JP5358102B2 - Photosensitive composition, compound used for photosensitive composition, and pattern formation method using the photosensitive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition improved in PEB temperature dependency and exposure latitude and a pattern-forming method using the same, with respect to the photosensitive composition for use in the production process of a semiconductor such as IC, in the production of a circuit substrate of a liquid crystal, a thermal head and the like or in other photofabrication processes and a pattern-forming method using the same. <P>SOLUTION: The photosensitive composition comprises: (A) a compound capable of generating a bis(organosulfonyl)imidic acid of a specific structure upon irradiation with actinic ray or radiation; and (B) a resin that decomposes by the action of an acid to increase its solubility in an alkali developer. The pattern-forming method using the same is also provided. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a photosensitive composition used in a semiconductor manufacturing process such as IC, circuit boards such as liquid crystal and thermal head, and other photofabrication processes, a compound used in the photosensitive composition, and the photosensitive composition. The present invention relates to a pattern forming method using a conductive composition. More specifically, a photosensitive composition suitable for use as an exposure light source such as far ultraviolet rays of 250 nm or less, preferably 220 nm or less, and an irradiation source by an electron beam, the compound used in the photosensitive composition, and the photosensitive composition The present invention relates to a pattern forming method using an object.

  The chemically amplified photosensitive composition generates an acid in the exposed area by irradiation with radiation such as far ultraviolet light, and the acid-catalyzed reaction causes the solubility of the active radiation irradiated area and non-irradiated area in the developer. This is a pattern forming material for changing the pattern to form a pattern on the substrate.

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

On the other hand, when a further short wavelength light source, for example, an ArF excimer laser (193 nm) is used as the exposure light source, the compound having an aromatic group essentially shows a large absorption in the 193 nm region. It was not enough.
For this reason, an ArF excimer laser resist containing a resin having an alicyclic hydrocarbon structure has been developed. Various compounds have also been developed for photoacid generators that generate acid in exposed areas by irradiation with radiation such as far ultraviolet light. For example, compounds that generate bis (sulfonyl) imidic acid upon irradiation with far ultraviolet light or the like. A composition containing is disclosed. (JP 2003-261529, JP 2003-231673, JP 2002-268223, JP 2004-12554, JP 2004-62154, WO 05/040922 pamphlet) .
However, there are still many inadequacies and various improvements are desired. For example, it has been found that variations in temperature within the wafer surface during heating (PEB) using a hot plate after exposure affect the resulting pattern, and can be obtained within the wafer when a wafer having a large diameter is used. The pattern line width will be different. It is desired to improve such PEB temperature dependency.
Furthermore, it is difficult to achieve both improvement in PEB temperature dependency and expansion of exposure latitude, and it is desired to improve PEB temperature dependency and exposure latitude at the same time.

JP 2003-261529 A JP 2003-231673 A JP 2002-268223 A JP 2004-12554 A JP 2004-62154 A International Publication No. 05/040922 Pamphlet

Accordingly, an object of the present invention is to provide a photosensitive composition having improved PEB temperature dependency and exposure latitude, a compound used in the photosensitive composition, and a pattern forming method using the photosensitive composition. is there.

一般式（Ｉ）に於いて、
Ｒａは、フッ素原子で置換されたアルキル基又はフッ素原子若しくはフッ素原子を有する基で置換されたアリール基を表す。
Ｒｂは、α位がフッ素原子で置換されていないアルキル基であって、炭素数１〜３０の直鎖、分岐若しくは環状アルキル基あるいはこれらを組合せたアルキル基又はフッ素原子若しくはフッ素原子を有する基で置換されていないアリール基を表す。Ｒｂとしての、α位がフッ素原子で置換されていないアルキル基であって、炭素数１〜３０の直鎖、分岐若しくは環状アルキル基あるいはこれらを組合せたアルキル基は、置換基としてアルコキシ基、アルコキシカルボニル基、シアノ基又はオキソ基を有していても良い。
〔２〕
（Ａ）成分が、一般式（Ｉ）で表される酸のアニオンを有する、スルホニウム塩化合物又はヨードニウム塩化合物であることを特徴とする〔１〕に記載の感光性組成物。
〔３〕
（Ｂ）成分が、ヒドロキシスチレン繰り返し単位を有する樹脂であることを特徴とする〔１〕又は〔２〕に記載の感光性組成物。
〔４〕
（Ｂ）成分が、下記一般式（ＰＡ）で示される繰り返し単位を有する樹脂であることを特徴とする〔１〕〜〔３〕のいずれか１項に記載の感光性組成物。

一般式（ＰＡ）に於いて、
Ｒは、水素原子、ハロゲン原子又は１〜４個の炭素原子を有する直鎖もしくは分岐のアルキル基を表す。複数のＲは、各々同じでも異なっていてもよい。
Ａ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、アミド基、スルホンアミド基、ウレタン基、又はウレア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。
Ｒｐ_１は、下記式（ｐＩ）〜（ｐＶ）のいずれかの基を表す。

一般式（ｐＩ）〜（ｐＶ）中、
Ｒ₁₁は、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基又はｓｅｃ−ブチル基を表す。
Ｚは、炭素原子とともにシクロアルキル基を形成するのに必要な原子団を表す。
Ｒ₁₂〜Ｒ₁₆は、各々独立に、炭素数１〜４個の直鎖もしくは分岐のアルキル基、又は、シクロアルキル基を表す。
Ｒ₁₇〜Ｒ₂₁は、各々独立に、水素原子、炭素数１〜４個の直鎖もしくは分岐のアルキル基、又は、シクロアルキル基を表す。Ｒ₁₉、Ｒ₂₁のいずれかは炭素数１〜４個の直鎖もしくは分岐のアルキル基、又は、シクロアルキル基を表す。
Ｒ₂₂〜Ｒ₂₅は、各々独立に、水素原子、炭素数１〜４個の直鎖もしくは分岐のアルキル基、又は、シクロアルキル基を表す。Ｒ₂₃とＲ₂₄は、互いに結合して環を形成していてもよい。
〔５〕
（Ｂ）成分が、ラクトン構造を有する樹脂であることを特徴とする〔１〕〜〔４〕のいずれか１項に記載の感光性組成物。
〔６〕
〔１〕〜〔５〕のいずれか１項に記載の感光性組成物により形成された感光性膜。
〔７〕
〔６〕に記載の感光性膜を露光、現像する工程を含むことを特徴とするパターン形成方法。
本発明は上記の〔１〕〜〔７〕に関するものであるが、以下、その他の事項についても記載している。
（１） （Ａ）活性光線又は放射線の照射により下記一般式（Ｉ）で表される酸を発生する化合物及び
（Ｂ）酸の作用により分解し、アルカリ現像液への溶解性が増大する樹脂
を含有することを特徴とする感光性組成物。 [1]
(A) a compound that generates an acid represented by the following general formula (I) by irradiation with actinic rays or radiation, and (B) a resin that decomposes by the action of the acid and increases solubility in an alkali developer. The photosensitive composition characterized by the above-mentioned.

In general formula (I),
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb is an alkyl group in which the α-position is not substituted with a fluorine atom, and is a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, an alkyl group combining these, or a group having a fluorine atom or a fluorine atom. Represents an unsubstituted aryl group. Rb is an alkyl group that is not substituted with a fluorine atom at the α-position, and a linear, branched, or cyclic alkyl group having 1 to 30 carbon atoms or an alkyl group that is a combination of these is an alkoxy group, an alkoxy group as a substituent It may have a carbonyl group, a cyano group or an oxo group.
[2]
The photosensitive composition as described in [1], wherein the component (A) is a sulfonium salt compound or an iodonium salt compound having an anion of an acid represented by the general formula (I).
[3]
The photosensitive composition as described in [1] or [2], wherein the component (B) is a resin having a hydroxystyrene repeating unit.
[4]
(B) Component is resin which has a repeating unit shown by the following general formula (PA), The photosensitive composition of any one of [1]-[3] characterized by the above-mentioned.

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

In general formulas (pI) to (pV),
R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group.
Z represents an atomic group necessary for forming a cycloalkyl group together with a carbon atom.
R ₁₂ to R ₁₆ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms, or represents a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms , or a cycloalkyl group. Either a linear or branched alkyl group having 1 to 4 carbon atoms of R _19, R _21, or represents a cycloalkyl group.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms , or a cycloalkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.
[5]
(B) The photosensitive composition according to any one of [1] to [4], wherein the component is a resin having a lactone structure.
[6]
A photosensitive film formed of the photosensitive composition according to any one of [1] to [5] .
[7 ]
The pattern formation method characterized by including the process of exposing and developing the photosensitive film | membrane as described in [6].
The present invention relates to the above [1] to [ 7 ], but other matters are also described below.
(1) (A) a compound capable of generating an acid represented by the following general formula (I) by irradiation with actinic rays or radiation, and (B) a resin that decomposes by the action of the acid and increases solubility in an alkali developer. A photosensitive composition comprising:

In general formula (I),
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb represents an alkyl group that is not substituted with a fluorine atom at the α-position, or an aryl group that is not substituted with a fluorine atom or a group having a fluorine atom.

