<2> Method for Synthesizing Iodonium Salt Compound The method for synthesizing the iodonium salt compound in one embodiment of the present invention will be described. The present invention is not limited to this.

First, an iodobenzoic acid derivative optionally having an R ³ group is reacted with oxalyl chloride to obtain a corresponding iodobenzoyl chloride derivative. Next, a benzene or naphthalene derivative having an R ⁴ group and optionally an R ⁵ group is introduced into the iodobenzoyl chloride derivative by Friedel-Crafts reaction to obtain an iodobenzophenone derivative or an iodonaphthophenone derivative. Then, after oxidizing an iodine atom with an oxidizing agent, an aromatic compound having an R ¹ group and optionally an R ² group is introduced by an aromatic electrophilic substitution reaction to obtain an iodonium salt precursor. Furthermore, the target iodonium salt compound is obtained by performing salt exchange with respect to the said iodonium salt precursor using the salt which has a corresponding anion.

<3> Photoacid generator One aspect of the present invention is a photoacid generator containing the iodonium salt compound.
The photoacid generator can contain the iodonium salt compound alone or in combination.

<4> Composition One aspect of the present invention is a composition containing the photoacid generator and an acid-reactive compound.

(Photoacid generator)
The content of the photoacid generator in the composition of one embodiment of the present invention is the composition component excluding the photoacid generator (hereinafter, the composition component excluding the photoacid generator is referred to as “basic composition component”). It is preferably 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass, and further preferably 3 to 15 parts by mass with respect to 100 parts by mass.
In the calculation of the content of the photoacid generator, the organic solvent is not included in the basic composition component.

Other photoacid generators (hereinafter also referred to as “second photoacid generators”) other than the photoacid generator (hereinafter also referred to as “first photoacid generator”) containing the iodonium salt compound, General-purpose ionic photoacid generators and nonionic photoacid generators can be mentioned. Examples of the ionic photoacid generator include onium salt compounds such as iodonium salt compounds and sulfonium salt compounds other than those described above. Examples of nonionic photoacid generators include N-sulfonyloxyimide compounds, oxime sulfonate compounds, organic halogen compounds, and sulfonyldiazomethane compounds.
When the second photoacid generator other than the first photoacid generator is included, the content is 0.1 to 50 parts by mass with respect to 100 parts by mass of the basic composition component excluding the total amount of the photoacid generator. Is preferred.

(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 crosslinking agent having a crosslinking action by an acid. Preferably there is.

  The compound having a protecting group that is deprotected by an acid is a compound that generates a polar group by deprotecting the protecting group with an acid and changes the solubility in a developer. For example, in the case of aqueous development using an alkali developer or the like, it is insoluble in an alkali developer, but is exposed to the photoacid generator (the first photoacid generator and / or the second photoacid generator) upon exposure. It is a compound that becomes soluble in an alkaline developer when the protecting group is deprotected from the compound in the exposed area by the acid generated.

  In some embodiments of the present invention, the developer is not limited to an alkaline developer, and may be an aqueous neutral developer or an organic solvent developer. Therefore, when an organic solvent developer is used, a compound having a protecting group that is deprotected with an acid is polarized by deprotecting the protecting group from the compound in the exposed area by an acid generated from the photoacid generator upon exposure. It is a compound that generates a group and has a reduced solubility in an organic solvent developer.

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 that forms a tertiary alkyl ester group with a carboxy group; an alkoxyacetal group; a tetrahydropyranyl group; a siloxy group and a benzyloxy group. As the compound having the protecting group, a compound having a styrene skeleton, novolac skeleton, methacrylate or acrylate skeleton pendant with these protecting groups is preferably used.
The compound having a protecting group to be deprotected with an acid may be a protecting group-containing low molecular weight compound or a unit-containing polymer component having a protecting group.

The compound having a polymerizable group that is polymerized with an acid is a compound that changes the solubility in a developer 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 lowers the solubility of the compound in the aqueous developer after polymerization. Specific examples include compounds having an epoxy group, a vinyloxy group, an oxetanyl group, and the like.
The compound having a polymerizable group that is polymerized with an acid may be a polymerizable low-molecular compound or a unit-containing polymer component having a polymerizable group.

