JP4431474B2 - Positive resist composition and pattern forming method using the same - Google Patents

Description

  The present invention relates to a positive resist composition used in semiconductor manufacturing processes such as ICs, circuit boards such as liquid crystals and thermal heads, and other photofabrication processes. More specifically, the present invention relates to a positive resist composition suitable for use as an exposure light source such as far ultraviolet rays of 220 nm or less and an irradiation source using an electron beam, and a pattern forming method using the same.

  The chemically amplified positive resist composition generates an acid in the exposed area by irradiation with radiation such as far ultraviolet light, and dissolves in the developing solution of the active radiation irradiated area and the non-irradiated area by a reaction using this acid as a catalyst. It is a pattern forming material that changes the properties and forms the pattern on the 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.
As an ArF light source photoresist composition, a resin in which an alicyclic hydrocarbon moiety is introduced instead of an aromatic group has been proposed for the purpose of imparting dry etching resistance. As the system becomes extremely hydrophobic, development with an aqueous solution of tetramethylammonium hydroxide (hereinafter referred to as TMAH), which has been widely used as a resist developer, becomes difficult, or the resist peels off from the substrate during development. Phenomenon such as end.
Various resist compositions have been found to satisfy various performances. For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2002-268224) discloses a photosensitive composition using a specific acid generator. Yes.

  However, these positive photoresist compositions still have insufficient properties in terms of PEB temperature dependency, line edge roughness, exposure latitude, and pattern profile.

JP 2002-268224 A

  An object of the present invention is to provide a positive resist composition excellent in PEB temperature dependency, line edge roughness, exposure latitude, and pattern profile, and a pattern forming method using the same.

  The present invention is a positive resist composition having the following constitution and a pattern forming method using the same, whereby the above object of the present invention is achieved.

(1)
(A) a resin containing a repeating unit having a group represented by the general formula (A1) and having increased solubility in an alkali developer by the action of an acid;
(B) a compound that generates a C2- or C3-alkanesulfonic acid that is fluorine-substituted by irradiation with actinic rays or radiation, and (C) a solvent ,
The resin (A) further contains a repeating unit represented by the general formula (3),
A positive resist composition, wherein the sulfonic acid generated from the compound (B) is a sulfonic acid substituted at the α-position with a fluorine atom .

一般式（３）中、Ｒ _1a は、水素原子又はメチル基を表す。
Ｗ ₁ は、単結合、アルキレン基、エーテル基、チオエーテル基、カルボニル基、エステル基よりなる群から選択される単独あるいは２つ以上の基の組み合わせを表す。
Ｌｃは、下記一般式（ＩＶ）、（Ｖ−１）〜（Ｖ−６）及び（ＶＩ）のいずれかで表されるラクトン残基を表す。

Ｒ _a1 、Ｒ _b1 、Ｒ _c1 、Ｒ _d1 及びＲ _e1 は各々独立に、水素原子又は炭素数１〜４のアルキル基を表す。ｍ及びｎは各々独立に０〜３の整数を表し、ｍ＋ｎは２以上６以下である。

一般式（Ｖ−１）〜（Ｖ−６）において、Ｒ _1b 〜Ｒ _5b は、各々独立に水素原子、アルキル基、シクロアルキル基、アルケニル基又はＣＯＯＲ _6b を表す。ここでＲ _6b はアルキル基を表す。また、Ｒ _1b 〜Ｒ _5b の内の２つは、結合して環を形成してもよい。

In general formula (A1),
R _{2 to} R ₄ each independently represents an alkyl group or a cycloalkyl group, and the total number of carbon atoms constituting R _{2 to} R ₄ is 4 to 8 . At least two of R _{2 to} R ₄ may be bonded to form a ring.
m is 0 or 1.
W represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a combination of two or more groups selected from the group consisting of ester groups.

In general formula (3), R _1a represents a hydrogen atom or a methyl group.
W ₁ represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a group of two or more groups selected from the group consisting of an ester group.
Lc represents a lactone residue represented by any one of the following general formulas (IV), (V-1) to (V-6) and (VI).

R _a1 , R _b1 , R _c1 , R _d1 and R _e1 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.

In General Formulas (V-1) to (V-6), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, or COOR _6b . Here, R _6b represents an alkyl group. Two of R _{1b to} R _5b may be bonded to form a ring.

  (2) The positive resist composition as described in (1) above, wherein the repeating unit having a group represented by the general formula (A1) is a repeating unit represented by the general formula (A2).

In general formula (A2),
R ₁ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.
R _{2 to} R ₄ each independently represents an alkyl group or a cycloalkyl group, and the total number of carbon atoms constituting R _{2 to} R ₄ is 4 to 8 . At least two of R _{2 to} R ₄ may be bonded to form a ring.
m is 0 or 1.
W represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a combination of two or more groups selected from the group consisting of ester groups.

Further preferred embodiments include the following configurations.
(3) The positive resist composition as described in (1) or (2) above, wherein the resin (A) further contains a repeating unit represented by the general formula (1).

  In the general formula (1), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG represents a group represented by any one of the following general formulas (pI) to (pV).

In the formula, 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 forms an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to do.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. However, at least one of R _{12 to} R ₁₄ and any one of R ₁₅ and R ₁₆ represents an alicyclic hydrocarbon 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 an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon 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 an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

  (4) Any of the above (1) to (3), wherein the compound of component (B) is a compound that generates pentafluoroethanesulfonic acid or perfluoropropanesulfonic acid upon irradiation with actinic rays or radiation A positive resist composition as described above.

(5) Any of the above (1) to (4), wherein the solvent (C) is a mixed solvent obtained by mixing at least one selected from the following group a and at least one selected from group b and group c The positive resist composition as described in 1. above.
Group a: Propylene glycol monoalkyl ether carboxylate chain ketone Group b: alkyl lactate Propylene glycol monoalkyl ether cyclic ketone Group c: γ-butyrolactone carbonate

  (6) The positive resist composition as described in any one of (1) to (5) above, wherein the resin (A) further contains a repeating unit represented by the general formula (2).

In general formula (2), R ₃₀ represents a hydrogen atom or a methyl group.
R _{31 to} R ₃₃ each independently represents a hydrogen atom, a hydroxyl group or an alkyl group, provided that at least one represents a hydroxyl group.

  (7) The positive resist composition as described in any one of (1) to (6) above, wherein the component (B) is one selected from sulfonium salt compounds and iodonium salt compounds.

(8) In addition to any of the above (1) to (7), further comprising a dissolution inhibiting compound having a molecular weight of 3000 or less, which decomposes by the action of an acid and increases the solubility in an alkaline developer. The positive resist composition as described.
(9) The positive resist composition as described in any one of (1) to (8), further comprising at least one of a basic compound and fluorine and / or a silicon-based surfactant.