  (2) The photosensitive composition as described in (1), wherein the component (A) is a sulfonium salt compound or an iodonium salt compound having an anion of an acid represented by the general formula (I).

  (3) A compound that generates an acid represented by the following general formula (I) by irradiation with actinic rays or radiation.

In general formula (I),
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb represents an alkyl group that is not substituted with a fluorine atom at the α-position, or an aryl group that is not substituted with a fluorine atom or a group having a fluorine atom.

  (4) A compound represented by the following general formula (Ia):

In general formula (Ia):
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb represents an alkyl group that is not substituted with a fluorine atom at the α-position, or an aryl group that is not substituted with a fluorine atom or a group having a fluorine atom.

  (5) A pattern forming method comprising a step of forming a photosensitive film from the photosensitive composition according to (1) or (2), and exposing and developing the photosensitive film.

  The preferred embodiments of the present invention will be further described below.

  (6) The photosensitive composition as described in (1) or (2), wherein the resin as the component (B) is a resin having a hydroxystyrene-based repeating unit.

  (7) The photosensitive composition as described in (1) or (2), wherein the resin as the component (B) is a resin having a monocyclic or polycyclic alicyclic hydrocarbon structure.

  (8) The photosensitive composition as described in (1) or (2), wherein the resin as the component (B) is a resin having a lactone structure.

  (9) In the general formula (I), Ra is a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, a pentafluorophenyl group, and a 3,5-bis (trifluoromethyl) phenyl group. (1), (2) and the photosensitive composition in any one of (6)-(8) characterized by the above-mentioned.

  (10) Further, (A2) containing a compound capable of generating any acid selected from the following general formulas (AC1) to (AC3) upon irradiation with an actinic ray or radiation (1), (2 ) And (6) to (9).

In general formulas (AC1) to (AC3),
Rc ₁ represents an organic group.
Rc ₃ , Rc ₄ and Rc ₅ each independently represents a perfluoroalkyl group.
Rc ₃ and Rc ₄ may combine to form a ring.

  (11) The photosensitive composition according to any one of (1), (2) and (6) to (10), wherein the resin (B) has an acid-decomposable group having an acetal structure.

  The present invention can provide a photosensitive composition having improved PEB temperature dependency and exposure latitude, a compound used for the photosensitive composition, and a pattern forming method using the photosensitive composition.

Hereinafter, the best mode for carrying out the present invention will be described.
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 does not have a substituent and what has 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).

(A) Compound that generates acid represented by general formula (I) upon irradiation with actinic ray or radiation The photosensitive composition of the present invention is represented by the following general formula (I) upon irradiation with actinic ray or radiation. Contains compounds that generate acids.

In general formula (I),
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb represents an alkyl group that is not substituted with a fluorine atom at the α-position, or an aryl group that is not substituted with a fluorine atom or a group having a fluorine atom.

In the general formula (I), examples of the alkyl group in Ra include a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, or an alkyl group obtained by combining these.
The alkyl group in Ra is an alkyl group substituted with a fluorine atom, preferably a perfluoroalkyl group, more preferably a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, or a nonafluorobutyl group. It is.
The alkyl group of Ra may further have a substituent, and preferred substituents include halogen atoms other than fluorine atoms, alkoxy groups, alkoxycarbonyl groups, cyano groups, oxo groups and the like.
Examples of the aryl group in Ra include an aryl group having 6 to 14 carbon atoms, and a phenyl group is preferable.
The aryl group in Ra is an aryl group substituted with a fluorine atom or a group having a fluorine atom, and is preferably a pentafluorophenyl group or a 3,5-bis (trifluoromethyl) phenyl group.
The aryl group of Ra may further have a substituent. Preferred examples of the substituent include an alkyl group, a halogen atom other than a fluorine atom, an alkoxy group, an alkoxycarbonyl group, and a cyano group.
Examples of the alkyl group in which the α-position in Rb is not substituted with a fluorine atom include a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, or an alkyl group combining these.
The alkyl group of Rb may have a substituent, and preferred examples of the substituent include an alkoxy group, an alkoxycarbonyl group, a cyano group, and an oxo group.
Examples of the aryl group which is not substituted with a fluorine atom or a group having a fluorine atom in Rb include aryl groups having 6 to 14 carbon atoms, and preferably a phenyl group.
The aryl group of Rb may have a substituent, and preferred examples of the substituent include an alkyl group, an alkoxy group, an alkoxycarbonyl group, and a cyano group.

  Specific examples of the acid represented by formula (I) are shown below, but the present invention is not limited thereto.

  Among the compounds that generate an acid represented by general formula (I) upon irradiation with actinic rays or radiation, compounds represented by the following general formula (ZIa) or (ZIIa) can be exemplified.

In the general formula (ZIa),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
Xd ⁻ represents an anion of the acid represented by the general formula (I).

In the general formula (ZIa), two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring contains an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. May be. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (ZI-1a), (ZI-2a) and (ZI-3a) described later.

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

  More preferred (ZIa) components include compounds (ZI-1a), (ZI-2a), and (ZI-3a) described below.

Compound (ZI-1a) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZIa), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be an aryl group, and the rest may be an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.
The aryl group of the arylsulfonium compound is preferably an aryl group such as a phenyl group or a naphthyl group, or an aryl group having a heteroatom such as an indole residue or a pyrrole residue, more preferably a phenyl group or an indole residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.
The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.
Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are straight chain or straight chain alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, straight chain, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, and most preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

  The arylsulfonium cation is preferably a triphenylsulfonium cation which may be substituted, a naphthyltetrahydrothiophenium cation which may be substituted, or a phenyltetrahydrothiophenium cation which may be substituted.

Next, the compound (ZI-2a) will be described.
Compound (ZI-2a) is a compound in the case where R _{201 to} R ₂₀₃ in general formula (ZIa) each independently represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.
The aromatic ring-free organic group as R ₂₀₁ to R ₂₀₃ is generally 1 to 30 carbons, preferably 1 to 20 carbons.
R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear, branched, cyclic 2-oxoalkyl group, an alkoxycarbonylmethyl group, particularly A linear or branched 2-oxoalkyl group is preferred.

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

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

In the general formula (ZI-3a),
R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or a halogen atom.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
Rx and Ry each independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.
Any two or more of R _1c to R _7c, and R _x and R _y may be bonded to each other to form a ring structure, the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond May be included. Examples of the group formed by combining any two or more of R _{1c to} R _7c and R _x and R _y include a butylene group and a pentylene group.
Xd ⁻ represents an anion of the acid represented by the general formula (I).

The alkyl group as R _{1c to} R _7c may be either linear or branched, for example, an alkyl group having 1 to 20 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms. Examples thereof include a group (for example, methyl group, ethyl group, linear or branched propyl group, linear or branched butyl group, linear or branched pentyl group).
Preferable examples of the cycloalkyl group as R _{1c to} R _7c include a cycloalkyl group having 3 to 8 carbon atoms (for example, a cyclopentyl group and a cyclohexyl group).
The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).
Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably, the number of carbon atoms of R _{1c to} R _5c is The sum is 2-15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group as R _x and R _y include the same alkyl groups as R _{1c to} R _7c . The alkyl group as R _x and R _y is more preferably a linear or branched 2-oxoalkyl group or an alkoxycarbonyl group.
The cycloalkyl group as R _x and R _y may be the same as the cycloalkyl group as R _1c to R _7c. The cycloalkyl group as R _x and R _y is more preferably a cyclic 2-oxoalkyl group.
Examples of the linear, branched or cyclic 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .
Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _{1c to} R _5c .
R _x and R _y are preferably an alkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more.

In the general formula (ZIIa),
_R204 and _R205 each independently represents an aryl group, an alkyl group or a cycloalkyl group.

The aryl group of R ₂₀₄ and R _205, a phenyl group, a naphthyl group, more preferably a phenyl group.
The alkyl group as _R204 and _R205 may be either linear or branched, and is preferably a linear or branched alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, a propyl group). Butyl group, pentyl group).
The cycloalkyl group as R ₂₀₄ and R ₂₀₅ can preferably be mentioned a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl).
Examples of the substituent that R ₂₀₄ and R ₂₀₅ may have include, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 6 carbon atoms). 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.

  In the general formulas (ZIa) and (ZIIa), preferred cationic structures are shown below, but the present invention is not limited thereto.

  As a preferred specific example of the component (A), an arbitrary combination of the anion of the acid shown in the specific example of the acid represented by the general formula (I) and the cation can be mentioned.