A crosslinking agent having a crosslinking action with an acid is a compound that changes the solubility in a developer by crosslinking with an acid. For example, in the case of aqueous development, it acts on a compound that is soluble in an aqueous developer, and lowers the solubility of the compound in the aqueous developer after polymerization or crosslinking. Specific examples include a crosslinking agent having a crosslinkable 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 cross-linking partner compound, that is, a compound that reacts with the cross-linking agent and changes its solubility in a developing solution include compounds having a phenolic hydroxyl group.
The compound having a crosslinking action with an acid may be a crosslinkable low molecular compound or a unit-containing polymer component having a crosslinkable group.

  When the acid-reactive compound is a polymer component, in addition to the unit containing the deprotecting group, another unit usually used in the resist composition may be contained in the polymer component. Examples of the other unit include a unit having at least one skeleton selected from the group consisting of a lactone skeleton, a sultone skeleton, and a lactam skeleton; and at least selected from the group consisting of an ether bond, an ester bond, an acetal bond, and the like. A unit containing a group having any bond; a hydroxyalkyl group or a hydroxyaryl group-containing unit; and the like. Furthermore, you may contain the said photo-acid generator as a unit.

  When the acid-reactive compound is contained as a unit of the same polymer, the unit that acts as the acid-reactive compound is preferably 5 to 60 mol%, and preferably 10 to 50 mol% in all the units of the polymer. Is more preferable.

(Other ingredients)
In the composition of one embodiment of the present invention, in addition to the above components, as an optional component, an acid diffusion controller, a surfactant, an organic carboxylic acid, an organic solvent, and a dissolution inhibitor that are further used as an optional component in a normal resist composition , Stabilizers and pigments, polymers other than those mentioned above, sensitizers and the like may be included in combination.

  The acid diffusion control agent controls the diffusion phenomenon of the acid generated from the photoacid generator in the resist film, and has an effect of controlling an undesirable chemical reaction in the non-exposed region. Therefore, the storage stability of the resulting resist composition is further improved, the resolution as a resist is further improved, and changes in the line width of the resist pattern due to fluctuations in the holding time from exposure to development processing can be suppressed. Thus, a resist composition having excellent process stability can be obtained.

  Examples of the acid diffusion controller include a compound having one nitrogen atom in the same molecule, a compound having two nitrogen atoms in the same molecule, a compound having three nitrogen atoms in the same molecule, an amide group-containing compound, Examples include urea compounds and nitrogen-containing heterocyclic compounds. Further, as the acid diffusion controlling agent, a photodegradable base that is sensitized by exposure to generate a weak acid can also be used. Examples of the photodegradable base include an onium salt compound that decomposes upon exposure and loses acid diffusion controllability.

  Specific examples of the acid diffusion control agent include Japanese Patent No. 3577743, Japanese Patent Application Laid-Open No. 2001-215589, Japanese Patent Application Laid-Open No. 2001-166476, Japanese Patent Application Laid-Open No. 2008-102383, Japanese Patent Application Laid-Open No. 2010-243773, Japanese Patent Application Laid-Open No. 2011-37835, Examples thereof include compounds described in Kai 2012-173505 and the like.

  The content of the acid diffusion controller is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, with respect to 100 parts by mass of the basic composition component, and 0.05 More preferably, it is -3 mass parts.

  The surfactant is preferably used for improving the coating property. Examples of surfactants include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene polyoxypropylene block copolymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, etc. Agents, fluorosurfactants, organosiloxane polymers, and the like.

  The content of the surfactant is preferably 0.0001 to 2 parts by mass and more preferably 0.0005 to 1 part by mass with respect to 100 parts by mass of the basic 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 -Naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, etc. can be mentioned. When performing electron beam exposure under vacuum, since there is a risk of volatilizing from the resist film surface and contaminating the drawing chamber, preferred organic carboxylic acids include aromatic organic carboxylic acids, among which, for example, benzoic acid, 1-hydroxy-2-naphthoic acid and 2-hydroxy-3-naphthoic acid are preferred.