一般式（Ｂ１−１）において、Ｒ _201b1 〜Ｒ _203b1 は、各々独立にアリール基を表す。
Ｘb ^- は、フッ素置換された炭素数２又は３のアルカンスルホン酸の−ＳＯ ₃ Ｈの水素原子がとれたスルホン酸アニオンを表す。
（１６）
化合物（Ｂ）が下記一般式（Ｂ１−２）で表される化合物である、（１）〜（１４）のいずれかに記載のポジ型レジスト組成物。

一般式（Ｂ１−２）において、Ｒ _201b2 は、アリール基を表す。Ｒ _203b2 とＲ _203b2 とは互いに連結してアルキレン基を形成する。
Ｘb ^- は、フッ素置換された炭素数２又は３のアルカンスルホン酸の−ＳＯ ₃ Ｈの水素原子がとれたスルホン酸アニオンを表す。
（１７） 上記（１）〜（１６）のいずれかに記載のレジスト組成物よりレジスト膜を形成し、該レジスト膜を露光、現像することを特徴とするパターン形成方法。 (10) The basic compound has a compound selected from an imidazole structure, a diazabicyclo structure, an onium hydroxide structure, an onium carboxylate structure, a trialkylamine structure, an aniline structure and a pyridine structure, a hydroxyl group and / or an ether bond. The positive resist composition as described in (9), which is an alkylamine derivative or an aniline derivative having a hydroxyl group and / or an ether bond.
(11) The positive resist composition as described in (1), wherein Lc in the general formula (3) is a lactone residue represented by the general formula (V-1).
(12) The resin (A) is a resin composed only of a repeating unit represented by the general formula (A2) and a repeating unit represented by the general formula (3). A positive resist composition.
(13) The resin (A) contains at least one of the repeating unit represented by the general formula (1) and the repeating unit represented by the general formula (2), and the repeating unit represented by the general formula (A2) And the positive resist composition as described in any one of (3) to (11) above, wherein the resin is composed of only a repeating unit represented by the general formula (3) or (11).
(14) The sulfonic acid generated from the compound (B) is perfluoroethanesulfonic acid, perfluoro-n-propanesulfonic acid, or perfluoroisopropanesulfonic acid, according to any one of (1) to (13) The positive resist composition as described.
(15) The positive resist composition according to any one of (1) to (14), wherein the compound (B) is a compound represented by the following general formula (B1-1).

In General Formula (B1-1), R _{201b1 to} R _203b1 each independently represents an aryl group.
Xb ^- represents -SO ₃ H sulfonate anion resulting from removal of the hydrogen atom of fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.
(16)
The positive resist composition according to any one of (1) to (14), wherein the compound (B) is a compound represented by the following general formula (B1-2).

In General Formula (B1-2), R _201b2 represents an aryl group. R _203b2 and R _203b2 are linked to each other to form an alkylene group.
Xb ^- represents -SO ₃ H sulfonate anion resulting from removal of the hydrogen atom of fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.
(17) A pattern forming method comprising: forming a resist film from the resist composition according to any one of (1) to (16 ) above; and exposing and developing the resist film.

  According to the positive resist composition of the present invention, a pattern excellent in sensitivity, PEB temperature dependency, line edge roughness, exposure latitude, and pattern profile can be formed.

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).
In addition, although this invention has a structure as described in a claim, it described below also for reference below.

[1] Resin that increases the solubility in an alkaline developer by the action of an acid (component A)
The resin (acid-decomposable resin) that is decomposed by the acid used in the positive resist composition of the present invention and has increased solubility in an alkaline developer contains a repeating unit having a group represented by the general formula (A1) To do.

In general formula (A1),
R _{2 to} R ₄ each independently represents an alkyl group or a cycloalkyl group, and the total number of carbon atoms constituting R _{2 to} R ₄ is 9 or less, preferably 4 to 8, most preferably, 5-7. At least two of R _{2 to} R ₄ may be bonded to form a ring. m is 0 or 1.
W represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a combination of two or more groups selected from the group consisting of ester groups.

The alkyl group as R _{2 to} R ₄ may be linear or branched. For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group , T-butyl group (preferably having 1 to 6 carbon atoms).
The alkyl group may have a substituent, and examples of the substituent include a hydroxyl group, a halogen atom, and an alkoxy group (preferably having 1 to 4 carbon atoms).

As the cycloalkyl group represented by R _{2 to} R ₄ , those having 3 to 6 carbon atoms such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group are preferable.
Examples of the substituent for the cycloalkyl group include a hydroxyl group, a halogen atom, and an alkyl group (preferably having 1 to 3 carbon atoms).

Examples of the alkylene group for W include groups represented by the following formulae.
− [C (R _i ) (R _j )] r _k −
In the above formula, R _i and R _j represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group, and both may be the same or different. 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 a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the substituent that the alkyl group may have include a hydroxyl group, a halogen atom, and an alkoxy group.
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 substituent that the alkoxy group may have include an alkoxy group.
Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r _k is an integer from 1 to 10.

  The repeating unit represented by the general formula (A1) is preferably a repeating unit represented by the general formula (A2).

In general formula (A2), R ₁ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.
R _{2 to} R ₄ , W, and m are as defined in general formula (A1).

  The repeating unit represented by the general formula (A2) is preferably a repeating unit represented by the general formula (A3).

In formula (A3), R ₁ has the same meaning as R ₁ in formula (A2). R ₂ represents an alkyl group having 1 to 6 carbon atoms, Z represents a divalent linking group having 2 to 6 carbon atoms forming a ring structure, and the total number of carbon atoms constituting R ₂ and Z is 3 -9, preferably 4-8, most preferably 5-7. The ring formed by Z may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond or a carbonyl group.

  The repeating unit represented by the general formula (A2) is further preferably a repeating unit represented by the general formula (A4).

R ₁ , R ₂ and Z in the general formula (A4) have the same meanings as those in the general formula (A3).

  The repeating unit represented by the general formula (A2) is most preferably a repeating unit represented by the general formula (A5).

R ₁ and R ₂ in the general formula (A5) are synonymous with those in the general formula (A3). n represents an integer of 2 to 8, and the sum of n and the number of carbon atoms constituting R ₂ is 3 to 9, preferably 4 to 8, and most preferably 5 to 7.

  Below, the structural unit derived from a methacrylic ester is illustrated as a preferable specific example of the repeating unit represented by general formula (A2). Likewise preferred are structural units derived from acrylates, α-hydroxymethyl acrylates, etc., rather than methacrylic esters.

Further, the resin contained in the positive resist composition of the present invention is a resin (acid-decomposable resin) whose solubility in an alkaline developer is increased by the action of an acid, and is decomposed by the action of an acid to produce an alkali-soluble group. Contains a repeating unit having a group (acid-decomposable group).
Examples of the acid-decomposable group include a group represented by —C (═O) —X ₁ —R ₀ . As R ₀ , tertiary alkyl groups such as t-butyl group and t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxyethyl group and the like 1-alkoxyethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3-oxocyclohexyl ester Group, 2-methyl-2-adamantyl group, mevalonic lactone residue and the like. X ₁ represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.
The structure of the repeating unit having an acid-decomposable group is not particularly limited, and examples thereof include a (meth) acrylic acid ester repeating unit and a repeating unit having an alicyclic structure in the main chain.

  As the repeating unit having an acid-decomposable group, it can be contained as a repeating unit represented by the general formula (1).

  In general formula (1), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG represents an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pV). It is a group containing.

In the formula, 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 forms an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to do.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. However, at least one of R _{12 to} R ₁₄ and any one of R ₁₅ and R ₁₆ represents an alicyclic hydrocarbon 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 an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon 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 an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

The linking group of A is 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, or a urea group, or a combination of two or more groups Represents. Examples of the alkylene group in A include groups represented by the following formulas.
− [C (R _b ) (R _c )] _r −
In the formula, R _b and R _c represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyl group and an alkoxy group, and both may be the same or different. 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 a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the substituent that the alkyl group may have include a hydroxyl group, a halogen atom, and an alkoxy group (preferably having 1 to 4 carbon atoms). 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 halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r represents an integer of 1 to 10.

