JP4677353B2 - RESIST COMPOSITION, COMPOUND USED FOR THE RESIST COMPOSITION, AND PATTERN FORMATION METHOD USING THE RESIST COMPOSITION - Google Patents

Description

  The present invention relates to a resist composition whose properties are changed by irradiation with actinic rays or radiation (electron beam, X-ray, EUV, UV, etc.), a compound used in the resist composition, and a pattern using the resist composition. It relates to a forming method. More specifically, a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, a further photofabrication process, a lithographic printing plate, a resist composition used in an acid-curable composition, and the resist composition And a pattern forming method using the resist composition.

  The chemically amplified resist composition generates an acid in the exposed area by irradiation with radiation such as far ultraviolet light, and the acid-catalyzed reaction changes the solubility of the active radiation irradiated area and non-irradiated area in the developer. Pattern forming material for forming a pattern on a substrate.

  When a KrF excimer laser is used as an exposure light source, a resin having a basic skeleton of poly (hydroxystyrene) having a small absorption mainly in the 248 nm region is used as a main component. A pattern is formed, which is a better system than the conventional naphthoquinone diazide / novolak resin system.

On the other hand, when a further short wavelength light source, for example, an ArF excimer laser (193 nm) is used as an exposure light source, the compound having an aromatic group exhibits a large absorption in the 193 nm region. It wasn't.
For this reason, an ArF excimer laser resist containing a resin having an alicyclic hydrocarbon structure has been developed.

A triphenylsulfonium salt is generally known as an acid generator that is a main constituent of a chemically amplified resist (see, for example, Patent Document 1).
However, the acid generator still has many insufficient points, and a resist composition with improved sensitivity and the like is desired.

In addition, when an electron beam, X-ray, EUV light source or the like is used, exposure is performed under vacuum, so that low-boiling compounds such as solvents and resist materials decomposed by high energy volatilize and contaminate the exposure apparatus. Outgassing issues are becoming important. In recent years, various studies have been made on the reduction of outgas, and a radical trap that suppresses volatilization of a low-molecular compound by providing a topcoat layer (see, for example, Patent Document 2) or suppresses decomposition of a polymer. Various attempts such as adding an agent (see, for example, Patent Document 3) have been tried, and an contrivance for reducing the outgas is also desired for the acid generator.
Further, new acid generators are introduced in Patent Document 4, Patent Document 5, and the like.

  On the other hand, Patent Document 6 introduces an example of using a sulfonium salt having a specific structure in a photopolymerization composition containing an epoxy compound or the like.

US Pat. No. 6,548,221 European Patent No. 1480078 specification US Pat. No. 6,680,157 JP 2003-149800 A JP 2004-4557 A US Pat. No. 4,694,029

  The present invention provides a resist composition excellent in sensitivity and outgas characteristics, a compound used in the resist composition, and a pattern forming method using the resist composition.

一般式（Ｉ）中、
Ｒ ¹ はアリール基を表す。
Ｒ ² 〜Ｒ ⁹ は、各々独立に水素原子又は置換基を表し、互いに結合して環を形成してもよい。
Ｚは電子求引性の２価の連結基である。
Ｘ ^n- は、ｎ価のアニオンを表す。
ｎは、１〜３の整数を表す。
ｍは電荷を中和するのに必要なアニオン数を示す。
２．
前記一般式（Ｉ）で表されるスルホニウム塩（Ａ）が、一般式（ＩＩ）で表されるスルホニウム塩化合物であることを特徴とする上記１に記載のレジスト組成物。

一般式（ＩＩ）中、
Ｒ ¹ はアリール基を表す。
Ｒ ² 〜Ｒ ⁹ は、各々独立に水素原子又は置換基を表し、互いに結合して環を形成してもよい。
Ｚ’はスルホン基を表す。
Ｘ ^n- は、ｎ価のアニオンを表す。
ｎは、１〜３の整数を表す。
ｍは電荷を中和するのに必要なアニオン数を示す。
３．
前記一般式（Ｉ）で表されるスルホニウム塩（Ａ）が、一般式（ＩＩＩ）で表されるスルホニウム塩化合物であることを特徴とする上記１に記載のレジスト組成物。

一般式（ＩＩＩ）中、
Ｒ ^1’ はアリール基を表す。
Ｒ ^2’ 〜Ｒ ^9’ は、各々独立に水素原子又は置換基を表し、互いに結合して環を形成してもよい。ただし、Ｒ ^1’ 〜Ｒ ^9’ の少なくとも１つはアルコール性の水酸基を含む基である。
Ｚは電子求引性の２価の連結基である。
Ｘ ^n- は、ｎ価のアニオンを表す。
ｎは、１〜３の整数を表す。
ｍは電荷を中和するのに必要なアニオン数を示す。
４．
更に、Ｘ線、電子線又はＥＵＶで露光することを特徴とする、上記１〜３のいずれか一項に記載のレジスト組成物。
５．
上記１〜４のいずれか一項に記載のレジスト組成物により形成した感光性膜。
６．
上記５に記載の感光性膜を露光、現像する工程を含むことを特徴とするパターン形成方法。
本発明は上記１〜６の構成を有するが、以下、その他についても参考のため記載した。
（１）一般式（Ｉ）で表されるスルホニウム塩（Ａ）を含有することを特徴とするレジスト組成物。

一般式（Ｉ）中、
Ｒ¹はアルキル基又はアリール基を表す。
Ｒ²〜Ｒ⁹は、各々独立に水素原子又は置換基を表し、互いに結合して環を形成してもよい。
Ｚは電子求引性の２価の連結基である。
Ｘ^n-は、ｎ価のアニオンを表す。
ｎは、１〜３の整数を表す。
ｍは電荷を中和するのに必要なアニオン数を示す。 The present invention has the following configuration, which solves the above-described problems of the present invention.
1.
The sulfonium salt (A) represented by the general formula (I), and
A resin (B) that decomposes by the action of an acid and increases the solubility in an alkaline developer,
A resist composition comprising:

In general formula (I),
R ¹ represents an aryl group.
R ^{2 to} R ⁹ each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.
2.
2. The resist composition according to 1 above, wherein the sulfonium salt (A) represented by the general formula (I) is a sulfonium salt compound represented by the general formula (II).

In general formula (II),
R ¹ represents an aryl group.
R ^{2 to} R ⁹ each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
Z ′ represents a sulfone group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.
3.
2. The resist composition according to 1 above, wherein the sulfonium salt (A) represented by the general formula (I) is a sulfonium salt compound represented by the general formula (III).

In general formula (III),
R ^{1 ′} represents an aryl group.
R ^{2 ′ to} R ^{9 ′} each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring. However, at least one of R ^{1 ′ to} R ^{9 ′} is a group containing an alcoholic hydroxyl group.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.
4).
Furthermore, the resist composition according to any one of 1 to 3 above, wherein the resist composition is exposed with an X-ray, an electron beam or EUV.
5.
The photosensitive film | membrane formed with the resist composition as described in any one of said 1-4.
6).
6. A pattern forming method comprising the steps of exposing and developing the photosensitive film according to 5 above.
The present invention has the above-described configurations 1 to 6, but the following are also described for reference.
(1) A resist composition comprising a sulfonium salt (A) represented by the general formula (I).

In general formula (I),
R ¹ represents an alkyl group or an aryl group.
R ^{2 to} R ⁹ each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.

(2) The resist composition as described in (1) above, further comprising a resin (B) that decomposes by the action of an acid and increases the solubility in an alkali developer. The resist composition as described in (1) above, which contains a resin (D) soluble in a developer and an acid crosslinking agent (E) that crosslinks the resin soluble in an alkali developer by the action of an acid. object.
(4) The resist composition as described in (1) to (3) above, which is further exposed to X-rays, electron beams or EUV.

一般式（ＩＩ）中、
Ｒ^1aはアリール基を表す。
Ｒ^2a〜Ｒ^9aは、各々独立に水素原子又は置換基を表し、互いに結合して環を形成してもよい。
Ｘ^n-は、ｎ価のアニオンを表す。
ｎは、１〜３の整数を表す。
ｍは電荷を中和するのに必要なアニオン数を示す。
（２０）
一般式（ＩＩＩ）で表されるスルホニウム塩化合物。

一般式（ＩＩＩ）中、
Ｒ^1bはアルキル基又はアリール基を表す。
Ｒ^2b〜Ｒ^9bは、各々独立に水素原子又は置換基を表し、互いに結合して環を形成してもよい。ただし、Ｒ^2b〜Ｒ^9bの少なくとも１つはアルコール性の水酸基を含む基である。
Ｚは電子求引性の２価の連結基である。
Ｘ^n-は、ｎ価のアニオンを表す。
ｎは、１〜３の整数を表す。
ｍは電荷を中和するのに必要なアニオン数を示す。 The preferred embodiments of the present invention will be further described below.
(5) The positive resist composition as described in (2) above, wherein the resin (B) has a hydroxystyrene structural unit.
(6) The positive resist composition as described in (2) above, wherein the resin (B) contains a repeating unit having a monocyclic or polycyclic hydrocarbon structure.
(7) The resin (B) is a resin containing a repeating unit having an alcoholic hydroxyl group, decomposed by the action of an acid, and increased in solubility in an alkali developer. A positive resist composition.
(8) The repeating unit having an alcoholic hydroxyl group of the resin (B) is a repeating unit containing at least one selected from a monohydroxyadamantane structure, a dihydroxyadamantane structure, or a trihydroxyadamantane structure. The positive resist composition as described in (7) above.
(9) The positive resist composition as described in (2) above, wherein the resin (B) is a resin containing a repeating unit having a lactone structure.
(10) The positive resist composition as described in (2) above, wherein the resin (B) is a resin containing at least one methacrylic ester repeating unit and at least one acrylate repeating unit. .
(11) The positive resist composition as described in (2) above, wherein the resin (B) has a fluorine atom in the main chain or side chain.
(12) The positive resist composition as described in (2) above, wherein the resin (B) has a hexafluoro-2-propanol structure.
(13) The composition further comprises a dissolution inhibiting compound (C) having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer. The positive resist composition according to any one of the above.
(14) The positive type as described in any one of (5) to (13) above, further comprising a basic compound (F) and / or fluorine and / or a silicon-based surfactant (G). Resist composition.
(15) The resin (B) is at least one repeating unit selected from 2-alkyl-2-adamantyl (meth) acrylate or dialkyl (1-adamantyl) methyl (meth) acrylate, at least one repeating unit having a lactone structure, And the positive resist composition as described in (6) above, which contains at least one repeating unit having two or more hydroxyl groups.
(16) The resist composition as described in (15) above, wherein the resin (B) further contains a repeating unit having a carboxy group.
(17) The resin (B) is at least one repeating unit selected from 2-alkyl-2-adamantyl (meth) acrylate or dialkyl (1-adamantyl) methyl (meth) acrylate, and at least one repeating unit having a hydroxystyrene structure. The resist composition as described in (5) above, which contains a seed.
(18) A pattern forming method comprising forming a photosensitive film from the resist composition according to any one of (1) to (17), and exposing and developing the photosensitive film.
(19)
A sulfonium salt compound represented by the general formula (II).

In general formula (II),
R ^1a represents an aryl group.
R ^{2a to} R ^9a each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.
(20)
A sulfonium salt compound represented by the general formula (III).

In general formula (III),
R ^1b represents an alkyl group or an aryl group.
R ^{2b to} R ^9b each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring. However, at least one of R ^{2b to} R ^9b is a group containing an alcoholic hydroxyl group.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.

  According to the present invention, it is possible to provide a resist composition excellent in sensitivity and outgas characteristics, a compound used in the resist composition, and a pattern forming method using the resist composition.

Hereinafter, the present invention will be described in detail.
In addition, in the description of a group (atomic group) in this specification, the description which does not describe substituted and unsubstituted includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

The resist composition of the present invention may be positive or negative.
The positive resist composition of the present invention contains a sulfonium salt (A) represented by the general formula (I) and a resin (B) that decomposes by the action of an acid and increases the solubility in an alkaline developer, If necessary, it further contains a dissolution inhibiting compound (C) having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer.
The negative resist composition of the present invention comprises a sulfonium salt (A) represented by the general formula (I), a resin (D) soluble in an alkali developer, and a resin soluble in the alkali developer by the action of an acid. And an acid crosslinking agent (E) that crosslinks.

[1] A sulfonium compound (A) represented by the general formula (I)
The resist composition of the present invention comprises a sulfonium compound represented by the general formula (I) (hereinafter also simply referred to as a sulfonium salt (A)) as a compound (acid generator) that generates an acid upon irradiation with actinic rays or radiation. contains.

In general formula (I),
R ¹ represents an alkyl group or an aryl group.
R ^{2 to} R ⁹ each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.

The sulfonium compound (A) represented by the general formula (I) has an anion X ⁿ⁻ . As an anion, an organic anion is desirable. An organic anion represents an anion containing at least one carbon atom. Furthermore, the organic anion X ⁿ⁻ is preferably a non-nucleophilic anion.
A non-nucleophilic anion is an anion that has an extremely low ability to cause a nucleophilic reaction, and is an anion that can suppress degradation over time due to an intramolecular nucleophilic reaction. Examples of the non-nucleophilic anion include a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, a tris (alkylsulfonyl) methyl anion, and the like.

