JP4328588B2 - Positive resist composition and pattern forming method using the same - Google Patents

Description

  The present invention relates to a positive resist composition used in an ultramicrolithography process such as the manufacture of VLSI and high-capacity microchips and other photofabrication processes.

In recent years, the degree of integration of integrated circuits has been increasing, and in the manufacture of semiconductor substrates such as VLSI, processing of ultrafine patterns having a line width of less than half a micron has been required. In order to satisfy this need, the wavelength used by exposure apparatuses used in photolithography has become shorter, and now it is considered to use excimer laser light (XeCl, KrF, ArF, etc.) having a short wavelength among far ultraviolet rays. It is becoming.
A chemical amplification type resist is used for lithography pattern formation in this wavelength region.

  In general, chemically amplified resists can be broadly classified into three types, commonly called two-component systems, 2.5-component systems, and three-component systems. The two-component system combines a compound that generates an acid by photolysis (hereinafter referred to as a photoacid generator) and a binder resin. The binder resin is a resin having in its molecule a group (also referred to as an acid-decomposable group) that decomposes by the action of an acid and increases the solubility of the resin in an alkaline developer. The 2.5 component system further contains a low molecular weight compound having an acid-decomposable group in the two component system. A three-component system contains a photoacid generator, an alkali-soluble resin, and the low molecular weight compound.

The chemical amplification resist is suitable as a photoresist for irradiation with ultraviolet rays or far ultraviolet rays, but among them, it is necessary to cope with the required characteristics in use.
As a photoresist composition for an ArF light source, a resin in which an alicyclic hydrocarbon moiety is introduced has been proposed for the purpose of imparting dry etching resistance, but the system is extremely hydrophobic as an adverse effect of the introduction of the alicyclic hydrocarbon moiety. Therefore, it is difficult to develop with a tetramethylammonium hydroxide (hereinafter, TMAH) aqueous solution that has been widely used as a resist developer, and the resist is peeled off from the substrate during development. It can be seen.
In response to the hydrophobization of the resist, measures such as mixing an organic solvent such as isopropyl alcohol with the developer have been studied, and although some results are seen, the concern about the swelling of the resist film and the process become complicated. The problem is not necessarily solved. In the approach of improving the resist, many measures have been taken to supplement various hydrophobic alicyclic hydrocarbon sites by introducing hydrophilic groups.

Patent Document 1 (Japanese Patent Application Laid-Open No. 9-73173) discloses an alkali-soluble group protected with a structure containing an alicyclic group, and a structural unit that makes the alkali-soluble group dissociated by an acid and becomes alkali-soluble. A resist material using an acid-sensitive compound is described.
Patent Document 2 (Japanese Patent Application Laid-Open No. 11-119434) discloses a repeating unit having an alicyclic hydrocarbon as a low-cost resist material having high resolution, high sensitivity, and improved dry etching resistance, a lactone. A resist material using a resin containing a repeating unit having a structure is proposed.

Patent Document 3 (Japanese Patent Laid-Open No. 2000-292917) describes a resist composition using a mixture of a triarylsulfonium salt acid generator and a phenacylsulfonium salt acid generator.
Patent Document 4 (Japanese Patent Application Laid-Open No. 2001-294570) describes a resist composition containing a phenacylsulfonium salt.

JP-A-9-73173 JP 11-119434 A JP 2000-292917 A JP 2001-294570 A

  However, conventional positive resist compositions have not achieved sufficient results with respect to line edge roughness and pattern collapse performance in microphotofabrication using far ultraviolet light, particularly ArF excimer laser light.

  Accordingly, an object of the present invention is to provide a positive resist that can be suitably used in microphotofabrication using far ultraviolet light, particularly ArF excimer laser light, and has excellent line edge roughness performance and excellent pattern collapse performance. It is to provide a composition.

As a result of intensive studies on the constituent materials of the positive chemically amplified resist composition, the present inventors have found that the object of the present invention can be achieved by using a specific acid-decomposable resin, and have reached the present invention. .
That is, the above object is achieved by the following configuration.

(1) (A) Resin whose solubility in an alkali developer is increased by the action of an acid containing a repeating unit represented by the following general formula (Ia) and a repeating unit represented by the general formula (Ib), and (B ) A positive resist composition comprising a compound represented by the following general formula (I), (II) or (III):

In formulas (Ia) and (Ib), Ra ₁ independently represents a hydrogen atom or an alkyl group, and A represents a single bond .
In the formula (Ia), Ra ₁₁ represents an alkyl group having 1 to 4 carbon atoms, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with a carbon atom.
Wherein (Ib), Ra ₁₂ ~R ₁₄ each independently represent a hydrocarbon group, representing at least one alicyclic hydrocarbon group of Ra ₁₂ to Ra _14.

一般式（ＩＩＩ）中、
Ａｒは、アリール基又はヘテロ原子を含む芳香族基を表す。
Ｒ₆は、水素原子、シアノ基、アルキル基又はアリール基を表す。
Ｒ₇は、アルキル基又はアリール基を表す。
Ｙ₃及びＹ₄は、同じでも異なっていてもよく、アルキル基、アリール基、アラルキル基又はヘテロ原子を含む芳香族基を表す。Ｙ₃とＹ₄とが結合して環を形成してもよい。
ＡｒとＹ₃及びＹ₄の少なくとも一つが結合して環を形成してもよい。
ＡｒとＲ₆とが結合して環を形成してもよい。
また、Ａｒ、Ｒ₆若しくはＲ₇のいずれか又はＹ₃若しくはＹ₄のいずれかの位置で、連結基を介して結合し、一般式（ＩＩＩ）の構造を２つ以上有していてもよい。
Ｘ^-は、非求核性アニオンを表す。 In general formulas (I) and (II),
R _{1 to} R ₃ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or an alkoxy group.
R ₄ and R ₅ may be the same or different and each represents a hydrogen atom, a cyano group, an alkyl group, an aryl group, or an alkoxy group.
Y ₁ and Y ₂ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom.
n represents an integer of 1 to 4. When n is 2 or more, a plurality of R ₁ and R ₂ may be the same or different.
Any two or more of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ may be bonded to form a ring structure.
In addition, at any position of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ , they are bonded via a linking group and have two or more structures of the general formula (I) or (II). You may do it.
X ⁻ represents a non-nucleophilic anion.

In general formula (III),
Ar represents an aryl group or an aromatic group containing a hetero atom.
R ₆ represents a hydrogen atom, a cyano group, an alkyl group or an aryl group.
R ₇ represents an alkyl group or an aryl group.
Y ₃ and Y ₄ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom. Y ₃ and Y ₄ may combine to form a ring.
Ar may combine with at least one of Y ₃ and Y ₄ to form a ring.
Ar and R ₆ may combine to form a ring.
Further, they may be bonded via a linking group at any position of Ar, R ₆ or R ₇ or at any position of Y ₃ or Y ₄ and have two or more structures of the general formula (III). .
X ⁻ represents a non-nucleophilic anion.

(2) (B) The positive resist composition according to claim 1, wherein the compound represented by the general formula (III) is a compound represented by the following general formula (IV ′ ).

In general formula (IV ′), R8 to R12 may be the same or different and each represents a hydrogen atom, a nitro group, a halogen atom, an alkyl group, an alkoxy group, an alkyloxycarbonyl group, an aryl group, or an acylamino group.
At least two of R8 to R12 may be bonded to form a ring structure.
R13 represents a hydrogen atom, a cyano group, an alkyl group or an aryl group.
R14 represents an alkyl group or an aryl group.
Y5 and Y6 may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom.
Y5 and Y6 may combine to form a ring.
At least one of R8 to R12 may be bonded to at least one of Y5 and Y6 to form a ring.
At least one and R13 of R8~R12 may be bonded to form a ring.
Further, at any position of R8 to R14, or any position of Y5 or Y6, they may be bonded via a linking group to have two or more structures of the general formula (IV ′).
X- represents a non-nucleophilic anion.