In the general formulas (pI) to (pV), the alkyl group in R _{12 to} R ₂₅ may be either substituted or unsubstituted, and a linear or branched alkyl group having 1 to 4 carbon atoms Represents. 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.
Further, the further substituent of the alkyl group includes an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, A carboxy group, an alkoxycarbonyl group, a nitro group, etc. can be mentioned.

The alicyclic hydrocarbon group in R _{11 to} R _{25 or} the alicyclic hydrocarbon group formed by Z and a 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 alicyclic hydrocarbon groups may have a substituent.
Below, the structural example of an alicyclic part is shown among alicyclic hydrocarbon groups.

  In the present invention, preferred examples of the alicyclic moiety include adamantyl group, noradamantyl group, decalin residue, tricyclodecanyl group, tetracyclododecanyl group, norbornyl group, cedrol group, cyclohexyl group, cycloheptyl. Group, cyclooctyl group, cyclodecanyl group and cyclododecanyl group. More preferred are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, a cyclododecanyl group, and a tricyclodecanyl group.

Examples of the substituent for these alicyclic hydrocarbon 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 a substituent selected from the group consisting of a methyl group, an ethyl group, a propyl group, and an isopropyl group. To express. Examples of the substituent that the alkyl group may have include a hydroxyl group, a halogen atom, and an alkoxy group.
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.

  In addition, from the point that profile stability (SEM resistance) when observing the obtained profile with a scanning electron microscope is good, in the general formula (1), A is a single bond, and ALG is represented as follows. The repeating unit which is a group is particularly preferred.

R ₂₆ and R ₂₇ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms.

  Specific examples of the monomer corresponding to the repeating unit represented by the general formula (1) are shown below.

  The acid-decomposable resin contained in the positive resist composition of the present invention may contain the general formula (2) as a repeating unit.

In general formula (2), R ₃₀ represents a hydrogen atom or a methyl group.
R _{31 to} R ₃₃ each independently represents a hydrogen atom, a hydroxyl group or an alkyl group, provided that at least one represents a hydroxyl group.

The alkyl group of R _{31 to} R ₃₃ is preferably an alkyl group having 1 to 5 carbon atoms, such as a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group. , T-butyl group and the like.
In the repeating unit represented by the general formula (2), one or two of R _{31 to} R ₃₃ are preferably a hydroxyl group, and two are particularly preferably a hydroxyl group.

  Although the specific example of the repeating unit represented by General formula (2) below is given, it is not limited to these.

  The acid-decomposable resin contained in the positive resist composition of the present invention can also contain the general formula (3) as a repeating unit.

In general formula (3), R _1a represents a hydrogen atom or a methyl group.
W ₁ represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a group of two or more groups selected from the group consisting of an ester group.
Lc represents a lactone residue represented by any one of the following general formulas (IV), (V-1) to (V-6) and (VI).

R _a1 , R _b1 , R _c1 , R _d1 and R _e1 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.

In General Formulas (V-1) to (V-6), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, or COOR _6b . Here, R _6b represents an alkyl group. Two of R _{1b to} R _5b may be bonded to form a ring.

The alkylene group of W ₁ in the general formula (3) include a group represented by the following formula.
− [C (Rf) (Rg)] r ₁ −
In the above formula, Rf and Rg represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyl group or an alkoxy group, and both may be the same or different. 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 a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the substituent that the alkyl group may have include a hydroxyl group, a halogen atom, and an alkoxy group.
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 substituent that the alkoxy group may have include an alkoxy group.
Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r ₁ is an integer of 1 to 10.

Examples of the alkyl group having 1 to 4 carbon atoms of R _{a1 to} R _e1 in the general formula (IV) include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, t- A butyl group etc. can be mentioned.
Examples of the alkyl group as R _{1b to} R _5b in formulas (V-1) to (V-6) include linear and branched alkyl groups, which may have a substituent. A linear or branched alkyl group having 1 to 12 carbon atoms is preferable, a linear or branched alkyl group having 1 to 10 carbon atoms is more preferable, and a methyl group, an ethyl group, or a propyl group is more preferable. Isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group.
R _6b in COOR _6b as R _{1b to} R _{5b in the} general formulas (V-1) to (V-6) is preferably a linear or branched alkyl group having 1 to 12 carbon atoms, and more preferably. Is a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl. Group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group and decyl group.

As a cycloalkyl group in R _<1b > -R < _5b >, C3-C8 things, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, are preferable.
As an alkenyl group in R _<1b > -R < _5b >, C2-C6 things, such as a vinyl group, a propenyl group, a butenyl group, a hexenyl group, are preferable.
Examples of the ring formed by combining two of R _{1b to} R _5b include a 3- to 8-membered ring such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring. .
In addition, R _<1b > -R < _5b > in general formula (V-1)-(V-6) may be connected with any of the carbon atoms which comprise the cyclic skeleton.

  Moreover, as a preferable substituent which the said alkyl group, a cycloalkyl group, and an alkenyl group may have, a C1-C4 alkoxy group, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), Examples thereof include an acyl group having 2 to 5 carbon atoms, an acyloxy group having 2 to 5 carbon atoms, a cyano group, a hydroxyl group, a carboxy group, an alkoxycarbonyl group having 2 to 5 carbon atoms, and a nitro group.

Specific examples of the repeating unit having a group having a lactone structure represented by the general formula (IV), (V-1) to (V-6) or (VI) are shown below, but the present invention is limited thereto. Is not to be done.
First, although the specific example of the repeating unit of General formula (2) which has a lactone structure represented by general formula (IV) is shown below, it is not limited to these.

  Next, although the specific example of the repeating unit of General formula (3) which has a lactone structure represented by general formula (V-1)-(V-6) is shown below, it is not limited to these.

  Specific examples of the repeating unit of the general formula (3) having a lactone structure represented by the general formula (VI) are shown below.

The acid-decomposable resin used in the positive resist composition of the present invention can contain general formula (II-A) or general formula (II-B) as a repeating unit.
The repeating unit of general formula (II-A) or general formula (II-B) can be introduced from the viewpoint of adjusting the glass transition point of the polymer, improving etching resistance, and improving SEM resistance.

In 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 cyclic hydrocarbon group.
Wherein, R ₅ represents an alkyl group, cyclic hydrocarbon 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 cyclic hydrocarbon 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;

The alkyl group in R ₂₁ ′ to R ₃₀ ′ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. And 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 carboxyl 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 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, and examples of the acyloxy group include an acetoxy group.

In the acid-decomposable resin according to the present invention, the acid-decomposable group may be contained in the aforementioned —C (═O) —XA′—R ₁₇ ′.

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 cyclic hydrocarbon group in R ₅ , R ₆ and R ₁₃ ′ to R ₁₆ ′ include a cyclic alkyl group and a bridged hydrocarbon group, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, 2- List 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 do.

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 those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

  Examples of further substituents in the alkyl group, cyclic hydrocarbon 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 cyclic hydrocarbon group. Can do. 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 for 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.

  Specific examples of the repeating unit represented by the general formula (II-A) or the general formula (II-B) include the following, but the present invention is not limited to these specific examples.

The acid-decomposable resin of the present invention may contain a repeating unit represented by the following general formula (VIII).
The repeating unit of the general formula (VIII) can be introduced from the viewpoint of adjusting the glass transition point of the polymer and improving the developability and wettability (developing property of the developer) with an aqueous alkali solution.

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, a cycloalkyl group, or —OSO ₂ —R ₄₂ . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue. The alkyl group and cycloalkyl group of R ₄₁ and R ₄₂ may be substituted with a halogen atom or the like.