  The content of the organic carboxylic acid is preferably 0.01 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, and still more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the basic composition component. Part.

  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, propylene glycol monoethyl ether. Acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl β-methoxyisobutyrate, ethyl butyrate, propyl butyrate, methyl isobutyl ketone, ethyl acetate, isoamyl acetate, ethyl lactate, toluene, xylene, cyclohexyl acetate, diacetone Alcohol, N-methylpyrrolidone, N, N-dimethylformamide, γ-butyrolactone, N, N-dimethylacetoa Mido, propylene carbonate, ethylene carbonate and the like are preferable. These organic solvents are used alone or in combination.

  The solid component containing the basic composition component and the photoacid generator is preferably dissolved in the organic solvent and dissolved in the composition at a solid content concentration of 1 to 40% by mass. More preferably, it is 1-30 mass%, More preferably, it is 3-20 mass%.

  The sensitizer is not particularly limited as long as the effect of the iodonium salt compound of some aspects of the present invention is not reduced, and examples thereof include thioxanthone derivatives, benzophenone derivatives, naphthalene derivatives, anthracene derivatives, alkyl alcohols, and aryl alcohols. It is done.

  When the composition of one aspect of the present invention includes a polymer, the polymer preferably has a weight average molecular weight of 2000 to 200000, more preferably 2000 to 50000, and still more preferably 2000 to 15000. . The preferable dispersion degree (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 converted values by GPC measurement.

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

<5> Device Manufacturing Method One aspect of the present invention includes a step of forming a resist film by, for example, applying the composition on a substrate, a step of irradiating the resist film with active energy rays, and the activity And developing a resist film after irradiation with energy rays to obtain a pattern.

One embodiment of the present invention includes a step of forming a resist film, a step of irradiating active energy rays and a step of obtaining a pattern using the above composition, and having a pattern before obtaining individualized chips It may be a manufacturing method.
One aspect of the present invention is a device comprising: a step of forming a coating film on a substrate using the composition; and a step of exposing the coating film using an active energy ray to obtain an interlayer insulating film. It may be a manufacturing method.

  The active energy ray is not particularly limited as long as the iodonium salt compound according to some embodiments of the present invention can generate an acid in the resist film after irradiation with the resist film. For example, KrF excimer laser light, UV Visible light or the like is preferable, and it is particularly preferable to use light in the 365 nm (i-line) region of UV light.

The substrate is not particularly limited, and a known substrate can be used. For example, silicon atom-containing substrates such as silicon, silicon nitride, and glass; metal substrates such as titanium, tantalum, palladium, copper, chromium, and aluminum;
In one embodiment of the present invention, UV, KrF excimer laser light, ArF excimer laser light, electron beam, extreme ultraviolet light (EUV), or the like is used as an active energy ray for obtaining an interlayer insulating film or the like for LSI production. Preferably mentioned.

The amount of light irradiation varies depending on the type and blending ratio of each component in the composition, the film thickness of the coating film, etc., but is preferably 1 J / cm ² or less or 1000 μC / cm ² or less.
In one embodiment of the present invention, the thickness of the resist film formed from the composition is preferably 0.1 to 10 μm. The composition is applied onto the substrate by an appropriate application method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, and the like, and is performed at 60 to 150 ° C. for 1 to 20 minutes, preferably 80 to 120. A thin film is formed by prebaking at 10 ° C. for 1 to 10 minutes. The thickness of the coating film is preferably 0.1 to 10 μm.

  Hereinafter, some embodiments of the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

<Synthesis of iodonium salt compound>
Synthesis Example 1 Synthesis of 2-iodobenzoyl chloride

  Dissolve 4.3 g of 2-iodobenzoic acid in 30 g of methylene chloride to 50 ° C. To this, 2.6 g of oxalyl chloride is added dropwise over 10 minutes and stirred at 40 ° C. for 2 hours. By distilling methylene chloride and excess oxalyl chloride at 70 ° C., 4.2 g of 2-iodobenzoyl chloride is obtained.