Examples of the sulfonate anion include an alkyl sulfonate anion, an aryl sulfonate anion, and a camphor sulfonate anion.
Examples of the non-nucleophilic carboxylate anion include an alkylcarboxylate anion, an arylcarboxylate anion, and an aralkylcarboxylate anion.
The alkyl moiety in the alkyl sulfonate anion may be an alkyl group or a cycloalkyl group, and preferably an alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms, such as a methyl group or an ethyl group. Group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group Tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, boronyl group and the like.
The aryl group in the aryl sulfonate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

The alkyl group, cycloalkyl group, and aryl group in the alkyl sulfonate anion and aryl sulfonate anion may further have a substituent. Examples of the further substituent that may be included include a nitro group, a halogen atom, and the like. Atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group, hydroxyl group, amino group, cyano group, alkoxy group (preferably having 1 to 5 carbon atoms), cycloalkyl group (preferably having 3 to 15 carbon atoms) An aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably 2 to 7 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably 2 to 7 carbon atoms). And the like. About the aryl group and ring structure which each group has, an alkyl group (preferably C1-C15) can further be mentioned as a substituent.
Examples of the alkyl moiety in the alkylcarboxylate anion include the same alkyl group and cycloalkyl group as in the alkylsulfonate anion.

Examples of the aryl group in the arylcarboxylate anion include the same aryl groups as in the arylsulfonate anion.
The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 6 to 12 carbon atoms, such as a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylmethyl group.
The alkyl group, cycloalkyl group, aryl group and aralkyl group in the alkylcarboxylate anion, arylcarboxylate anion and aralkylcarboxylate anion may further have a substituent, and as a further substituent which may have Examples thereof include the same halogen atom, alkyl group, cycloalkyl group, alkoxy group and alkylthio group as in the aryl sulfonate anion.
Examples of the sulfonylimide anion include saccharin anion.

  The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methyl anion is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, An isobutyl group, a sec-butyl group, a pentyl group, a neopentyl group, and the like can be given. These alkyl groups may further have a substituent, and examples of further substituents that may be included include a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, and an alkylthio group. An alkyl group substituted with a fluorine atom is preferred.

  Examples of other non-nucleophilic anions include fluorinated phosphorus, fluorinated boron, and fluorinated antimony.

  As the non-nucleophilic anion, a sulfonate anion is preferable. Specific preferred sulfonate anions include trifluoromethane sulfonate anion, pentafluoroethane sulfonate anion, heptafluoropropane sulfonate anion, perfluorobutane sulfonate anion, perfluorohexane sulfonate anion, perfluorooctane sulfonate. Anion, pentafluorobenzenesulfonate anion, 3,5-bistrifluoromethylbenzenesulfonate anion, 2,4,6-triisopropylbenzenesulfonate anion, perfluoroethoxyethanesulfonate anion, 2,3,5,6- Tetrafluoro-4-dodecyloxybenzenesulfonate anion, methanesulfonate anion, p-toluenesulfonate anion, 3,5-bistrifluorobenzenesulfonate anion, pentafluoroben Nsuruhon anion, such as 2,4,6-trimethylbenzene sulfonate anions.

  The anion which the sulfonium salt (A) has with the cation represented by the general formula (I) may be monovalent or divalent. When the anion is divalent or higher, the sulfonium salt (A) can have two or more cations represented by the general formula (I).

As the alkyl group for R ^1, a linear or branched alkyl group having 1 to 20 carbon atoms is preferable, and a linear or branched alkyl group having 1 to 12 carbon atoms is more preferable. Group, propyl group, isopropyl group, n-butyl group, isobutyl group, and the like. The cycloalkyl group is preferably a cycloalkyl group having 3 to 20 carbon atoms, more preferably a cycloalkyl group having 5 to 15 carbon atoms, such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a norbornyl group, an adamantyl group. Etc.
The aryl group in R ^1, for example, a phenyl group, a naphthyl group, preferably a phenyl group.
R ¹ is preferably an aryl group, which may be unsubstituted or substituted. R ¹ is more preferably an aryl group having a substituent, and particularly preferably a phenyl group having a substituent.

Examples of further substituents that the alkyl group and aryl group in R ¹ may have include, for example, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cyano group, a hydroxyl group, a nitro group, and a carboxyl group. , Alkoxy group, aryloxy group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group Alkyl and arylsulfonylamino groups, mercapto groups, alkylthio groups, arylthio groups, sulfamoyl groups, sulfo groups, alkyl and arylsulfinyl groups, alkyl and arylsulfonyl groups, acyl groups, Le oxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an imido group, a silyl group, a ureido group, but be mentioned as examples.

Preferably, the alkyl group and aryl group in R ¹ further have an alkyl group, alkenyl group, alkynyl group, alkoxy group, acyloxy group, sulfamoylamino group, alkyl and arylsulfonylamino group, alkylthio group, arylthio group Sulfamoyl group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, more preferably alkyl group, alkoxy group, alkylsulfonylamino group, alkylthio group, A sulfamoyl group, an alkyl and arylsulfonyl group, and an alkoxycarbonyl group;
These substituents may further have a substituent, and examples of the substituent include the substituents for R ¹ mentioned above.

R ^{2 to} R ⁹ are each independently a hydrogen atom or a substituent. Examples of the substituent include a halogen atom, an alkyl group (including a cycloalkyl group, a bicycloalkyl group, and a tricycloalkyl group), an alkenyl group ( (Including cycloalkenyl groups and bicycloalkenyl groups), alkynyl groups, aryl groups, cyano groups, hydroxyl groups, nitro groups, carboxyl groups, alkoxy groups, aryloxy groups, silyloxy groups, acyloxy groups, carbamoyloxy groups, alkoxycarbonyloxy groups Aryloxycarbonyloxy group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, Rufamoiru group, a sulfo group, an alkyl or arylsulfinyl group, alkyl or arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an imido group, a silyl group, a ureido group, but be mentioned as examples.

^Two of R ^{2 to} R ⁹ can be combined with a ring (aromatic or non-aromatic hydrocarbon ring or heterocyclic ring to form a polycyclic condensed ring. Ring, naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, triphenylene ring, naphthacene ring, biphenyl ring, furan ring, thiophene ring, oxazole ring, thiazole ring, benzofuran ring, benzothiophene ring, isobenzofuran ring, etc. .) Can also be formed.

R ^{2 to} R ⁹ are preferably a hydrogen atom or an electron withdrawing group. Specific examples of the electron withdrawing group include, for example, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom). , Cyano group, nitro group, carboxyl group, acyloxy group (preferably formyloxy group, substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms) , For example, formyloxy, acetyloxy, pivaloyloxy, stearoyloxy, benzoyloxy, p-methoxyphenylcarbonyloxy), a carbamoyloxy group (preferably a substituted or unsubstituted carbamoyloxy group having 1 to 30 carbon atoms, such as N , N-dimethylcarbamoyloxy, N, N-die Carbamoyloxy, morpholinocarbonyloxy, N, N-di-n-octylaminocarbonyloxy, Nn-octylcarbamoyloxy), alkoxycarbonyloxy group (preferably substituted or unsubstituted alkoxycarbonyloxy having 2 to 30 carbon atoms) A group such as methoxycarbonyloxy, ethoxycarbonyloxy, t-butoxycarbonyloxy, n-octylcarbonyloxy), an aryloxycarbonyloxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy group having 7 to 30 carbon atoms, For example, phenoxycarbonyloxy, p-methoxyphenoxycarbonyloxy, pn-hexadecyloxyphenoxycarbonyloxy), acylamino group (preferably formylamino group, carbon number 1 To 30 substituted or unsubstituted alkylcarbonylamino groups, substituted or unsubstituted arylcarbonylamino groups having 6 to 30 carbon atoms, such as formylamino, acetylamino, pivaloylamino, lauroylamino, benzoylamino, 3,4,5 -Tri-n-octyloxyphenylcarbonylamino), an aminocarbonylamino group (preferably a substituted or unsubstituted aminocarbonylamino having 1 to 30 carbon atoms, such as carbamoylamino, N, N-dimethylaminocarbonylamino, N , N-diethylaminocarbonylamino, morpholinocarbonylamino), alkoxycarbonylamino group (preferably a substituted or unsubstituted alkoxycarbonylamino group having 2 to 30 carbon atoms, such as methoxycarbonylamino, ethoxy Carbonylamino, t-butoxycarbonylamino, n-octadecyloxycarbonylamino, N-methyl-methoxycarbonylamino), aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms) , For example, phenoxycarbonylamino, p-chlorophenoxycarbonylamino, mn-octyloxyphenoxycarbonylamino), a sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms) , For example, sulfamoylamino, N, N-dimethylaminosulfonylamino, Nn-octylaminosulfonylamino), alkyl and arylsulfonylamino groups (preferably substituted or unsubstituted having 1 to 30 carbon atoms) Alkylsulfonylamino, substituted or unsubstituted arylsulfonylamino having 6 to 30 carbon atoms, such as methylsulfonylamino, butylsulfonylamino, phenylsulfonylamino, 2,3,5-trichlorophenylsulfonylamino, p-methylphenylsulfonylamino ), A sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms such as N-ethylsulfamoyl, N- (3-dodecyloxypropyl) sulfamoyl, N, N-dimethylsulfamoyl, N-acetylsulfamoyl, N-benzoylsulfamoyl, N- (N′-phenylcarbamoyl) sulfamoyl), alkyl and arylsulfinyl groups (preferably substituted or unsubstituted alkylsulfi having 1 to 30 carbon atoms) Groups, substituted or unsubstituted arylsulfinyl groups of 6 to 30 such as methylsulfinyl, ethylsulfinyl, phenylsulfinyl, p-methylphenylsulfinyl), alkyl and arylsulfonyl groups (preferably substituted of 1 to 30 carbon atoms) Or an unsubstituted alkylsulfonyl group, a 6-30 substituted or unsubstituted arylsulfonyl group such as methylsulfonyl, ethylsulfonyl, phenylsulfonyl, p-methylphenylsulfonyl), an acyl group (preferably a formyl group, 2 carbon atoms) To a substituted or unsubstituted alkylcarbonyl group having 7 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, or a heterocyclic ring bonded to the carbonyl group at a substituted or unsubstituted carbon atom having 4 to 30 carbon atoms Carbonyl group, eg For example, acetyl, pivaloyl, 2-chloroacetyl, stearoyl, benzoyl, pn-octyloxyphenylcarbonyl, 2-pyridylcarbonyl, 2-furylcarbonyl), an aryloxycarbonyl group (preferably a substitution of 7 to 30 carbon atoms) Or an unsubstituted aryloxycarbonyl group such as phenoxycarbonyl, o-chlorophenoxycarbonyl, m-nitrophenoxycarbonyl, pt-butylphenoxycarbonyl), an alkoxycarbonyl group (preferably a C 2-30 substituted or An unsubstituted alkoxycarbonyl group such as methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl, n-octadecyloxycarbonyl), a carbamoyl group (preferably a substituted or unsubstituted group having 1 to 30 carbon atoms) Substituted carbamoyl, for example, carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N, N-di-n-octylcarbamoyl, N- (methylsulfonyl) carbamoyl).
R ^{2 to} R ⁹ preferably contain an alcoholic hydroxyl group. The alcoholic hydroxyl group is a hydroxyl group substituted with an alkyl group.

Z represents an electron-attracting divalent linking group, specifically, a carbonyl group, a sulfoxide group, a sulfone group, —COO—, —CONH—, —SO ₂ NH—, —CF ₂ —, —CF ₂ CF ₂ -,-OCF ₂ O-,-CF ₂ OCF ₂ -,-SS-,-CH ₂ SO ₂ CH ₂ -,-CH ₂ COCH ₂ -,-COCF ₂ CO-,-COCO-,-OCOO- .-OSO ₂ O-.
Z is preferably a carbonyl group, a sulfoxide group, a sulfone group, -COO-, -CONH-, -SO2NH-, -CF2-, -CF2CF2-, -COCO-, and particularly preferably a carbonyl group, a sulfoxide group, a sulfone group And more preferably a sulfone group.

  As the sulfonium salt (A) represented by the general formula (I), a sulfonium salt compound represented by the general formula (II) or (III) is also preferable.

In general formula (II),
R ¹ represents an aryl group.
R ^{2 to} R ⁹ each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
Z ′ represents a sulfone group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.

In general formula (III),
R ^{1 ′} represents an alkyl group or an aryl group.
R ^{2 ′ to} R ^{9 ′} each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring. However, at least one of R ^{1 ′ to} R ^{9 ′} is a group containing an alcoholic hydroxyl group.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.

  Specific examples of the sulfonium salt (A) represented by the general formula (I) are shown below, but are not limited thereto.

  The sulfonium salt (A) represented by the general formula (I) may be bonded to the resin (B) described later. Although the example of the repeating structural unit in the case of couple | bonding with resin below is given, this invention is not limited to these.

