JP6948828B2 - Iodonium salt compounds, photoacid generators and compositions containing them, and methods for manufacturing devices. - Google Patents

Description

One aspect of the present invention relates to an iodonium salt compound. Another aspect 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, the manufacture of display devices such as liquid crystal displays and organic EL displays and the formation of semiconductor elements have been actively carried out by making full use of photolithography technology using photoresists. Photolithography technology for forming fine patterns of the above-mentioned electronic parts and packages of electronic products is used.

In photolithography technology, i-rays with a wavelength of 365 nm are currently widely used as exposure light. The reasons why i-rays are widely used at present are that medium-pressure and high-pressure mercury lamps that are inexpensive but exhibit good emission intensity can be used as irradiation light sources, and LED lamps that have emission wavelengths in the i-line region (360 nm to 390 nm). Is becoming popular in recent years. Therefore, among the photoacid generators added to the photoresist composition for controlling the solubility of the resist composition in a developing solution and patterning by deprotecting or cross-linking by the action of an acid, the sensitivity to i-ray is high. The need for photoacid generators that show the above is expected to increase further in the future. Further, it is considered that the need for a photoacid generator that exhibits high sensitivity to i-rays will further increase in the photoacid generator added to the resin composition that is cationically polymerized by the action of an acid.

In addition, i-line lithography for semiconductors for packaging applications is often used for thick films, for example, for forming plated objects such as bumps and metal posts by a plating process. Therefore, it is preferable that the photoacid generator has high sensitivity while ensuring high solubility in the resist solvent.

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

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

JP-A-2016-177018 Japanese Unexamined Patent Publication No. 8-27208 Japanese Unexamined Patent Publication No. 10-287643 Japanese Unexamined Patent Publication No. 2011-195499 WO2007-046442

However, the compounds disclosed in Patent Documents 1 to 5 have a problem that the absorption in the i-line (365 nm) region is not sufficient and the sensitivity is low.
In view of such circumstances, it is an object of some aspects of the present invention to provide an iodonium salt compound as a photoacid generator having high absorption in the i-ray region. In addition, some aspects 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. Make it an issue.

As a result of diligent studies to solve the above problems, the present inventor has found that an iodonium salt compound having a specific benzoylphenyl structure absorbs i-rays as compared with a sulfonium salt having a similar structure as shown above. We have found that acid is generated with high sensitivity and high sensitivity, and have completed the present invention.

One aspect 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. .. The ^{number of carbon atoms of R 1} is preferably 1 to 12, and these may have substituents.

Each R ^2, R ³ and R ⁵ are independently an alkyl group, hydroxy group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanyl group, arylsulfanyl groups, Alkyl sulfanyl 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 It is one selected from the group consisting of. When 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 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.
When the above 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 independently integers of 1 to 2 respectively.
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. When n is 2, d is an integer from 0 to 6.
c is an integer from 0 to 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 aspect of the present invention is a photoacid generator containing the iodonium salt compound.
Another aspect of the present invention is a composition containing the photoacid generator and an acid-reactive compound.
Further, 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 active energy rays, and a step of developing the resist film to obtain a pattern. A process and a method of manufacturing a device including.

According to some aspects of the present invention, it is possible to provide an iodonium salt compound having high i-ray absorption. Further, according to some aspects of the present invention, it is possible to provide an iodonium salt compound having high solubility in an organic solvent, a resin or the like used as a component of a resist composition. The iodonium salt compound can be suitably used as a photoacid generator such as a chemically amplified resist composition using i-ray as an active energy ray, a polymerization initiator of a photocationic polymerization composition, and the like.

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

Hereinafter, some aspects of the present invention will be specifically described, but the present invention is not limited thereto.
<1> Iodonium salt compound The iodonium salt compound according to one aspect of the present invention is an iodonium salt compound represented by the above general formula (1) or the above general formula (2).

The iodonium salt compound according to one aspect of the present invention has a diarylketone skeleton and has a specific substituent at the para position with respect to the carbonyl group of the aryl structure to which the carbonyl group is bonded. In other words, having a specific substituent as R ⁴ in the general formula (1) or the 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-ray region, and functions as a photoacid generator having high sensitivity to i-rays.
Examples of the electron donating group include an alkoxy group, an aryloxy group, an alkoxyaryl group, an aryloxyaryl group, an alkylsfanyl 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 in the 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 also be used for applications requiring high solubility such as thick film resists.