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

  In addition to the above repeating structural units, the acid-decomposable resin of the present invention has dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required properties of resist, resolving power, heat resistance, and sensitivity. Various repeating structural units can be contained for the purpose of adjusting the above.

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

Thereby, the performance required for the acid-decomposable resin, in particular,
(1) Solubility in coating solvent,
(2) Film formability (glass transition point),
(3) Alkali developability,
(4) Membrane slip (hydrophobic, alkali-soluble group selection),
(5) Adhesion of unexposed part to substrate,
(6) Dry etching resistance,
Etc. can be finely adjusted.

  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 acid-decomposable resins, the molar ratio of each repeating structural unit is the resist dry etch resistance, standard developer suitability, substrate adhesion, resist profile, and general resist performance required for resolving power, heat resistance, and sensitivity. It is set appropriately in order to adjust etc.

The content of the repeating unit represented by the general formula (A2) having the group represented by the general formula (A1) is preferably 15 to 70 mol%, more preferably 20 to 60 mol in all the repeating units constituting the resin. %, More preferably 25 to 50 mol%.
The content of the repeating unit having an acid-decomposable group is preferably from 0 to 50 mol%, more preferably from 0 to 30 mol%, still more preferably from 0 to 20 mol% in all repeating structural units.
As for content of the repeating unit represented by General formula (1), 0-50 mol% is preferable in all the repeating structural units, More preferably, it is 0-30 mol%, More preferably, it is 0-20 mol%.
The content of the repeating unit of the general formula (2) is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, still more preferably 15 to 30 mol% in all repeating units.

The content of the repeating unit of the general formula (3), which is a further copolymer component, is 40 mol% or less based on the total number of moles of the repeating units represented by the general formulas (A2), (1) and (2). More preferably, it is 30 mol% or less, More preferably, it is 20 mol% or less.
The content of repeating units of the general formulas (II-A) and (II-B), which are further copolymerization components, is preferably 30 mol% or less, more preferably 20 mol% or less, even more preferably in all repeating structural units. Is 15 mol% or less.
The content of the repeating unit of the general formula (VIII), which is a further copolymer component, is preferably 30 mol% or less, more preferably 20 mol% or less, still more preferably 15 mol% or less in all repeating structural units.
Further, the content of the repeating structural unit based on the monomer of the further copolymer component in the resin can be appropriately set according to the performance of the desired resist, but the general formulas (A2) and (1) And 30 mol% or less is preferable with respect to the total mole number of the repeating unit represented by (2), More preferably, it is 20 mol% or less, More preferably, it is 15 mol% or less.
When the resist 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 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 this is added to a reaction solvent, for example, cyclic ethers such as tetrahydrofuran and 1,4-dioxane, methyl ethyl ketone, methyl isobutyl. Ketones, ketones such as cyclohexanone, and the resist composition of the present invention such as propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether, which will be described later, are uniformly dissolved in a solvent, and then inert such as nitrogen or argon. Polymerization is started using a commercially available radical initiator (azo initiator, peroxide, etc.) as necessary under a 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 usually 10% by mass or more, preferably 15% by mass or more, and more preferably 20% by mass or more. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 130 ° C, more preferably 50 ° C to 110 ° C.
The repeating structural units represented by the above specific examples may be used singly or in combination.
In the present invention, the resins may be used alone or in combination.

The weight average molecular weight of the resin according to the present invention is preferably 1,000 to 200,000, more preferably 3,000 to 50,000, and still more preferably 5,000 to 20 as a polystyrene-converted value by the GPC method. 1,000, particularly preferably 7,000 to 10,000. That is, it is preferably 1,000 or more from the viewpoint of weight-average molecular weight heat resistance and dry etching resistance, and is preferably 200,000 or less from the viewpoint of developability, viscosity, and film forming property.
The degree of dispersion (Mw / Mn) is usually 1 to 5, preferably 1 to 4, more preferably 1 to 3. 5 or less is preferable from the viewpoints of resolution, resist shape, pattern side wall, roughness and the like.

  In the positive resist composition of the present invention, the blending amount of all the resins according to the present invention in the entire resist composition is preferably 40 to 99.99% by mass, more preferably 50 to 99.99%, based on the total solid content of the resist. 97% by mass.

[2] Compound (B) that generates a C2- or C3-alkanesulfonic acid substituted with fluorine upon irradiation with actinic rays or radiation
The photosensitive composition of the present invention contains a compound (also referred to as component B or photoacid generator (B)) that generates a C2- or C3-alkanesulfonic acid that is fluorine-substituted by irradiation with actinic rays or radiation. .

  Examples of the fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms include 1,1,2,3,3,3-hexafluoropropanesulfonic acid, 1,1,1,3,3,3-hexafluoro- Examples include 2-propanesulfonic acid, 2,2,2-trifluoroethanesulfonic acid, perfluoroethanesulfonic acid, perfluoro-n-propanesulfonic acid, and perfluoroisopropanesulfonic acid. More preferred are sulfonic acids in which the α-position of the sulfonic acid is substituted with a fluorine atom, and more preferred are perfluoroethanesulfonic acid, perfluoro-n-propanesulfonic acid, and perfluoroisopropanesulfonic acid. Particularly preferred is perfluoro-n-propanesulfonic acid.

  Examples of the compound that generates a fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms by irradiation with actinic rays or radiation include a fluorine-substituted sulfonium salt compound or iodonium salt compound of an alkanesulfonic acid having 2 or 3 carbon atoms, and A fluorine-substituted ester compound of a C 2 or C 3 alkanesulfonic acid is preferable, and a compound represented by any one of the following general formulas (B1) to (B5) is more preferable.

Formula (B1) or a compound represented by (B2) is, Xb ^- is a compound the anion of fluorine-substituted alkanesulfonic acid of carbon number 2 or 3, in the general formula (B3) ~ (B5) The compound represented is a compound in which a hydrogen atom of —SO ₃ H of an alkanesulfonic acid having 2 or 3 carbon atoms in which X _1b is substituted with fluorine is removed and bonded as a monovalent group.

In the general formula (B1), R _201b , R _202b and R _203b each independently represents an organic group.
Xb ^- represents -SO ₃ H sulfonate anion resulting from removal of the hydrogen atom of fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.

The carbon number of the organic group as R _201b , R _202b and R _203b is generally 1-30, preferably 1-20.
Two of R _{201b to} R _203b 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.
Examples of the group formed by combining two _{members out} of R _{201b to} R _203b include an alkylene group (eg, butylene group, pentylene group).
Specific examples of the organic group as R _201b , R _202b and R _203b include corresponding groups in the compounds (B1a), (B1b) and (B1c) described later.

In addition, the compound which has two or more structures represented by general formula (B1) may be sufficient. For example, the general formula at least one of R _201b to R _203b of the compounds represented by (B1) is at least one bond with structure of R _201b to R _203b of another compound represented by formula (B1) It may be a compound.
More preferred components (B1) include compounds (B1a), (B1b), and (B1c) described below.

Compound (B1a) is at least one is an aryl group R _201b to R _203b of the general formula (B1), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
In the arylsulfonium compound, all of R _{201b to} R _203b may be an aryl group, or a part of R _{201b to} R _203b may be an aryl group with the remaining being an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compounds include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, and compounds in which the alkyl group in these compounds is a cycloalkyl group.
Examples of the aryl group of the arylsulfonium compound include an aryl group composed of a hydrocarbon and a heteroaryl group containing a hetero atom such as a nitrogen atom, a sulfur atom, or an oxygen atom. The aryl group composed of hydrocarbon is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. Examples of the heteroaryl group include a pyrrole group, an indole group, a carbazole group, and a thiophene group, and an indole group is preferable. 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 or 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.