  The compound of general formula (I) is obtained by oxidizing a cyclic sulfide compound with hydrogen peroxide to form a sulfoxide, reacting the diphenyl sulfoxide compound in the presence of an acid catalyst to synthesize a triphenylsulfonium salt structure, and then exchanging the salt with the desired anion. Can be synthesized.

  The content of the sulfonium salt (A) is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, still more preferably 1 to 7% by mass, based on the total solid content of the composition. .

(Combination acid generator)
In the present invention, in addition to the compound (A), a compound capable of decomposing upon irradiation with actinic rays or radiation to generate an acid (acid generator) may be further used.

  The amount of the photoacid generator that can be used in combination is usually 100/0 to 20/80, preferably 100/0 to 40/60, and more preferably in molar ratio (compound (A) / other acid generator). 100/0 to 50/50.

  As such photoacid generators that can be used in combination, they are used in photocationic photoinitiators, photoinitiators of radical photopolymerization, photodecolorants of dyes, photochromic agents, or microresists. Known compounds that generate acids upon irradiation with actinic rays or radiation and mixtures thereof can be appropriately selected and used.

  Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  Further, a group that generates an acid upon irradiation with these actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the polymer, for example, US Pat. No. 3,849,137, German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in JP-A 63-146029 can be used.

  Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Among the compounds capable of decomposing upon irradiation with actinic rays or radiation that may be used in combination, preferred compounds include compounds represented by the following general formulas (ZI), (ZII), and (ZIII). it can.

In the above general formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.
The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Z ⁻ represents a non-nucleophilic anion.

Examples of the non-nucleophilic anion as Z ⁻ include a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methyl anion.

  A non-nucleophilic anion is an anion that has an extremely low ability to cause a nucleophilic reaction, and is an anion that can suppress degradation over time due to an intramolecular nucleophilic reaction. This improves the temporal stability of the resist.

  Examples of the sulfonate anion include an alkyl sulfonate anion, an aryl sulfonate anion, and a camphor sulfonate anion.

  Examples of the carboxylate anion include an alkylcarboxylate anion, an arylcarboxylate anion, and an aralkylcarboxylate anion.

  The alkyl moiety in the alkyl sulfonate anion may be an alkyl group or a cycloalkyl group, and preferably an alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms, such as a methyl group or an ethyl group. Group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group Tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, boronyl group and the like.

  The aryl group in the aryl sulfonate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

  Examples of the substituent of the alkyl group, cycloalkyl group and aryl group in the alkyl sulfonate anion and aryl sulfonate anion include, for example, a nitro group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group, Hydroxyl group, amino group, cyano group, alkoxy group (preferably 1 to 5 carbon atoms), cycloalkyl group (preferably 3 to 15 carbon atoms), aryl group (preferably 6 to 14 carbon atoms), alkoxycarbonyl group (preferably May include 2 to 7 carbon atoms, an acyl group (preferably 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably 2 to 7 carbon atoms), and the like. About the aryl group and ring structure which each group has, an alkyl group (preferably C1-C15) can further be mentioned as a substituent.

  Examples of the alkyl moiety in the alkylcarboxylate anion include the same alkyl group and cycloalkyl group as in the alkylsulfonate anion.

  Examples of the aryl group in the arylcarboxylate anion include the same aryl groups as in the arylsulfonate anion.

  The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 6 to 12 carbon atoms, such as a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylmethyl group.

  Examples of the alkyl group, cycloalkyl group, aryl group and aralkyl group substituent in the alkylcarboxylate anion, arylcarboxylate anion and aralkylcarboxylate anion include, for example, the same halogen atom, alkyl group as in the arylsulfonate anion, A cycloalkyl group, an alkoxy group, an alkylthio group, etc. can be mentioned.

  Examples of the sulfonylimide anion include saccharin anion.

  The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methyl anion is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, An isobutyl group, a sec-butyl group, a pentyl group, a neopentyl group, and the like can be given. Examples of the substituent of these alkyl groups include a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, and an alkylthio group, and an alkyl group substituted with a fluorine atom is preferable.

  Examples of other non-nucleophilic anions include fluorinated phosphorus, fluorinated boron, and fluorinated antimony.

Examples of the non-nucleophilic anion of Z ⁻ include an alkanesulfonic acid anion in which the α-position of the sulfonic acid is substituted with a fluorine atom, an arylsulfonic acid anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group having a fluorine atom And a tris (alkylsulfonyl) methide anion in which the alkyl group is substituted with a fluorine atom. The non-nucleophilic anion is particularly preferably a perfluoroalkanesulfonic acid anion having 4 to 8 carbon atoms, a benzenesulfonic acid anion having a fluorine atom, most preferably nonafluorobutanesulfonic acid anion, perfluorooctanesulfonic acid anion, penta Fluorobenzenesulfonate anion, 3,5-bis (trifluoromethyl) benzenesulfonate anion.

Examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include BR> A, for example, corresponding groups in the compounds (Z1-1), (Z1-2) and (Z1-3) described later.

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (ZI) is, at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) It may be a compound.

  More preferable examples of the (ZI) component include compounds (Z1-1), (Z1-2), and (Z1-3) described below.

Compound (Z1-1) is at least one of aryl group R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compounds, namely, compounds containing an arylsulfonium as a cation.

In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be an aryl group with the remaining being an alkyl group or a cycloalkyl group.

  Examples of the arylsulfonium compound include a triarylsulfonium compound, a diarylalkylsulfonium compound, and an aryldialkylsulfonium compound.

  The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.

  The alkyl group or cycloalkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, such as a methyl group, Examples thereof include an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.

Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, most preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (Z1-2) will be described.
Compound (Z1-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group not containing an aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, 2-oxocycloalkyl group, alkoxy group. A carbonylmethyl group, most preferably a linear or branched 2-oxoalkyl group.

The alkyl group and cycloalkyl group of R ₂₀₁ to R _203, preferably a linear or branched alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups of several 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group). More preferred examples of the alkyl group include a 2-oxoalkyl group and an alkoxycarbonylmethyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

The 2-oxoalkyl group may be either linear or branched, and a group having> C = O at the 2-position of the above alkyl group is preferable.
The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the cycloalkyl group.

  The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, butyl group, pentyl group).

R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

Two members out of R _{201 to} R ₂₀₃ may combine to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

  The compound (Z1-3) is a compound represented by the following general formula (Z1-3), and is a compound having a phenacylsulfonium salt structure.

R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or a halogen atom.
R _6c and R _7c represent a hydrogen atom, an alkyl group, or a cycloalkyl group.
R _x and R _y each independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.

Any two or more of R _{1c to} R _5c , and R _x and R _y may be bonded to each other to form a ring structure, and this ring structure includes an oxygen atom, a sulfur atom, an ester bond, and an amide bond. May be included.

Zc ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ⁻ in the general formula (ZI).

The alkyl group as R _{1c to} R _{5c may} be either linear or branched, for example, an alkyl group having 1 to 20 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms ( Examples thereof include a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, and a linear or branched pentyl group. The cycloalkyl group is, for example, a cyclic group having 3 to 8 carbon atoms. An alkyl group (for example, a cyclopentyl group, a cyclohexyl group) can be mentioned.

The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).

Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _1c to R _5c is 2 to 2. 15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group and cycloalkyl group as R _x and R _y include the same alkyl group and cycloalkyl group as in R _{1c to} R _5c, and include a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxy group. A carbonylmethyl group is more preferred.

Examples of the 2-oxoalkyl group and 2-oxocycloalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _5c .

Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as in R _{1c to} R _5c .

Examples of the group formed by combining R _x and R _y include a butylene group and a pentylene group.

R _x and R _y are preferably an alkyl group or cycloalkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more alkyl groups or cycloalkyl groups.

In formula (ZII) and (ZIII), R ₂₀₄ ~R ₂₀₇ each independently represents an aryl group, an alkyl group or a cycloalkyl group.

Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group.

The alkyl group and cycloalkyl group in R ₂₀₄ to R _207, preferably a linear or branched alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups of several 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group).

The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (e.g., 6 carbon atoms 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.

Z ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of Z ^{− in} formula (ZI).

  Of the compounds that decompose upon irradiation with actinic rays or radiation that may be used in combination, preferred compounds further include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI). be able to.

In general formulas (ZIV) to (ZVI), Ar ₃ and Ar ₄ each independently represents an aryl group.

R ₂₀₆ , R ₂₀₇ and R _{208 each} represents an alkyl group, a cycloalkyl group or an aryl group.
A represents an alkylene group, an alkenylene group or an arylene group.

Among the compounds that may be used in combination and decompose upon irradiation with actinic rays or radiation to generate an acid, compounds represented by general formulas (ZI) to (ZIII) are more preferable.
Further, as a compound that decomposes upon irradiation with actinic rays or radiation that may be used in combination, a compound that generates a sulfonic acid having one sulfonic acid group is preferable, and a monovalent perfluoroalkanesulfone is more preferable. A compound that generates an acid, or a compound that generates an aromatic sulfonic acid substituted with a fluorine atom or a group containing a fluorine atom, particularly preferably a sulfonium salt of monovalent perfluoroalkanesulfonic acid.

  Of the compounds that decompose upon irradiation with actinic rays or radiation that may be used in combination, particularly preferred examples are listed below.

[2] (B) Resin that decomposes by the action of an acid and increases the solubility in an alkaline developer (hereinafter also referred to as “component (B)”)
The resin (acid-decomposable resin) that is decomposed by the acid used in the positive photosensitive composition of the present invention and has increased solubility in an alkaline developer is the main chain or side chain of the resin, or the main chain and side. It is a resin having a group that can be decomposed by an acid (hereinafter also referred to as “acid-decomposable group”) in both chains. Among these, a resin having a group capable of decomposing with an acid in the side chain is more preferable.

A group preferable as a group that can be decomposed by an acid is a group in which a hydrogen atom of a —COOH group or —OH group is substituted with a group capable of leaving with an acid.
In the present invention, the acid-decomposable group is an acetal group or a tertiary ester group.

  The base resin in the case where these acid-decomposable groups are bonded as side chains is an alkali-soluble resin having —OH or —COOH groups in the side chains. For example, the alkali-soluble resin mentioned later can be mentioned.

  The alkali dissolution rate of these alkali-soluble resins is preferably 170 A / second or more as measured with 0.261 N tetramethylammonium hydroxide (TMAH) (23 ° C.). Particularly preferably, it is 330 A / second or more (A is angstrom).

  From this point of view, particularly preferred alkali-soluble resins are o-, m-, p-poly (hydroxystyrene) and copolymers thereof, hydrogenated poly (hydroxystyrene), halogen or alkyl-substituted poly (hydroxystyrene). Hydroxystyrene structural units such as a part of poly (hydroxystyrene), O-alkylated or O-acylated product, styrene-hydroxystyrene copolymer, α-methylstyrene-hydroxystyrene copolymer, hydrogenated novolak resin, etc. It is an alkali-soluble resin.

  Preferred examples of the repeating unit having an acid-decomposable group in the present invention include t-butoxycarbonyloxystyrene, 1-alkoxyethoxystyrene, (meth) acrylic acid tertiary alkyl ester, and the like. Alkyl-2-adamantyl (meth) acrylate and dialkyl (1-adamantyl) methyl (meth) acrylate are more preferred.

  The component (B) used in the present invention is decomposed with an acid into an alkali-soluble resin as disclosed in European Patent No. 254853, JP-A-2-25850, JP-A-3-223860, JP-A-4-251259, and the like. It can be obtained by reacting a precursor of a group capable of reacting or copolymerizing an alkali-soluble resin monomer having a group capable of decomposing with an acid with various monomers.

  Specific examples of the component (B) used in the present invention are shown below, but the present invention is not limited thereto. p-t-butoxystyrene / p-hydroxystyrene copolymer, p- (t-butoxycarbonyloxy) styrene / p-hydroxystyrene copolymer, p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene Copolymer, 4- (t-butoxycarbonylmethyloxy) -3-methylstyrene / 4-hydroxy-3-methylstyrene copolymer, p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene (10 % Hydrogenated) copolymer, m- (t-butoxycarbonylmethyloxy) styrene / m-hydroxystyrene copolymer, o- (t-butoxycarbonylmethyloxy) styrene / o-hydroxystyrene copolymer, p -(Cumyloxycarbonylmethyloxy) styrene / p-hydroxy Tylene copolymer, cumyl methacrylate / methyl methacrylate copolymer, 4-t-butoxycarbonylstyrene / dimethyl maleate copolymer, benzyl methacrylate / tetrahydropyranyl methacrylate copolymer, p- (t-butoxycarbonylmethyloxy) ) Styrene / p-hydroxystyrene / styrene copolymer, pt-butoxystyrene / p-hydroxystyrene / fumaronitrile copolymer, tert-butoxystyrene / hydroxyethyl methacrylate copolymer, styrene / N- (4-hydroxy) Phenyl) maleimide / N- (4-t-butoxycarbonyloxyphenyl) maleimide copolymer, p-hydroxystyrene / t-butylmethacrylate copolymer, styrene / p-hydroxystyrene / t-butylmethacrylate Copolymer, p-hydroxystyrene / t-butyl acrylate copolymer, styrene / p-hydroxystyrene / t-butyl acrylate copolymer, p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene / N -Methylmaleimide copolymer, t-butyl methacrylate / 1-adamantylmethyl methacrylate copolymer, p-hydroxystyrene / t-butyl acrylate / p-acetoxystyrene copolymer, p-hydroxystyrene / t-butyl acrylate / p -(T-butoxycarbonyloxy) styrene copolymer, p-hydroxystyrene / t-butyl acrylate / p- (t-butoxycarbonylmethyloxy) styrene copolymer,

  In the above specific example, tBu represents a t-butyl group.