Synthesis Example 2 Synthesis of 2-iodo-4′-methoxybenzophenone

  Add 3.0 g of aluminum chloride to 28 g of methylene chloride and bring to 0 ° C. After adding 2.0 g of anisole to this, 4.2 g of 2-iodobenzoyl chloride obtained in Synthesis Example 1 is dissolved in 8.4 g of methylene chloride and added dropwise over 30 minutes. After dropping, the mixture is stirred for 1 hour at 25 ° C., 60 g of pure water is added and the mixture is further stirred for 5 minutes, extracted twice with 20 g of methylene chloride, and washed with a 5 mass% aqueous sodium hydroxide solution. This is separated, and the obtained organic layer is concentrated and added dropwise to 60 g of hexane to precipitate a solid. The precipitated solid is separated by filtration, washed twice with 20 g of hexane, and dried to obtain 4.8 g of 2-iodo-4′-methoxybenzophenone.

Synthesis Example 3 Synthesis of 2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  4.7 g of 2-iodo-4′-methoxybenzophenone obtained in Synthesis Example 2 and 5.7 g of acetic anhydride are added to 11 g of acetonitrile to obtain 0 ° C. To this, 5.5 g of sulfuric acid and 1.6 g of 35 mass% hydrogen peroxide water are added dropwise and stirred at 25 ° C. for 1 hour, then 2.0 g of anisole is added dropwise and stirred at 25 ° C. for an additional 2 hours. After cooling, 30 g of pure water and 30 g of diisopropyl ether are added. To the aqueous layer obtained by liquid separation, 4.7 g of potassium perfluorobutanesulfonate and 30 g of methylene chloride are added and stirred at 25 ° C. for 1 hour. The organic layer obtained by liquid separation is washed twice with 30 g of a 3% by mass aqueous sodium hydrogen carbonate solution and twice with 30 g of pure water, and then the organic layer is dropped into 50 g of diisopropyl ether to precipitate a solid. The precipitated solid was separated by filtration, washed twice with 20 g of diisopropyl ether, and then dried to obtain 8.7 g of 2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate.

Synthesis Example 4 Synthesis of 2- (4-methoxybenzoyl) phenyl-2 ′, 4′-dimethoxyphenyliodonium-perfluorobutanesulfonate

  2- (4-methoxybenzoyl) phenyl-2 ′, 4′-dimethoxyphenyliodonium-perfluorobutane is obtained by performing the same operation as in Synthesis Example 3 except that 1,3-dimethoxybenzene is used instead of anisole. 9.1 g of sulfonate are obtained.

Synthesis Example 5 Synthesis of 2- (4-methoxybenzoyl) phenyl-2 ′, 4 ′, 6′-trimethylphenyliodonium-perfluorobutanesulfonate

  2- (4-Methoxybenzoyl) phenyl-2 ′, 4 ′, 6′-trimethylphenyliodonium-perfluorobutanesulfonate 8 by performing the same operation as in Synthesis Example 3 except that mesitylene was used instead of anisole. .8 g is obtained.

Synthesis Example 6 Synthesis of 2- (4-methoxybenzoyl) phenyl-4′-methoxy-3′-methylphenyliodonium-perfluorobutanesulfonate

  2- (4-Methoxybenzoyl) phenyl-4′-methoxy-3′-methylphenyliodonium-perfluorobutane is obtained by performing the same operation as in Synthesis Example 3 except that 2-methoxytoluene is used instead of anisole. 8.3 g of sulfonate are obtained.

Synthesis Example 7 Synthesis of 2- (4-methoxybenzoyl) phenyl-3′-cyanomethyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  2- (4-methoxybenzoyl) phenyl-3′-cyanomethyl-4′-methoxyphenyliodonium-perfluoro was obtained by performing the same operation as in Synthesis Example 3 except that 2-methoxyphenylacetonitrile was used instead of anisole. 8.9 g of butanesulfonate are obtained.