一般式（IV）中、Ｒ ₁ a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。
Ｒａ ₁ 、Ｒｂ ₁ 、Ｒｃ ₁ 、Ｒｄ ₁ 、Ｒｅ ₁ 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、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。
（６） 樹脂（Ａ）が更に下記一般式（ＡＩ）で表される繰り返し単位を含有することを特徴とする上記（１）〜（５）のいずれか一項に記載のポジ型レジスト組成物。

一般式（ＡＩ）中、Ｒ _b0 は、水素原子、ハロゲン原子、又は炭素数１〜４の置換もしくは非置換のアルキル基を表す。Ａ’は、単結合、エーテル基、エステル基、カルボニル基、アルキレン基、又はこれらを組み合わせた２価の基を表す。Ｂ ₂ は、下記一般式（Ｖ−１）〜（Ｖ−４）のうちのいずれかで示される基を表す。

一般式（Ｖ−１）〜（Ｖ−４）において、Ｒ _1b 〜Ｒ _5b は、各々独立に水素原子、置換基を有していてもよい、アルキル基、シクロアルキル基又はアルケニル基を表す。Ｒ _1b 〜Ｒ _5b の内の２つは、結合して環を形成してもよい。
（７） 樹脂（Ａ）が更に下記一般式（ＡII）で表される繰り返し単位を含有することを特徴とする請求項１〜６のいずれか一項に記載のポジ型レジスト組成物。

一般式（ＡII）中、Ｒ ₁ cは、水素原子又はメチル基を表す。
Ｒ ₂ c〜Ｒ ₄ cは、各々独立に水素原子又は水酸基を表す。ただし、Ｒ ₂ c〜Ｒ ₄ cのうち少なくとも１つは水酸基を表す。
（８） （１）〜（７）のいずれかに記載のレジスト組成物に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。 (3) The positive resist composition as described in (1) or (2), further comprising (C) a fluorine-based and / or silicon-based surfactant.
(4) The positive resist composition as described in any one of (1) to (3), further comprising (D) an organic basic compound.
(5) The positive electrode according to any one of (1) to (4) above, wherein the resin (A) further contains a repeating unit having a lactone structure represented by the following general formula (IV): Type resist composition.

In general formula (IV), R ₁ a 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.
Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ and Re ₁ 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.
(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 following general formula (AI): .

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these. B ₂ represents a group represented by any one of the following general formulas (V-1) to (V-4).

In General Formulas (V-1) to (V-4), R _{1b to} R _5b each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, or an alkenyl group that may have a substituent. Two of R _{1b to} R _5b may combine to form a ring.
(7) Resin (A) contains the repeating unit further represented by the following general formula (AII), The positive resist composition as described in any one of Claims 1-6 characterized by the above-mentioned.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c represents a hydrogen atom or a hydroxyl group independently. Provided that at least one of R ₂ c to R ₄ c represents a hydroxyl group.
( 8 ) A pattern forming method comprising: forming a resist film from the resist composition according to any one of (1) to ( 7 ); and exposing and developing the resist film.

  The present invention can provide a positive resist composition having excellent line edge roughness performance and excellent pattern collapse performance. The positive resist composition of the present invention can be suitably used for microfabrication using far ultraviolet light, particularly ArF excimer laser light.

Hereinafter, the present invention will be described in detail.
The present invention has the structure described in the scope of claims for patent, but the following are also described for reference.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution 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).

[1] (A) A resin whose solubility in an alkaline developer is increased by the action of an acid (also referred to as “acid-decomposable resin”).

  The component (A) in the present invention, that is, a resin whose solubility in an alkaline developer is increased by the action of an acid, includes a repeating unit represented by the following general formula (Ia) and a repeating unit represented by the general formula (Ib). It is a resin to contain.

In formulas (Ia) and (Ib), Ra ₁ independently represents a hydrogen atom or an alkyl group, and A represents a linking group.
In the formula (Ia), Ra ₁₁ represents an alkyl group having 1 to 4 carbon atoms, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with a carbon atom.
Wherein (Ib), Ra ₁₂ ~Ra ₁₄ each independently represent a hydrocarbon group, representing at least one alicyclic hydrocarbon group of Ra ₁₂ to Ra _14.

The alkyl group for Ra ₁ is preferably an alkyl group having 1 to 4 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group). Ra ₁ is particularly preferably a hydrogen atom or a methyl group.
A represents a linking group, and generally comprises a single bond, an alkylene group, a substituted 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. It represents a single group selected from the group or a combination of two or more groups. The linking group as A preferably has 10 or less carbon atoms.
Examples of the alkylene group for A include groups represented by the following formulas.
− [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 may be a substituted alkyl group or an unsubstituted alkyl group, may be linear or branched, and is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, more preferably a methyl group. , Ethyl group, propyl group, isopropyl group. Examples of the substituent of the substituted alkyl group 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 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.

In formula (Ia), Ra ₁₁ represents an alkyl group having 1 to 4 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group). .

Wherein (Ib), Ra ₁₂ ~Ra ₁₄ each independently represent a hydrocarbon group, representing at least one alicyclic hydrocarbon group of Ra ₁₂ to Ra _14.

The hydrocarbon group other than the alicyclic hydrocarbon group represented by Ra _{12 to} Ra ₁₄ is preferably a linear or branched alkyl group having 1 to 15 carbon atoms (particularly preferably 1 to 4 carbon atoms).

The alicyclic hydrocarbon group in Ra _{12 to} Ra _{14 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, and a cyclododecanyl group.

  Examples of the substituent for these alicyclic hydrocarbon groups include an alkyl group, a halogen atom, a hydroxyl group, and an oxo group (═O). The alkyl group may be substituted or unsubstituted, may be linear or branched, and is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, more preferably a methyl group, an ethyl group, or a propyl group. And a substituent selected from the group consisting of an isopropyl group. Examples of the substituent of the substituted alkyl group 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.

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

  The (A) acid-decomposable resin of the present invention may further contain a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the following general formulas (pIII) to (pV).

(In the above formula, R ₁₅ and R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that any of R ₁₅ and R ₁₆ Or 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 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 is a fat Represents a cyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring. )

In the general formulas (pIII) to (pV), the alkyl group in R _{15 to} R ₂₅ may be either substituted or unsubstituted, and is 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 structures represented by the general formulas (pIII) to (pV) in the resin can be used for protecting alkali-soluble groups. Examples of the alkali-soluble group include various groups known in this technical field.
Specific examples include a carboxylic acid group, a sulfonic acid group, a phenol group, and a thiol group, and a carboxylic acid group and a sulfonic acid group are preferable.
Preferred examples of the alkali-soluble group protected by the structure represented by the general formulas (pIII) to (pV) in the resin include groups represented by the following general formulas (pIX) to (pXI).

Here, R _{15 to} R ₂₅ are the same as defined above.
In the resin, the repeating unit having an alkali-soluble group protected by the structure represented by the general formulas (pIII) to (pV) is preferably a repeating unit represented by the following general formula (pA).

Here, R represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A is the same as in formulas (Ia) and (Ib).
Ra represents any group of the above formulas (pIII) to (pV).

  Although the specific example of the monomer corresponding to the repeating structural unit represented by general formula (pA) below is given, it is not limited to these.

  The acid-decomposable resin of the present invention can further contain a repeating unit having a lactone structure represented by the following general formula (IV).

In general formula (IV), R ₁ a 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.
Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ and Re ₁ 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.

Examples of the alkyl group having 1 to 4 carbon atoms of Ra _{1 to} Re ₁ include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group. Can do.

In the general formula (IV), examples of the alkylene group for W ₁ include groups represented by the following formulae.
− [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 may be a substituted alkyl group or an unsubstituted alkyl group, may be linear or branched, and is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, more preferably a methyl group. Group, ethyl group, propyl group, isopropyl group. Examples of the substituent of the substituted alkyl group 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 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 further substituents in the alkyl group include a carboxyl group, an acyloxy group, a cyano group, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a substituted alkoxy group, an acetylamide group, an alkoxycarbonyl group, and an acyl group. Can be mentioned.
Here, the alkyl group may be a substituted alkyl group or an unsubstituted alkyl group, and examples thereof include a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclopentyl group. be able to. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. The alkoxy group may be a substituted alkoxy group or an unsubstituted alkoxy group, and examples of the substituent include 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 acyloxy group include an acetoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

  Specific examples of the repeating structural unit represented by the general formula (IV) are shown below, but are not limited thereto.

In the specific example of the general formula (IV), (IV-17) to (IV-36) are preferable because the exposure margin becomes better.
Further, as the structure of the general formula (IV), those having an acrylate structure are preferable from the viewpoint that the edge roughness becomes good.