  The component (A) is preferably a compound represented by the following general formula (Ia).

In general formula (Ia):
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb represents an alkyl group that is not substituted with a fluorine atom at the α-position, or an aryl group that is not substituted with a fluorine atom or a group having a fluorine atom.

  A typical compound represented by the general formula (Ia) can be synthesized, for example, by the method of the scheme shown below.

  That is, the sulfonamide represented by the general formula (C-1) and the sulfonic acid chloride represented by the general formula (C-2) are reacted in a solvent in the presence of a base to obtain a sulfone represented by the general formula (C-3). An imide is obtained. Here, the solvent is not particularly limited, but it is preferable to employ water. As the base, inorganic and organic bases can be appropriately employed, but inorganic bases are preferable. Specifically, alkali metal salts such as sodium hydroxide and potassium hydroxide can be mentioned as particularly preferred examples. The reaction temperature is from −20 ° C. to the boiling point of the solvent, and it is preferable to carry out the reaction preferably under ice cooling to 40 ° C. Subsequently, the target compound of the present invention represented by the general formula (Ia) is produced by salt exchange between the sulfonium bromide represented by the general formula (C-4) and the sulfonimide represented by the general formula (C-3). can do.

  The content of the component (A) in the composition is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and still more preferably 1 based on the total solid content of the photosensitive composition. It is -7 mass%, Most preferably, it is 3-7 mass%.

The photosensitive composition of this invention may contain the compound which generate | occur | produces an acid by irradiation of actinic light or a radiation other than the compound which generate | occur | produces the acid represented by general formula (I) by irradiation of actinic light or a radiation. Good.
Examples of such an acid generator include a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, a photochromic agent, or an actinic ray or radiation used for a microresist. A known compound that generates an acid by irradiation and a mixture thereof can be appropriately selected and used.

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

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

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

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation that may be used in combination (hereinafter also referred to as “combined acid generator”), the following general formulas (ZI), (ZII), (ZIII) The compound represented by these can be mentioned.

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

  Preferred organic anions include organic anions represented by the following general formulas (AN1) to (AN4).

In general formulas (AN1) and (AN2):
Rc ₁ represents an organic group.

Formula (AN1) and (AN2), as the organic group in Rc _1, include those having 1 to 30 carbon atoms, preferably may be substituted, an alkyl group, a cycloalkyl group, an aryl group, or a mixture, A group in which a plurality of them are linked by a linking group such as a single bond, —O—, —CO ₂ —, —S—, —SO ₃ —, —SO ₂ N (Rd ₁ ) — can be exemplified.
Rd ₁ represents a hydrogen atom or an alkyl group, and may form a ring structure with a bonded alkyl group, cycloalkyl group, or aryl group.
The organic group of rc _1, more preferably 1-position is a fluorine atom or an alkyl group substituted with a fluoroalkyl group, a phenyl group substituted with a fluorine atom or a fluoroalkyl group. By having a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by light irradiation is increased and the sensitivity is improved. When Rc ₁ has 5 or more carbon atoms, it is preferable that at least one carbon atom does not have all hydrogen atoms replaced by fluorine atoms, but leaves one part of the hydrogen atoms. More preferably, the number is larger than that of fluorine atoms. By not having a perfluoroalkyl group having 5 or more carbon atoms, ecotoxicity is reduced.
A particularly preferred embodiment of Rc ₁ is a group represented by the following general formula.

In the above general formula,
Rc ₆ is substituted with a perfluoroalkylene group having 4 or less carbon atoms, more preferably 2 to 4, more preferably 2 to 3, or 3 to 5 fluorine atoms and / or 1 to 3 fluoroalkyl groups. Represents a substituted phenylene group.
Ax represents a single bond or a divalent linking group (preferably —O—, —CO ₂ —, —S—, —SO ₃ —, —SO ₂ N (Rd ₁ ) —). Rd ₁ represents a hydrogen atom or an alkyl group, and may combine with Rc ₇ to form a ring structure.
Rc ₇ represents a hydrogen atom, a fluorine atom, a linear or branched alkyl group, a monocyclic or polycyclic cycloalkyl or an aryl group. The alkyl group, cycloalkyl group and aryl group preferably do not contain a fluorine atom as a substituent.

In the general formulas (AN3) and (AN4),
Rc ₃ , Rc ₄ and Rc ₅ each independently represents a perfluoroalkyl group.
Rc ₃ and Rc ₄ may combine to form a ring.

In general formulas (AN3) and (AN4), examples of the group formed by combining Rc ₃ and Rc ₄ include an alkylene group and an arylene group. Preferably, it is a C2-C4 perfluoroalkylene group. Rc ₃ and Rc ₄ are preferably bonded to form a ring, so that the acidity of the acid generated by light irradiation is increased and the sensitivity is improved, which is preferable.

In the general formula (ZI), the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
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).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (ZI-1), (ZI-2) and (ZI-3) described later.

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 (ZI) is, at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (ZI) It may be a compound.

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

Compound (ZI-1) is at least one R ₂₀₁ to R ₂₀₃ in formula (ZI) is an aryl group, an arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
In the arylsulfonium compound, all of R _{201 to} R ₂₀₃ may be an aryl group, or a part of R _{201 to} R ₂₀₃ may be an aryl group, and the rest may be an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.
The aryl group of the arylsulfonium compound is preferably an aryl group such as a phenyl group or a naphthyl group, or an aryl group having a hetero atom such as an indole residue or a pyrrole residue, more preferably a phenyl group or an indole residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.
The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.
The aryl group, alkyl group, and cycloalkyl group of R _{201 to} R ₂₀₃ are an alkyl group (for example, having 1 to 15 carbon atoms), a cycloalkyl group (for example, having 3 to 15 carbon atoms), an aryl group (for example, having 6 to 14 carbon atoms). ), An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group as a substituent. Preferred substituents are straight chain, branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, straight chain, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, and more preferably They are a C1-C4 alkyl group and a C1-C4 alkoxy group. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (ZI-2) will be described.
Compound (ZI-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.
The aromatic ring-free organic group as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
The aromatic ring-free organic group as R ₂₀₁ to R ₂₀₃ is preferably an alkyl group, a cycloalkyl group, an allyl group, a vinyl group, more preferably a linear, branched or cyclic 2-oxoalkyl group, An alkoxycarbonylmethyl group, still more preferably a linear, branched 2-oxoalkyl group.

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

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

In general formula (ZI-3),
R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group or a halogen atom.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
Rx and Ry each independently represents an alkyl group, a cycloalkyl group, an allyl group or a vinyl group.
Any two or more of R _1c to R _7c, and R _x and R _y may be bonded to each other to form a ring structure, the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond May be included. Examples of the group formed by combining any two or more of R _{1c to} R _7c and R _x and R _y include a butylene group and a pentylene group.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ^{− in} formula (ZI).

The alkyl group as R _{1c to} R _7c may be either linear or branched, for example, an alkyl group having 1 to 20 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms. Examples thereof include a group (for example, methyl group, ethyl group, linear or branched propyl group, linear or branched butyl group, linear or branched pentyl group).
Examples of the cycloalkyl group as R _{1c to} R _7c include a cycloalkyl group having 3 to 8 carbon atoms (for example, a cyclopentyl group and a cyclohexyl group).
The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).
Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _1c to R _5c is 2 ~ 15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group as R _x and R _y include the same alkyl groups as R _{1c to} R _7c . The alkyl group as R _x and R _y is more preferably a linear or branched 2-oxoalkyl group or an alkoxycarbonylmethyl group.
The cycloalkyl group as R _x and R _y may be the same as the cycloalkyl group as R _1c to R _7c. The cycloalkyl group as R _x and R _y is more preferably a cyclic 2-oxoalkyl group.
Examples of the linear, branched or cyclic 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .
Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _{1c to} R _5c .
R _x and R _y are preferably an alkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more.

In the general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group or a cycloalkyl group.
X ⁻ represents a non-nucleophilic anion and is the same as the non-nucleophilic anion of X ^{− in} formula (ZI).

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 either straight-chain, branched, preferably a straight-chain or branched alkyl group (e.g., methyl group, an ethyl group having 1 to 10 carbon atoms, a propyl group Butyl group, pentyl group).
The cycloalkyl group as R ₂₀₄ to R ₂₀₇ is preferably, and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl).
The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (e.g., 6 carbon atoms 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.

  Among the compounds that generate an acid upon irradiation with actinic rays or radiation that may be used in combination, compounds represented by the following general formulas (ZIV), (ZV), and (ZVI) can be exemplified. .