In the above formula (1), R ¹ is 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. show. R ¹ may have a substituent (hereinafter, the ^{substituent contained in R 1} is also referred to as “first substituent”).
From the viewpoint of 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 contains a polymer, the number of carbon atoms in the polymer main chain shall be excluded.

When R ¹ has an alkyl group, the alkyl group is specifically a linear alkyl group such as a methyl group, an ethyl group, an n-propyl group and an n-butyl group;
Branched alkyl groups such as isopropyl group and t-butyl group;
Cyclic alkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, adamantyl group and norbornyl group; and the like.

As ^{the alkyl group of R 1} , an alkenyl group or an alkynyl group in which at least one carbon-carbon single bond in the alkyl group is replaced with a carbon-carbon double bond or a carbon-carbon triple bond is also preferably mentioned.
In ^{the alkyl group of R 1} , instead of at least one methylene group, -O-, -CO-, -COO-, -OCO-, -O-CO-O-, -NHCO-, -CONH-, -NH Selected from the group consisting of -CO-O-, -O-CO-NH-, -NH-, -N (R)-, -N (Ar)-, -S-, -SO- and -SO _2- The skeleton may contain one type of divalent heteroatom-containing group. R and Ar in the divalent heteroatom-containing group will be described later.

Specific examples of the alkoxy group and the alkylsulfuranyl group in R ¹ include those in which one of the -O- bond and the -S- bond is substituted with the above alkyl group, respectively.

When R ¹ has an aryl group, the aryl group is specifically 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, indasenyl group, acenaphthyl group, fluorenyl group, heptalenyl group, naphthacenyl group, pyrenyl group and chrysenyl group;
Linked polycyclic aromatic hydrocarbon groups such as biphenyl groups, terphenyl groups and quaterphenyl groups;
Furanyl group, thienyl group, pyranyl group, sulfanylpyranyl group, pyrrolyl group, imidazolyl group, oxazolyl group, thiazolyl group, pyrazolyl group, and pyridyl group, isobenzofuranyl group, benzofuranyl group, isochromenyl group, chromenyl group, indolyl group. , An aromatic heterocyclic group in which the above aromatic hydrocarbon group such as an isoindryl group, a benzoimidazolyl group, a xanthenyl group, an acridinyl group and a carbazolyl group is a heterocycle; and the like.

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 ), and 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 (-NHAr 1) -N (Ar ¹ ) ₂ ), N-alkyl-N-arylamino group (-NR ⁶ Ar ¹ ), phosphino group, silyl group, halogen atom, trialkylsilyl group (-Si- (R ⁶ ) ₃ ), Examples thereof include, but are not limited to, a silyl group in which at least one of the alkyl groups of the trialkylsilyl group ^{is substituted with Ar 1 , an alkylsulfanyl group (-SR 6} ), an arylsulfanyl group (-SAR ^{1), and the like.} ..

^{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 of R ⁶ can be selected from the same as the aryl group of ^{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.
The composition containing an iodonium salt compound having 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 made of silicon such as silicon or glass. When used in a method for producing a device having a step of forming a resist film by applying it to an atomic-containing substrate or a metal substrate having catalytic activity, the iodonium salt compound according to one aspect of the present invention and the substrate are mutually used. Depending on the action or catalytic reaction, the acid generated from the acid generator makes it possible to change the alkali solubility in the photosensitive resin layer according to the distance from the substrate.
Further, it may have a polymerizable group such as a (meth) acryloyl group as the first substituent.

Each R ^2, R ³ and R ⁵ are independently an alkyl group, hydroxy group, an alkoxy group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an arylsulfanyl group, arylsulfanyl groups, Alkyl sulfanyl 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 It is one selected from the group consisting of the like.
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, substituents of R ² , R ³ and R ⁵ ). May also have 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 the same as 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 the same as 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 method for producing a device having a step of applying a composition containing an iodonium salt compound having these substituents on 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 acid generated from the acid generator increases the alkali solubility in the photosensitive resin layer to the distance from the substrate due to the interaction or catalytic reaction between the iodonium salt compound of one aspect of the present invention and the substrate. It can be changed accordingly.