Synthesis Example 8 Synthesis of 2- (4-methoxybenzoyl) phenyl-3′-acetonyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  2- (4-Methoxybenzoyl) phenyl-3′-acetonyl-4′-methoxyphenyliodonium-perfluoro was obtained by performing the same operation as in Synthesis Example 3 except that 2-methoxyphenylacetone was used instead of anisole. 9.1 g of butane sulfonate are obtained.

Synthesis Example 9 Synthesis of diethylene glycol methyl phenyl ether

  2.7 g of diethylene glycol monophenyl ether is added to 14 g of N, N-dimethylformamide, 0.54 g of sodium hydride and 3.2 g of iodomethane are added under ice cooling, and the mixture is stirred at room temperature for 5 hours. Thereafter, 20 g of pure water and 20 g of methylene chloride were added, and the resulting organic layer was separated and washed three times with 20 g of pure water. After concentration, silica gel column chromatography (developing solvent: n-hexane / ethyl acetate) = 2/1), 2.4 g of diethylene glycol methyl phenyl ether is obtained.

Synthesis Example 10 2- (4-Methoxybenzoyl) phenyl-4 ′-[2- (2-methoxyethoxy) ethoxy] phenyliodonium-perfluorobutanesulfonate

  2- (4-Methoxybenzoyl) phenyl-4 ′-[2- (2-methoxyethoxy) ethoxy] phenyl was obtained by performing the same operation as in Synthesis Example 3 except that diethylene glycol methylphenyl ether was used instead of anisole. 9.8 g of iodonium-perfluorobutane sulfonate are obtained.

(Synthesis Example 11) Synthesis of 4-phenyloxybutyronitrile

  Add 3.4 g of phenol, 6.2 g of potassium carbonate and 3.1 g of 4-chlorobutyronitrile to 33 g of dimethyl sulfoxide and stir at 70 ° C. for 8 hours. Thereafter, 30 g of pure water, 30 g of n-hexane and 30 g of ethyl acetate were added, and the resulting organic layer was separated and washed once with 40 g of 5 mass% aqueous sodium hydroxide and 50 g of pure water, By distilling off the solvent, 3.3 g of 4-phenyloxybutyronitrile is obtained.

Synthesis Example 12 Synthesis of 2- (4-methoxybenzoyl) phenyl-4 ′-(3-cyanopropoxy) phenyliodonium-perfluorobutanesulfonate

  2- (4-Methoxybenzoyl) phenyl-4 ′-(3-cyanopropoxy) phenyliodonium- was prepared in the same manner as in Synthesis Example 3 except that 4-phenyloxybutyronitrile was used instead of anisole. 9.1 g of perfluorobutane sulfonate are obtained.

Synthesis Example 13 Synthesis of phenyloxyacetonitrile

  2.7 g of phenyloxyacetonitrile is obtained by performing the same operation as in Synthesis Example 11 except that chloroacetonitrile is used instead of 4-chlorobutyronitrile.

Synthesis Example 14 Synthesis of 2- (4-methoxybenzoyl) phenyl-4 ′-(cyanomethoxy) phenyliodonium-perfluorobutanesulfonate

  Except for using phenyloxyacetonitrile in place of anisole, the same procedure as in Synthesis Example 3 was performed to obtain 2- (4-methoxybenzoyl) phenyl-4 ′-(cyanomethoxy) phenyliodonium-perfluorobutanesulfonate 8 .8 g is obtained.

Synthesis Example 15 Synthesis of 2-iodo-4′-methoxy-α-naphthophenone

  The same procedure as in Synthesis Example 2 is performed except that 1-methoxynaphthalene is used in place of anisole to obtain 5.5 of 2-iodo-4′-methoxy-α-naphthophenone.

Synthesis Example 16 Synthesis of 2- (4-methoxy-α-naphthoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  The same procedure as in Synthesis Example 3 was performed except that 2-iodo-4′-methoxy-α-naphthophenone was used instead of 2-iodo-4′-methoxybenzophenone, whereby 2- (4-methoxy-α- 9.3 g of naphthoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate are obtained.