  The content of the group that can be decomposed by an acid is determined by the number of groups (B) that can be decomposed by an acid in the resin and the number of alkali-soluble groups that are not protected by a group capable of leaving by an acid (S). B + S). The content is preferably 0.01 to 0.7, more preferably 0.05 to 0.50, and still more preferably 0.05 to 0.40.

  When the positive photosensitive composition of the present invention is irradiated with ArF excimer laser light, the resin of component (B) has a monocyclic or polycyclic alicyclic hydrocarbon structure and is decomposed by the action of an acid. A resin that increases the solubility in an alkali developer is preferable.

  As a resin that has a monocyclic or polycyclic alicyclic hydrocarbon structure, decomposes by the action of an acid, and increases its solubility in an alkaline developer (hereinafter also referred to as “alicyclic hydrocarbon-based acid-decomposable resin”) , At least selected from the group consisting of repeating units having a partial structure containing an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pVI) and repeating units represented by the following general formula (II-AB) It is preferable that it is resin containing 1 type.

In general formulas (pI) to (pVI),
R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z is an atom necessary for forming a cycloalkyl group together with a carbon atom. Represents a group.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or R ₁₅ , Any of R ₁₆ represents a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group, provided that at least one of R _{17 to} R ₂₁ is cyclo Represents an alkyl group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group, provided that at least one of R _{22 to} R ₂₅ is cyclo Represents an alkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In the formula (II-AB),
R ₁₁ ′ and R ₁₂ ′ each independently represents a hydrogen atom, a cyano group, a halogen atom or an alkyl group.
Z ′ represents an atomic group for forming an alicyclic structure containing two bonded carbon atoms (C—C).

  The general formula (II-AB) is more preferably the following general formula (II-A) or general formula (II-B).

In the formulas (II-A) and (II-B),
R ₁₃ ′ to R ₁₆ ′ each independently represents a hydrogen atom, a halogen atom, a cyano group, —COOH, —COOR ₅ , a group that decomposes by the action of an acid, —C (═O) —XA′—R. ₁₇ ′ represents an alkyl group or a cycloalkyl group.
Wherein, R ₅ represents an alkyl group, a cycloalkyl group, or -Y group shown below.
X represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.
A ′ represents a single bond or a divalent linking group.
Further, at least two of R ₁₃ ′ to R ₁₆ ′ may be bonded to form a ring. n represents 0 or 1.
R ₁₇ ′ represents —COOH, —COOR ₅ , —CN, a hydroxyl group, an alkoxy group, —CO—NH—R ₆ , —CO—NH—SO ₂ —R ₆ or the following —Y group.
R ₆ represents an alkyl group or a cycloalkyl group.

  The -Y group;

In the —Y group, R ₂₁ ′ to R ₃₀ ′ each independently represents a hydrogen atom or an alkyl group. a and b represent 1 or 2;

In the general formulas (pI) to (pVI), the alkyl group in R _{12 to} R ₂₅ represents a linear or branched alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group.

  In addition, examples of the substituent that each alkyl group and alkoxy group may have include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), an acyl group, and an acyloxy group. Group, cyano group, hydroxyl group, carboxy group, alkoxycarbonyl group, nitro group and the like.

The cycloalkyl group in R _{11 to} R ₂₅ or the cycloalkyl group formed by Z and the carbon atom may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These cycloalkyl groups may have a substituent.

  Preferred cycloalkyl groups include adamantyl group, noradamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecanyl group, A cyclododecanyl group can be mentioned. More preferable examples include an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group.

  Examples of the substituent for these cycloalkyl groups include an alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably selected from the group consisting of a methyl group, an ethyl group, a propyl group, and an isopropyl group. As said alkoxy group, a C1-C4 methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. can be mentioned. Examples of the substituent that the alkyl group, alkoxy group, alkoxycarbonyl group and the like may further have include a hydroxyl group, a halogen atom, and an alkoxy group.

  The structures represented by the general formulas (pI) to (pVI) in the resin can be used for protecting alkali-soluble groups. Examples of the alkali-soluble group include various groups known in this technical field.

  Specific examples include a carboxylic acid group, a sulfonic acid group, a phenol group, and a thiol group, and a carboxylic acid group and a sulfonic acid group are preferable.

  As the alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI) in the above resin, the hydrogen atom of the carboxyl group is preferably substituted with the structure represented by the general formula (pI) to (PVI). Structure.

  As the repeating unit having an alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI), a repeating unit represented by the following general formula (pA) is preferable.

Here, R represents a hydrogen atom, a halogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups. Represents.
Ra represents any group of the above formulas (pI) to (pVI).

  The repeating unit represented by the general formula (pA) is most preferably a repeating unit of 2-alkyl-2-adamantyl (meth) acrylate and dialkyl (1-adamantyl) methyl (meth) acrylate.

  Specific examples of the repeating unit represented by the general formula (pA) are shown below.

In the general formula (II-AB), R ₁₁ ′ and R ₁₂ ′ each independently represent a hydrogen atom, a cyano group, a halogen atom, or an alkyl group.
Z ′ represents an atomic group for forming an alicyclic structure containing two bonded carbon atoms (C—C).

Examples of the halogen atom in R ₁₁ ′ and R ₁₂ ′ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

The alkyl group in R ₁₁ ′, R ₁₂ ′, and R ₂₁ ′ to R ₃₀ ′ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms. A linear or branched alkyl group, more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a t-butyl group.

  Examples of the further substituent in the above alkyl group include a hydroxyl group, a halogen atom, a carboxy group, an alkoxy group, an acyl group, a cyano group, and an acyloxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group having 1 to 4 carbon atoms. Examples of the acyl group include a formyl group and an acetyl group, and examples of the acyloxy group include an acetoxy group.

  The atomic group for forming the alicyclic structure of Z ′ is an atomic group that forms a repeating unit of an alicyclic hydrocarbon which may have a substituent in a resin, and among them, a bridged type alicyclic group. An atomic group for forming a bridged alicyclic structure forming a cyclic hydrocarbon repeating unit is preferred.

Examples of the skeleton of the alicyclic hydrocarbon formed include the same alicyclic hydrocarbon groups as R _{11 to} R _{25 in} the general formulas (pI) to (pVI).

The alicyclic hydrocarbon skeleton may have a substituent. Examples of such a substituent include R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or (II-B).

  Among the repeating units having the bridged alicyclic hydrocarbon, the repeating unit represented by the general formula (II-A) or (II-B) is more preferable.

In the alicyclic hydrocarbon-based acid-decomposable resin according to the present invention, the acid-decomposable group may be contained in the aforementioned —C (═O) —XA′—R ₁₇ ′, or may be represented by the general formula (II- AB) may be included as a substituent for Z ′.

The structure of the acid-decomposable group is represented by —C (═O) —X ₁ —R ₀ .
In the formula, R ₀ is a tertiary alkyl group such as t-butyl group or t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxy. 1-alkoxyethyl group such as ethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3- An oxocyclohexyl ester group, a 2-methyl-2-adamantyl group, a mevalonic lactone residue and the like can be mentioned. X ₁ has the same meaning as X above.

Examples of the halogen atom in R ₁₃ ′ to R ₁₆ ′ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

The alkyl group in R ₅ , R ₆ and R ₁₃ ′ to R ₁₆ ′ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear chain having 1 to 6 carbon atoms. Or a branched alkyl group, more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a t-butyl group.

Examples of the cycloalkyl group in R ₅ , R ₆ , and R ₁₃ ′ to R ₁₆ ′ are monocyclic cyclic alkyl groups and bridged hydrocarbons, such as cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, 2-methyl-2-adamantyl group, norbornyl group, boronyl group, isobornyl group, tricyclodecanyl group, dicyclopentenyl group, nobornane epoxy group, menthyl group, isomenthyl group, neomenthyl group, tetracyclododecanyl group, etc. Can be mentioned.

Examples of the ring formed by combining at least two of R ₁₃ ′ to R ₁₆ ′ include rings having 5 to 12 carbon atoms such as cyclopentene, cyclohexene, cycloheptane, and cyclooctane.

Examples of the alkoxy group for R ₁₇ ′ include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group having 1 to 4 carbon atoms.

  Examples of further substituents in the alkyl group, cycloalkyl group, and alkoxy group include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group, an acyloxy group, an alkyl group, and a cycloalkyl group. . Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group. Examples thereof include an acetoxy group.

  Examples of the alkyl group and cyclic hydrocarbon group include those listed above.

  The divalent linking group of A ′ is one or two selected from the group consisting of an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, and a urea group. Combinations of the above groups can be mentioned.

  In the alicyclic hydrocarbon-based acid-decomposable resin according to the present invention, the group decomposed by the action of an acid has a partial structure containing the alicyclic hydrocarbon represented by the general formula (pI) to the general formula (pVI). It can be contained in at least one type of repeating unit among the repeating unit having, the repeating unit represented by the general formula (II-AB), and the repeating unit of the copolymerization component described later.

Various substituents of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or the general formula (II-B) are atomic groups for forming an alicyclic structure in the general formula (II-AB). It can also be a substituent of the atomic group Z for forming a bridged alicyclic structure. .

  Although the following specific examples are mentioned as a repeating unit represented by the said general formula (II-A) or general formula (II-B), This invention is not limited to these specific examples.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a lactone group and is represented by any one of the following general formula (Lc) or the following general formulas (V-1) to (V-5). It is more preferable to have a repeating unit having a group having a lactone structure. Further, a group having a lactone structure may be directly bonded to the main chain.

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ and Re ₁ each independently represents a hydrogen atom or an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.

In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring.

R _{1 to} Re ₁ alkyl groups in general formula (Lc) and R _{1b to} R _5b alkyl groups, alkoxy groups, alkoxycarbonyl groups, alkyl groups in general formulas (V-1) to (V-5) Examples of the alkyl group in the sulfonylimino group include linear and branched alkyl groups, which may have a substituent. Preferable substituents that may be included include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group, an acyloxy group, and a cycloalkyl group.

As the repeating unit having a group having a lactone structure represented by general formula (Lc) or any one of general formulas (V-1) to (V-5), the above general formula (II-A) or (II- B) wherein at least one of R ₁₃ ′ to R ₁₆ ′ has a group represented by general formula (Lc) or general formula (V-1) to (V-5) (for example, R in —COOR ₅ ) ₅ represents a group represented by general formula (Lc) or general formulas (V-1) to (V-5)), or a repeating unit represented by the following general formula (AI).

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. As a preferable substituent which the alkyl group of R _b0 may have, as a preferable substituent which the alkyl group as R _1b in the general formulas (V-1) to (V-5) may have. What was illustrated previously is mentioned.

Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R _b0 is preferably a hydrogen atom.

  A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.

B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

  Specific examples of the repeating unit having a group having a lactone structure are given below, but the present invention is not limited thereto.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention may contain a repeating unit having a group represented by the following general formula (VII) having an adamantane skeleton.

In general formula (VII), R _{2c to} R _4c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R _{2c to} R _4c represents a hydroxyl group.

  The group represented by the general formula (VII) is preferably a dihydroxy body or a monohydroxy body, and more preferably a dihydroxy body.

As the repeating unit having a group represented by the general formula (VII), at least one of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or (II-B) is the above general formula (VII ) (For example, R _{5 in} —COOR ₅ represents a group represented by the general formula (VII)), or a repeating unit represented by the following general formula (AII). it can.

In general formula (AII), R _1c represents a hydrogen atom or a methyl group.
R _{2c to} R _4c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R _{2c to} R _4c represents a hydroxyl group. Those in which two of R _{2c to} R _4c are hydroxyl groups are preferred.

  Specific examples of the repeating unit having the structure represented by the general formula (AII) are given below, but the present invention is not limited thereto.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention may contain a repeating unit represented by the following general formula (VIII).

In the general formula (VIII), Z ₂ represents —O— or —N (R ₄₁ ) —. R ₄₁ represents a hydrogen atom, a hydroxyl group, an alkyl group, or —OSO ₂ —R ₄₂ . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue. The alkyl group of R ₄₁ and R ₄₂ may be substituted with a halogen atom (preferably a fluorine atom) or the like.