The second substituent can be selected from the same as the first 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. R ⁴ may have a substituent (hereinafter, the ^{substituent contained in R 4} is also referred to as a “third substituent”).

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

m and n are independently integers of 1 to 2 respectively.
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 to 4, and 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 those of 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, 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 aspects of the present invention include those having the iodonium cations shown below. 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 sulfonic acid anion, carboxylic acid anion, imide anion, methide anion, carboan anion, borate anion, halogen anion, phosphate anion, antimonic acid anion and arsenic acid anion.

More specifically, the anions are 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 ^−. Anions are preferred. Each of the two is two and R ¹¹ of R ^10, 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, 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 a hydrogen atom is substituted with at least one halogen atom or 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 ¹⁰ is independently from each other, therefore, it may be the same or different from each other.

R ¹¹ 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 straight chain or a branched chain. It may be cyclic or cyclic, and the aryl group may be unsubstituted or having a substituent.
i represents an integer of 4 to 6. j represents an integer of 1 to 4, preferably 4.
Examples of the _{anion represented by ZA i} ⁻ include anions represented by SbF ₆ ⁻ , PF ₆ ⁻ and BF ₄ ⁻ .

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

R ¹¹ 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 ¹¹ 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 ¹¹ 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 11} SO 2) are bonded to each other to form a ring structure is also mentioned as an anion represented by ^{(R 11} 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. ), 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 ion (NO ₃ ^- ) Etc. can be used.

These anions may have a substituent (hereinafter, the substituent contained in the anion is also referred to as a "fourth substituent"). Examples of the fourth substituent include 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, and 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 halogen atoms and the like. When the fourth substituent has a carbon atom, the number of carbon atoms is preferably 1 to 12, and more preferably 1 to 6.
Of these anions, sulfonic acid anions, carboxylic acid anions and the like are preferable.

<2> Method for synthesizing the above-mentioned iodonium salt compound A method for synthesizing an iodonium salt compound in one embodiment of the present invention will be described. The present invention is not limited to this.

First, optionally reacted with oxalyl chloride in iodobenzoic acid derivative having R ³ groups to give the corresponding iodo benzoyl chloride derivative. Then, ^{a benzene or naphthalene derivative having 4} R groups and optionally ⁵ R groups is introduced into the iodobenzoyl chloride derivative by the Friedel-Crafts reaction to obtain an iodobenzophenone derivative or an iodonaphthophenone derivative. Subsequently, after oxidizing the iodine atom with an oxidizing agent ^{, an aromatic compound having R 1} group and optionally R ² group is introduced by an aromatic electrophilic substitution reaction to obtain an iodonium salt precursor. Further, the desired iodonium salt compound is obtained by performing salt exchange with the above-mentioned iodonium salt precursor using a salt having 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 above-mentioned photoacid generator and an acid-reactive compound.

(Photoacid generator)
The content of the photoacid generator in the composition of one aspect 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 calculating the content of the photoacid generator, the organic solvent is not included in the basic composition components.

Examples of other photoacid generators (hereinafter, also referred to as “second photoacid generator”) other than the photoacid generator containing the iodonium salt compound (hereinafter, also referred to as “first photoacid generator”) include General-purpose ionic photoacid generators and non-ionic 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 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 second photoacid generator other than the first photoacid generator is contained, the content thereof shall be 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 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 the alkaline developer, but from the photoacid generator (the first photoacid generator and / or the second photoacid generator) by exposure. It is a compound that becomes soluble in an alkaline developer by deprotecting the protective group from the compound in the exposed portion by the generated acid.

In some aspects 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 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 novolak skeleton, a methacrylate or an acrylate skeleton in which these protecting groups are pendant is preferably used.
The compound having a protecting group to be deprotected by an acid may be a low molecular weight compound containing a protecting group or a unit-containing polymer component having a protecting group.

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 water-based development, it acts on a compound that is soluble in a water-based developer and reduces the solubility of the compound in a water-based developer after polymerization. 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, the compound that reacts with the cross-linking agent and changes its solubility in a developing solution include 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.

When the acid-reactive compound is a polymer component, in addition to the unit containing the deprotecting group, other units usually used in the resist composition may be contained in the polymer component. As the other unit, for example, a unit having at least one of the skeletons selected from the group consisting of a lactone skeleton, a sultone skeleton, a lactam skeleton and the like; 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 of the bonds; a hydroxyalkyl group or a hydroxyaryl group-containing unit; and the like can be mentioned. Further, the photoacid generator may be contained as a unit.