Examples of the substituent that the aryl group, alkyl group and cycloalkyl group of R _{201b to} R _203b may have include a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms), an alkoxy group Examples thereof include a group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group. Moreover, about cyclic structures, such as an aryl ring and a cyclo ring in each group, an alkyl group (for example, C1-C15) can be further mentioned as a substituent.

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, particularly 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 _{201b to} R _203b or may be substituted with all three. Moreover, about an aryl group, an alkyl group (for example, C1-C15) can be mentioned as a substituent further. The substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (B1b) will be described.
The compound (B1b) is a compound in the case where R _{201b to} R _203b in the general formula (B1) 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 not containing an aromatic ring as R _{201b to} R _203b generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
R _{201b to} R _203b are each independently preferably an alkyl group (particularly an alkoxycarbonylmethyl group as a substituted alkyl group), a cycloalkyl group, a linear, branched or cyclic group which may have a double bond in the chain. It is an oxoalkyl group, an allyl group or a vinyl group, more preferably a linear, branched or cyclic 2-oxoalkyl group, and most preferably a linear or branched 2-oxoalkyl group.
The alkyl group as R _{201b to} R _203b may be either linear or branched, and is preferably a linear or branched alkyl group having 1 to 20 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, Butyl group, pentyl group).
The cycloalkyl group as R _{201b to} R _203b is preferably a cycloalkyl group having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group).

The 2-oxoalkyl group as R _{201b to} R _203b may be linear, branched or cyclic, and may have a double bond. Preferable examples include a group having> C═O at the 2-position of the alkyl group.
The alkoxy group in the alkoxycarbonylmethyl group as the substituted alkyl group for R _{201b to} R _203b is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group). Can do.
Each group as R _{201b to} R _203b may be substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, a nitro group, or the like.

  The compound (B1c) is a compound represented by the following general formula (B1c), and is a compound having an arylacylsulfonium salt structure.

In the general formula (B1c),
_R213 represents an aryl group, preferably a phenyl group or a naphthyl group. Examples of the substituent which may be possessed by the aryl group R _213, e.g., an alkyl group, an alkoxy group, an acyl group, a nitro group, a hydroxyl group, an alkoxycarbonyl group and a carboxy group.
R ₂₁₄ and R ₂₁₅ each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
Y ₂₀₁ and Y ₂₀₂ each independently represents an alkyl group, a cycloalkyl group, an aryl group or a vinyl group.
X ⁻ represents a sulfonate anion in which a hydrogen atom of —SO ₃ H of a fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms is removed.

R ₂₁₃ and R ₂₁₄ may be bonded to form a ring structure, R ₂₁₄ and R ₂₁₅ may be bonded to form a ring structure, and Y ₂₀₁ and Y ₂₀₂ are bonded to each other. To form a ring structure. These ring structures may contain an oxygen atom, a sulfur atom, an ester bond, or an amide bond. A group formed by combining R ₂₁₃ and R ₂₁₄ , a group formed by combining R ₂₁₄ and R _215, and a group formed by combining Y ₂₀₁ and Y ₂₀₂ , respectively, are a butylene group. And a pentylene group.

The alkyl group as R ₂₁₄ and R ₂₁₅ is a linear or branched alkyl group having 1 to 20 carbon atoms (for example, methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, t-butyl group). Is preferred.
The cycloalkyl group as R ₂₁₄ and R ₂₁₅ is preferably a cycloalkyl group having 3 to 20 carbon atoms (for example, cyclopropyl group, cyclobutyl group, cyclohexyl group).

The alkyl group as Y ₂₀₁ and Y ₂₀₂ may have a substituent, may have an oxo group in the alkylene chain, and is a linear or branched alkyl group having 1 to 20 carbon atoms (for example, (Methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, t-butyl group) are preferred.
Examples of the alkyl group having a substituent include an alkoxycarbonylalkyl group and a carboxyalkyl group, and examples of the alkyl group having an oxo group include a 2-oxoalkyl group.

Examples of the 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group.
The alkoxycarbonyl group in the alkoxycarbonylalkyl group is preferably an alkoxycarbonyl group having 2 to 20 carbon atoms.

The cycloalkyl group as Y ₂₀₁ and Y ₂₀₂ is preferably a cycloalkyl group having 3 to 20 carbon atoms (for example, a cyclopropyl group, a cyclobutyl group, a cyclohexyl group), and has a substituent similarly to the above alkyl group. The alkylene chain may have an oxo group.

The aryl group as Y ₂₀₁ and Y ₂₀₂ is preferably a phenyl group or a naphthyl group, more preferably a phenyl group.

Each group as R ₂₁₄ , R ₂₁₅ , Y ₂₀₁ and Y ₂₀₂ may have a substituent, and examples of the substituent include an aryl group (for example, 6 to 15 carbon atoms), an alkoxy group (for example, carbon (Chemical formula 1-15), an alkoxycarbonyl group (C2-C20), a carboxyl group, a halogen atom, a hydroxyl group, a phenylthio group, etc. can be mentioned. Moreover, about cyclic structures, such as an aryl ring and a cyclo ring in each group, an alkyl group (for example, C1-C15) can be further mentioned as a substituent.

Y ₂₀₁ and Y ₂₀₂ are preferably an alkyl group or cycloalkyl group having 4 or more carbon atoms, more preferably an alkyl group or cycloalkyl group having 4 to 16, and more preferably 4 to 12.
In addition, at least one of R ₂₁₄ or ₂₁₅ is preferably an alkyl group or a cycloalkyl group, and more preferably both R ₂₁₄ and R ₂₁₅ are an alkyl group or a cycloalkyl group.

In general formula (B2),
_R204b and _R205b each independently represents an aryl group, an alkyl group or a cycloalkyl group.
Xb ^- represents -SO ₃ H sulfonate anion resulting from removal of the hydrogen atom of fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.
The aryl group for R _204b and R _205b is preferably a phenyl group or a naphthyl group, more preferably a phenyl group.
As the alkyl group and cycloalkyl group as R _204b and R _205b , a linear or branched alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group), Examples thereof include a cycloalkyl group having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group).

In general formula (B3),
A represents an alkylene group, an alkenylene group or an arylene group.
X _1b represents a monovalent group formed by removing the —SO ₃ H hydrogen atom of a fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.

In general formula (B4),
R _208b represents an alkyl group, a cycloalkyl group, or an aryl group.
R _209b represents an alkyl group, a cycloalkyl group, a cyano group, or an alkoxycarbonyl group, and preferably a halogen-substituted alkyl group, a cycloalkyl group, or a cyano group.
The alkyl group and cycloalkyl group as R _209b may be an oxoalkyl group or oxocycloalkyl group having an oxo group in the alkylene chain.
X _1b represents a monovalent group formed by removing the —SO ₃ H hydrogen atom of a fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.

In general formula (B5),
R _210b and R _211b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a cyano group, a nitro group or an alkoxycarbonyl group, preferably a halogen-substituted alkyl group or a cycloalkyl group, a nitro group or a cyano group. is there.
R _212b represents a hydrogen atom, an alkyl group, a cycloalkyl group, a cyano group or an alkoxycarbonyl group.
X _1b represents a monovalent group formed by removing the —SO ₃ H hydrogen atom of a fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms.