  Examples of the repeating unit represented by the general formula (VIII) include the following specific examples, but the present invention is not limited thereto.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a repeating unit having an alkali-soluble group, and more preferably has a repeating unit having a carboxyl group. By containing this, the resolution in contact hole applications increases. The repeating unit having a carboxyl group includes a repeating unit in which a carboxyl group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or a carboxyl group in the main chain of the resin through a linking group. Any of the bonded repeating units is preferable, and the linking group may have a monocyclic or polycyclic hydrocarbon structure. Most preferred are acrylic acid and methacrylic acid.

  In addition to the above repeating structural units, the alicyclic hydrocarbon-based acid-decomposable resin of the present invention has a dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and resolving power that is a general necessary characteristic of a resist. Various repeating structural units can be contained for the purpose of adjusting heat resistance, sensitivity, and the like.

  Examples of such repeating structural units include, but are not limited to, repeating structural units corresponding to the following monomers.

  As a result, performance required for the alicyclic hydrocarbon-based acid-decomposable resin, in particular, (1) solubility in coating solvents, (2) film-forming properties (glass transition point), (3) alkali developability, (4 Fine adjustments such as :) film slippage (selection of hydrophilicity / hydrophobicity, alkali-soluble group), (5) adhesion of unexposed part to substrate, (6) dry etching resistance, etc. are possible.

  As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

  In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.

  In alicyclic hydrocarbon-based acid-decomposable resins, the molar ratio of each repeating structural unit is the resist's dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and resolution that is a general required performance of resists. In order to adjust heat resistance, sensitivity, etc., it is set appropriately.

Preferred embodiments of the alicyclic hydrocarbon-based acid-decomposable resin of the present invention include the following. (1) Containing a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the above general formulas (pI) to (pVI) (side chain type) (2) General formula (II-AB) Containing repeating units represented (main chain type)
However, in (2), for example, the following can be further mentioned. (3) A repeating unit represented by the general formula (II-AB), a maleic anhydride derivative and a (meth) acrylate structure (hybrid type)
In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit having an acid-decomposable group is preferably 10 to 60 mol%, more preferably 20 to 50 mol%, still more preferably 25 in all repeating structural units. -40 mol%.

  In the present invention, the repeating unit having an acid-decomposable group preferably contains at least one methacrylate repeating unit and at least one acrylic ester repeating unit. The molar ratio of acrylic acid ester to methacrylic acid ester is generally 10/90 to 90/10, preferably 20/80 to 80/20, more preferably 30/70 to 70/30, most preferably 40 / 60-60 / 40.

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit having a partial structure containing the alicyclic hydrocarbon represented by the general formulas (pI) to (pVI) is 30 to 70 in all the repeating structural units. The mol% is preferable, more preferably 35 to 65 mol%, and still more preferably 40 to 60 mol%.

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit represented by the general formula (II-AB) is preferably 10 to 60 mol%, more preferably 15 to 55 mol% in all repeating structural units. More preferably, it is 20-50 mol%.

  In addition, the content of the repeating structural unit based on the monomer of the further copolymer component in the resin can also be appropriately set according to the performance of the desired resist. 99 mol% with respect to the total number of moles of the repeating structural unit having a partial structure containing the alicyclic hydrocarbon represented by (pVI) and the repeating unit represented by the above general formula (II-AB) The following is preferable, More preferably, it is 90 mol% or less, More preferably, it is 80 mol% or less.

  When the composition of the present invention is for ArF exposure, the resin preferably has no aromatic group from the viewpoint of transparency to ArF light.

  The alicyclic hydrocarbon-based acid-decomposable resin used in the present invention can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, monomer species are charged into a reaction vessel in a batch or in the course of reaction, and if necessary, a reaction solvent such as ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, methyl ethyl ketone, A ketone such as methyl isobutyl ketone, an ester solvent such as ethyl acetate, and the composition of the present invention such as propylene glycol monomethyl ether acetate described below are dissolved in a solvent that dissolves uniformly and then nitrogen, argon, etc. Polymerization is started using a commercially available radical initiator (azo initiator, peroxide, etc.) as necessary under an inert gas atmosphere. If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery. The concentration of the reaction is 20% by mass or more, preferably 30% by mass or more, and more preferably 40% by mass or more. The reaction temperature is 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 50-100 ° C.

  When the composition of the present invention is used for the upper resist of the multilayer resist, the resin as the component (B) preferably has a silicon atom.

As the resin having a silicon atom and decomposing by the action of an acid to increase the solubility in an alkaline developer, a resin having a silicon atom in at least one of a main chain and a side chain can be used. Examples of the resin having a siloxane structure in the side chain of the resin include, for example, an olefin monomer having a silicon atom in the side chain, maleic anhydride and a (meth) acrylic acid monomer having an acid-decomposable group in the side chain. Mention may be made of copolymers.
As the resin having a silicon atom, a resin having a trialkylsilyl structure or a monocyclic or polycyclic siloxane structure is preferable, and a resin having a structure represented by the following general formulas (SS-1) to (SS-4) is used. The (meth) acrylic acid ester-based repeating unit, vinyl-based repeating unit or allyl-based repeating unit having a structure represented by the general formulas (SS-1) to (SS-4) is more preferable.

  In general formulas (SS-1) to (SS-4), Rs represents an alkyl group having 1 to 5 carbon atoms, preferably a methyl group or an ethyl group.

  The resin having a silicon atom preferably has a repeating unit having two or more different types of silicon atoms, more preferably (Sa) a repeating unit having 1 to 4 silicon atoms and (Sb) 5 to 10 silicon atoms. A resin having both of the repeating units, and more preferably, at least one repeating unit having a structure represented by formulas (SS-1) to (SS-3) and formula (SS-4). It is resin which has a repeating unit which has the structure represented by these.

When irradiating the positive photosensitive composition of the present invention with F ₂ excimer laser light, the resin of component (B) has a structure in which fluorine atoms are substituted on the main chain and / or side chains of the polymer skeleton, In addition, a resin that decomposes by the action of an acid and increases the solubility in an alkali developer (hereinafter also referred to as a fluorine group-containing resin) is preferable, and more preferably, a hydroxyl group substituted with a fluorine atom or a fluoroalkyl group at the 1-position or the 1-position Is a resin containing a group in which a hydroxyl group substituted with a fluorine atom or a fluoroalkyl group is protected with an acid-decomposable group, and most preferably the hexafluoro-2-propanol structure or the hydroxyl group of hexafluoro-2-propanol is protected with an acid-decomposable group The resin containing the structure. By introducing fluorine atoms, it is possible to improve transparency to far ultraviolet light, particularly F ₂ (157 nm) light.

  (B) Preferred examples of the fluorine group-containing resin in the acid-decomposable resin include resins having at least one repeating unit represented by the following general formulas (FA) to (FG).

In the general formula,
R _{100 to} R ₁₀₃ each represent a hydrogen atom, a fluorine atom, an alkyl group or an aryl group.
R ₁₀₄ and R ₁₀₆ are each a hydrogen atom, a fluorine atom or an alkyl group, and at least one of R ₁₀₄ and R ₁₀₆ is a fluorine atom or a fluoroalkyl group. R ₁₀₄ and R ₁₀₆ are preferably both trifluoromethyl groups.
R ₁₀₅ is a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an alkoxycarbonyl group or a group that decomposes under the action of an acid.
A ₁ is a single bond, a divalent linking group, for example, a linear, branched, cyclic alkylene group, alkenylene group, arylene group, —OCO—, —COO—, or —CON (R ₂₄ ) —, and of these It is a linking group containing a plurality. R ₂₄ is a hydrogen atom or an alkyl group.
R ₁₀₇ and R ₁₀₈ are each a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an alkoxycarbonyl group or a group that decomposes under the action of an acid.
R ₁₀₉ is a hydrogen atom, an alkyl group, a cycloalkyl group, or a group that decomposes under the action of an acid.
a is 0 or 1.
b is 0, 1 or 2;
R ₁₀₀ and R ₁₀₁ in the general formulas (FA) and (FC) may form a ring via an alkylene group (having 1 to 5 carbon atoms) which may be substituted with fluorine.

  The repeating units represented by the general formulas (FA) to (FG) contain at least one, preferably three or more fluorine atoms per one repeating unit.

  In the general formulas (FA) to (FG), the alkyl group is, for example, an alkyl group having 1 to 8 carbon atoms, specifically, a methyl group, an ethyl group, a propyl group, an n-butyl group, Preferred examples include sec-butyl group, hexyl group, 2-ethylhexyl group, and octyl group.

  The cycloalkyl group may be monocyclic or polycyclic. Preferred examples of the monocyclic type include those having 3 to 8 carbon atoms, such as cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group and cyclooctyl group. The polycyclic type has 6 to 20 carbon atoms, such as an adamantyl group, norbornyl group, isobornyl group, campanyl group, dicyclopentyl group, α-pinel group, tricyclodecanyl group, tetracyclododecyl group, An androstanyl group etc. can be mentioned preferably. However, the carbon atom in the monocyclic or polycyclic cycloalkyl group may be substituted with a heteroatom such as an oxygen atom.

  Examples of the fluoroalkyl group include those having 1 to 12 carbon atoms, specifically, a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluorohexyl group, and a perfluorooctyl group. A perfluorooctylethyl group, a perfluorododecyl group and the like can be preferably exemplified.

  As the aryl group, for example, an aryl group having 6 to 15 carbon atoms, specifically, phenyl group, tolyl group, dimethylphenyl group, 2,4,6-trimethylphenyl group, naphthyl group, anthryl group, Preferable examples include 9,10-dimethoxyanthryl group.

  Examples of the alkoxy group include an alkoxy group having 1 to 8 carbon atoms, and specifically include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, a butoxy group, a pentoxy group, an allyloxy group, and an octoxy group. Preferred examples include groups.

  As the acyl group, for example, an acyl group having 1 to 10 carbon atoms, specifically, a formyl group, an acetyl group, a propanoyl group, a butanoyl group, a pivaloyl group, an octanoyl group, a benzoyl group and the like can be preferably exemplified. it can.

  Examples of the alkoxycarbonyl group include i-propoxycarbonyl group, t-butoxycarbonyl group, t-amyloxycarbonyl group, 1-methyl-1-cyclohexyloxycarbonyl group and the like, preferably secondary, more preferably tertiary alkoxycarbonyl. Groups.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  The alkylene group is preferably an alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group and an octylene group.

  The alkenylene group is preferably an alkenylene group having 2 to 6 carbon atoms such as an ethenylene group, a propenylene group, or a butenylene group.

  Preferred examples of the cycloalkylene group include those having 5 to 8 carbon atoms such as a cyclopentylene group and a cyclohexylene group.

  The arylene group is preferably an arylene group having 6 to 15 carbon atoms such as a phenylene group, a tolylene group and a naphthylene group.

  In addition, these groups may have a substituent, and examples of the substituent include activities such as alkyl group, cycloalkyl group, aryl group, amino group, amide group, ureido group, urethane group, hydroxyl group, and carboxy group. Those having hydrogen, halogen atoms (fluorine atom, chlorine atom, bromine atom, iodine atom), alkoxy groups (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), thioether group, acyl group (acetyl group, propanoyl group) Benzoyl group, etc.), acyloxy group (acetoxy group, propanoyloxy group, benzoyloxy group etc.), alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group etc.), cyano group, nitro group, etc. .

  Here, examples of the alkyl group, cycloalkyl group, and aryl group include those described above, but the alkyl group may be further substituted with a fluorine atom or a cycloalkyl group.

Fluorine-containing are contained in the resin of the present invention, examples of the group in a disassembled alkali solubility by the action of an acid, for example, _{-O-C (R 36) (} R 37) (R 38), - O-C (R 36 ) (R ₃₇ ) (OR ₃₉ ), —O—COO—C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), —O—C (R ₀₁ ) (R ₀₂ ) COO—C (R ₃₆ ) (R _{37) (R 38), -} COO-C (R 36) (R 37) (R 38), - COO-C (R 36) (R 37) (OR 39) , and the like.

R _{36 to} R ₃₉ represent an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group, and R ₀₁ and R ₀₂ are a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group (vinyl group, allyl group). , Butenyl group, cyclohexenyl group, etc.), aralkyl group (benzyl group, phenethyl group, naphthylmethyl group, etc.) or aryl group.

  Preferable specific examples include t-butyl group, t-amyl group, 1-alkyl-1-cyclohexyl group, 2-alkyl-2-adamantyl group, 2-adamantyl-2-propyl group, 2- (4-methylcyclohexyl). ) Ether group or ester group of tertiary alkyl group such as 2-propyl group, acetal group or acetal ester group such as 1-alkoxy-1-ethoxy group, tetrahydropyranyl group, t-alkyl carbonate group, t-alkyl A carbonylmethoxy group etc. are mentioned preferably.

  Specific examples of the repeating structural units represented by the general formulas (FA) to (FG) are shown below, but the present invention is not limited thereto.

  The total content of the repeating units represented by formulas (FA) to (FG) is generally 10 to 80 mol%, preferably 30 to 70 mol%, more preferably based on all repeating units constituting the resin. Is used in the range of 35 to 65 mol%.