  Moreover, you may contain the repeating unit which has group represented by either of the following general formula (V-1)-(V-4).

In General Formulas (V-1) to (V-4), R _{1b to} R _5b each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, or an alkenyl group that may have a substituent. Two of R _{1b to} R _5b may combine to form a ring.

In the general formulas (V-1) to (V-4), examples of the alkyl group in R _{1b to} R _5b include linear and branched alkyl groups, which may have a substituent.
The linear or branched alkyl group is preferably a linear or branched alkyl group having 1 to 12 carbon atoms, more preferably a linear or branched alkyl group having 1 to 10 carbon atoms. More preferably, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl It is a 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 3- to 8-membered rings such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring.
In the general formulas (V-1) to (V-4), R _{1b to} R _5b may be connected to any carbon atom constituting 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.

  Examples of the repeating unit having a group represented by general formulas (V-1) to (V-4) include a repeating unit represented by the following general formula (AI).

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. As a preferable substituent which the alkyl group of R _b0 may have, as a preferable substituent which the alkyl group as R _1b in the general formulas (V-1) to (V-4) may have. What was illustrated previously is mentioned.
Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R _b0 is preferably a hydrogen atom.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of the general formulas (V-1) to (V-4). In A ′, examples of the combined divalent group include those represented by the following formulae.

In the above formula, Rab and Rbb 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 may have a substituent, may be linear or branched, and is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, more preferably a methyl group, It is selected from an ethyl group, a propyl group, and an isopropyl group. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group 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. r1 represents an integer of 1 to 10, preferably an integer of 1 to 4. m represents an integer of 1 to 3, preferably 1 or 2.

  Although the specific example of the repeating unit represented by general formula (AI) is given to the following, it is not limited to these.

  Moreover, the acid-decomposable resin of the present invention can further contain a repeating unit represented by the following general formula (VI).

In the general formula (VI), A ₆ represents a single bond, an alkylene group, a cycloalkylene group, an ether group, a thioether group, a carbonyl group, or a group of two or more groups selected from the group consisting of ester groups.
R _6a represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyano group, or a halogen atom.

In the general formula (VI), examples of the alkylene group represented by A ₆ include groups represented by the following formulae.
-[C (Rnf) (Rng)] r-
In the above formula, Rnf and Rng 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 may have a substituent, may be linear or branched, and is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, more preferably a methyl group, It is selected from an ethyl group, a propyl group, and an isopropyl group. Examples of the substituent of the substituted alkyl group 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 halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r is an integer of 1-10.
In the general formula (VI), examples of the cycloalkylene group represented by A ₆ include those having 3 to 10 carbon atoms, such as a cyclopentylene group, a cyclohexylene group, and a cyclooctylene group.

The bridged alicyclic ring containing Z ₆ may have a substituent. Examples of the substituent include a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms), an alkoxycarbonyl group (preferably having 1 to 5 carbon atoms), an acyl group (for example, a formyl group and a benzoyl group), an acyloxy group ( For example, a propylcarbonyloxy group, a benzoyloxy group), an alkyl group (preferably having a carbon number of 1 to 4), a carboxyl group, a hydroxyl group, an alkylsulfonylcarbamoyl group (—CONHSO ₂ CH ₃ etc.) can be mentioned. In addition, the alkyl group as a substituent may be further substituted with a hydroxyl group, a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms), or the like.

In the general formula (VI), the oxygen atom of the ester group bonded to A ₆ may be bonded at any position of the carbon atom constituting the bridged alicyclic ring structure containing Z ₆ .

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

  Furthermore, you may contain the repeating unit which has group represented by the following general formula (VII).

In general formula (VII), R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.

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

  Examples of the repeating unit having a group represented by the general formula (VII) include a repeating unit represented by the following general formula (AII).

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.

  Although the specific example of the repeating unit which has a structure represented by general formula (AII) below is given, it is not limited to these.

  In addition to the above repeating structural units, the acid-decomposable resin as component (A) includes dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required characteristics of resist, resolving power and heat resistance. Various repeating structural units can be contained for the purpose of adjusting properties, sensitivity and the like.

Examples of such repeating structural units 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. can be mentioned.

Specifically, the following monomers can be mentioned.
Acrylic acid esters (preferably alkyl acrylates having an alkyl group with 1 to 10 carbon atoms):
Methyl acrylate, ethyl acrylate, propyl acrylate, amyl acrylate, cyclohexyl acrylate, ethyl hexyl acrylate, octyl acrylate, tert-octyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate 2, 2-dimethylhydroxy Propyl acrylate, 5-hydroxypentyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, and the like.

Methacrylic acid esters (preferably alkyl methacrylate having 1 to 10 carbon atoms in the alkyl group):
Methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 2 2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate and the like.

Acrylamides:
Acrylamide, N-alkylacrylamide (alkyl group having 1 to 10 carbon atoms, such as methyl group, ethyl group, propyl group, butyl group, t-butyl group, heptyl group, octyl group, cyclohexyl group, hydroxyethyl group, etc. N, N-dialkylacrylamide (alkyl groups having 1 to 10 carbon atoms such as methyl, ethyl, butyl, isobutyl, ethylhexyl, cyclohexyl, etc.), N-hydroxy Ethyl-N-methylacrylamide, N-2-acetamidoethyl-N-acetylacrylamide and the like.

Methacrylamide:
Methacrylamide, N-alkylmethacrylamide (alkyl groups having 1 to 10 carbon atoms, such as methyl, ethyl, t-butyl, ethylhexyl, hydroxyethyl, cyclohexyl, etc.), N, N -Dialkylmethacrylamide (there are alkyl groups such as ethyl group, propyl group, butyl group), N-hydroxyethyl-N-methylmethacrylamide and the like.

Allyl compounds:
Allyl esters (for example, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, etc.), allyloxyethanol and the like.

Vinyl ethers:
Alkyl vinyl ethers (for example, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethyl hexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2, 2-dimethylpropyl vinyl ether, 2-ethylbutyl vinyl ether, hydroxyethyl vinyl ether, Diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether and the like.

Vinyl esters:
Vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valerate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxyacetate, vinyl butoxyacetate, vinyl acetoacetate, vinyl lactate, vinyl -Β-phenylbutyrate, vinylcyclohexylcarboxylate and the like.

Dialkyl itaconates:
Dimethyl itaconate, diethyl itaconate, dibutyl itaconate, etc.
Dialkyl esters or monoalkyl esters of fumaric acid; dibutyl fumarate and the like.

  Others include crotonic acid, itaconic acid, maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, maleilonitrile and the like.

  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 etching 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.

In the acid-decomposable resin, the total amount of the repeating unit represented by the general formula (Ia) and the repeating unit represented by the general formula (Ib) is preferably 30 to 70 mol%, more preferably 35%, based on all repeating structural units. It is -65 mol%, More preferably, it is 40-60 mol%.
The range of the repeating unit represented by the general formula (Ia): the repeating unit (molar ratio) represented by the general formula (Ib) is generally 99/1 to 1/99, preferably 90/10 to 10 / 90, more preferably 80/20 to 20/80.
In the acid-decomposable resin, the content of the repeating unit having a partial structure containing an alicyclic hydrocarbon represented by general formulas (pIII) to (pV) is preferably 30 to 70 mol% in all repeating structural units, More preferably, it is 35-65 mol%, More preferably, it is 40-60 mol%.
The total content of the repeating units of the general formulas (IV) to (VII) is preferably 5 to 70 mol%, more preferably 10 to 65 mol%, still more preferably 15 to 60 mol% in all repeating structural units. It is.
A repeating unit having an acid-decomposable group containing a repeating unit represented by the general formula (Ia) or (Ib) or a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by (pIII) to (pV) The content of units is preferably 30 to 70 mol%, more preferably 35 to 65 mol%, still more preferably 40 to 60 mol% in all repeating structural units.

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

The weight average molecular weight of the resin according to the present invention is preferably 1,000 to 200,000 as a polystyrene conversion value by the GPC method. A weight average molecular weight of 1,000 or more is preferable from the viewpoint of heat resistance and dry etching resistance, and 200,000 or less is preferable from the viewpoint of developability and film-forming property. The composition of the present invention is ArF exposure. When used, the resin preferably does not have an aromatic ring from the viewpoint of transparency to ArF light.
Further, it is preferable that the resin main chain does not have an alicyclic group from the viewpoint of excellent contact hole detachability and a significant improvement in defocus latitude (acceptable range of defocus).