Synthesis Example 17 Synthesis of 2-fluoro-6-iodobenzoyl chloride

  4.5 g of 2-fluoro-6-iodobenzoyl chloride is obtained by performing the same operation as in Synthesis Example 1 except that 2-fluoro-6-iodobenzoic acid is used instead of 2-iodobenzoic acid.

Synthesis Example 18 Synthesis of 2-fluoro-6-iodo-4′-methoxybenzophenone

  2-Fluoro-6-iodo-4′-methoxybenzophenone is obtained in the same manner as in Synthesis Example 2 except that 2-fluoro-6-iodobenzoyl chloride is used instead of 2-iodobenzoyl chloride. 1 g is obtained.

Synthesis Example 19 Synthesis of 3-fluoro-2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  3-Fluoro-2- (4) is obtained by performing the same operation as in Synthesis Example 3 except that 2-fluoro-6-iodo-4′-methoxybenzophenone is used instead of 2-iodo-4′-methoxybenzophenone. 8.9 g of -methoxybenzoyl) phenyl-4'-methoxyphenyliodonium-perfluorobutanesulfonate.

Synthesis Example 20 Synthesis of 4-n-butoxy-2′-iodobenzophenone

  Synthetic Example 2 except that n-butylphenyl ether is used instead of anisole, and purification is performed by silica gel column chromatography (developing solvent: n-hexane / ethyl acetate = 9/1) instead of crystallization purification using diisopropyl ether. 5.4 g of 4-n-butoxy-2′-iodobenzophenone is obtained by performing the same operation as above.

Synthesis Example 21 Synthesis of 2- (4-n-butoxybenzoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  2- (4-n-butoxybenzoyl) was obtained by performing the same operation as in Synthesis Example 3 except that 4-n-butoxy-2′-iodobenzophenone was used instead of 2-iodo-4′-methoxybenzophenone. 9.2 g of phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate are obtained.

Synthesis Example 22 Synthesis of 4-iodobenzoyl chloride

  By performing the same operation as in Synthesis Example 1 except that 4-iodobenzoic acid is used in place of 2-iodobenzoic acid, 4.2 g of 4-iodobenzoyl chloride is obtained.

Synthesis Example 23 Synthesis of 4-iodo-4′-methoxybenzophenone

  4.8 g of 4-iodo-4′-methoxybenzophenone is obtained by performing the same operation as in Synthesis Example 2 except that 4-iodobenzoyl chloride is used in place of 2-iodobenzoyl chloride.

Synthesis Example 24 Synthesis of 4- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate

  4- (4-Methoxybenzoyl) phenyl-4 ′ is obtained by performing the same operation as in Synthesis Example 3 except that 4-iodo-4′-methoxybenzophenone is used instead of 2-iodo-4′-methoxybenzophenone. 8.7 g of methoxyphenyliodonium-perfluorobutanesulfonate are obtained.

Synthesis Example 25 Synthesis of 2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-tetrafluoroborate

  2- (4-Methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-tetrafluoro was obtained by performing the same operation as in Synthesis Example 3 except that sodium tetrafluoroborate was used instead of potassium perfluorobutanesulfonate. 6.2 g borate is obtained.

Synthesis Example 26 Synthesis of 2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-hexafluorophosphate

  2- (4-Methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-hexafluoro was obtained by performing the same operation as in Synthesis Example 3 except that potassium hexafluorophosphate was used instead of potassium perfluorobutanesulfonate. 6.9 g of phosphate are obtained.

Synthesis Example 27 Synthesis of 2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyliodonium-tetrakis (pentafluorophenyl) borate

  2- (4-methoxybenzoyl) phenyl-4′-methoxyphenyl was obtained by performing the same operation as in Synthesis Example 3 except that sodium tetrakis (pentafluorophenyl) borate was used instead of potassium perfluorobutanesulfonate. 13.1 g of iodonium-tetrakis (pentafluorophenyl) borate are obtained.