  Each group in the general formulas (B3) to (B5) may have a substituent. Examples of the substituent include an aryl group (for example, 6 to 15 carbon atoms) and an alkoxy group (for example, 1 carbon atom). -15), halogen atoms, hydroxyl groups, phenylthio groups and the like. Moreover, about cyclic structures, such as an aryl ring and a cyclo ring in each group, an alkyl group (for example, C1-C15) can be further mentioned as a substituent.

  Preferably, it is a compound represented by general formula (B1), More preferably, it is a compound represented by general formula (B1a)-(B1c).

  Specific examples of the preferred compound (B) are shown below.

Compound (B) can be synthesized by a conventional method for synthesizing a general sulfonium-type photoacid generator, for example, a method described in JP-A-2002-268223.
The content of the compound (B) in the resist composition (solid content) is preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass, and 1 to 7% by mass. More preferably.

[3] Other compounds that generate acid upon irradiation with actinic rays or radiation (combined photoacid generator)
In the present invention, in addition to the compound (B), a compound capable of generating an acid upon irradiation with an actinic ray or radiation may be further used in combination.

The addition amount of other acid generators that can be used in combination is usually 100/0 to 20/80, preferably 100/0 to 40/60, more preferably in molar ratio (compound (B) / other acid generators). Is 100/0 to 50/50.
Examples of such an acid generator include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or an actinic ray or radiation used for a microresist. A known compound that generates an acid by irradiation and a mixture 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 that generate an acid upon irradiation with actinic rays or radiation that may be used in combination, compounds represented by the following general formula (ZI), (ZII), or (ZIII) can be exemplified.

In the general formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a non-nucleophilic anion, preferably sulfonate anion, carboxylate anion, bis (alkylsulfonyl) amide anion, tris (alkylsulfonyl) methide anion, BF ⁴⁻ , PF ⁶⁻ , SbF ^{6− and the} like. An organic anion having a carbon atom is preferable.

  Preferable organic anions include organic anions represented by the following general formula.

In the above organic anion,
Rc ₁ represents an organic group.
Examples of the organic group for Rc ₁ include those having 1 to 30 carbon atoms, and preferably an alkyl group, an aryl group, or a plurality thereof, which may be substituted, is a single bond, —O—, —CO ₂ —. , —S—, —SO ₃ —, —SO ₂ N (Rd ₁ ) — and the like.
Rd ₁ represents a hydrogen atom or an alkyl group.
Rc ₃ , Rc ₄ and Rc ₅ each independently represents an organic group.
Preferred examples of the organic group for Rc ₃ , Rc ₄ , and Rc ₅ include the same organic groups as those for Rb ₁ , and most preferably a perfluoroalkyl group having 1 to 4 carbon atoms.
Rc ₃ and Rc ₄ may combine to form a ring. Examples of the group formed by combining Rc ₃ and Rc ₄ include an alkylene group and an arylene group. A perfluoroalkylene group having 2 to 4 carbon atoms is preferred.
As the organic group of Rc ₁ and Rc _{3 to} Rc ₅ , the most preferred is an alkyl group substituted at the 1-position with a fluorine atom or a fluoroalkyl group, or a phenyl group substituted with a fluorine atom or a fluoroalkyl group. By having a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by light irradiation is increased and the sensitivity is improved.

The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
It is also possible to form the two members ring structure of the R ₂₀₁ to R _203, 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).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (ZI-1), (ZI-2) and (ZI-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 (ZI) components include compounds (ZI-1), (ZI-2), and (ZI-3) described below.

The compound (ZI-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compound, i.e., a compound having 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, and the rest may be an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.
The aryl group of the arylsulfonium compound is preferably an aryl group such as a phenyl group or a naphthyl group, or a heteroaryl group such as an indole residue or a pyrrole residue, more preferably a phenyl group or an indole residue. 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 that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.
The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include 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 They are a C1-C4 alkyl group and a C1-C4 alkoxy group. 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 (ZI-2) will be described.
Compound (ZI-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group containing no 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, a linear, branched, cyclic 2-oxoalkyl group, an allyl group, or a vinyl group, more preferably a linear, branched, cyclic 2 -An oxoalkyl group, an alkoxycarbonylmethyl group, and most preferably a linear, branched 2-oxoalkyl group.

The alkyl group as R ₂₀₁ to R ₂₀₃ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group having 1 to 10 carbon atoms, e.g., methyl group, ethyl group, propyl Group, butyl group, pentyl group and the like. The alkyl group is particularly preferably an alkoxycarbonylmethyl group.
The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably a cycloalkyl group having 3 to 10 carbon atoms, e.g., cyclopentyl, cyclohexyl group and a norbornyl group.
The 2-oxoalkyl group as R _{201 to} R ₂₀₃ may be linear, branched or cyclic, and is preferably a group having> C═O at the 2-position of the above alkyl group or cycloalkyl group Can be mentioned.
The alkoxy group in the alkoxycarbonylmethyl group as R ₂₀₁ to R _203, preferably may be mentioned alkoxy groups having 1 to 5 carbon atoms (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (eg, having 1 to 5 carbon atoms), an alkoxycarbonyl group (eg, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

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

In general formula (ZI-3),
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 each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
R _x and R _y each independently represents an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, an allyl group, or a vinyl group.
Any two or more of R _{1c to} R _5c , R _6c and R _7c , and Rx and Ry may be bonded to each other to form a ring structure, which is an oxygen atom, sulfur atom, ester A bond or an amide bond may be included. Any two or more of R _1c to R _5c, as the group R _6c and R _7c, and the Rx and Ry are formed in combination, there can be mentioned a butylene group and a pentylene group.
Z _c ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of X ^{− in} formula (ZI).

The alkyl group as R _{1c to} R _7c may be linear or branched, for example, a linear and branched alkyl group having 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, such as 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.
Preferred examples of the cycloalkyl group as R _{1c to} R _7c include a cycloalkyl group having 3 to 8 carbon atoms, such as a cyclopentyl group and a cyclohexyl group.
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 ~ 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 groups and cycloalkyl groups as R _{1c to} R _7c . The alkyl group as R _x and R _y is particularly preferably an alkoxycarbonylmethyl group.
Examples of the 2-oxoalkyl 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 R _{1c to} R _5c .

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

In formula (ZII), (ZIII), R 204 ~R 207 each independently represents an aryl group, an alkyl group or a cycloalkyl group.
The aryl group of R ₂₀₄ to R _207, a phenyl group, a naphthyl group, more preferably a phenyl group.
The alkyl group as R ₂₀₄ to R ₂₀₇ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group having 1 to 10 carbon atoms, e.g., methyl group, ethyl group, propyl Group, butyl group, pentyl group and the like.
The cycloalkyl group as R ₂₀₄ to R ₂₀₇ is preferably a cycloalkyl group having 3 to 10 carbon atoms, e.g., cyclopentyl, cyclohexyl group and a 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.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of X ^{− in} formula (I).

  Examples of the compound capable of decomposing upon irradiation with actinic rays or radiation that may be used in combination include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI).

In general formulas (ZIV) to (ZVI), Ar ₃ and Ar ₄ each independently represents an aryl group.
R ₂₀₆ represents an alkyl group, a cycloalkyl group or an aryl group.
_R207 and _R208 each independently represents an alkyl group, a cycloalkyl group, an aryl group or a cyano group.
A represents an alkylene group, an alkenylene group or an arylene group.