  In the positive photoresist composition for deep ultraviolet exposure according to the present invention, the blending amount of all the resins according to the present invention in the entire composition is preferably 40 to 99.99% by mass in the total resist solid content, more preferably. It is 50-99.97 mass%.

[2] (B) Acid generator The component (B) in the present invention is a compound represented by the general formula (I), (II) or (III), and generates an acid upon irradiation with actinic rays or radiation. It is a compound that generates acid by actinic rays such as infrared rays, visible light, ultraviolet light, and far ultraviolet light, charged particle beams such as X-rays and electron beams, heat, ultrasonic waves, and the like.

(B-1) Compound represented by general formula (I) or (II) First, the compound represented by general formula (I) or (II) is demonstrated.

In general formulas (I) and (II),
R _{1 to} R ₃ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or an alkoxy group.
R ₄ and R ₅ may be the same or different and each represents a hydrogen atom, a cyano group, an alkyl group, an aryl group, or an alkoxy group.
Y ₁ and Y ₂ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom.
n represents an integer of 1 to 4. When n is 2 or more, a plurality of R ₁ and R ₂ may be the same or different.
Any two or more of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ may be bonded to form a ring structure.
In addition, at any position of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ , they are bonded via a linking group and have two or more structures of the general formula (I) or (II). You may do it.
X ⁻ represents a non-nucleophilic anion.

In general formulas (I) and (II), R _{1 to} R ₃ may be the same or different, and may have a hydrogen atom or a substituent, an alkyl group, an alkenyl group, an aryl group, or an alkoxy group. Represents. R ₄ and R ₅ may be the same or different and each represents a hydrogen atom, a cyano group, or an alkyl group, aryl group or alkoxy group which may have a substituent. Y ₁ and Y ₂ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom, which may have a substituent. n represents an integer of 1 to 4. When n is 2 or more, a plurality of R ₁ and R ₂ may be the same or different. Any two or more of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ may be bonded to form a ring structure. In addition, at any position of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ , they are bonded via a linking group and have two or more structures of the general formula (I) or (II). You may do it. X ⁻ represents a non-nucleophilic anion.

The alkyl groups of R _{1 to} R ₅ , Y ₁ and Y ₂ may have a substituent, and preferably an alkyl group having 1 to 10 carbon atoms, such as a methyl group, an ethyl group, a propyl group, Examples thereof include linear, branched and cyclic alkyl groups such as n-butyl group, sec-butyl group, t-butyl group, pentyl group, cyclopentyl group, hexyl group and cyclohexyl group. The alkyl group may have an oxygen atom, a sulfur atom, a carbonyl group or the like in the alkyl chain.
The aryl group of R _{1 to} R ₅ , Y ₁ and Y ₂ may have a substituent, and preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, a naphthyl group, etc. Can be mentioned.

The alkenyl group of R _{1 to} R ₃ may have a substituent and is preferably an alkenyl group having 2 to 6 carbon atoms, such as a vinyl group, propenyl group, allyl group, butenyl group, pentenyl group, hexenyl. Group, cyclopentenyl group, cyclohexenyl group, 3-oxocyclopentenyl group, 3-oxocyclohexenyl group and the like.

The alkoxy group of R _{1 to} R ₅ may have a substituent, and is preferably an alkoxy group having 1 to 8 carbon atoms. For example, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, butoxy Group, pentoxy group, allyloxy group, octoxy group and the like.

The aralkyl group of Y ₁ and Y ₂ is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a cumyl group.

The aromatic group containing a hetero atom represents a group having a hetero atom, for example, a nitrogen atom, an oxygen atom, a sulfur atom, etc. in an aromatic group such as an aryl group having 4 to 14 carbon atoms.
Examples of the aromatic group containing a hetero atom of Y ₁ and Y ₂ include heterocyclic aromatic hydrocarbon groups such as furan, thiophene, pyrrole, pyridine, and indole.

As the ring structure formed by combining two or more of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ , for example, R ₁ or R ₂ and R ₃ are bonded. A ring structure formed, a ring structure formed by combining R ₁ or R ₂ and R ₄ or R ₅ , a ring structure formed by combining R ₃ and R ₄ or R ₅ , R ₁ ; A ring structure formed by combining R ₂ and R ₄ or R ₅ ; a ring structure formed by combining R ₁ , R ₂ , R ₃ and R ₄ or R ₅ ; Y ₁ ; Y ₂ and can be exemplified ring structures such as to form together with S ⁺ in the general formula bonded (I) or (II).

When R ₁ or R ₂ and R ₃ are bonded to form a ring structure, the group formed by combining R ₁ or R ₂ and R ₃ is preferably a heteroatom in the chain. And an alkylene group having 1 to 10 carbon atoms, such as methylene group, ethylene group, propylene group, butylene group, pentylene group, and hexylene group.

When R ₁ or R ₂ and R ₄ or R ₅ combine to form a ring structure, the group formed by combining R ₁ or R ₂ and R ₄ or R ₅ includes, for example, alkylene Group, carbonyl group and the like. As an alkylene group, Preferably, a C1-C10 alkylene group, for example, a methylene group, ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group etc. can be mentioned.

When R ₃ and R ₄ or R ₅ combine to form a ring structure, the group formed by combining R ₃ and R ₄ or R ₅ preferably has 1 to 10 carbon atoms. And an alkylene group such as a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group.

A ring structure formed by combining R ₁ , R ₂ and R ₄ or R ₅ and a ring structure formed by combining R ₁ , R ₂ , R ₃ and R ₄ or R ₅ May include, for example, a bicyclic fused ring structure having 5 to 15 carbon atoms.

Y ₁ and Y ₂ may combine to form a ring structure together with S ⁺ in the general formula (I) or (II).
In this case, examples of the group formed by combining Y ₁ and Y ₂ include an alkylene group having 4 to 10 carbon atoms, preferably a butylene group, a pentylene group, and a hexylene group, and particularly preferably a butylene group and a pentylene group. Can be mentioned.
Further, the ring formed by combining Y ₁ and Y ₂ together with S ⁺ in the general formula (I) or (II) may contain a hetero atom.

Examples of the substituent that each of the alkyl group, alkenyl group, aryl group, aralkyl group, aromatic group, and cyclic structure may have, for example, a nitro group, a halogen atom, a carboxyl group, a hydroxyl group, an oxo group, an amino group Group, cyano group, alkoxy group (preferably having 1 to 5 carbon atoms) and the like. Further, the aryl group and aralkyl group may be substituted with an alkyl group (preferably having 1 to 5 carbon atoms).
Moreover, as a substituent of an alkyl group, a halogen atom, a hydroxyl group, and an alkoxy group are preferable.

Examples of the non-nucleophilic anion of X ⁻ include a sulfonate anion, a carboxylate anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methide anion.
A non-nucleophilic anion is an anion that has an extremely low ability to cause a nucleophilic reaction, and is an anion that can suppress degradation over time due to an intramolecular nucleophilic reaction. This improves the temporal stability of the resist.
Examples of the sulfonate anion include an alkyl sulfonate anion, an aryl sulfonate anion, and a camphor sulfonate anion.
Examples of the carboxylate anion include an alkylcarboxylate anion, an arylcarboxylate anion, and an aralkylcarboxylate anion.

The alkyl group in the alkylsulfonate anion is preferably an alkyl group having 1 to 30 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a pentyl group. , Neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, cyclo Examples thereof include a propyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornyl group, and a boronyl group.
The aryl group in the aryl sulfonate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

The alkyl group and aryl group in the alkyl sulfonate anion and aryl sulfonate anion may have a substituent.
Examples of the substituent include a halogen atom, an alkyl group, an alkoxy group, and an alkylthio group.

Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.
Examples of the alkyl group include preferably an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a pentyl group, and a neopentyl group. Hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, etc. it can.
As an alkoxy group, Preferably a C1-C5 alkoxy group, for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. can be mentioned, for example.
As the alkylthio group, for example, preferably an alkylthio group having 1 to 20 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, an isopropylthio group, an n-butylthio group, an isobutylthio group, a sec-butylthio group, a pentylthio group, Neopentylthio group, hexylthio group, heptylthio group, octylthio group, nonylthio group, decylthio group, undecylthio group, dodecylthio group, tridecylthio group, tetradecylthio group, pentadecylthio group, hexadecylthio group, heptadecylthio group, octadecylthio group, nonadecylthio group Group, eicosylthio group and the like. The alkyl group, alkoxy group, and alkylthio group may be further substituted with a halogen atom (preferably a fluorine atom).

Examples of the alkyl group in the alkylcarboxylate anion include the same alkyl groups as in the alkylsulfonate anion.
Examples of the aryl group in the arylcarboxylate anion include the same aryl groups as in the arylsulfonate anion.
The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 6 to 12 carbon atoms, such as a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, and a naphthylmethyl group.

  The alkyl group, aryl group and aralkyl group in the alkylcarboxylate anion, arylcarboxylate anion and aralkylcarboxylate anion may have a substituent. Examples of the substituent are the same as those in the arylsulfonate anion. A halogen atom, an alkyl group, an alkoxy group, an alkylthio group, etc. can be mentioned.

  The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methide anion is preferably an alkyl group having 1 to 5 carbon atoms, for example, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl. Group, sec-butyl group, pentyl group, neopentyl group and the like. These alkyl groups may have a substituent, and examples of the substituent include a halogen atom, an alkoxy group, and an alkylthio group.

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

As the non-nucleophilic anion of X ⁻ , an alkanesulfonic acid anion in which the α-position of the sulfonic acid is substituted with a fluorine atom, an arylsulfonic acid anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group having a fluorine atom A bis (alkylsulfonyl) imide anion substituted with a tris (alkylsulfonyl) methide anion substituted with a fluorine atom in the alkyl group, particularly preferably a perfluoroalkanesulfonic acid anion having 1 to 8 carbon atoms, most preferably Nonafluorobutane sulfonate anion and perfluorooctane sulfonate anion.

In the general formula (I) or (II), at any position of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ , a bond is formed through a linking group, and the general formula (I) or ( It may have two or more structures of II).

The acid generator (B) represented by the general formula (I) or (II) is characterized by having a double bond conjugated with a carbonyl group, whereby the excited state is stabilized and the acid generating ability is improved. improves.
When R ₁ or R ₂ and R ₄ or R ₅ are bonded to form a ring structure, or R ₃ and R ₄ or R ₅ are bonded to form a ring structure, the steric structure is carbonyl. The π ^* orbital and the C−S ⁺ σ orbital are fixed so that they are parallel to each other, and the acid generating ability is further improved.
In the general formula (I) or (II), n = 1 or 2 is preferable, and n = 1 is particularly preferable.
It is preferable that any two of R _{1 to} R ₅ are bonded via an alkylene group to form a 5- to 7-membered ring or a polycyclic ring structure containing a 5 to 7-membered ring.
R ₄ and R ₅ are preferably a hydrogen atom or an alkyl group.
Y ₁ and Y ₂ are preferably bonded via an alkylene group to form a 5- to 7-membered ring.

  Although the preferable specific example of a compound represented by the said general formula (I) or (II) is shown below, this invention is not limited to this.

  The compound of the said general formula (I) or (II) can be used individually by 1 type or in combination of 2 or more types.

The compound represented by the general formula (I) or (II) is obtained by subjecting the corresponding unsaturated ketone compound to silyl enol etherification with trimethylsilyl chloride or the like under basic conditions, and then reacting with a sulfoxide to obtain a sulfonium salt, which is then subjected to salt exchange. Can be synthesized.
In addition, the compound represented by the general formula (I) or (II) is obtained by halogenating the α-position or allyl position of the ketone of the corresponding unsaturated ketone compound with bromine or copper bromide, and the like. Can be synthesized by reacting a sulfide compound with a non-catalyst or in the presence of a silver catalyst to form a sulfonium salt, followed by salt exchange.

  The content of the compound represented by the general formula (I) or (II) in the resist composition of the present invention is preferably 0.1 to 20% by mass, more preferably 0.8%, based on the solid content of the composition. It is 5-10 mass%, More preferably, it is 1-7 mass%.

(B-2) Compound represented by general formula (III) Next, the compound represented by general formula (III) is demonstrated.

In general formula (III),
Ar represents an aryl group or an aromatic group containing a hetero atom.
R ₆ represents a hydrogen atom, a cyano group, an alkyl group or an aryl group.
R ₇ represents an alkyl group or an aryl group.
Y ₃ and Y ₄ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom. Y ₃ and Y ₄ may combine to form a ring.
Ar may combine with at least one of Y ₃ and Y ₄ to form a ring.
Ar and R ₆ may combine to form a ring.
Further, they may be bonded via a linking group at any position of Ar, R ₆ or R ₇ or at any position of Y ₃ or Y ₄ and have two or more structures of the general formula (III). .
X ⁻ represents a non-nucleophilic anion.

The compound represented by the general formula (III) is preferably a compound represented by the following general formula (IV ′) .

In general formula (III), the aryl group of Ar is preferably an aryl group having 6 to 18 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthracenyl group, and a phenyl group and a naphthyl group are preferable. A phenyl group is more preferable.
The aromatic group containing a hetero atom of Ar is preferably a group having a hetero atom such as a nitrogen atom, an oxygen atom, or a sulfur atom in an aromatic group such as an aryl group having 6 to 18 carbon atoms.

In general formula (IV ′) , R _{8 to} R ₁₂ may be the same or different and each represents a hydrogen atom, a nitro group, a halogen atom, an alkyl group, an alkoxy group, an alkyloxycarbonyl group, an aryl group, or an acylamino group. . At least two of R _{8 to} R ₁₂ may be bonded to form a ring structure. R ₁₃ and R ₁₄ have the same meanings as R ₆ and R _{7 in} formula (III), respectively.
Y ₅ and Y ₆ have the same meanings as Y ₃ and Y _{4 in} the general formula (III), respectively. Y ₅ and Y ₆ may combine to form a ring. At least one of R _{8 to} R ₁₂ may be bonded to at least one of Y ₅ and Y ₆ to form a ring. At least one of R _{8 to} R ₁₂ and R ₁₃ may combine to form a ring. Further, at any position of R _{8 to} R ₁₄ or at any position of Y ₅ or Y ₆ , they may be bonded via a linking group to have two or more structures of the general formula (IV ′) . X ⁻ represents a non-nucleophilic anion.

In general formula (III) and general formula (IV ′) , the alkyl group in R ₆ , R ₇ , R _{8 to} R _{14 and} the alkyl group in the acylamino group are preferably alkyl groups having 1 to 20 carbon atoms. Methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, t-butyl group, cyclobutyl group, pentyl group, neopentyl group, cyclopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group And linear, branched and cyclic alkyl groups such as nonyl group and decyl group.
The alkoxy group in the alkoxy group of R _{8 to} R ₁₂ and the alkyloxycarbonyl group is preferably an alkoxy group having 1 to 10 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group. Group, cyclohexyloxy group, heptyloxy group, octyloxy group, nonyloxy group, decyloxy group and the like.
The aryl group of R ₆ , R ₇ , R _{8 to} R ₁₄ is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group, a tolyl group, and a naphthyl group.
Examples of the halogen atom for R _{8 to} R ₁₂ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The alkyl group of Y _{3 to} Y ₆ is preferably an alkyl group having 1 to 30 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, and a t-butyl group. Examples thereof include linear or branched alkyl groups and cyclic alkyl groups such as cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, and boronyl group.
The aryl group represented by Y _{3 to} Y ₆ is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group, a tolyl group, and a naphthyl group.
The aralkyl group of Y _{3 to} Y ₆ is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a cumyl group.
The aromatic group containing a hetero atom of Y _{3 to} Y ₆ is preferably a group having a hetero atom, for example, a nitrogen atom, an oxygen atom, a sulfur atom, etc. in an aromatic group such as an aryl group having 6 to 14 carbon atoms, Examples thereof include heterocyclic aromatic hydrocarbon groups such as furan, thiophene, pyrrole, pyridine, and indole.

Ar may have two or more substituents, and at least two of them may be bonded to form a ring structure.
In this case, the group formed by combining at least two substituents is preferably an alkylene group having 4 to 10 carbon atoms, and examples thereof include a butylene group, a pentylene group, and a hexylene group.