In the general formulas (ZIV) to (ZVI),
Ar ₃ and Ar ₄ each independently represents an aryl group.
R ₂₀₈ represents an alkyl group, a cycloalkyl group, or an aryl group.
R ₂₀₉ and R ₂₁₀ each independently represents an alkyl group, a cycloalkyl group, an aryl group, or an electron-withdrawing group. R ₂₀₉ is preferably an aryl group. R ₂₁₀ is preferably an electron-withdrawing group, more preferably a cyano group or a fluoroalkyl group.
A represents an alkylene group, an alkenylene group or an arylene group.

Among the compounds that generate an acid upon irradiation with actinic rays or radiation, more preferred are compounds represented by the general formulas (ZI) to (ZIII), and still more preferred are compounds represented by (ZI). Particularly preferred are compounds represented by (ZI-1) to (ZI-3).
Furthermore, the compound which generate | occur | produces the acid represented by the following general formula (AC1)-(AC3) by irradiation of actinic light or a radiation is preferable.

In general formulas (AC1) to (AC3),
Rc ₁ represents an organic group.
Rc ₃ , Rc ₄ and Rc ₅ each independently represents a perfluoroalkyl group.
Rc ₃ and Rc ₄ may combine to form a ring.

That is, particularly preferred combined acid generators include compounds in which, in the structure of the general formula (ZI), X ⁻ is an anion of an acid selected from the general formulas (AN1), (AN2), and (AN3). Can do.

  Examples of particularly preferred acid generators used in combination are listed below, but the present invention is not limited thereto.

The combined acid generator can be used alone or in combination of two or more. When two or more types are used in combination, it is preferable to combine two types of compounds that generate two types of organic acids that differ in the total number of atoms excluding hydrogen atoms by two or more.
The content of the combined acid generator in the composition is preferably from 0.1 to 20% by mass, more preferably from 0.5 to 10% by mass, and even more preferably from 1 to 20% by mass, based on the total solid content of the photosensitive composition. It is 7 mass%, Most preferably, it is 1-4 mass%.

  The content of the component (A) and the combined acid generator in the total composition is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, based on the total solid content of the photosensitive composition. %, More preferably 1 to 7% by mass, and particularly preferably 3 to 7% by mass.

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

A group preferable as a group that can be decomposed by an acid is a group in which a hydrogen atom of a —COOH group or —OH group is substituted with a group capable of leaving with an acid.
Examples of the group leaving with an acid include -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), -C (R ₀₁ ) (R ₀₂ ). ) (OR ₃₉ ) and the like.
In the formula, R _{36 to} R ₃₉ each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be bonded to each other to form a ring.
R _{01 and} R ₀₂ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.
In the present invention, the acid-decomposable group is preferably an acetal group or a tertiary ester group.

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

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

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

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

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

When the photosensitive composition of the present invention is irradiated with KrF excimer laser light, electron beam, X-ray, or high energy light (preferably EUV) having a wavelength of 50 nm or less, the resin of component (B) is a hydroxystyrene repeating unit. It is preferable to have. More preferably, a copolymer having a hydroxystyrene repeating unit / hydroxystyrene repeating unit protected with an acid-decomposable group, a copolymer having a hydroxystyrene repeating unit / (meth) acrylate repeating unit protected with an acid-decomposing group Is preferred.
Although the specific example of resin of (B) component used for this invention is shown below, this invention is not limited to these.

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

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

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

  Resin that has a monocyclic or polycyclic alicyclic hydrocarbon structure, decomposes by the action of an acid, and increases solubility in an alkali developer (hereinafter also referred to as “alicyclic hydrocarbon-based acid-decomposable resin”) Is selected from the group consisting of repeating units having a partial structure containing an alicyclic hydrocarbon represented by the following general formula (pI) to general formula (pV) and repeating units represented by the following general formula (II-AB). It is preferable that the resin has at least one kind.

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

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

  The general formula (II-AB) is more preferably the following general formula (II-AB1) or general formula (II-AB2).

In general formulas (II-AB1) and (II-AB2),
R ₁₃ ′ to R ₁₆ ′ each independently represents a hydrogen atom, a halogen atom, a cyano group, —COOH, —COOR ₅ , a group that decomposes by the action of an acid, —C (═O) —XA′—R. ₁₇ ′ represents an alkyl group or a cycloalkyl group. At least two of R ₁₃ ′ to R ₁₆ ′ may combine to form a ring.
Here, R ₅ represents an alkyl group, a cycloalkyl group, or a group having a lactone structure.
X represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.
A ′ represents a single bond or a divalent linking group.
R ₁₇ ′ represents —COOH, —COOR ₅ , —CN, a hydroxyl group, an alkoxy group, —CO—NH—R ₆ , —CO—NH—SO ₂ —R ₆ or a group having a lactone structure.
R ₆ represents an alkyl group or a cycloalkyl group.
n represents 0 or 1.

In the general formulas (pI) to (pV), the alkyl group in R _{12 to} R ₂₅ represents a linear or branched alkyl group having 1 to 4 carbon atoms, for example, a methyl group, an ethyl group, or the like. Can be mentioned.

The cycloalkyl group represented by R _{12 to} R ₂₅ or the cycloalkyl group formed by Z and the carbon atom may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These cycloalkyl groups may have a substituent.

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

  As further substituents of these alkyl groups and cycloalkyl groups, alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, alkoxycarbonyl groups (carbon numbers) 2-6). Examples of the substituent that the alkyl group, alkoxy group, alkoxycarbonyl group and the like may further have include a hydroxyl group, a halogen atom, and an alkoxy group.

The structures represented by the general formulas (pI) to (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 structure in which a hydrogen atom of a carboxylic acid group, a sulfonic acid group, a phenol group, or a thiol group is substituted with a structure represented by the general formulas (pI) to (PV), preferably a carboxylic acid Group, the hydrogen atom of a sulfonic acid group is the structure substituted by the structure represented by general formula (pI)-(PV).

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

In the general formula (PA),
R represents a hydrogen atom, a halogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups. Represents. A single bond and —COO—CH ₂ — are preferable.
Rp ₁ represents any group of the above formulas (pI) to (pV).

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

  Hereinafter, although the specific example of the repeating unit shown by general formula (PA) is shown, this invention is not limited to this.

In specific examples, Rx represents H, CH ₃ , CF ₃ , and CH ₂ OH, and Rxa and Rxb each represents an alkyl group having 1 to 4 carbon atoms.

Examples of the halogen atom in the general formula (II-AB), R ₁₁ ′, and R ₁₂ ′ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

Examples of the alkyl group for R ₁₁ ′ and R ₁₂ ′ include linear or branched alkyl groups having 1 to 10 carbon atoms.

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

Examples of the skeleton of the alicyclic hydrocarbon formed include the same alicyclic hydrocarbon groups as R _{12 to} R _{25 in} the general formulas (pI) to (pV).

The alicyclic hydrocarbon skeleton may have a substituent. Examples of such a substituent include R ₁₃ ′ to R ₁₆ ′ in the general formula (II-AB1) or (II-AB2).

In the alicyclic hydrocarbon-based acid-decomposable resin according to the present invention, the group decomposed by the action of an acid has a partial structure containing the alicyclic hydrocarbon represented by the general formula (pI) to the general formula (pV). It can be contained in at least one kind of repeating unit among the repeating unit having, the repeating unit represented by formula (II-AB), and the repeating unit of the copolymerization component described later.
One acid-decomposable repeating unit may be used, but it is preferable to use two or more acid-decomposable repeating units having different numbers of carbon atoms in the acid leaving group. Thereby, the balance between the resolution and the exposure latitude is improved.

Various substituents of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-AB1) or the general formula (II-AB2) are atomic groups for forming an alicyclic structure in the general formula (II-AB). It can also be a substituent of the atomic group Z ′ for forming a bridged alicyclic structure.

  Specific examples of the repeating unit represented by the general formula (II-AB1) or (II-AB2) include the following specific examples, but the present invention is not limited to these specific examples.

The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a lactone group. As the lactone group, any group can be used as long as it has a lactone structure, but a group having a 5- to 7-membered ring lactone structure is preferred, and a polycyclic structure is added to the 5- to 7-membered ring lactone structure. Those in which other ring structures are condensed to form a spiro structure are preferred. It is more preferable to have a repeating unit having a group having a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-16). Further, a group having a lactone structure may be directly bonded to the main chain. Preferred lactone structures are (LC1-1), (LC1-4), (L
C1-5), (LC1-6), (LC1-13), and (LC1-14). By using a specific lactone structure, line edge roughness and development defects are improved.

The lactone structure moiety may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. When n2 is 2 or more, a plurality of substituents (Rb ₂ ) may be the same or different, and a plurality of substituents (Rb ₂ ) may be bonded to form a ring.