When the acid-reactive compound is contained as a unit of the same polymer, the unit acting as the acid-reactive compound is preferably 5 to 60 mol%, preferably 10 to 50 mol%, based on the total polymer units. Is even more preferable.

(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, sensitizers and the like may be contained 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 in the same molecule, a compound having three nitrogen atoms in the same molecule, and an amide group-containing compound. Examples thereof include urea compounds and nitrogen-containing heterocyclic compounds. Further, as the acid diffusion control agent, a photodisintegrating base that is exposed to light and generates a weak acid by exposure can also be used. Examples of the photodisintegrating base include onium 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, Japanese Patent Application Laid-Open No. 2011-37835, and Japanese Patent Application Laid-Open No. Examples thereof include the compounds described in Kai 2012-173505 and the like.

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 by mass with respect to 100 parts by mass of the basic 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 copolymers, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters. Agents, fluorosurfactants, organosiloxane polymers and the like.

The content of the surfactant is preferably 0.0001 to 2 parts by mass, and more preferably 0.0005 to 1 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 Examples thereof include −naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid and the like. When electron beam exposure is performed under vacuum, 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 basic composition component. It is a department.

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, methyl isobutylketone, 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 solid component containing the basic composition component and the photoacid generator is preferably dissolved in the organic solvent and dissolved in the composition 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 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. Be done.

When the composition of one embodiment of the present invention comprises a polymer, the polymer preferably has a weight average molecular weight of 2000-20000, more preferably 2000-50000, and even more preferably 2000-15000. .. 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.

<5> Device Manufacturing Method One embodiment of the present invention includes a step of forming a resist film by applying the above composition on a substrate, a step of irradiating the resist film with active energy rays, and the above activity. It is a method for manufacturing a device including a step of 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 a substrate having a pattern before obtaining an individualized chip. It may be the manufacturing method of.
One embodiment of the present invention comprises a step of forming a coating film on a substrate using the above composition and a step of exposing the coating film using active energy rays to obtain an interlayer insulating film. It may be a manufacturing method.

The active energy rays are not particularly limited as long as the iodonium salt compound of some aspects of the present invention can generate acid in the resist film after irradiation with the resist film. For example, KrF excimer laser light, UV, etc. , Visible light and the like are 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, a silicon atom-containing substrate such as silicon, silicon nitride, or glass; a metal substrate such as titanium, tantalum, palladium, copper, chromium, or aluminum; and the like can be mentioned.
In one embodiment of the present invention, the active energy rays used to obtain an interlayer insulating film or the like for creating an LSI include UV, KrF excimer laser light, ArF excimer laser light, electron beam, extreme ultraviolet (EUV), and the like. Preferred.

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, and the like, but ^{is preferably 1 J / cm 2} or less or 1000 μC / cm ² or less.
In one aspect of the present invention, the film thickness of the resist film formed by the above composition is preferably 0.1 to 10 μm. The above 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 120. Prebake at ° C. for 1-10 minutes to form a thin film. The film thickness of this coating film is preferably 0.1 to 10 μm.

Hereinafter, some aspects 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 compounds>
(Synthesis Example 1) Synthesis of 2-iodobenzoyl chloride

4.3 g of 2-iodobenzoic acid is dissolved in 30 g of methylene chloride to bring the temperature to 50 ° C. 2.6 g of oxalyl chloride is added dropwise thereto over 10 minutes, and the mixture is stirred at 40 ° C. for 2 hours. By distilling off 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

3.0 g of aluminum chloride is added to 28 g of methylene chloride to bring the temperature to 0 ° C. After adding 2.0 g of anisole to this, 4.2 g of 2-iodobenzoyl chloride obtained in the above Synthesis Example 1 is dissolved in 8.4 g of methylene chloride and added dropwise over 30 minutes. After the dropwise addition, the mixture is stirred at 25 ° C. for 1 hour, 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% sodium hydroxide aqueous 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 filtered off, 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-perfluorobutane sulfonate