At least two members out of R _{8 to} R ₁₂ may combine to form a ring structure.
In this case, the group formed by combining at least two of R _{8 to} R ₁₂ is preferably an alkylene group having 4 to 10 carbon atoms, and examples thereof include a butylene group, a pentylene group, and a hexylene group. These alkylene groups may contain heteroatoms.

Y ₃ and Y ₄ , and Y ₅ and Y ₆ may combine to form a ring together with S ⁺ in general formula (III) and general formula (IV ′) .
In this case, examples of the group formed by combining Y ₃ and Y ₄ and Y ₅ and Y ₆ include, for example, an alkylene group having 4 to 10 carbon atoms, preferably a butylene group, a pentylene group, a hexylene group, Preferred examples include a butylene group and a pentylene group. Further, the formed ring may contain a hetero atom.

Each of the above groups may not further have a substituent, or may have a substituent. Examples of the substituent that the aryl group, alkyl group, alkoxy group, alkoxycarbonyl group, aralkyl group and the like may have include, for example, a nitro group, a halogen atom, a carboxyl group, a hydroxyl group, an amino group, a cyano group, an alkoxy group ( Preferably 1 to 5 carbon atoms, an alkyl group (preferably 1 to 20 carbon atoms), an aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyloxy group (preferably 2 to 7 carbon atoms), etc. Can do.
As the substituent of the alkyl group, a halogen atom is preferable, and a fluorine atom is particularly preferable.

Ar may be bonded to at least one of Y ₃ or Y ₄ to form a ring, or Ar and R ₆ may be bonded to form a ring.
In this case, the group formed by combining at least one of Ar and Y ₃ or Y ₄ and the group formed by combining Ar and R ₆ are preferably alkylene groups having 1 to 10 carbon atoms. Examples include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group. As the group formed by combining Ar and R ₆ , a carbonyl group is also preferable.

It may be bonded via a linking group at any position of Ar, R ₆ , R ₇ , or any position of Y ₃ or Y ₄ and may have two or more structures of the general formula (III). .

It may be bonded via a linking group at any position of R _{8 to} R ₁₄ , or any position of Y ₅ or Y ₆ , and may have two or more structures of the general formula (IV ′) .

At least one of R _{8 to} R ₁₂ and at least one of Y ₅ or Y ₆ may be bonded to form a ring, or at least one of R _{8 to} R ₁₂ and R ₁₃ may be bonded to form a ring. It may be formed.
In this case, as a group formed by bonding at least one of R _{8 to} R ₁₂ and at least one of Y ₅ or Y ₆ and a group formed by bonding at least one of R _{8 to} R ₁₂ and R ₁₃ , The alkylene group having 1 to 10 carbon atoms is preferable, and examples thereof include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, and a hexylene group. Moreover, as a group formed by bonding at least one of R _{8 to} R ₁₂ and R ₁₃ , a carbonyl group is also preferable.

Component (B) does not have a hydrogen atom in R ₇ , thereby improving optical resolution and improving sensitivity. The component (B) is preferably such that both R ₆ and R ₇ are alkyl groups, or R ₇ is an alkyl group having 2 to 20 carbon atoms, more preferably R ₇ is 4 carbon atoms. It is an alkyl group of ˜20. Further, when Ar and R ₆ are bonded to form a ring, R ₇ is preferably an alkyl group having 1 to 20 carbon atoms.

Examples of the non-nucleophilic anion of X ⁻ include the same as those in the general formulas (I) and (II).

  Although the preferable specific example of a compound represented by the said general formula (III) of this invention below is shown, this invention is not limited to these.

  The compound of general formula (III) can be used individually by 1 type or in combination of 2 or more types.

  The compound represented by the general formula (III) is prepared by reacting a corresponding acylbenzene derivative with a trialkylsilyl halide under basic conditions to form a silyl enol ether, and reacting this with a sulfoxide to synthesize a sulfonium skeleton. Can be obtained by salt exchange with the corresponding anion. As another synthesis method, a method in which a corresponding phenacyl halide and a sulfide compound are reacted in the presence of a non-catalyst or a silver catalyst to synthesize a sulfonium skeleton and salt-exchange it with the corresponding anion can be mentioned.

  The content of the compound represented by the general formula (III) in the resist composition of the present invention is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, based on the solid content of the composition. %, More preferably 1 to 7% by mass.

  As the component (B) of the present invention, the compound represented by the general formula (I) or (II) and the compound represented by the general formula (III) may be used alone or in combination. When used in combination, the total amount used is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and still more preferably 1 to 7%, based on the solid content of the total resist composition. % By mass.

(B) Acid generating compound that can be used in combination other than component In the present invention, in addition to component (B), a compound that decomposes upon irradiation with actinic rays or radiation to generate an acid may be used in combination.
The amount of the acid generator that can be used in combination with the component (B) of the present invention is usually 100/0 to 20/80, preferably 100/0, in a molar ratio (component (B) / other acid generator). 40/60, more preferably 100/0 to 50/50.
In particular, when an acid generator having an aromatic ring structure is used in combination, the amount used is preferably 60% or less, more preferably 50% or less of the total acid generator in mass ratio.
Examples of such acid generators that can be used in combination include photocation polymerization photoinitiators, photoradical polymerization photoinitiators, dye photodecolorants, photochromic agents, and actives used in microresists. Known compounds that generate an acid upon irradiation with light or radiation and mixtures thereof can be appropriately selected and used.

Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.
Particularly preferred are sulfonium salts, and triarylsulfonium salts and sulfonium salts having a 2-oxoalkyl group are most preferred.

  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 as described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Among the compounds that can be used in combination with an active ray or radiation to generate an acid upon decomposition, compounds represented by the following general formulas (ZI), (ZII), and (ZIII) are exemplified. Can do.

In the general formula (Z1), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of X ^{− in} formula (I).

The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.
The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (Z1-1) and (Z1-2) described later.

In addition, the compound which has two or more structures represented by general formula (Z1) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (Z1) is at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (Z1) It may be a compound.

  Further preferred examples of the component (Z1) include compounds (Z1-1) and (Z1-2) described below.

Compound (Z1-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (Z1), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
Arylsulfonium compound, all of R ₂₀₁ to R ₂₀₃ may be an aryl group or a part of R ₂₀₁ to R ₂₀₃ may be an aryl group with the remaining being an alkyl group.
Examples of the arylsulfonium compound include a triarylsulfonium compound, a diarylalkylsulfonium compound, and an aryldialkylsulfonium compound.
The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group that the arylsulfonium compound has as necessary is preferably a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec. -Butyl group, t-butyl group, cyclopropyl group, cyclobutyl group, cyclohexyl group and the like can be mentioned.
Aryl group R ₂₀₁ to R _203, an alkyl group, an alkyl group (for example, 1 to 15 carbon atoms), an aryl group (e.g., carbon number 6 to 14), an alkoxy group (for example, 1 to 15 carbon atoms), a halogen atom, You may have a hydroxyl group and a phenylthio group as a substituent. Preferred substituents are linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, most preferably alkyl groups having 1 to 4 carbon atoms, It is 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 (Z1-2) will be described.
Compound (Z1-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (Z1) each independently represents an organic group not containing an aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.
The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, an allyl group or a vinyl group, more preferably a linear or branched 2-oxoalkyl group and 2-oxocycloalkyl group, an alkoxycarbonylmethyl group, Most preferred is a linear or branched 2-oxoalkyl group.

The alkyl group and cycloalkyl group as R _{201 to} R ₂₀₃ may have a substituent, and the alkyl group may be linear or branched, and is preferably a straight chain having 1 to 10 carbon atoms. Examples thereof include a chain or branched alkyl group (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group) and a cyclic alkyl group having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group). More preferably, it is a 2-oxoalkyl group or an alkoxycarbonylmethyl group, and the 2-oxoalkyl group may be linear, branched or cyclic, and preferably at the 2-position of the above alkyl group> Mention may be made of groups having C═O. The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.
Two members out of R _{201 to} R ₂₀₃ may combine to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

In formula (ZII), (ZIII), R 204 ~R 207 each independently represents an alkyl group which may have an optionally substituted aryl group or a substituent.
Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group.
The alkyl group as R _{204 to} R ₂₀₇ may be linear, branched or cyclic, and is preferably a linear or branched alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group). Group, butyl group, pentyl group) and cyclic alkyl groups having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group).
Examples of the substituent that each group of R _{204 to} R ₂₀₇ may further have include an alkyl group (eg, having 1 to 15 carbon atoms), an aryl group (eg, having 6 to 15 carbon atoms), and an alkoxy group (eg, carbon Mathematical formulas 1 to 15), halogen atoms, hydroxyl groups, phenylthio groups and the like.
X <-> represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anions as X <-> in the general formulas (I) and (II).