As the repeating unit having a group having a lactone structure represented by any of the general formulas (LC1-1) to (LC1-16), R _{13 in the} general formula (II-AB1) or (II-AB2) may be used. Wherein at least one of 'to R ₁₆ ' has a group represented by general formula (LC1-1) to (LC1-16) (for example, R _{5 of} -COOR ₅ is represented by general formula (LC1-1) to ( And a repeating unit represented by the following general formula (AI).

In general formula (AI),
Rb ₀ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. Preferred substituents that the alkyl group represented by Rb ₀ may have include a hydroxyl group and a halogen atom.
Examples of the halogen atom for Rb ₀ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Rb ₀ is preferably a hydrogen atom or a methyl group.
Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent group obtained by combining these. Preferably a single bond, -Ab ₁ -CO ₂ - is a linking group represented by. Ab ₁ is a linear, branched alkylene group, monocyclic or polycyclic cycloalkylene group, preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group or a norbornylene group.
V represents a group represented by any one of the general formulas (LC1-1) to (LC1-16).

The repeating unit having a lactone structure usually has an optical isomer, but any optical isomer may be used. One optical isomer may be used alone, or a plurality of optical isomers may be mixed and used. When one kind of optical isomer is mainly used, the optical purity (ee) thereof is preferably 90 or more, more preferably 95 or more.
The content of the repeating unit having a lactone structure is preferably from 15 to 60 mol%, more preferably from 20 to 50 mol%, still more preferably from 30 to 50 mol%, based on all repeating units in the polymer.

  Particularly preferred repeating units having a lactone group include the following repeating units. By selecting the optimum lactone structure, the pattern profile and the density dependence become good.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a repeating unit having an alicyclic hydrocarbon structure substituted with a polar group. This improves the substrate adhesion and developer compatibility. The alicyclic hydrocarbon structure of the alicyclic hydrocarbon structure substituted with a polar group is preferably an adamantyl group, a diamantyl group, or a norbornane group. The polar group is preferably a hydroxyl group or a cyano group. As the alicyclic hydrocarbon structure substituted with a preferable polar group, partial structures represented by the following general formulas (VIIa) to (VIId) are preferable.

In general formulas (VIIa) to (VIIc),
R _{2c to} R _4c each independently represents a hydrogen atom, a hydroxyl group or a cyano group. However, at least one of R _{2c to} R _4c represents a hydroxyl group or a cyano group. Preferably, one or two of R _{2c to} R _4c are a hydroxyl group and the rest are hydrogen atoms. In general formula (VIIa), it is more preferable that two of R _{2c to} R _4c are a hydroxyl group and the remaining is a hydrogen atom.

As the repeating unit having a group represented by the general formulas (VIIa) to (VIId), at least one of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-AB1) or (II-AB2) is the above. Those having groups represented by the general formulas (VIIa) to (VIId) (for example, —COOR ₅₎
R ₅ in the formula represents a group represented by general formulas (VIIa) to (VIId)), or the following general formula (A
Examples include the repeating units represented by IIa) to (AIId).

In general formulas (AIIa) to (AIId),
R _1c represents a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group.
R _{2c to} R _4c are in the general formulas (VIIa) to (VIIc). Have the same meanings as R _2c ~R _4c.

  The content of the repeating unit having an alicyclic hydrocarbon structure substituted with a polar group is preferably 5 to 40 mol%, more preferably 5 to 30 mol%, still more preferably 10 to 25 mol based on all repeating units in the polymer. %.

  Specific examples of the repeating unit represented by the general formulas (AIIa) to (AIId) are given below, but the present invention is not limited thereto.

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

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

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

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention preferably has a repeating unit having an alkali-soluble group. As an alkali-soluble group, a carboxyl group, a sulfonamide group, a sulfonylimide group, a bisulsulfonylimide group, an aliphatic alcohol substituted with an electron-attracting group at the α-position (preferably a structure represented by the following general formula (F1)) It is more preferable to have a repeating unit having a carboxyl group.

In general formula (F1),
R _{50 to} R ₅₅ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _{50 to} R ₅₅ represents a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and all of R _{50 to} R ₅₅ are preferably fluorine atoms. .

  By having a repeating unit having an alkali-soluble group, the resolution in contact hole applications is increased. The repeating unit having an alkali-soluble group includes a repeating unit in which an alkali-soluble group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or an alkali in the main chain of the resin through a linking group. Either a repeating unit to which a soluble group is bonded, or a polymerization initiator or chain transfer agent having an alkali-soluble group is used at the time of polymerization and introduced at the end of the polymer chain, and the linking group is monocyclic or polycyclic. It may have a cyclic hydrocarbon structure. Particularly preferred are repeating units of acrylic acid or methacrylic acid.

  As for content of the repeating unit which has an alkali-soluble group, 1-20 mol% is preferable with respect to all the repeating units in a polymer, More preferably, it is 3-15 mol%, More preferably, it is 5-10 mol%.

  Specific examples of the repeating unit having an alkali-soluble group are shown below, but the present invention is not limited thereto.

  The alicyclic hydrocarbon-based acid-decomposable resin of the present invention may further have a repeating unit that has an alicyclic hydrocarbon structure and does not exhibit acid decomposability. This can reduce the elution of low molecular components from the resist film to the immersion liquid during immersion exposure. Examples of such a repeating unit include 1-adamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and cyclohexyl (meth) acrylate.

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

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

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

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit having an acid-decomposable group is preferably 10 to 60 mol%, more preferably 20 to 50 mol%, still more preferably 25 in all repeating structural units. -40 mol%.

  In the alicyclic hydrocarbon-based acid-decomposable resin, the content of the repeating unit having a partial structure containing the alicyclic hydrocarbon represented by the general formulas (pI) to (pV) is 20 to 70 in all the repeating structural units. The mol% is preferable, more preferably 20 to 50 mol%, still more preferably 25 to 40 mol%.

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

When the composition of the present invention is for ArF exposure, the resin preferably has no aromatic group from the viewpoint of transparency to ArF light.
The alicyclic hydrocarbon-based acid-decomposable resin used in the present invention is preferably one in which all of the repeating units are composed of (meth) acrylate-based repeating units. In this case, all of the repeating units may be methacrylate repeating units, all of the repeating units may be acrylate repeating units, or a mixture of methacrylate repeating units / acrylate repeating units, but all of the acrylate repeating units may be used. It is preferable that it is 50 mol% or less of a repeating unit. More preferably 20 to 50 mol% of repeating units having a partial structure containing an alicyclic hydrocarbon represented by general formulas (pI) to (pV), 20 to 50 mol% of repeating units having a lactone structure, It is a copolymer having 5 to 30 mol% of repeating units having a substituted alicyclic hydrocarbon structure, or a copolymer containing 0 to 20 mol% of other repeating units.

Particularly preferable resins include 20 to 50 mol% of repeating units having an acid-decomposable group represented by the following general formulas (ARA-1) to (ARA-5), and general formulas (ARL-1) to (ARL-6). ) Having a lactone group represented by general formulas (ARH-1) to (ARH-3) and having a alicyclic hydrocarbon structure substituted with a polar group represented by general formulas (ARH-1) to (ARH-3) 5 The resin having ˜30 mol%, or further the repeating unit having a structure represented by the carboxyl group or the general formula (F1) or the alicyclic hydrocarbon structure and not having acid decomposability, 5 to 20 It is a resin containing mol%.
In the formula, Rxy ₁ represents a hydrogen atom or a methyl group, and Rxa ₁ and Rxb ₁ each independently represents a methyl group or an ethyl group.

The alicyclic hydrocarbon-based acid-decomposable resin used in the present invention can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and the polymerization is performed by heating, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable. Examples of the reaction solvent include ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate, amide solvents such as dimethylformamide and dimethylacetamide, Furthermore, the solvent which melt | dissolves the composition of this invention like the below-mentioned propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone is mentioned. More preferably, the polymerization is performed using the same solvent as that used in the resist composition of the present invention. Thereby, generation | occurrence | production of the particle at the time of a preservation | save can be suppressed.
The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon. As a polymerization initiator, a commercially available radical initiator (azo initiator, peroxide, etc.) is used to initiate the polymerization. As the radical initiator, an azo initiator is preferable, and an azo initiator having an ester group, a cyano group, or a carboxyl group is preferable. Preferred examples of the initiator include azobisisobutyronitrile, azobisdimethylvaleronitrile, dimethyl 2,2′-azobis (2-methylpropionate) and the like. A chain transfer agent such as a thiol compound may be used in combination with the polymerization initiator. 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 5 to 50% by mass, preferably 10 to 30% by mass. The reaction temperature is usually 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 60-100 ° C.

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

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

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

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

The weight average molecular weight of the resin as the component (B) is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, and particularly preferably 5,000 to as a polystyrene converted value by the GPC method. 15,000. The weight average molecular weight is 1,000-2.
By setting the value to 00,000, it is possible to prevent deterioration of heat resistance and dry etching resistance, and it is possible to prevent developability and deterioration of film forming property due to increase in viscosity.
The molecular weight distribution is usually 1 to 5, preferably 1 to 2, more preferably 1.3 to 2. The smaller the molecular weight distribution, the better the resolution and the resist shape, and the smoother the side wall of the resist pattern, the better the roughness.