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 bring the temperature to 0 ° C. 5.5 g of sulfuric acid and 1.6 g of 35 mass% hydrogen peroxide solution are added dropwise thereto, and the mixture is stirred at 25 ° C. for 1 hour, and then 2.0 g of anisole is added dropwise and stirred at 25 ° C. for another 2 hours. After cooling, 30 g of pure water and 30 g of diisopropyl ether are added. 4.7 g of potassium perfluorobutanesulfonate and 30 g of methylene chloride are added to the aqueous layer obtained by separating the liquids, and the mixture is stirred at 25 ° C. for 1 hour. The organic layer obtained by separating the liquid is washed twice with 30 g of a 3 mass% sodium hydrogen carbonate aqueous solution and twice with 30 g of pure water, and then the organic layer is added dropwise to 50 g of diisopropyl ether to precipitate a solid. The precipitated solid is 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-perfluorobutane sulfonate.

(Synthesis Example 4) Synthesis of 2- (4-methoxybenzoyl) phenyl-2', 4'-dimethoxyphenyliodonium-perfluorobutane sulfonate

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

(Synthesis Example 5) Synthesis of 2- (4-methoxybenzoyl) phenyl-2', 4', 6'-trimethylphenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that mesitylene is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-2', 4', 6'-trimethylphenyliodonium-perfluorobutane sulfonate 8 Obtain 0.8 g.

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

By performing the same operation as in Synthesis Example 3 above except that 2-methoxytoluene is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-4'-methoxy-3'-methylphenyliodonium-perfluorobutane Obtain 8.3 g of sulfonate.

(Synthesis Example 7) Synthesis of 2- (4-methoxybenzoyl) phenyl-3'-cyanomethyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that 2-methoxyphenyl acetonitrile is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-3'-cyanomethyl-4'-methoxyphenyliodonium-perfluoro Obtain 8.9 g of butane sulfonate.

(Synthesis Example 8) Synthesis of 2- (4-methoxybenzoyl) phenyl-3'-acetonyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that 2-methoxyphenylacetone is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-3'-acetonyl-4'-methoxyphenyliodonium-perfluoro Obtain 9.1 g of butane sulfonate.

(Synthesis Example 9) Synthesis of diethylene glycol methylphenyl 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 further added under ice-cooling, and the mixture is stirred at room temperature for 5 hours. Then, 20 g of pure water and 20 g of methylene chloride were added, and the organic layer obtained by separating the liquids was washed 3 times with 20 g of pure water, concentrated, and then silica gel column chromatography (developing solvent: n-hexane / ethyl acetate). By purifying with = 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-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that diethylene glycol methylphenyl ether is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-4'-[2- (2-methoxyethoxy) ethoxy] phenyl Obtain 9.8 g of iodonium-perfluorobutane sulfonate.

(Synthesis Example 11) Synthesis of 4-Phenyloxybutyronitrile

3.4 g of phenol, 6.2 g of potassium carbonate and 3.1 g of 4-chlorobutyronitrile are added to 33 g of dimethyl sulfoxide, and the mixture is stirred at 70 ° C. for 8 hours. Then, 30 g of pure water, 30 g of n-hexane and 30 g of ethyl acetate were added, and the organic layer obtained by separating the liquids was washed once with 40 g of a 5 mass% sodium hydroxide aqueous solution 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-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that 4-phenyloxybutyronitrile is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-4'-(3-cyanopropoxy) phenyliodonium- Obtain 9.1 g of perfluorobutane sulfonate.

(Synthesis Example 13) Synthesis of phenyloxyacetonitrile

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

(Synthesis Example 14) Synthesis of 2- (4-methoxybenzoyl) phenyl-4'-(cyanomethoxy) phenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that phenyloxyacetonitrile is used instead of anisole, 2- (4-methoxybenzoyl) phenyl-4'-(cyanomethoxy) phenyliodonium-perfluorobutane sulfonate is 8 Obtain 0.8 g.

(Synthesis Example 15) Synthesis of 2-iodo-4'-methoxy-α-naphthophenone

2-Iodine-4'-methoxy-α-naphthophenone is obtained 5.5 by performing the same operation as in Synthesis Example 2 except that 1-methoxynaphthalene is used instead of anisole.

(Synthesis Example 16) Synthesis of 2- (4-methoxy-α-naphthoyl) phenyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that 2-iodo-4'-methoxy-α-naphthophenone is used instead of 2-iodo-4'-methoxybenzophenone, 2- (4-methoxy-α-) 9.3 g of naphthoyl) phenyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate is obtained.