Comparative Synthesis Example 1 Synthesis of 4-t-butyl-2′-iodobenzophenone

  5.2 g of 4-t-butyl-2′-iodobenzophenone is obtained by performing the same operation as in Synthesis Example 2 except that t-butylbenzene is used instead of anisole.

(Comparative Synthesis Example 2) Synthesis of 2- (4-t-butylbenzoyl) phenyl-4'-methoxyphenyliodonium-perfluorobutanesulfonate

2- (4-t-butylbenzoyl) was obtained by performing the same operation as in Synthesis Example 3 except that 4-t-butyl-2′-iodobenzophenone was used instead of 2-iodo-4′-methoxybenzophenone. 9.0 g of phenyl-4′-methoxyphenyliodonium-perfluorobutanesulfonate are obtained.

<Polymer synthesis>
Synthesis Example 28 Polymer Synthesis 8.0 g of polyhydroxystyrene (weight average molecular weight 8000) and 0.010 g of 35% by mass aqueous hydrochloric acid solution are dissolved in 28 g of dehydrated dioxane. Thereto, 2.34 g of ethyl vinyl ether is dissolved 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. Thereafter, the polymer is precipitated by dropping the solution into 260 g of pure water. The solid obtained by separating this by vacuum filtration was washed twice with 300 g of pure water, and then vacuum-dried to obtain 8.9 g of the polymer shown below as a white solid. In addition, the monomer ratio of the polymer units in some embodiments of the present invention is not limited to the following.

[Examples 1 to 6 and Comparative Examples 1 to 4]
<Molar extinction coefficient measurement>
The chloroform solutions (0.1 mM) of the above iodonium salts 1 to 5 and iodonium salt 8 and the comparative sulfonium salt and comparative iodonium salt 1 to 3 shown below were prepared, and an ultraviolet-visible spectrophotometer (product name: V- The absorbance is measured using 550, JASCO Corporation. The molar extinction coefficient is calculated from the concentration and absorbance of the sample solution.

<Sensitivity evaluation>
Samples 1-10 are prepared as follows. To 3000 mg of cyclohexanone, 500 mg of the polymer, 0.018 mmol of any of the iodonium salts 1 to 5 and iodonium salt 8 as photoacid generators, and the comparative sulfonium salt and comparative iodonium salts 1 to 3 shown below, A sample is prepared using 0.0006 mmol of trioctylamine as a quencher, 0.15 mg of Novac FC-4434 (manufactured by 3M) as a surfactant, and 0.0008 mmol of salicylic acid as an organic carboxylic acid.
Each prepared sample is coated on a Si wafer that has been subjected to hexamethyldisilazane (HMDS) treatment in advance, and each of the evaluation samples 1 to 13 is applied by spin coating and heated at 110 ° C. to obtain a resist film having a thickness of 500 nm. .
Next, the evaluation sample is exposed by changing the exposure amount by a UV exposure apparatus having a bright line of 365 nm through a 1: 1 line having a line width half pitch of 2 μm and a space pattern mask. Subsequently, it heats at 110 degreeC on a hotplate for 1 minute.
After heating, development is performed for 1 minute using a developer (product name: NMD-3, 2.38 mass% tetramethylammonium hydroxide aqueous solution, manufactured by Tokyo Ohka Kogyo Co., Ltd.), and rinsed with pure water. Get the pattern. This is observed with a microscope, and the exposure amount at which the resist is completely peeled is defined as E _size (minimum exposure amount). The results of evaluating the minimum exposure amount as sensitivity are shown in Table 1. As for the sensitivity of each sample, the sensitivity of the sample to which the iodonium salt 1 is added (Example 1) is set as 100, and the evaluation result of each sample is calculated as a relative value.