In the photosensitive composition of the present invention, the blending amount of the resin of the component (B) in the entire composition is preferably 60 to 99% by mass, more preferably 80 to 98% by mass in the total solid content.
In the present invention, the resins may be used alone or in combination.

The dissolution control compound having a molecular weight of 3000 or less having at least one selected from an alkali-soluble group, a hydrophilic group, and an acid-decomposable group. The photosensitive composition of the present invention is selected from an alkali-soluble group, a hydrophilic group, and an acid-decomposable group. It may contain at least one dissolution control compound having a molecular weight of 3000 or less (hereinafter also referred to as “dissolution inhibitor compound”).
Examples of the dissolution control compound include a carboxyl group, a sulfonylimide group, a compound having an alkali-soluble group such as a hydroxyl group substituted at the α-position with a fluoroalkyl group, a hydroxyl group, a lactone group, a cyano group, an amide group, a pyrrolidone group, a sulfone group. A compound having a hydrophilic group such as an amide group or a compound containing a group capable of decomposing by the action of an acid to release an alkali-soluble group or a hydrophilic group is preferable. The group capable of decomposing by the action of an acid to release an alkali-soluble group or a hydrophilic group is preferably a group in which a carboxyl group or a hydroxyl group is protected with an acid-eliminable group. In order not to lower the permeability of 220 nm or less as the dissolution control compound, it is preferable to use a compound that does not contain an aromatic ring, or to use a compound having an aromatic ring in an amount of 20 wt% or less based on the solid content of the composition.
Preferred dissolution control compounds include carboxylic acid compounds having an alicyclic hydrocarbon structure such as adamantane (di) carboxylic acid, norbornane carboxylic acid, and cholic acid, or compounds obtained by protecting the carboxylic acid with an acid leaving group, saccharides, etc. A polyol having a hydroxyl group protected with an acid-decomposable group is preferred.

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

  The addition amount of the dissolution control compound is preferably 3 to 40% by mass, more preferably 5 to 20% by mass, based on the solid content of the photosensitive composition.

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

Basic Compound The photosensitive composition of the present invention preferably contains a basic compound in order to reduce the change in performance over time from exposure to heating or to control the diffusibility of the acid generated by exposure in the film. .

  Examples of basic compounds include nitrogen-containing basic compounds and onium salt compounds. Preferable nitrogen-containing basic compound structures include compounds having partial structures represented by the following general formulas (A) to (E).

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

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

  Preferable compounds include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, and piperidine, and may have a substituent. More preferable compounds include compounds having an imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, trialkylamine structure, aniline structure or pyridine structure, alkylamine derivatives having a hydroxyl group and / or an ether bond, hydroxyl groups and / or Or the aniline derivative which has an ether bond etc. can be mentioned.

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

  Preferred examples of the basic compound further include an amine compound having a phenoxy group and an ammonium salt compound having a phenoxy group.

As the amine compound, a primary, secondary or tertiary amine compound can be used, and an amine compound in which at least one alkyl group is bonded to a nitrogen atom is preferable. The amine compound is more preferably a tertiary amine compound. As long as at least one alkyl group (preferably having 1 to 20 carbon atoms) is bonded to a nitrogen atom, the amine compound has an cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group (preferably having 3 to 20 carbon atoms). Preferably C6-C12) may be bonded to a nitrogen atom.
The amine compound preferably has an oxygen atom in the alkyl chain and an oxyalkylene group is formed. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group.

As the ammonium salt compound, a primary, secondary, tertiary, or quaternary ammonium salt compound can be used, and an ammonium salt compound in which at least one alkyl group is bonded to a nitrogen atom is preferable. As long as at least one alkyl group (preferably having 1 to 20 carbon atoms) is bonded to a nitrogen atom, the ammonium salt compound has a cycloalkyl group (preferably having 3 to 20 carbon atoms) or an aryl group in addition to the alkyl group. (Preferably having 6 to 12 carbon atoms) may be bonded to a nitrogen atom.
The ammonium salt compound preferably has an oxygen atom in the alkyl chain and an oxyalkylene group is formed. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group.
Examples of the anion of the ammonium salt compound include halogen atoms, sulfonates, borates, and phosphates. Among them, halogen atoms and sulfonates are preferable. As the halogen atom, chloride, bromide, and iodide are particularly preferable. As the sulfonate, an organic sulfonate having 1 to 20 carbon atoms is particularly preferable. Examples of the organic sulfonate include alkyl sulfonates having 1 to 20 carbon atoms and aryl sulfonates. The alkyl group of the alkyl sulfonate may have a substituent, and examples of the substituent include fluorine, chlorine, bromine, alkoxy groups, acyl groups, and aryl groups. Specific examples of the alkyl sulfonate include methane sulfonate, ethane sulfonate, butane sulfonate, hexane sulfonate, octane sulfonate, benzyl sulfonate, trifluoromethane sulfonate, pentafluoroethane sulfonate, and nonafluorobutane sulfonate. Examples of the aryl group of the aryl sulfonate include a benzene ring, a naphthalene ring, and an anthracene ring. The benzene ring, naphthalene ring and anthracene ring may have a substituent, and the substituent is preferably a linear or branched alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms. Specific examples of the linear or branched alkyl group and cycloalkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, i-butyl, t-butyl, n-hexyl, cyclohexyl and the like. Examples of the other substituent include an alkoxy group having 1 to 6 carbon atoms, a halogen atom, cyano, nitro, an acyl group, and an acyloxy group.

  The amine compound having a phenoxy group and the ammonium salt compound having a phenoxy group are those having a phenoxy group at the terminal opposite to the nitrogen atom of the alkyl group of the amine compound or ammonium salt compound. The phenoxy group may have a substituent. Examples of the substituent of the phenoxy group include an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a carboxyl group, a carboxylic acid ester group, a sulfonic acid ester group, an aryl group, an aralkyl group, an acyloxy group, and an aryloxy group. Etc. The substitution position of the substituent may be any of the 2-6 positions. The number of substituents may be any in the range of 1 to 5.

It is preferable to have at least one oxyalkylene group between the phenoxy group and the nitrogen atom. The number of oxyalkylene groups is one or more in the molecule, preferably 3 to 9, and more preferably 4 to 6. Among the oxyalkylene groups, an oxyethylene group (—CH ₂ CH ₂ O—) or an oxypropylene group (—CH (CH ₃ ) CH ₂ O— or —CH ₂ CH ₂ CH ₂ O—) is preferable, and more preferably oxy Ethylene group.

  The amine compound having a phenoxy group is prepared by reacting a primary or secondary amine having a phenoxy group with a haloalkyl ether by heating, and then adding an aqueous solution of a strong base such as sodium hydroxide, potassium hydroxide or tetraalkylammonium. It can be obtained by extraction with an organic solvent such as ethyl acetate or chloroform. Alternatively, after reacting by heating a primary or secondary amine and a haloalkyl ether having a phenoxy group at the end, an aqueous solution of a strong base such as sodium hydroxide, potassium hydroxide, or tetraalkylammonium is added, and then ethyl acetate, It can be obtained by extraction with an organic solvent such as chloroform.

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

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

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

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

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

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

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

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

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

Surface Hydrophobic Resin When the photosensitive film made of the photosensitive composition of the present invention is exposed through immersion water, a surface hydrophobizing resin can be further added as necessary. Thereby, the receding contact angle on the surface of the photosensitive film can be improved, and the immersion water followability can be improved. As the surface hydrophobizing resin, any resin can be used as long as the receding contact angle of the surface can be improved by addition, but a resin having at least one of fluorine atom and silicon atom is preferable. The addition amount can be adjusted as appropriate so that the receding contact angle of the photosensitive film is 60 ° to 80 °.
1 to 5% by mass.
The receding contact angle is the contact angle measured when the contact line at the droplet-substrate interface recedes, and is useful for simulating the ease of droplet movement under dynamic conditions. It is generally known. In simple terms, it can be defined as the contact angle when the droplet interface recedes when the droplet discharged from the needle tip is deposited on the substrate and then sucked into the needle again. It can be measured by using a contact angle measuring method generally called an expansion / contraction method.
In the immersion exposure process, the immersion head needs to move on the wafer following the movement of the exposure head to scan the wafer at high speed to form the exposure pattern. In this case, the contact angle of the immersion liquid with respect to the resist film is important, and the resist is required to follow the high-speed scanning of the exposure head without remaining droplets.