  The resin of the present invention (B) may be copolymerized with other polymerizable monomers for the purpose of further improving the performance of the resist of the present invention in addition to the above repeating structural units.

  Examples of copolymerizable monomers that can be used include those shown below. For example, an addition polymerizable unsaturated bond selected from acrylic acid esters, acrylamides, methacrylic acid esters, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, styrenes, crotonic acid esters other than the above. A compound having one.

Such a fluorine group-containing resin contains other repeating units as a copolymerization component in addition to the repeating unit having fluorine atoms, from the viewpoints of improving dry etching resistance, adjusting alkali solubility, and improving substrate adhesion. Is preferred. Preferred as other repeating units are:
1) A repeating unit having an alicyclic hydrocarbon structure represented by the general formulas (pI) to (pVI) and (II-AB). Specifically, the repeating units 1 to 23 and the repeating units [II-1] to [II-32]. Of the above specific examples 1 to 23, Rx is preferably CF ₃ .

  2) A repeating unit having a lactone structure represented by the general formulas (Lc) and (V-1) to (V-5). Specifically, the repeating units exemplified above, particularly the repeating units having the groups represented by the general formulas (Lc) and (V-1) to (V-4) exemplified above.

  3) The following general formula (XV) (XVI) (XVII) derived from a maleic anhydride, vinyl ether or a vinyl compound having a cyano group, specifically the repetitions listed in (C-1) to (C-15) Units are listed. These other repeating units may or may not contain a fluorine atom.

In the formula, R ₄₁ represents an alkyl group, a cycloalkyl group, an aralkyl group or an aryl group. The alkyl group of R ₄₁ may be substituted with an aryl group.
R ₄₂ represents a hydrogen atom, a halogen atom, a cyano group or an alkyl group.
A ₅ is a single bond, a divalent alkylene group, an alkenylene group, a cycloalkylene group or an arylene group, or —O—CO—R ₂₂ —, —CO—O—R ₂₃ —, —CO—N (R ₂₄ ) —. R ₂₅ -is represented.
R ₂₂ , R ₂₃ and R ₂₅ may be the same or different and each may have a single bond, an ether group, an ester group, an amide group, a urethane group or a ureido group, a divalent alkylene group, an alkenylene group Represents a cycloalkylene group or an arylene group.
R ₂₄ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aralkyl group or an aryl group.
Here, examples of each substituent include those similar to the substituents of the general formulas (FA) to (FG).

  Specific examples of the repeating structural units represented by the general formulas (XV) to (XVII) are shown below, but the present invention is not limited thereto.

  The total amount of the repeating units represented by the general formulas (XV) to (XVII) and other repeating units is generally 0 to 70 mol%, preferably 10 to 60 mol%, based on all repeating units constituting the resin. More preferably, it is used in the range of 20 to 50 mol%.

(B) The fluorine group-containing resin as the acid-decomposable resin may contain an acid-decomposable group in any repeating unit.
As for content of the repeating unit which has an acid-decomposable group, 10-70 mol% is preferable with respect to all the repeating units, More preferably, it is 20-60 mol%, More preferably, it is 30-60 mol%.

  The fluorine group-containing resin can be synthesized by radical polymerization in substantially the same manner as the alicyclic hydrocarbon-based acid-decomposable resin.

  The weight average molecular weight of the resin of the component (B) according to the present invention is preferably 1,000 to 200,000 as a polystyrene conversion value by the GPC method. By making the weight average molecular weight 1,000 or more, heat resistance and dry etching resistance can be improved, and by making the weight average molecular weight 200,000 or less, developability can be improved. In addition, since the viscosity is extremely low, the film forming property can be improved.

  In the positive photosensitive composition of the present invention, the blending amount of the resin of the component (B) according to the present invention in the entire composition is preferably 40 to 99.99% by mass in the total solid content, more preferably 50 to 50%. It is 99.97 mass%.

[3] (C) Dissolution-inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as “(C) component” or “dissolution-inhibiting compound”) that is decomposed by the action of an acid to increase the solubility in an alkaline developer.
(C) As a dissolution inhibiting compound having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer, the permeability of 220 nm or less is not reduced. Proceeding of SPIE, 2724,355 (1996) Preference is given to alicyclic or aliphatic compounds containing acid-decomposable groups, such as the cholic acid derivatives containing acid-decomposable groups described. Examples of the acid-decomposable group and alicyclic structure are the same as those described above for the alicyclic hydrocarbon-based acid-decomposable resin.

  When exposing the photosensitive composition of this invention with a KrF excimer laser, or irradiating with an electron beam, what contains the structure which substituted the phenolic hydroxyl group of the phenol compound by the acid-decomposable group is preferable. As a phenol compound, what contains 1-9 phenol frame | skeleton is preferable, More preferably, it contains 2-6 pieces.

  The molecular weight of the dissolution inhibiting compound in the present invention is 3000 or less, preferably 300 to 3000, and more preferably 500 to 2500.

  The addition amount of the dissolution inhibiting compound is preferably 3 to 50% by mass, more preferably 5 to 40% by mass, based on the solid content of the photosensitive composition.

  Specific examples of the dissolution inhibiting compound are shown below, but the present invention is not limited thereto.

[4] (D) Resin soluble in alkali developer (hereinafter also referred to as “component (D)” or “alkali-soluble resin”)
The alkali dissolution rate of the alkali-soluble resin is preferably 20 A / second or more as measured with 0.261N tetramethylammonium hydroxide (TMAH) (23 ° C.). Particularly preferably, it is 200 A / second or more (A is angstrom).

  Examples of the alkali-soluble resin used in the present invention include novolak resin, hydrogenated novolak resin, acetone-pyrogalol resin, o-polyhydroxystyrene, m-polyhydroxystyrene, p-polyhydroxystyrene, hydrogenated polyhydroxystyrene, and halogen. Alternatively, alkyl-substituted polyhydroxystyrene, hydroxystyrene-N-substituted maleimide copolymer, o / p- and m / p-hydroxystyrene copolymer, partially O-alkylated product of hydroxyl group of polyhydroxystyrene (for example, 5- 30 mol% O-methylated product, O- (1-methoxy) ethylated product, O- (1-ethoxy) ethylated product, O-2-tetrahydropyranylated product, O- (t-butoxycarbonyl) methylated product, etc.) Or O-acylated product (for example, 5 to 30 mol) O-acetylated product, O- (t-butoxy) carbonylated product, etc.), styrene-maleic anhydride copolymer, styrene-hydroxystyrene copolymer, α-methylstyrene-hydroxystyrene copolymer, carboxyl group-containing methacrylic acid Examples thereof include, but are not limited to, resins and derivatives thereof, and polyvinyl alcohol derivatives.

  Particularly preferred alkali-soluble resins are novolak resins and o-polyhydroxystyrene, m-polyhydroxystyrene, p-polyhydroxystyrene and copolymers thereof, alkyl-substituted polyhydroxystyrenes, partially O-alkylated polyhydroxystyrenes, Alternatively, O-acylated product, styrene-hydroxystyrene copolymer, and α-methylstyrene-hydroxystyrene copolymer.

  The novolak resin is obtained by subjecting a predetermined monomer as a main component to addition condensation with an aldehyde in the presence of an acidic catalyst.

  Moreover, the weight average molecular weight of alkali-soluble resin is 2000 or more, Preferably it is 5000-200000, More preferably, it is 5000-100000.

  Here, the weight average molecular weight is defined as a polystyrene equivalent value of gel permeation chromatography.

  These (D) alkali-soluble resins in the present invention may be used in combination of two or more.

  The usage-amount of alkali-soluble resin is 40-97 mass% with respect to solid content of the whole composition of a photosensitive composition, Preferably it is 60-90 mass%.

[5] (E) Acid crosslinking agent that crosslinks with the alkali-soluble resin by the action of acid (hereinafter also referred to as “(E) component” or “crosslinking agent”)
A crosslinking agent is used in the negative photosensitive composition of the present invention.

  As the cross-linking agent, any compound that cross-links a resin soluble in an alkali developer by the action of an acid can be used, but the following (1) to (3) are preferable. (1) Hydroxymethyl, alkoxymethyl, and acyloxymethyl forms of phenol derivatives. (2) A compound having an N-hydroxymethyl group, an N-alkoxymethyl group, or an N-acyloxymethyl group. (3) A compound having an epoxy group.

  The alkoxymethyl group preferably has 6 or less carbon atoms, and the acyloxymethyl group preferably has 6 or less carbon atoms.

  Of these crosslinking agents, particularly preferred are listed below.

In the formula, L ^{1 to} L ⁸ may be the same or different and each represents a hydrogen atom, a hydroxymethyl group, a methoxymethyl group, an ethoxymethyl group, or an alkyl group having 1 to 6 carbon atoms.
The crosslinking agent is generally used in an amount of 3 to 70% by mass, preferably 5 to 50% by mass, in the solid content of the photosensitive composition.

<Other ingredients>
[6] (F) Basic compound The photosensitive composition of the present invention preferably contains (F) a basic compound in order to reduce a change in performance over time from exposure to heating.

  Preferable structures include structures represented by the following formulas (A) to (E).

Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, And R ²⁵⁰ and R ²⁵¹ may combine with each other to form a ring. These may have a substituent. Examples of the alkyl group and cycloalkyl group having a substituent include an aminoalkyl group having 1 to 20 carbon atoms, an aminocycloalkyl group having 3 to 20 carbon atoms, and 1 to 1 carbon atoms. A 20 hydroxyalkyl group or a C 3-20 hydroxycycloalkyl group is preferred.
These may contain an oxygen atom, a sulfur atom, or a nitrogen atom in the alkyl chain.

In the formula, R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ each independently represent an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms.

  Preferable compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, and piperidine, which have a substituent and BR> 烽 謔. , Diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, trialkylamine structure, aniline structure or pyridine structure compound, alkylamine derivative having hydroxyl group and / or ether bond, aniline derivative having hydroxyl group and / or ether bond Etc.

  Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole, and the like. Examples of the compound having a diazabicyclo structure include 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] non-5-ene, and 1,8-diazabicyclo [5,4,0. ] Undec-7-ene. Examples of the compound having an onium hydroxide structure include triarylsulfonium hydroxide, phenacylsulfonium hydroxide, sulfonium hydroxide having a 2-oxoalkyl group, specifically triphenylsulfonium hydroxide, tris (t-butylphenyl) sulfonium. Examples thereof include hydroxide, bis (t-butylphenyl) iodonium hydroxide, phenacylthiophenium hydroxide, and 2-oxopropylthiophenium hydroxide. The compound having an onium carboxylate structure is a compound having an onium hydroxide structure in which the anion moiety is converted to a carboxylate, and examples thereof include acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine and tri (n-octyl) amine. Examples of aniline compounds include 2,6-diisopropylaniline and N, N-dimethylaniline. Examples of the alkylamine derivative having a hydroxyl group and / or an ether bond include ethanolamine, diethanolamine, triethanolamine, and tris (methoxyethoxyethyl) amine. Examples of aniline derivatives having a hydroxyl group and / or an ether bond include N, N-bis (hydroxyethyl) aniline.

  These basic compounds are used alone or in combination of two or more. The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of solid content of a photosensitive composition, Preferably it is 0.01-5 mass%. In order to obtain a sufficient addition effect, 0.001% by mass or more is preferable, and 10% by mass or less is preferable in terms of sensitivity and developability of the non-exposed area.

[7] (G) Fluorine-based and / or silicon-based surfactant The photosensitive composition of the present invention further includes a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant and silicon-based surfactant, It is preferable to contain any one of surfactants containing both fluorine atoms and silicon atoms, or two or more thereof.

  When the photosensitive composition of the present invention contains fluorine and / or a silicon-based surfactant, adhesion and development defects can be obtained with good sensitivity and resolution when using an exposure light source of 250 nm or less, particularly 220 nm or less. A small resist pattern can be provided.

  Examples of these fluorine and / or silicon surfactants include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.

  Examples of commercially available surfactants that can be used include EFTOP EF301 and EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430 and 431 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189, and R08. (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical Co., Ltd.), etc. Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

  In addition to the known surfactants described above, the surfactant is derived from a fluoroaliphatic compound produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.

  As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. It may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy) (Ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate) copolymer, acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate having C ₈ F ₁₇ groups (or Copolymer of acrylate (or methacrylate), (poly (oxyethylene)) acrylate (or methacrylate), and (poly (oxypropylene)) acrylate (or methacrylate) having a C ₈ F ₁₇ group Coalesce, etc. Can.

  The amount of fluorine and / or silicon surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total amount of the photosensitive composition (excluding the solvent). is there.

[8] (H) Organic solvent The photosensitive composition of the present invention is used by dissolving the above components in a predetermined organic solvent.

  Examples of the organic solvent that can be used include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl. Ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N -Dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, etc.

  In the present invention, the organic solvent may be used alone or in combination, but it is preferable to use a mixed solvent in which a solvent containing a hydroxyl group in the structure and a solvent not containing a hydroxyl group are mixed. . Thereby, the generation of particles during storage of the resist solution can be reduced.