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

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

(Synthesis Example 18) Synthesis of 2-fluoro-6-iodo-4'-methoxybenzophenone

5. 2-Fluoro-6-iodo-4'-methoxybenzophenone was obtained by performing the same operation as in Synthesis Example 2 above except that 2-fluoro-6-iodobenzoyl chloride was used instead of 2-iodobenzoyl chloride. Get 1g.

(Synthesis Example 19) Synthesis of 3-fluoro-2- (4-methoxybenzoyl) phenyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that 2-fluoro-6-iodo-4'-methoxybenzophenone is used instead of 2-iodo-4'-methoxybenzophenone, 3-fluoro-2- (4) -Methoxybenzoyl) Phenyl-4'-Methoxyphenyliodonium-Perfluorobutane sulfonate is obtained in an amount of 8.9 g.

(Synthesis Example 20) Synthesis of 4-n-butoxy-2'-iodobenzophenone

Synthesis Example 2 above except that n-butyl phenyl 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 with diisopropyl ether. By performing the same operation as above, 5.4 g of 4-n-butoxy-2'-iodobenzophenone can be obtained.

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

By performing the same operation as in Synthesis Example 3 above except that 4-n-butoxy-2'-iodobenzophenone is used instead of 2-iodo-4'-methoxybenzophenone, 2- (4-n-butoxybenzoyl) Obtain 9.2 g of phenyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate.

(Synthesis Example 22) Synthesis of 4-iodobenzoyl chloride

4.2 g of 4-iodobenzoyl chloride can be obtained by performing the same operation as in Synthesis Example 1 above except that 4-iodobenzoic acid is used instead of 2-iodobenzoic acid.

(Synthesis Example 23) Synthesis of 4-iodo-4'-methoxybenzophenone

By performing the same operation as in Synthesis Example 2 above except that 4-iodobenzoyl chloride is used instead of 2-iodobenzoyl chloride, 4.8 g of 4-iodo-4'-methoxybenzophenone can be obtained.

(Synthesis Example 24) Synthesis of 4- (4-methoxybenzoyl) phenyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate

By performing the same operation as in Synthesis Example 3 above except that 4-iodo-4'-methoxybenzophenone is used instead of 2-iodo-4'-methoxybenzophenone, 4- (4-methoxybenzoyl) phenyl-4' Obtain 8.7 g of -methoxyphenyl iodonium-perfluorobutane sulfonate.

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

By performing the same operation as in Synthesis Example 3 above except that sodium tetrafluoroborate is used instead of potassium perfluorobutanesulfonate, 2- (4-methoxybenzoyl) phenyl-4'-methoxyphenyliodonium-tetrafluoro Obtain 6.2 g of volate.

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

By performing the same operation as in Synthesis Example 3 above except that potassium hexafluorophosphate is used instead of potassium perfluorobutanesulfonate, 2- (4-methoxybenzoyl) phenyl-4'-methoxyphenyliodonium-hexafluoro Obtain 6.9 g of phosphate.

(Synthesis Example 27) Synthesis of 2- (4-methoxybenzoyl) phenyl-4'-methoxyphenyliodonium-tetrakis (pentaflurophenyl) borate

By performing the same operation as in Synthesis Example 3 above except that sodium tetrakis (pentafluorophenyl) borate is used instead of potassium perfluorobutanesulfonate, 2- (4-methoxybenzoyl) phenyl-4'-methoxyphenyl Obtain 13.1 g of iodonium-tetrakis (pentafluorophenyl) borate.

(Comparative Synthesis Example 1) Synthesis of 4-t-butyl-2'-iodobenzophenone

By performing the same operation as in Synthesis Example 2 above except that t-butylbenzene is used instead of anisole, 5.2 g of 4-t-butyl-2'-iodobenzophenone can be obtained.

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

２−ヨード−４'−メトキシベンゾフェノンに代えて４−ｔ−ブチル−２'−ヨードベンゾフェノンを用いる以外は上記合成例３と同様の操作を行うことで、２−（４−ｔ−ブチルベンゾイル）フェニル−４'−メトキシフェニルヨードニウム−パーフルオロブタンスルホネートを９．０ｇ得る。

2- (4-t-Butylbenzoyl) can be obtained by performing the same operation as in Synthesis Example 3 above except that 4-t-butyl-2'-iodobenzophenone is used instead of 2-iodo-4'-methoxybenzophenone. Obtain 9.0 g of phenyl-4'-methoxyphenyliodonium-perfluorobutane sulfonate.