Organic Solvent The photosensitive composition of the present invention is used by dissolving the above components in a predetermined organic solvent.
Examples of the organic solvent that can be used include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl. Ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N -Dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, etc.

In the present invention, the organic solvent may be used alone or in combination, but it is preferable to use a mixed solvent containing two or more solvents having different functional groups. As a result, the solubility of the material is increased, and not only the generation of particles over time can be suppressed, but also a good pattern profile can be obtained. The mixed solvent containing two or more solvents having different functional groups is at least selected from a solvent containing a hydroxyl group, a solvent having an ester structure, a solvent having a ketone structure, a solvent having a lactone structure, and a solvent having a carbonate structure. A mixed solvent containing two kinds is preferred.
As the mixed solvent having different functional groups, the following mixed solvents (S1) to (S6) are preferable.
(S1) a mixed solvent containing at least a solvent containing a hydroxyl group and a solvent not containing a hydroxyl group,
(S2) a mixed solvent containing at least a solvent having an ester structure and a solvent having a ketone structure;
(S3) a mixed solvent containing at least a solvent having an ester structure and a solvent having a lactone structure;
(S4) a mixed solvent containing at least a solvent having an ester structure, a solvent having a lactone structure, and a solvent having a hydroxyl group;
(S5) a mixed solvent containing at least a solvent having an ester structure, a solvent having a carbonate structure, and a solvent having a hydroxyl group;
(S6) A mixed solvent containing at least a solvent having an ester structure, a solvent having a ketone structure, and a solvent having a lactone structure.
As a result, the generation of particles during storage of the resist solution can be reduced, and the generation of defects during application can be suppressed.

Examples of the solvent containing a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Particularly preferred are propylene glycol monomethyl ether and ethyl lactate.
Examples of the solvent not containing a hydroxyl group include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, and butyl acetate are preferable, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2-heptanone and cyclohexanone are particularly preferred.
Examples of the solvent having a ketone structure include cyclohexanone and 2-heptanone, and 2-heptanone is preferable.
Examples of the solvent having an ester structure include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, and butyl acetate, and propylene glycol monomethyl ether acetate is preferable.
Examples of the solvent having a lactone structure include γ-butyrolactone.
Examples of the solvent having a carbonate structure include propylene carbonate and ethylene carbonate, with propylene carbonate being preferred.

The mixing ratio (mass) of the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group in (S1) is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60. / 40. A mixed solvent containing 50% by mass or more of a solvent not containing a hydroxyl group is particularly preferred from the viewpoint of coating uniformity.
The mixing ratio (mass) of the solvent having an ester structure and the solvent having a ketone structure in (S2) is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 40/60 to 80. / 20. A mixed solvent containing 50% by mass or more of a solvent having an ester structure is particularly preferable from the viewpoint of coating uniformity.
The mixing ratio (mass) of the solvent having an ester structure and the solvent having a lactone structure in (S3) is 70/30 to 99/1, preferably 80/20 to 99/1, more preferably 90/10 to 99. / 1. A mixed solvent containing 70% by mass or more of a solvent having an ester structure is particularly preferable from the viewpoint of stability over time.
In mixing the solvent having an ester structure, the solvent having a lactone structure, and the solvent containing a hydroxyl group in (S4), the solvent having an ester structure is 30 to 80% by mass and the solvent having a lactone structure is 1 to 20% by mass. It is preferable to contain 10 to 60% by mass of a solvent containing a hydroxyl group.
When mixing the solvent having an ester structure, the solvent having a carbonate structure, and the solvent containing a hydroxyl group in (S5), the solvent having an ester structure is 30 to 80% by mass, and the solvent having a carbonate structure is 1 to 20% by mass. It is preferable to contain 10 to 60% by mass of a solvent containing a hydroxyl group.
When mixing the solvent having an ester structure, the solvent having a ketone structure, and the solvent having a lactone structure in (S6), 30 to 80% by mass of the solvent having an ester structure and 10 to 60% by mass of the solvent having a ketone structure. %, And preferably 1 to 20% by mass of a solvent containing a lactone structure.

<Other additives>
If necessary, the photosensitive composition of the present invention may further contain a dye, a plasticizer, a surfactant other than the fluorine and / or silicon surfactant, a photosensitizer, and the like.

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

  These surfactants may be added alone or in some combination.

(Pattern formation method)
The photosensitive composition of the present invention is used by dissolving the above components in a predetermined organic solvent, preferably the above mixed solvent, filtering the solution, and then applying the solution on a predetermined support as follows. The filter used for filter filtration is preferably made of polytetrafluoroethylene, polyethylene or nylon having a pore size of 0.1 microns or less, more preferably 0.05 microns or less, and still more preferably 0.03 microns or less.

  For example, an arbitrary thickness (usually 50 to 500 nm) is applied by a suitable coating method such as a spinner or a coater on a substrate (eg, silicon / silicon dioxide coating) on which a photosensitive composition is used for manufacturing a precision integrated circuit device. Apply with. After application, the resist film is formed by drying by spinning or baking. The bake temperature can be set as appropriate, but is usually 60 to 150 ° C, and preferably 90 to 130 ° C.

Next, exposure is performed through a mask or the like for pattern formation.
Although an exposure amount can be set suitably, it is 1-100 mJ / cm < ² > normally. After exposure, preferably, spinning or / and baking is performed, development and rinsing are performed to obtain a pattern.

  Exposure (immersion exposure) may be performed by filling a liquid (immersion medium) having a higher refractive index than air between the photosensitive film and the lens during irradiation with actinic rays or radiation. Thereby, resolution can be improved. As the immersion medium to be used, any liquid can be used as long as it has a higher refractive index than air, but pure water is preferred.

  In order to prevent the immersion medium and the photosensitive film from coming into direct contact with each other during the immersion exposure, an overcoat layer may be further provided on the photosensitive film. Thereby, the elution of the composition from the photosensitive film to the immersion medium is suppressed, and development defects are reduced.

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

Before forming the photosensitive film, an antireflection film may be coated on the substrate in advance.
As the antireflection film, any of an inorganic film type such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, and amorphous silicon, and an organic film type made of a light absorber and a polymer material can be used. In addition, as the organic antireflection film, commercially available organic antireflection films such as DUV30 series, DUV-40 series manufactured by Brewer Science, AR-2, AR-3, AR-5 manufactured by Shipley are also used. it can.

In the development step, an alkaline developer is used as follows. As an alkaline developer of the resist composition, inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, Secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like Alkaline aqueous solutions such as quaternary ammonium salts, cyclic amines such as pyrrole and pihelidine can be used.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 14.0.

The photosensitive composition of the present invention may be applied to a multilayer resist process (particularly a three-layer resist process). The multilayer resist method includes the following processes.
(a) A lower resist layer made of an organic material is formed on a substrate to be processed.
(b) On the lower resist layer, an intermediate layer and an upper resist layer made of an organic material that crosslinks or decomposes upon irradiation are sequentially laminated.
(c) After forming a predetermined pattern in the upper resist layer, the intermediate layer, the lower layer and the substrate are sequentially etched.
As the intermediate layer, organopolysiloxane (silicone resin) or SiO ₂ coating solution (SOG) is generally used. As the lower layer resist, an appropriate organic polymer film is used,
Various known photoresists may be used. For example, each series of the Fuji Film Arch FH series, FHi series, or Sumitomo Chemical PFI series can be illustrated.
The film thickness of the lower resist layer is preferably 0.1 to 4.0 μm, more preferably 0.2 to 2.0 μm, and particularly preferably 0.25 to 1.5 μm. A thickness of 0.1 μm or more is preferable from the viewpoint of antireflection and dry etching resistance, and a thickness of 4.0 μm or less is preferable from the viewpoint of aspect ratio and pattern collapse of the formed fine pattern.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to this. In addition, Example 8, 21, and 30 shall be read as a reference example.

Synthesis Example 1 (Synthesis of Compound (I-1))
5 g of trifluoromethanesulfonamide was dissolved in 50 ml of water, and 2.7 g of sodium hydroxide was added thereto. Under ice cooling, 3.8 g of methanesulfonyl chloride was added dropwise thereto. The reaction was allowed to proceed at room temperature for 5 hours, and to this was added 4.6 g of triphenylsulfonium bromide dissolved in 10 ml of methanol / 50 ml of water. The supernatant was removed and the oil was dissolved in chloroform. This was washed with water, concentrated, and washed with diisopropyl ether to obtain 2 g of Compound (I-1).
¹ H-NMR (CDCl ₃ )
δ 3.1 (s, 3H), δ 7.6 to 7.8 (m, 15H)

Other components (A) were synthesized using the same method.
The structures of the compounds (I-1) to (I-9) as the component (A) are shown below.