  Examples 1 to 6, which are samples containing an iodonium salt compound in some aspects of the present invention, have a larger molar extinction coefficient at a wavelength of 365 nm than Comparative Examples 1 to 4. Comparative Example 1 uses a comparative sulfonium salt having a 4-methoxybenzoyl group, Comparative Example 2 uses a comparative iodonium salt 1 having a tertbutyl group at the 4-position of benzoyl, and Comparative Examples 3 and 4 are each via oxygen or Comparative iodonium salts 3 and 4 that are cyclic by direct bonding are used. In Examples 1 to 6, the acid generation efficiency is improved by increasing the i-line absorption efficiency, and the sensitivity is higher than those of Comparative Examples 1 to 4 using the comparative onium salt compound.

That is, the iodonium salt compound according to some embodiments of the present invention has a specific substituent having a higher electron donating property than the alkyl group such as a methoxy group at the 4-position of the benzoyl group, so that 1 × It has an absorption of 10 ⁶ cm ² / mol or more and the sensitivity is greatly improved. In addition, since the iodonium salt compound of some embodiments of the present invention has an absorption of 400 nm or more of 5 × 10 ⁵ cm ² / mol or less, the acid generation efficiency in visible light is remarkably low, and the visible light transmittance is required. It is effective in the case.
In addition, the UV spectrum of the iodonium salt 1-2, the comparative sulfonium salt, and the comparative iodonium salt 1 is shown in FIG.

  According to some embodiments of the present invention, an iodonium salt compound having high sensitivity to i-line can be provided. The iodonium salt compound can be suitably used as a photoacid generator for a chemically amplified resist composition using i-line as an active energy ray, a polymerization initiator for a photocationic polymerization composition, and the like.

Claims (6)

An iodonium salt compound represented by the following formula (1) or (2).


(In the formula (1), R ¹ is any one selected from the group consisting of an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, and an arylsulfanyl group. Which may have a substituent,
R ² , R ³ and R ⁵ are each independently an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanylcarbonyl group, an arylsulfanyl group, Alkylsulfanyl group, aryl group, heteroaryl group, aryloxy group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, hydroxy (poly) alkyleneoxy group, amino group, cyano group, nitro group and halogen atom Any one selected from the group consisting of 1 to 12 carbon atoms when having carbon atoms, and these may have a substituent,
R ⁴ represents any one selected from the group consisting of an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsulfanyl group, and an arylsulfanyl group, and these may have a substituent,
When R ^{1 to} R ⁵ have a methylene group, at least one of the methylene groups may be substituted with a divalent heteroatom-containing group;
m and n are each independently an integer of 1 to 2,
When m is 1, a is an integer of 1 to 5, b is an integer of 0 to 4, a + b is an integer of 1 to 5,
When m is 2, a is an integer of 1-7, b is an integer of 0-6, a + b is an integer of 1-7,
When n is 1, d is an integer of 0 to 4,
When n is 2, d is an integer of 0 to 6,
c is an integer from 0 to 4,
X ^- represents a counter anion of a monovalent.
In the formula (2), R ^{1 to} R ⁵ , X ⁻ , c and m are selected from the same options as each of R ^{1 to} R ⁵ , X ⁻ , c and m in the formula (1),
m is an integer of 1 to 2,
When m is 1, e is an integer of 1 to 5, f is an integer of 0 to 4, e + f is an integer of 1 to 5,
When m is 2, e is an integer of 1 to 7, f is an integer of 0 to 6, e + f is an integer of 1 to 7,
g is an integer of 0-2,
h is an integer of 0-4. ) The iodonium salt compound according to claim 1, wherein the molar extinction coefficient at a wavelength of 365 nm is 1 × 10 ⁶ cm ² / mol or more and the molar extinction coefficient at a wavelength of 400 nm is 5 × 10 ⁵ cm ² / mol or less.   A photoacid generator containing the iodonium salt compound according to claim 1.   A composition comprising the photoacid generator according to claim 3 and an acid-reactive compound.   The composition of claim 4 further comprising a polymer or oligomer having a hydroxyaryl group. Applying the composition according to claim 4 or 5 on a substrate to form a resist film;
Irradiating the resist film with active energy rays;
And developing a resist film after irradiating the active energy rays to form a pattern.