<Synthesis of polymer>
(Synthesis Example 28) Synthesis of Polymer 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. 2.34 g of ethyl 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. The polymer is then 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 8.9 g of the polymer shown below as a white solid. The monomer ratio of the polymer unit in some aspects of the present invention is not limited to the following.

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

<Sensitivity evaluation>
Samples 1 to 10 are prepared as follows. To 3000 mg of cyclohexanone, 500 mg of the above polymer, the above-mentioned iodonium salts 1 to 5 and iodonium salt 8 as photoacid generators, and 0.018 mmol of any of the comparative sulfonium salt and the comparative iodonium salt 1 to 3 shown below were added. Samples are 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 evaluation sample 1 to 13 is applied to a Si wafer on which the prepared sample has been previously treated with hexamethyldisilazane (HMDS), spin-coated, and heated at 110 ° C. to obtain a resist film having a film thickness of 500 nm. ..
Next, the evaluation sample is exposed by a UV exposure apparatus having a emission line of 365 nm through a 1: 1 line having a line width half pitch of 2 μm and a space pattern mask at different exposure amounts. Then heat on a hot plate at 110 ° C. for 1 minute.
After heating, develop with a developing solution (product name: NMD-3, 2.38% by mass aqueous solution of tetramethylammonium hydroxide, manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 1 minute, develop, and rinse with pure water. Get the pattern. Observing this with a microscope, the exposure amount at which the resist is completely peeled off is defined as E _size (minimum exposure amount). Table 1 shows the results of evaluating the minimum exposure amount as the sensitivity. The sensitivity of each sample is calculated by assuming that the sensitivity of the sample to which the iodonium salt 1 is added (Example 1) is 100 and the evaluation result of each sample with respect to the sensitivity as a relative value.

Examples 1 to 6, which are samples containing the 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 tert-butyl group at the 4-position of benzoyl, and Comparative Examples 3 and 4 are via oxygen or respectively. Comparative iodonium salts 3 and 4 which are cyclic by direct bonding are used. In Examples 1 to 6, the acid generation efficiency is improved by increasing the i-ray absorption efficiency, and the sensitivity is higher than that in Comparative Examples 1 to 4 using the comparative onium salt compound.

That is, the iodonium salt compound of some aspects of the present invention has a specific substituent having a higher electron donating property than an alkyl group such as a methoxy group at the 4-position of the benzoyl group, whereby 1 × on the i-line. It ^{has an absorption of 10 6} cm ² / mol or more, and the sensitivity is greatly improved. Further, since the iodonium salt compound of some aspects of the present invention absorbs 400 nm or more and has an absorption of 5 × 10 ⁵ cm ² / mol or less, the acid generation efficiency in visible light is remarkably low, and visible light transmittance is required. It is effective in the case.
Note that FIG. 1 shows the UV spectra of iodonium salts 1 and 2, the comparative sulfonium salt, and the comparative iodonium salt 1.

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

Claims (6)

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

(In the above formula (1), R ¹ is an alkoxy group which may have a cyano group or a 2- (2-methoxyethoxy) ethoxy group and has 1 to 12 carbon atoms.
R ² is an alkyl group which may have a cyano group or an acyl group (-COR ⁶ ), and has 1 to 12 carbon atoms when it has a carbon atom.
R ³ represents a fluorine atom
R ⁴ is an alkoxy group , has 1 to 12 carbon atoms, and has.
R ⁵ is an alkyl group, has 1 to 12 carbon atoms, and has.
R ⁶ is an alkyl group, has 1 to 12 carbon atoms, and has.
m and n are independently integers of 1 respectively.
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 .
d is an integer from 0 to 4
c is an integer from 0 to 4
X ^- represents a counter anion of a monovalent. ) 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 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 a polymer or oligomer having a hydroxyaryl group. A step of applying the composition according to claim 4 or 5 onto a substrate to form a resist film, and
The step of irradiating the resist film with active energy rays and
A method for manufacturing a device, which comprises a step of developing a resist film after irradiating the active energy ray to form a pattern.

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