  Examples of particularly preferable compounds among the compounds that are decomposed by irradiation with actinic rays or radiation that may be used in combination are listed below.

[3] Other additives In the positive resist composition of the present invention, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer, a surfactant, a photosensitizer, an organic basic compound, and A compound or the like that promotes solubility in a developer can be contained.

(C) Fluorine-based and / or silicon-based surfactant The positive resist composition of the present invention contains at least the above-mentioned components (A) to (B), but further includes (C) a fluorine-based and / or silicon-based interface. It is preferable to contain any one of activators (a fluorosurfactant and a silicon surfactant, a surfactant containing both a fluorine atom and a silicon atom), or two or more thereof.
When the positive resist composition of the present invention contains the above-mentioned (C) 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.
As these (C) surfactants, for example, JP-A 62-36663, JP-A 61-226746, JP-A 61-226745, JP-A 62-170950, JP 63-3345, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, JP-A-2002-277862, US Pat. No. 5,405,720. , No. 5,360,692, No. 5,529,881, No. 5,296,330, No. 5,436,098, No. 5,576,143, No. 5,294,511, No. 5,824,451 The following commercially available surfactants can also be used as they are.
Examples of commercially available surfactants that can be used include EFTOP EF301 and EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430 and 431 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189, and R08. (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical Co., Ltd.), etc. Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, the surfactant is derived from a fluoroaliphatic compound produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. 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). It may be a unit having different chain lengths in the same chain length, such as a block linked body) or a poly (block linked body of oxyethylene and oxypropylene) group. 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.

  (C) The amount of the 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 positive resist composition (excluding the solvent).

  A preferable organic basic compound (D) that can be used in the present invention is a compound having a stronger basicity than phenol. Of these, nitrogen-containing basic compounds are preferred.

Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² are each independently a hydrogen atom, an alkyl or cycloalkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, Here, R ²⁵¹ and R ²⁵² may combine with each other to form a ring. The alkyl group may be unsubstituted or substituted, and the alkyl group having a substituent is preferably an aminoalkyl group having 1 to 6 carbon atoms or a hydroxyalkyl group having 1 to 6 carbon atoms. .

(Wherein R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ each independently represents an alkyl group having 1 to 6 carbon atoms)
Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms of different chemical environments in one molecule, and particularly preferably both a substituted or unsubstituted amino group and a ring structure containing a nitrogen atom. It is a compound containing. Preferred examples include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazole, substituted or unsubstituted Pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted amino Examples include morpholine and substituted or unsubstituted aminoalkylmorpholine. Preferred substituents are amino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxyl group and cyano group.

  Preferred specific examples of the nitrogen-containing basic compound include guanidine, 1,1-dimethylguanidine, 1,1,3,3, -tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2- Dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4- Amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2- Minopiperidine, 1- (2-aminoethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5 Methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N- (2-aminoethyl) morpholine, 1,5-diazabicyclo [ 4.3.0] Nona-5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,4-diazabicyclo [2.2.2] octane, 2,4,5- Triphenylimidazole, N-methylmorpholine, N-ethylmorpholine, N-hydroxyethylmorpholine, N-benzylmorpholine, cyclohex Examples thereof include tertiary morpholine derivatives such as silmorpholinoethylthiourea (CHMETU), hindered amines described in JP-A-11-52575 (for example, those described in the publication [0005]), and the like. Absent.

Particularly preferred examples are 1,5-diazabicyclo [4.3.0] non-5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,4-diazabicyclo [2. 2.2] Octane, 4-dimethylaminopyridine, hexamethylenetetramine, 4,4-dimethylimidazoline, pyrroles, pyrazoles, imidazoles, pyridazines, pyrimidines, tertiary morpholines such as CHMETU, bis (1, And hindered amines such as 2,2,6,6-pentamethyl-4-piperidyl) sebagate.
Among them, 1,5-diazabicyclo [4.3.0] non-5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,4-diazabicyclo [2.2.2] Octane, 4-dimethylaminopyridine, hexamethylenetetramine, CHMETU, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebagate are preferred.

  These nitrogen-containing basic compounds are used alone or in combination of two or more. The usage-amount of a nitrogen-containing basic compound is 0.001-10 mass% normally with respect to solid content of the whole composition of the photosensitive resin composition, Preferably it is 0.01-5 mass%. The amount of 0.001% by mass or more is preferable in terms of the effect of adding the nitrogen-containing basic compound, and the amount of 10% by mass or less is preferable in terms of sensitivity and developability of the non-exposed area.

  The positive resist composition of the present invention is dissolved in a solvent that dissolves each of the above components and coated on a support. Solvents used here 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-dimethyl Formamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, and the like are preferable. Or mixed to use.

  Among these, preferable solvents include propylene glycol monomethyl ether acetate, 2-heptanone, γ-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether And methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, N-methylpyrrolidone and tetrahydrofuran.

Such a positive resist composition of the present invention is applied onto a substrate to form a thin film. The film thickness of this coating film is preferably 0.2 to 1.2 μm.
Examples of the inorganic substrate that can be used in the present invention include a normal BareSi substrate, an SOG substrate, and a substrate having an inorganic antireflection film described below.
In the present invention, a commercially available inorganic or organic antireflection film can be used as necessary.

As the antireflection film, an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, α-silicon, and an organic film type made of a light absorber and a polymer material can be used. The former requires equipment such as a vacuum deposition apparatus, a CVD apparatus, and a sputtering apparatus for film formation. Examples of the organic antireflection film include a condensate of a diphenylamine derivative and a formaldehyde-modified melamine resin described in JP-B-7-69611, an alkali-soluble resin, a light absorber, and maleic anhydride copolymer described in US Pat. No. 5,294,680. A reaction product of a coalescence and a diamine type light absorbing agent, a resin binder described in JP-A-6-186863 and a methylolmelamine thermal crosslinking agent, a carboxylic acid group, an epoxy group and a light-absorbing group described in JP-A-6-118656. An acrylic resin-type antireflection film in the same molecule, a composition comprising methylol melamine and a benzophenone-based light absorber described in JP-A-8-87115, and a low-molecular light absorber added to a polyvinyl alcohol resin described in JP-A-8-179509 And the like.
Further, as the organic antireflection film, DUV30 series, DUV-40 series, ARC25, AC-2, AC-3, AR19, AR20, etc., manufactured by Brewer Science can be used.

Appropriate use of the resist solution on a substrate (eg, silicon / silicon dioxide coating) used for the manufacture of precision integrated circuit elements (on a substrate provided with the antireflection film if necessary), spinner, coater, etc. A good resist pattern can be obtained by applying through a predetermined coating method, exposing through a predetermined mask, baking and developing. Here, the exposure light is preferably light having a wavelength of 150 nm to 250 nm. Specific examples include a KrF excimer laser (248 nm), an ArF excimer laser (193 nm), an F ₂ excimer laser (157 nm), an X-ray, and an electron beam. The resist composition of the present invention is particularly preferably used for exposure with an ArF excimer laser.

Examples of the developer include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, diethylamine, and di-n. -Secondary amines such as butylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide. An alkaline aqueous solution (usually 0.1 to 10% by mass) of cyclic amines such as pyrrole and pihelidine can be used.
Furthermore, an appropriate amount of alcohol or surfactant may be added to the alkaline aqueous solution.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example.