  Examples of the solvent containing a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Particularly preferred are propylene glycol monomethyl ether and ethyl lactate.

  Examples of the solvent not containing a hydroxyl group include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, and butyl acetate are particularly preferred, and propylene glycol monomethyl ether acetate, ethyl ethoxypropionate. 2-heptanone is most preferred.

  The mixing ratio (mass) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60/40. . A mixed solvent containing 50% by mass or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.

<Other additives>
If necessary, the photosensitive composition of the present invention further contains a dye, a plasticizer, a surfactant other than the component (G), a photosensitizer, a compound that promotes solubility in a developer, and the like. be able to.

  The dissolution accelerating compound for the developer that can be used in the present invention is a low molecular weight compound having a molecular weight of 1,000 or less and having two or more phenolic OH groups or one or more carboxy groups. When it has a carboxy group, an alicyclic or aliphatic compound is preferable.

  A preferable addition amount of these dissolution promoting compounds is 2 to 50% by mass, and more preferably 5 to 30% by mass with respect to the resin of the component (B) or the resin of the component (D). 50 mass% or less is preferable at the point of development residue suppression and the pattern deformation prevention at the time of image development.

  Such phenolic compounds having a molecular weight of 1000 or less can be obtained by referring to methods described in, for example, JP-A-4-1222938, JP-A-2-28531, U.S. Pat. No. 4,916,210, European Patent 219294, and the like. Can be easily synthesized.

  Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples thereof include, but are not limited to, dicarboxylic acids.

  In the present invention, a surfactant other than the above (G) fluorine-based and / or silicon-based surfactant may be added. Specifically, nonionic interfaces such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan aliphatic esters, polyoxyethylene sorbitan aliphatic esters, etc. Mention may be made of activators.

  These surfactants may be added alone or in some combination.

(how to use)
The photosensitive composition of the present invention is used by dissolving the above components in a predetermined organic solvent, preferably the mixed solvent, and applying the solution on a predetermined support as follows.

For example, the photosensitive composition is applied onto a substrate (eg, silicon / silicon dioxide coating) used for the manufacture of precision integrated circuit elements by an appropriate coating method such as a spinner or a coater, and dried to form a photosensitive film. Form.
The photosensitive film is irradiated with actinic rays or radiation through a predetermined mask, preferably baked (heated), and developed and rinsed. Thereby, a good pattern can be obtained.

Examples of the actinic ray or radiation include infrared light, visible light, ultraviolet light, far ultraviolet light, X-ray, electron beam, etc., but preferably far ultraviolet light having a wavelength of 250 nm or less, more preferably 220 nm or less. Specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-ray, electron beam, etc. ArF excimer laser, F ₂ excimer laser, EUV (13 nm) An electron beam is preferred.

  In the development step, an alkaline developer is used as follows. As an alkaline developer of the resist composition, inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, Secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like Alkaline aqueous solutions such as quaternary ammonium salts, cyclic amines such as pyrrole and pihelidine can be used.

  Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.

The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.

EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, the content of this invention is not limited by this.
Examples Ar15, KrP-8, KrN-1 to 21, EBP-8, EBN-1 to 21, EUVP-8, EUUV-1 to 21 are reference examples.

<Synthesis Example 1 Synthesis of 10-Tolyl-9-oxothioxanthenium nonafluorobutanesulfonate (A1)>
10 g of thioxanthen-9-one was stirred in 40 ml of trifluoroacetic acid, and a solution prepared by mixing 5.4 ml of 30% aqueous hydrogen peroxide and 10.8 ml of trifluoroacetic acid was slowly added under ice cooling. Thereafter, the mixture was stirred for 30 minutes under ice cooling, and then stirred at room temperature for 1 hour. Further, the reaction solution was poured into water, and the precipitated crystals were collected by filtration. The obtained crystals were recrystallized from acetonitrile to obtain 4.6 g of a sulfoxide form. 3 g of the sulfoxide compound was stirred in 20 ml of toluene, and 3.7 ml of trifluoroacetic anhydride and 2.2 ml of nonafluorobutanesulfonic acid were added under ice cooling. The reaction was gradually warmed to room temperature and stirred for 1 hour. Diisopropyl ether was added to the reaction solution to precipitate crystals, which were recrystallized with a mixed solvent of ethyl acetate and diisopropyl ether to give 10-tolyl-9-oxothioxanthenium nonafluorobutanesulfonate (A1) 3 .9 g was obtained. ¹ H-NMR (400 MHz, CDCl3) σ 2.38 (s, 3H), 7.34 (d, 2H), 7.72 (m, 2H), 7.95 (m, 4H), 8.28 (m, 2H), 8.63 (d, 2H)

<Synthesis Example 2 Synthesis of 10-tolyl-9-oxothioxanthenium 3,5-bistrifluoromethylbenzenesulfonate (A2)>
To 1.5 g of 10-tolyl-9-oxothioxanthenium nonafluorobutanesulfonate (A1) obtained in Synthesis Example 1, 10-tolyl-9-oxothioxanthenium nonafluorobutanesulfonate 1 .5 g is dissolved in a methanol / water = 1/1 solution, passed through an ion exchange resin (Amberlite IRA402Cl in which anion is replaced with OH with NaOH water), and 1 g of 3,5-bistrifluoromethylbenzenesulfonic acid is added. Then, 1.7 g of 10-tolyl-9-oxothioxanthenium 3,5-bistrifluoromethylbenzenesulfonate (A2) whose counter salt was changed by extraction with chloroform was obtained. ¹ H-NMR (400 MHz, CDCl 3) σ2.37 (s, 3H), 7.34 (d, 2H), 7.79 (m, 3H), 7.93 (m, 4H), 8.34 (m, 4H), 8.62 (d, 2H)

<Synthesis Example 3 Synthesis of 2-acetyl-10-tolyl-9-oxothioxanthenium nonafluorobutanesulfonate (A8)>
15 g of thiosalicylic acid and 20 g of 4-bromoacetophenone were stirred in 170 ml of dimethylformamide in the presence of 12 g of sodium carbonate and 0.2 g of copper catalyst for 6 hours at 170 ° C. Then, the reaction solution was poured into an aqueous hydrochloric acid solution and collected by filtration. The obtained crystals were recrystallized from acetonitrile to obtain 16 g of sulfide. 10 g of the obtained sulfide was stirred in 60 g of polyphosphoric acid at 60 degrees for 5 hours, and then poured into ice water. The crystals were collected by filtration, washed with an aqueous sodium hydrogen carbonate solution and water, and recrystallized with ethanol to obtain 5 g of 2-acetyl-9H-thioxan-9-one. Further, 3 g of the obtained 2-acetyl-9H-thioxan-9-one was stirred in 12 ml of trifluoroacetic acid under ice cooling, and a mixed solution of 1.4 ml of 30% hydrogen peroxide and 2.7 ml of trifluoroacetic acid was slowly added. added. After the addition, the mixture was stirred for 30 minutes under ice cooling, followed by stirring at room temperature for 1 hour to complete the reaction. The reaction solution was poured into water, and separated with ethyl acetate and an aqueous sodium hydroxide solution, and the organic layer was distilled off under reduced pressure to obtain 3.6 g of a sulfoxide form. The mixture was stirred in 15 g of toluene, 3.3 ml of trifluoroacetic anhydride and 1.9 ml of nonafluorobutanesulfonic acid were added under ice cooling, and the mixture was stirred for 30 minutes under ice cooling and at room temperature for 1 hour. Diisopropyl ether is added to the reaction solution for crystallization, and the resulting crystal is recrystallized with a mixed solvent of ethyl acetate and diisopropyl ether to give 2-acetyl-10-tolyl-9-oxothioxanthenium nonafluorobutanesulfonic acid. 1 g of salt (A8) was obtained. ¹ H-NMR (400 MHz, CDCl3) σ 2.39 (s, 3H), 2.74 (s, 3H), 7.37 (d, 2H), 7.72 (m, 2H), 7.97 (m, 2H), 8.19 (m, 1H), 8.39 (m, 2H), 8.67 (d, 1H), 9.09 (s, 1H)
Other sulfonium salts (A) were synthesized in the same manner.

<Synthesis of Synthesis Example 4 (A40)>
20 g of thianthrene was refluxed in 300 ml of acetic acid, and 36 ml of diluted nitric acid was slowly added dropwise thereto. After reacting for 5 hours, the reaction solution was poured into 1.2 l of water to precipitate crystals. The crystals were filtered and recrystallized from acetonitrile to obtain 12 g of thianslene-S-oxide. ¹ H-NMR (400MHz, CDCl3) σ7.42 (t, 2H), 7.56 (t, 2H), 7.63 (d, 2H), 7.93 (d, 2H)
Thianthrene-S-oxide (2 g) was dissolved in 10 ml of toluene and cooled on ice. Thereto, 2.8 ml of trifluoroacetic anhydride and 1.2 ml of nonafluorobutanesulfonic acid were added and stirred for 1 hour. Diisopropyl ether was added and the supernatant was removed, followed by purification with a silica gel column (chloroform / methanol = 19/1) to obtain 4.4 g of 5- (p-tolyl) thianthrenium nonafluorobutanesulfonate. ¹ H-NMR (400 MHz, CDCl3) σ 2.34 (s, 3H), 7.08 (d, 2H), 7.22 (d, 2H), 7.78 (m, 6H), 8.65 (d, 2H)
2 g of 5- (p-tolyl) thianthrenium nonafluorobutanesulfonate was suspended in 6 ml of trifluoroacetic acid, and 0.75 ml of 30% aqueous hydrogen peroxide was added dropwise at room temperature. Then, it stirred at 80 degreeC for 1 hour, water and chloroform were added and liquid separation was performed. After the chloroform layer was distilled off under reduced pressure, purification was performed with a silica gel column (chloroform / methanol = 19/1) to obtain 1.2 g of (A40). ¹ H-NMR (400 MHz, CDCl 3) σ 2.47 (s, 3H), 7.47 (d, 2H), 7.66 (d, 2H), 7.98 (t, 2H), 8.04 (t, 2H), 8.40 (d, 2H), 8.43 (d, 2H)

<Synthesis of Synthesis Example 5 (A73)>
1 g of thianslene-S-oxide was mixed with 1.1 ml of ethoxybenzene and cooled on ice. Thereto were added 1.2 ml of trifluoroacetic anhydride and 0.71 ml of nonafluorobutanesulfonic acid, and the mixture was stirred for 15 minutes. Diisopropyl ether was added and the supernatant was removed, followed by separation with chloroform and water. The chloroform layer was distilled off under reduced pressure to obtain 2.5 g of 5- (p-ethoxybenzene) thianthrenium nonafluorobutanesulfonate. ¹ H-NMR (400 MHz, CDCl3) σ 1.38 (t, 3H), 4.00 (q, 2H), 6.92 (d, 2H), 7.29 (d, 2H), 7.75 (m, 6H), 8.56 (d, 2H)
2.5 g of 5- (p-ethoxybenzene) thianthrenium nonafluorobutanesulfonate was suspended in 10 ml of trifluoroacetic acid and cooled on ice. Thereto was added dropwise 0.89 ml of 30% hydrogen peroxide and stirred for 1 hour. After the reaction, the reaction solution was poured into water, and further chloroform was added for liquid separation. The chloroform layer was distilled off under reduced pressure, and recrystallization was performed with a mixed solvent of diisopropyl ether and ethyl acetate to obtain 1.3 g of (A73). ¹ H-NMR (400 MHz, CDCl 3) σ 1.47 (t, 3H), 4.20 (q, 2H), 7.26 (d, 2H), 7.91 (m, 6H), 7.98 (m, 2H), 8.39 (d, 2H)

<Resin (B)>
The structure and weight average molecular weight of the resin (B) used in the examples are shown below.

[Examples Ar1 to Ar33 and Comparative Examples ar1 and ar2]

<Resist preparation>
The components shown in Table 1 below were dissolved in a solvent to prepare a solution having a solid content concentration of 12% by mass, and this was filtered through a 0.1 μm polytetrafluoroethylene filter or a polyethylene filter to prepare a positive resist solution. The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 1.

<Resist evaluation>
An anti-reflective coating DUV-42 manufactured by Brewer Science Co., Ltd. was uniformly applied to 600 angstroms on a silicon substrate subjected to hexamethyldisilazane treatment with a spin coater, dried on a hot plate at 100 ° C. for 90 seconds, and then at 190 ° C. Heat drying was performed for 240 seconds. Thereafter, each positive resist solution was applied by a spin coater and dried at 120 ° C. for 90 seconds to form a 0.30 μm resist film.
The resist film was exposed with an ArF excimer laser stepper (NA = 0.6 manufactured by ISI) through a mask, and immediately after the exposure, it was heated on a hot plate at 120 ° C. for 90 seconds. Further, the resist film was developed with an aqueous 2.38 mass% tetramethylammonium hydroxide solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and then dried to obtain a line pattern. (Sensitivity) Sensitivity was expressed by an exposure amount for reproducing a line and space 1: 1 pattern having a line width of 130 nm.

  Abbreviations common to Table 1 and Tables 2, 3, 5, and 6 below are summarized below.