  Of the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, compounds represented by general formulas (ZI) to (ZIII) are more preferable.

  Among the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, examples of particularly preferable compounds are listed below.

[4] Dissolution-inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as “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, it does not lower the permeability of 220 nm or less, so 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 the alicyclic structure include the same acid-decomposable groups and alicyclic structures for the repeating unit represented by the formula (1) in the aforementioned resin.
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 1 to 30% by mass and more preferably 2 to 20% by mass with respect to the solid content of the resist composition.

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

[5] Basic Compound The resist composition of the present invention may contain a basic compound in order to reduce the change in performance over time from exposure to heating, or to control the diffusibility of the acid generated by exposure. preferable.
As the basic compound, a compound having higher basicity than phenol is preferable.
As a preferable structure which a basic compound has, the structure shown by following formula (A)-(E) can be mentioned. Formulas (B) to (E) may be part of a ring structure.

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, a cycloalkyl group having 3 to 20 carbon atoms, and 1 to 20 carbon atoms. Or a cycloalkyl group having 3 to 20 carbon atoms 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, and may have a substituent. More preferred compounds include compounds having an imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, trialkylamine structure, aniline structure or pyridine structure, alkylamine derivatives having a hydroxyl group and / or an ether bond, hydroxyl groups and / or Or the aniline derivative which has an ether bond etc. can be mentioned.

  Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole, and the like. The compound having a diazabicyclo structure is 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] noner-5-ene, 1,8-diazabicyclo [5,4,0]. Undecar 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 based on solid content of a resist 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.

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

  When the resist composition of the present invention contains fluorine and / or a silicon-based surfactant, when using an exposure light source of 250 nm or less, particularly 220 nm or less, good sensitivity and resolution, and less adhesion and development defects. A 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 F-top EF301, EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189, 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. Or 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 resist composition (excluding the solvent). .

[7] Organic solvent The resist composition of the present invention is used by dissolving the above components in a predetermined organic solvent.

  Examples of the organic solvent 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 and the like.

In this invention, the mixed solvent (henceforth a specific mixed solvent) which mixed at least 1 sort (s) included in the following a group and at least 1 sort (s) chosen from b group and c group is preferable.
Group a: Propylene glycol monoalkyl ether carboxylate chain ketone Group b: Alkyl lactate Propylene glycol monoalkyl ether Cyclic ketone Group c: γ-Butyrolactone Carbonate This specific mixed solvent reduces the occurrence of particles and development defects when storing resist solutions. And pattern collapse can be improved.

Specific examples of the propylene glycol monoalkyl ether carboxylate of group a include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether acetate, etc., and chain ketones include methyl ethyl ketone, 2- Examples include heptanone, 3-heptanone, 4-heptanone and the like.
Examples of the b group alkyl lactate include methyl lactate and ethyl lactate, and examples of the propylene glycol monoalkyl ether include propylene glycol monomethyl ether and propylene glycol monoethyl ether.
Examples of the group b cyclic ketones include cyclopentanone, 3-methyl-2-cyclopentanone, cyclohexanone, 2-methylcyclohexanone, 2,6-dimethylcyclohexanone, cycloheptanone, cyclooctanone, isophorone, and the like. be able to.
Examples of group c carbonates include ethylene carbonate and propylene carbonate.

  The mixing ratio of the a group and the b group is preferably 30/70 to 95/5, more preferably 35/65 to 90/10, and further preferably 40/60 to 80/20. The mixing ratio of group a and group c is preferably 85/15 to 99.9 / 0.1, more preferably 90/10 to 99.5 / 0.5, still more preferably 99/1 to 95/5. is there. The addition amount of the solvent of c group is 0.1-15 mass% in all the solvents, Preferably it is 0.5-10 mass%, More preferably, it is 1-5 mass%.

  Other solvents that do not belong to the groups a to c may be used in combination with the specific mixed solvent, but the amount of the other solvent is preferably 50% by mass or less, more preferably 40% by mass or less with respect to the specific mixed solvent. More preferred.

  The mixing ratio (mass ratio) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group is from 1/99 to 99/1, preferably from 10/90 to 90/10, more preferably from 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.

  Using these solvents, a resist composition having a total solid content concentration of usually 3 to 25% by mass, preferably 5 to 22% by mass, more preferably 7 to 20% by mass is prepared.

[8] Other additives In the resist composition of the present invention, a dye, a plasticizer, a surfactant other than the above, a photosensitizer, a compound that promotes solubility in a developer, and the like may be added to the resist composition as necessary. It can be included.

  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.

  The 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 total amount of the resin. 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 phenol 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 and European Patent 219294. 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 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.

[9] Method of Use The resist 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, a resist composition is applied onto a substrate (eg, silicon / silicon dioxide coating) used for manufacturing a precision integrated circuit element by an appropriate application method such as a spinner or a coater, and dried to form a resist film. .
The resist film is irradiated with actinic rays or radiation through a predetermined mask, baked and developed. In this way, 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, a KrF excimer laser (248 nm), an ArF excimer laser (193 nm), an F ₂ excimer laser (157 nm), an X-ray, an electron beam, etc. are preferable, and an ArF excimer laser and an F ₂ excimer laser are most preferable.

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.

(1) Synthesis of Resin (A-1) Resins (A-2) to (A-6) of the present invention were synthesized in the same manner as in Synthesis Example (1). Further, a resin (A-7) for comparison was synthesized in the same manner.
The structures of these synthesized resins are shown below. Table 1 shows the resin composition ratio, the weight average molecular weight Mw, and the molecular weight dispersity Mw / Mn.

[Examples 1-12 and Comparative Examples 1-3]
<Resist preparation>
A solution having the composition shown in Table 1 below was prepared, 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, and the results are shown in Table 1. The composition ratio of the resin is the molar ratio in order from the left.

  Hereinafter, the abbreviations in each table are as follows.

N-1: N, N-dibutylaniline N-2: N, N-dipropylaniline N-3: N, N-dihydroxyethylaniline N-4: 2,4,5-triphenylimidazole N-5: 2 , 6-Diisopropylaniline N-6: Hydroxyantipyrine N-7: Trismethoxymethoxyethylamine

W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.)
(Fluorine and silicon)
W-4: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)
W-5: KH-20 (Asahi Kasei Corporation)

〔solvent〕
Group a SL-1: Propylene glycol monomethyl ether acetate SL-2: Propylene glycol monomethyl ether propionate SL-3: 2-heptanone Group b SL-4: Ethyl lactate SL-5: Propylene glycol monomethyl ether SL-6: Cyclohexanone Group c SL-7: γ-butyrolactone SL-8: Propylene carbonate

  The structural formula of each solvent is shown below.

<Resist evaluation>
ARC29A manufactured by Brewer Science Co., Ltd. was uniformly applied to a silicon wafer with a spin coater at 78 nm, and heat-dried at 205 ° C. for 60 seconds to form an antireflection film. Thereafter, each positive resist composition immediately after preparation was applied with a spin coater and dried (PB) at the temperature shown in Table 1 for 60 seconds to form a 270 nm resist film.
This resist film is exposed with an ArF excimer laser stepper (PAS5500 / 1100 NA = 0.75 (2/3 annular illumination) manufactured by ASML) through a mask, and immediately after exposure, heated at 120 ° C. for 90 seconds on a hot plate. (PEB). 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 resist pattern.