Synthesis of Resin (1) 2-Ethyl-2-adamantyl methacrylate, isoadamantyl methacrylate, butyrolactone methacrylate and methacrylic acid were charged in a ratio of 25/25/40/10 and dissolved in methyl isobutyl ketone, and a solid content concentration of 30% 100 mL was prepared. To this solution, 4 mol% of a polymerization initiator V-601 manufactured by Wako Pure Chemical Industries, Ltd. was added dropwise to 10 mL of methyl isobutyl ketone heated to 80 ° C. over 4 hours in a nitrogen atmosphere. After completion of dropping, the reaction solution was heated and stirred for 4 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 1 L of a mixed solvent of distilled water / ISO propyl alcohol = 1/1, and the precipitated white powder was washed with 1 L of methanol to obtain the target resin (1). Was recovered.
The polymer composition ratio determined from C ¹³ NMR was 22/27/39/12. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 8700.
Resins having the composition ratio and molecular weight shown in the table below were synthesized in the same manner as in the above synthesis example. (Repeating units 1, 2, 3, 4 indicate the order from the left of the structural formula)

  The structures of the resins (1) to (18) are shown below.

Examples 1-42 and Comparative Examples 1-8
(Preparation and evaluation of positive resist composition)
The components shown in Table 2 below are dissolved in propylene glycol monomethyl ether acetate to prepare a solution having a solid content of 10% by mass, and this is filtered through a 0.1 μm polytetrafluoroethylene filter or polyethylene filter to obtain a positive resist solution. It was adjusted.

After applying ARC-29A manufactured by Brewer Science as a reflection preventing film on a silicon wafer at 78 nm using a spin coater, drying on a hot plate at 205 ° C. for 60 seconds, and then obtaining a positive resist composition obtained thereon. Apply and dry at 120 ° C. for 90 seconds to form a positive resist film of about 300 nm, and then a line pattern / space pattern with a pitch of 260 nm using an ArF excimer laser (ArF stepper manufactured by ISI with a wavelength of 193 nm and NA = 0.6) Using a mask having a one-to-one ratio, exposure was performed while changing the exposure amount. The heat treatment after the exposure was performed at 120 ° C. for 90 seconds, developed with a 2.38 mass% tetramethylammonium hydroxide aqueous solution, rinsed with distilled water, and a resist pattern was obtained by spin drying.
The resist pattern of the silicon wafer thus obtained was observed with a scanning microscope, and the obtained resist pattern was evaluated as follows. The results are shown in Table 2 and Table 3.

Line edge roughness: 50 points were measured at 5 μm in the longitudinal direction of a 130 nm line pattern (S-8840 manufactured by Hitachi), and 3σ was calculated. A smaller value indicates better performance.

Pattern collapse: When a mask having 15 lines in a one-to-one repetitive pattern with a line / space pattern ratio of 130 nm is used, and when the line pattern collapse is zero at the exposure amount for reproducing this mask size, it is less than 3 The case was evaluated as △, and the case more than that was evaluated as ×. A case where there is no pattern collapse indicates a good performance.

As surfactant,
W1: Mega Fuck F176 (Dainippon Ink Co., Ltd.) (Fluorine)
W2: Megafuck R08 (Dainippon Ink Co., Ltd.) (fluorine and silicone)
W3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.)
W4: Polyoxyethylene nonylphenyl ether W5: Troysol S-366 (manufactured by Troy Chemical Co., Ltd.)
Represents.

As basic compounds,
1 represents 1,5-diazabicyclo [4.3.0] -5-nonene (DBN);
2 represents bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebagate 3, tri-n-butylamine 4, triphenylimidazole 5, antipyrine 6 represents 2,6-diisopropylaniline .

  As the comparative resin R, 2-methyl-2-adamantyl methacrylate / mevalonic lactone methacrylate / t-butyl methacrylate (molar ratio 50/30/20) synthesized according to the example of JP-A-11-119434 is used. It was.

  As is apparent from the results of Tables 2 and 3, it can be seen that the positive resist composition of the present invention has excellent line edge roughness performance and excellent pattern collapse performance.

Claims (8)

(A) a resin whose solubility in an alkaline developer is increased by the action of an acid containing a repeating unit represented by the following general formula (Ia) and a repeating unit represented by the general formula (Ib); and (B) A positive resist composition comprising a compound represented by formula (I), (II) or (III).

In formulas (Ia) and (Ib), Ra ₁ independently represents a hydrogen atom or an alkyl group, and A represents a single bond .
In the formula (Ia), Ra ₁₁ represents an alkyl group having 1 to 4 carbon atoms, and Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with a carbon atom.
Wherein (Ib), Ra ₁₂ ~Ra ₁₄ each independently represent a hydrocarbon group, representing at least one alicyclic hydrocarbon group of Ra ₁₂ to Ra _14.

In general formulas (I) and (II),
R _{1 to} R ₃ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or an alkoxy group.
R ₄ and R ₅ may be the same or different and each represents a hydrogen atom, a cyano group, an alkyl group, an aryl group, or an alkoxy group.
Y ₁ and Y ₂ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom.
n represents an integer of 1 to 4. When n is 2 or more, a plurality of R ₁ and R ₂ may be the same or different.
Any two or more of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ may be bonded to form a ring structure.
In addition, at any position of R _{1 to} R ₃ , R ₄ , R ₅ , Y ₁ and Y ₂ , they are bonded via a linking group and have two or more structures of the general formula (I) or (II). You may do it.
X ⁻ represents a non-nucleophilic anion.

In general formula (III),
Ar represents an aryl group or an aromatic group containing a hetero atom.
R ₆ represents a hydrogen atom, a cyano group, an alkyl group or an aryl group.
R ₇ represents an alkyl group or an aryl group.
Y ₃ and Y ₄ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom. Y ₃ and Y ₄ may combine to form a ring.
Ar may combine with at least one of Y ₃ and Y ₄ to form a ring.
Ar and R ₆ may combine to form a ring.
Further, they may be bonded via a linking group at any position of Ar, R ₆ or R ₇ or at any position of Y ₃ or Y ₄ and have two or more structures of the general formula (III). .
X ⁻ represents a non-nucleophilic anion. (B) The positive resist composition according to claim 1, wherein the compound represented by the general formula (III) is a compound represented by the following general formula (IV ′ ).

In general formula (IV ′ ),
R _{8 to} R ₁₂ may be the same or different and each represents a hydrogen atom, a nitro group, a halogen atom, an alkyl group, an alkoxy group, an alkyloxycarbonyl group, an aryl group, or an acylamino group.
At least two of R _{8 to} R ₁₂ may be bonded to form a ring structure.
R ₁₃ represents a hydrogen atom, a cyano group, an alkyl group or an aryl group.
R ₁₄ represents an alkyl group or an aryl group.
Y ₅ and Y ₆ may be the same or different and each represents an alkyl group, an aryl group, an aralkyl group or an aromatic group containing a hetero atom.
Y ₅ and Y ₆ may combine to form a ring.
At least one of R _{8 to} R ₁₂ may be bonded to at least one of Y ₅ and Y ₆ to form a ring.
At least one of R _{8 to} R ₁₂ and R ₁₃ may combine to form a ring.
Further, at any position of R _{8 to} R ₁₄ or any position of Y ₅ or Y ₆ , they may be bonded via a linking group to have two or more structures of the general formula (IV ′ ).
X ⁻ represents a non-nucleophilic anion.   The positive resist composition according to claim 1, further comprising (C) a fluorine-based and / or silicon-based surfactant.   Furthermore, (D) the organic basic compound is contained, The positive resist composition as described in any one of Claims 1-3 characterized by the above-mentioned.   The positive resist composition according to claim 1, wherein the resin (A) further contains a repeating unit having a lactone structure represented by the following general formula (IV).

  In general formula (IV), R ₁ a 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 combination of two or more groups selected from the group consisting of ester groups.
  Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , Re ₁ Each independently represents 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.   The positive resist composition according to any one of claims 1 to 5, wherein the resin (A) further contains a repeating unit represented by the following general formula (AI).

  In general formula (AI), R _b0 Represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these. B ₂ Represents a group represented by any one of the following general formulas (V-1) to (V-4).

  In the general formulas (V-1) to (V-4), R _1b ~ R _5b Each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an alkenyl group which may have a substituent. R _1b ~ R _5b Two of these may combine to form a ring.   Resin (A) contains the repeating unit further represented by the following general formula (AII), The positive resist composition as described in any one of Claims 1-6 characterized by the above-mentioned.

  In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
  R ₂ c ~ R _Four c represents a hydrogen atom or a hydroxyl group each independently. However, R ₂ c ~ R _Four At least one of c represents a hydroxyl group. Pattern forming method forming a resist film from a resist composition according to any one of claims 1 to 7 exposing the resist film, characterized by development.