[Acid generator]
PAG-A: Triphenylsulfonium nonafluorobutane sulfonate

[Basic compounds]
TPI: 2,4,5-triphenylimidazole TPSA: triphenylsulfonium acetate HEP: N-hydroxyethylpiperidine DIA: 2,6-diisopropylaniline DCMA: dicyclohexylmethylamine TPA: tripentylamine HAP: hydroxyantipyrine TBAH: tetrabutyl Ammonium hydroxide TMEA: Tris (methoxyethoxyethyl) amine PEA: N-phenyldiethanolamine

[Surfactant]
W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)
W-4: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)

〔solvent〕
B1: Propylene glycol monomethyl ether acetate B2: 2-heptanone B3: Cyclohexanone B4: γ-butyrolactone B5: Ethyl 2-methoxypropionate C1: Propylene glycol methyl ether C2: Ethyl lactate

  From the results in Table 1, it is clear that the sensitivity of the photosensitive composition of the present invention is excellent in ArF exposure.

[Examples Si-1 to Si-9 and comparative examples si-1 and si-2]
(1) Formation of lower resist layer FHi-028DD resist (resist for i-line manufactured by Fuji Film Orin) was applied to a 6-inch silicon wafer using a spin coater Mark8 manufactured by Tokyo Electron, and baked at 90 ° C. for 90 seconds to form a film. A uniform film having a thickness of 0.55 μm was obtained.
This was further heated at 200 ° C. for 3 minutes to form a lower resist layer having a thickness of 0.40 μm.
(2) Formation of the upper resist layer The components shown in Table 2 below are dissolved in a solvent to prepare a solution having a solid content of 11% by mass, and the solution is precisely filtered through a membrane filter having a diameter of 0.1 μm to prepare an upper resist composition. did.
The upper resist composition was similarly applied onto the lower resist layer and heated at 130 ° C. for 90 seconds to form an upper resist layer having a thickness of 0.20 μm.

  Resins (SI-1) to (SI-5) in Table 2 are as follows.

(3) Resist Evaluation The wafer thus obtained was exposed while changing the exposure amount by loading a resolution mask on an ArF excimer stepper 9300 manufactured by ISI.
Subsequently, after heating at 120 ° C. for 90 seconds, the film was developed with a tetrahydroammonium hydroxide developer (2.38 mass%) for 60 seconds, rinsed with distilled water, and dried to obtain an upper layer pattern. (Sensitivity) Sensitivity was expressed by an exposure amount for reproducing a line and space 1: 1 pattern having a line width of 130 nm.

  The results are shown in Table 2.

  From the results in Table 2, it is clear that the photosensitive composition of the present invention has excellent sensitivity even when used as a two-layer resist.

[Examples KrP-1 to KrP-31 and Comparative Examples krp-1 and krp-2]
<Resist preparation>
The components shown in Table 4 below were dissolved in a solvent and filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a positive resist solution having a solid content concentration of 14% by mass.
The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 4.

  Table 3 below shows the molar ratios and weight average molecular weights of the resins (R-2) to (R-86) in Table 4. The repeating units constituting the resins (R-2) to (R-86) are those exemplified above.

<Resist evaluation>
The prepared positive resist solution is uniformly coated on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 90 seconds to obtain a 0.4 μm resist. A film was formed.
The resist film was subjected to pattern exposure using a line and space mask using a KrF excimer laser stepper (NA = 0.63), and heated on a hot plate at 110 ° C. for 90 seconds immediately after the exposure. Further, the resist film was developed with an aqueous 2.38 mass% tetramethylammonium hydroxide solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, dried, a line pattern was formed, and the sensitivity was evaluated.
Sensitivity: Sensitivity was expressed by an exposure amount that reproduces a line-and-space 1: 1 pattern having a line width of 150 nm.

  The evaluation results are shown in Table 4.

  From the results in Table 4, it is clear that the photosensitive composition of the present invention has excellent sensitivity even as a positive resist composition in KrF excimer laser exposure.

[Examples KrN-1 to KrN-21 and Comparative Examples krn-1 and krn-2]
<Resist preparation>
The components shown in Table 5 below were dissolved in a solvent, and this was filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a negative resist solution having a solid concentration of 14% by mass.
The prepared negative resist solution was evaluated in the same manner as in Examples KrP-1 to KrP-13 and the results are shown in Table 5.

  The structure, molecular weight, and molecular weight distribution of the alkali-soluble resin in Table 5 are shown below.

  The structure of the crosslinking agent in Table 5 is shown below.

From the results in Table 5, it is clear that the photosensitive composition of the present invention is excellent in sensitivity even as a negative resist composition in KrF excimer laser exposure.

[Examples EBP-1 to EBP-31 and Comparative Examples ebp-1 and ebp-2]
<Resist preparation>
The components shown in Table 4 were dissolved in a solvent, and this was filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a positive resist solution having a solid content concentration of 12% by mass.
The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 6.

<Resist evaluation>
The prepared positive resist solution is uniformly applied on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 60 seconds to obtain a 0.3 μm resist. A film was formed.
This resist film was irradiated with an electron beam projection lithography apparatus (acceleration voltage 100 keV) manufactured by Nikon Corporation, and immediately after the irradiation, it was heated on a hot plate at 110 ° C. for 90 seconds. Further, development was performed at 23 ° C. for 60 seconds using an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass, rinsed with pure water for 30 seconds, and then dried to form a line and space pattern. Sensitivity: Sensitivity was expressed by the dose that reproduces the line and space 1: 1 of the mask pattern 100 nm.
Outgas: Irradiated at 10 μC / cm ² , the film thickness after irradiation with respect to the film thickness before irradiation was measured and evaluated as the amount of outgas.

  From the results of Table 6, it is clear that the photosensitive composition of the present invention is excellent in high sensitivity, low outgas, and excellent as a positive resist composition in electron beam irradiation.

[Examples EBN-1 to EBN-21 and Comparative Examples ebn-1 and ebn-2]
<Resist preparation>
The components shown in Table 5 above were dissolved in a solvent, which was filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a negative resist solution having a solid content concentration of 12% by mass.
The prepared negative resist solution was evaluated by the following method, and the results are shown in Table 7.

<Resist evaluation>
The prepared negative resist solution is uniformly applied on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 60 seconds to obtain a 0.3 μm resist. A film was formed.
This resist film was irradiated with an electron beam projection lithography apparatus (acceleration voltage 100 keV) manufactured by Nikon Corporation, and immediately after the irradiation, it was heated on a hot plate at 110 ° C. for 90 seconds. Further, development was performed at 23 ° C. for 60 seconds using an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass, rinsed with pure water for 30 seconds, and then dried to form a line and space pattern.
Sensitivity: Sensitivity was expressed by the dose that reproduces the mask pattern 100 nm line / 150 nm space.
Outgas: Irradiated at 10 μC / cm ² , the film thickness after irradiation when compared with before irradiation was measured and evaluated as the amount of outgas.

  From the results of Table 7, it is clear that the photosensitive composition of the present invention is excellent in high sensitivity, low outgas, and excellent as a negative resist composition in electron beam irradiation.

[Examples EUVP-1 to EUVP-31 and Comparative Example euvp-1 · euvp-2] [Pattern Production and Evaluation (EUV)]
The components shown in Table 4 were dissolved in a solvent to prepare a solution having a solid content concentration of 5.0% by mass. This solution was filtered through a 0.1 μm Teflon (registered trademark) filter to obtain a positive resist solution. However, the resist film thickness was 0.15 μm. The obtained resist film was subjected to surface exposure using EUV light (wavelength 13 nm) while changing the exposure amount by 0.5 mJ in the range of 0 to 10.0 mJ, and further baked at 100 ° C. for 90 seconds. Then, using a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution, the dissolution rate at each exposure amount was measured to obtain a sensitivity curve. In this sensitivity curve, the exposure amount when the dissolution rate of the resist is saturated was defined as sensitivity. Separately, a resist having a film thickness of 0.3 μm was prepared, and the film thickness after exposure with respect to the film thickness before 5 mJ / cm ² exposure was measured and evaluated as the amount of outgas. These results are shown in Table 8.
From the results of Table 8, it can be seen that the resist composition of the present invention is superior in sensitivity and low outgas compared to the composition of the comparative example in the property evaluation by exposure with EUV light.

[Examples EUUVN-1 to EUUVN-21 and comparative example euvn-1 · euvn-2] [Pattern preparation and evaluation (EUV)]
The components shown in Table 5 were dissolved in a solvent to prepare a solution having a solid content concentration of 5.0% by mass. This solution was filtered through a 0.1 μm Teflon (registered trademark) filter to obtain a negative resist solution. However, the resist film thickness was 0.15 μm. The obtained resist film was subjected to surface exposure using EUV light (wavelength 13 nm) while changing the exposure amount by 0.5 mJ in the range of 0 to 10.0 mJ, and further baked at 100 ° C. for 90 seconds. Then, using a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution, the dissolution rate at each exposure amount was measured to obtain a sensitivity curve. In this sensitivity curve, the exposure amount when the dissolution rate of the resist is saturated was defined as sensitivity. Separately, a resist with a film thickness of 0.3 μm was prepared, the film thickness after exposure with respect to the film thickness before 5 mJ / cm ² exposure was measured, and evaluated as the amount of outgas. These results are shown in Table 9.
From the results in Table 9, it can be seen that the resist composition of the present invention is superior in sensitivity and low outgassing as compared with the composition of the comparative example in the property evaluation by exposure with EUV light.

(Immersion exposure)
<Resist preparation>
The components of Examples Ar1 to Ar22 shown in Table 1 were dissolved in a solvent to prepare a solution having a solid content concentration of 7% by mass, and this was filtered through a 0.1 μm polyethylene filter to prepare a positive resist solution. The prepared positive resist solution was evaluated by the following method.

<Resolution evaluation>
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The prepared resist composition was applied thereon and baked at 120 ° C. for 60 seconds to form a 150 nm resist film. The wafer thus obtained was subjected to two-beam interference exposure (wet exposure) using pure water as the immersion liquid. In the two-beam interference exposure (wet), as shown in FIG. 1, a laser 1, an aperture 2, a shutter 3, three reflecting mirrors 4, 5, 6 and a condenser lens 7 are used, and a prism 8, liquid The wafer 10 having an antireflection film and a resist film was exposed through an immersion liquid (pure water) 9. The wavelength of the laser 1 was 193 nm, and the prism 8 forming a 65 nm line and space pattern was used. Immediately after exposure, the resist pattern obtained by heating at 120 ° C. for 60 seconds, developing with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 60 seconds, rinsing with pure water, and spin drying is then used for the scanning pattern. When observed using an electron microscope (S-9260 manufactured by Hitachi), a 65 nm line and space pattern was resolved.
Thus, the composition of the present application has a good image forming ability even in an exposure method via an immersion liquid.

It is the schematic of a two-beam interference exposure experiment apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser 2 Aperture 3 Shutter 4, 5, 6 Reflection mirror 7 Condensing lens 8 Prism 9 Immersion liquid 10 Wafer having antireflection film and resist film 11 Wafer stage

Claims (6)

The sulfonium salt (A) represented by the general formula (I) , and
A resin (B) that decomposes by the action of an acid and increases the solubility in an alkaline developer,
A resist composition comprising:

In general formula (I),
R ¹ represents an A reel group.
R ^{2 to} R ⁹ each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
Z is an electron withdrawing divalent linking group.
X ⁿ⁻ represents an n-valent anion.
n represents an integer of 1 to 3.
m represents the number of anions necessary for neutralizing the charge.   The resist composition according to claim 1, wherein the sulfonium salt (A) represented by the general formula (I) is a sulfonium salt compound represented by the general formula (II).

  In general formula (II),
  R ¹ Represents an aryl group.
  R ² ~ R ⁹ Each independently represents a hydrogen atom or a substituent, and may be bonded to each other to form a ring.
  Z 'represents a sulfone group.
  X ^n- Represents an n-valent anion.
  n represents an integer of 1 to 3.
  m represents the number of anions necessary for neutralizing the charge.   The resist composition according to claim 1, wherein the sulfonium salt (A) represented by the general formula (I) is a sulfonium salt compound represented by the general formula (III).

  In general formula (III),
  R ^{1 ’} Represents an aryl group.
  R ^{2 ’} ~ R ^{9 ’} Each independently represents a hydrogen atom or a substituent, and may be bonded to each other to form a ring. However, R ^{1 ’} ~ R ^{9 ’} At least one of these is a group containing an alcoholic hydroxyl group.
  Z is an electron withdrawing divalent linking group.
  X ^n- Represents an n-valent anion.
  n represents an integer of 1 to 3.
  m represents the number of anions necessary for neutralizing the charge. Furthermore, the resist composition according to any one of claims 1 to 3, wherein the resist composition is exposed with an X-ray, an electron beam or EUV.   The photosensitive film | membrane formed with the resist composition as described in any one of Claims 1-4. A pattern forming method comprising the steps of exposing and developing the photosensitive film according to claim 5 .

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