[PEB temperature dependence]
The exposure amount that reproduces a line-and-space 1/1 with a mask size of 130 nm when heated after 120 seconds at 120 ° C. after exposure is the optimum exposure amount (Eopt), and after the exposure is performed at the optimum exposure amount, post-heating is performed. With respect to the temperature, post-heating is performed at two temperatures of + 2 ° C. and −2 ° C. (122 ° C., 118 ° C.), the obtained line and space are measured, and the line widths L ₁ and L ₂ are calculated Asked. The PEB temperature dependency was defined as the fluctuation of the line width per 1 ° C. PEB temperature change, and was calculated by the following formula.
PEB temperature dependency (nm / ℃) = | L 1 -L 2 | / 4
The smaller this value is, the smaller the performance change with respect to the temperature change is.

[Line edge roughness]
The line edge roughness (LER) is measured by using a length-measuring scanning electron microscope (SEM) to observe an isolated pattern of 120 nm, and the longitudinal edge of the line pattern from the reference line where the edge should be in the range of 5 μm. The distance was measured by 50 points using a length measuring SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated. A smaller value indicates better performance.

[Exposure latitude]
The exposure amount that reproduces a 130-nm line-and-space mask pattern is set as the optimal exposure amount, and when the exposure amount is changed, an exposure amount width that allows a pattern size of 130 nm ± 10% is obtained. Divided by the amount and expressed as a percentage. The larger the value, the smaller the performance change due to the change in exposure amount, and the better the exposure latitude (EL).

(Pattern profile)
A cross section of a part having a line width of 130 nm (line / space = 1: 1) was observed with an SEM (S-8840 manufactured by Hitachi, Ltd.) and evaluated according to the following criteria.
◯: When the angle between the pattern side wall and the substrate is 90 ± 2 degrees and the angle between the pattern side wall and the pattern surface is 90 ± 2 degrees Δ: The angle between the pattern side wall and the substrate is 85 degrees or more and less than 88 degrees Alternatively, when the angle between the pattern side wall and the pattern surface is not less than 92 degrees and less than 95 degrees, and the angle between the pattern side wall and the pattern surface is not less than 85 degrees and less than 88 degrees, or not less than 92 degrees and less than 95 degrees. When it is 95 degrees or more, when T-top shape is seen, or when the entire pattern surface is rounded

  The evaluation results are shown in Table 1.

  From the results of Table 1, it can be seen that the positive resist composition of the present invention is excellent in PEB temperature dependency, line edge roughness, exposure latitude, and profile. In particular, in the PEB temperature dependency and the line edge roughness, a remarkable advantage is recognized as compared with the comparative example.

Claims (11)

(A) a resin containing a repeating unit having a group represented by the general formula (A1) and having increased solubility in an alkali developer by the action of an acid;
(B) a compound that generates a C2- or C3-alkanesulfonic acid that is fluorine-substituted by irradiation with actinic rays or radiation, and (C) a solvent ,
The resin (A) further contains a repeating unit represented by the general formula (3),
A positive resist composition, wherein the sulfonic acid generated from the compound (B) is a sulfonic acid substituted at the α-position with a fluorine atom .

In general formula (A1),
R _{2 to} R ₄ each independently represents an alkyl group or a cycloalkyl group, and the total number of carbon atoms constituting R _{2 to} R ₄ is 4 to 8 . At least two of R _{2 to} R ₄ may be bonded to form a ring.
m is 0 or 1.
W represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a combination of two or more groups selected from the group consisting of ester groups.

In general formula (3), R _1a represents a hydrogen atom or a methyl group.
W ₁ represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a group of two or more groups selected from the group consisting of an ester group.
Lc represents a lactone residue represented by any one of the following general formulas (IV), (V-1) to (V-6) and (VI).

R _a1 , R _b1 , R _c1 , R _d1 and R _e1 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.

In General Formulas (V-1) to (V-6), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, or COOR _6b . Here, R _6b represents an alkyl group. Two of R _{1b to} R _5b may be bonded to form a ring.

  2. The positive resist composition according to claim 1, wherein Lc in the general formula (3) is a lactone residue represented by the general formula (V-1). The positive resist composition according to claim 1 or 2 , wherein the repeating unit having a group represented by the general formula (A1) is a repeating unit represented by the general formula (A2).

In general formula (A2),
R ₁ represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.
R _{2 to} R ₄ each independently represents an alkyl group or a cycloalkyl group, and the total number of carbon atoms constituting R _{2 to} R ₄ is 4 to 8 . At least two of R _{2 to} R ₄ may be bonded to form a ring.
m is 0 or 1.
W represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a combination of two or more groups selected from the group consisting of ester groups.   The positive resist composition according to claim 1, wherein the resin (A) further contains a repeating unit represented by the general formula (1).

  In the general formula (1), R represents a hydrogen atom or a methyl group, A represents a single bond or a linking group, and ALG represents a group represented by any one of the following general formulas (pI) to (pV).

  Where 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 necessary to form an alicyclic hydrocarbon group together with a carbon atom. Represents an atomic group.
  R ₁₂ ~ R ₁₆ Each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms or an alicyclic hydrocarbon group. However, R ₁₂ ~ R ₁₄ At least one of R and R ₁₅ , R ₁₆ Any of represents an alicyclic hydrocarbon group.
  R ₁₇ ~ R _{twenty one} Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that R represents ₁₇ ~ R _{twenty one} At least one of these represents an alicyclic hydrocarbon group. R ₁₉ , R _{twenty one} Any of these represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
  R _{twenty two} ~ R _{twenty five} Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that R represents _{twenty two} ~ R _{twenty five} At least one of these represents an alicyclic hydrocarbon group. R _{twenty three} And R _{twenty four} May be bonded to each other to form a ring.   The positive resist composition according to claim 1, wherein the resin (A) further contains a repeating unit represented by the general formula (2).

  In general formula (2), R ₃₀ Represents a hydrogen atom or a methyl group.
  R ₃₁ ~ R ₃₃ Each independently represents a hydrogen atom, a hydroxyl group or an alkyl group, provided that at least one represents a hydroxyl group.   The positive resin according to claim 2 or 3, wherein the resin (A) is a resin composed only of a repeating unit represented by the general formula (A2) and a repeating unit represented by the general formula (3). Type resist composition.   Resin (A) contains at least one of the repeating unit represented by general formula (1) and the repeating unit represented by general formula (2), the repeating unit represented by general formula (A2), 6. The positive resist composition according to claim 4, wherein the positive resist composition is a resin composed of only a repeating unit represented by the formula (3).   The positive resist according to claim 1, wherein the sulfonic acid generated from the compound (B) is perfluoroethanesulfonic acid, perfluoro-n-propanesulfonic acid, or perfluoroisopropanesulfonic acid. Composition.   The positive resist composition in any one of Claims 1-8 whose compound (B) is a compound represented by the following general formula (B1-1).

  In the general formula (B1-1), R _201b1 ~ R _203b1 Each independently represents an aryl group.
  Xb ^- Represents —SO of fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms. _Three It represents a sulfonate anion from which a hydrogen atom of H has been removed.   The positive resist composition according to claim 1, wherein the compound (B) is a compound represented by the following general formula (B1-2).

  In the general formula (B1-2), R _201b2 Represents an aryl group. R _202b2 And R _203b2 Are connected to each other to form an alkylene group.
  Xb ^- Represents —SO of fluorine-substituted alkanesulfonic acid having 2 or 3 carbon atoms. _Three It represents a sulfonate anion from which a hydrogen atom of H has been removed. Pattern forming method to form a resist film from the positive resist composition according to any one of claims 1 to 10, exposing the resist film, characterized by development.