Synthesis Example 2 (Synthesis of resin (RA-1))
Under a nitrogen stream, 8.4 g of cyclohexanone was placed in a three-necked flask and heated to 80 ° C. To this, 6.8 g of γ-butyrolactone methacrylate, 4.7 g of 3-hydroxyadamantyl-1-methacrylate, 9.4 g of 2-methyl-2-adamantyl methacrylate, and 13 mol of polymerization initiator V-60 (manufactured by Wako Pure Chemical Industries) with respect to the monomer % Was dissolved in 75 g of cyclohexanone dropwise over 6 hours. After completion of dropping, the reaction was further carried out at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then added dropwise over 20 minutes to a mixed solution of methanol 900 m / water 100 ml. The precipitated powder was collected by filtration and dried to obtain 178 g of Resin (RA-1). The weight average molecular weight of the obtained resin was 6300 in terms of standard polystyrene, and the dispersity (Mw / Mn) was 1.60.

Resins (RA-2) to (RA-12) were synthesized using the same method. The weight average molecular weight was adjusted by changing the amount of the polymerization initiator.
Hereinafter, the structures of the resins (RA-1) to (RA-12), the molar ratio of repeating units, the weight average molecular weight, and the degree of dispersion are shown.

Examples 1-13 and Comparative Examples 1-2
<Resist preparation>
The components shown in Table 1 below were dissolved in a solvent to prepare a solution having a solid content concentration of 6% by mass, and this was filtered through a polyethylene filter having a pore size of 0.03 microns to prepare a positive resist solution. The prepared positive resist solution was evaluated by the following method, and the results are also shown in Table 1.
<Resist evaluation>
An anti-reflective coating DUV-42 manufactured by Brewer Science Co., Ltd. was uniformly applied to 600 angstroms on a silicon substrate subjected to hexamethyldisilazane treatment with a spin coater, dried on a hot plate at 100 ° C. for 90 seconds, and then at 190 ° C. Heat drying was performed for 240 seconds. Thereafter, each positive resist solution was applied by a spin coater and dried at 120 ° C. for 60 seconds to form a 160 nm resist film.
The resist film was exposed with an ArF excimer laser stepper (NA = 0.75, dipole manufactured by ASML) through a mask, and heated on a hot plate at 120 ° C. for 60 seconds immediately after the exposure. Further, the resist film was developed with an aqueous 2.38 mass% tetramethylammonium hydroxide solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and then dried to obtain a line pattern.

(Exposure latitude)
The exposure amount that reproduces a line-and-space mask pattern with a line width of 80 nm is set as the optimal exposure amount, and when the exposure amount is changed, an exposure amount width that allows the pattern size to be 80 nm ± 10% is obtained, and this value is the optimal exposure. Divided by the amount and expressed as a percentage. The larger the value, the smaller the change in performance due to the change in exposure amount, and the better the exposure latitude.

(PEB temperature dependence)
The exposure amount that reproduces the line-and-space 1/1 with a mask size of 80 nm when post-heated at 120 ° C. for 90 seconds is the optimum exposure amount, and after performing exposure at the optimum exposure amount, Post-heating was performed at two temperatures of + 2 ° C. and −2 ° C. (122 ° C., 118 ° C.), and the obtained line and space were measured to determine their line widths L ₁ and L ₂ . The PEB temperature dependency was defined as the fluctuation of the line width per PEB temperature change of 1 ° C., and was calculated by the following formula.
PEB temperature dependency (nm / ° C.) = | L ₁ −L ₂ | / 4
The smaller the value, the smaller the performance change with respect to the temperature change.

  Hereinafter, abbreviations in the table are shown.

  [Acid generator]

[Basic compounds]
TPSA: triphenylsulfonium acetate DIA: 2,6-diisopropylaniline TEA: triethanolamine PBI: 2-phenylbenzimidazole TMEA: tris (methoxyethoxyethyl) amine PEA: N-phenyldiethanolamine [surfactant]
W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based) W-4: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.) (silicon-based)
〔solvent〕
S1: Propylene glycol methyl ether acetate S2: 2-heptanone S3: Cyclohexanone S4: γ-butyrolactone S5: Propylene glycol methyl ether S6: Ethyl lactate S7: Propylene carbonate

  From Table 1, it can be seen that the photosensitive composition of the present invention is excellent in exposure latitude and PEB temperature dependency.

Examples 14 to 26 and Comparative Example 3
<Resist preparation>
0.2 g of the following surface hydrophobized resin (Polymer-A) was added to the components of Examples 1 to 13 and Comparative Example 2 in Table 1, and dissolved in a solvent to prepare a solution having a solid content concentration of 5% by mass. A positive resist solution was prepared by filtration through a polyethylene filter having a pore size of 0.03 μm. The prepared positive resist solution was evaluated by the following method. The receding contact angle of pure water of the resist film was 65 to 75 ° when the composition was applied with a spin coater and dried at 120 ° C. for 60 seconds to form a 160 nm resist film.
<Resolution evaluation>
Except for using an ArF excimer laser immersion scanner (NA = 0.85) and performing immersion exposure using ultrapure water as the immersion liquid, exposure latitude is obtained using the same method as in Examples 1-13. The PEB temperature dependency was evaluated. The results are shown in Table 2 below.

  From Table 2, it can be seen that the photosensitive composition of the present invention is excellent in exposure latitude and PEB temperature dependency in immersion exposure.

Examples 27-32 and Comparative Examples 4-5
<Resist preparation>
The components shown in Tables 3 to 4 below were dissolved in a solvent and filtered through a polyethylene filter having a pore size of 0.03 μm to prepare a positive resist solution having a solid content concentration of 14% by mass. The prepared positive resist solution was evaluated by the following method, and the results are shown in Tables 3-4.
<Resist evaluation>
The prepared positive resist solution is uniformly coated on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 90 seconds to obtain a 0.4 μm resist. A film was formed.
The resist film was subjected to pattern exposure using a line and space mask using a KrF excimer laser stepper (NA = 0.63), and heated on a hot plate at 110 ° C. for 90 seconds immediately after the exposure. Further, the resist film was developed with an aqueous 2.38 mass% tetramethylammonium hydroxide solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and then dried to form a line pattern.

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

(PEB temperature dependence)
The exposure amount that reproduces a line and space 1/1 with a mask size of 130 nm when post-heated at 110 ° C. for 90 seconds is the optimal exposure amount, and after performing exposure at the optimal exposure amount, Post-heating was performed at two temperatures of + 2 ° C. and −2 ° C. (112 ° C., 108 ° C.), and the obtained line and space were measured to determine their line widths L ₁ and L ₂ . The PEB temperature dependency was defined as the fluctuation of the line width per PEB temperature change of 1 ° C., and was calculated by the following formula.
PEB temperature dependency (nm / ° C.) = | L ₁ −L ₂ | / 4
The smaller the value, the smaller the performance change with respect to the temperature change.

  Hereinafter, abbreviations in the table are shown.

  [Acid generator]

〔resin〕
The structures of the resins (R-4), (R-7), (R-8), and (R-16), the molar ratio of repeating units, the weight average molecular weight, and the degree of dispersion are shown.

  [Basic compounds]

From Tables 3-4, it turns out that the photosensitive composition of this invention is excellent in exposure latitude and PEB temperature dependence.

Examples 33 and 34 and Comparative Example 6
<Resist preparation>
The components shown in Table 5 below were dissolved in a solvent to prepare a solution having a solid content concentration of 6% by mass, and then filtered through a polytetrafluoroethylene filter having a pore size of 0.1 μm to prepare a positive resist solution.

<Resist evaluation>
The prepared positive resist solution is uniformly coated on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 60 seconds to form a 150 nm resist film. Formed.
〔sensitivity〕
This resist film is irradiated with an electron beam projection lithography apparatus (acceleration voltage 100 keV) manufactured by Nikon Corporation, and is subjected to surface exposure while changing the exposure amount by 1 μC / cm ^{2 in} the range of 0 to 30 μC / cm ² , and further at 110 ° C. Baked for 90 seconds. Thereafter, development was performed using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH), and an exposure amount at which the film thickness became 0 was determined by fitting.
[Exposure latitude (%) (EL)]
In the line-and-space one-to-one exposure, the line width is expressed as a change rate of the exposure amount required for the line width to change by 10% on the basis of 150 nm.
[PEB temperature dependence]
In the one-to-one line-and-space exposure when post-heating is performed at 110 ° C. for 90 seconds, the line width is 150 nm as a reference, and then the exposure is performed at the exposure amount, and then the post-heating temperature is + 2 ° C. and − Post-heating was performed at two temperatures of 2 ° C. (112 ° C. and 108 ° C.), and the obtained line and space were measured, and their line widths L ₁ and L ₂ were obtained. The PEB temperature dependency was defined as the fluctuation of the line width per PEB temperature change of 1 ° C., and was calculated by the following formula.
PEB temperature dependency (nm / ° C.) = | L ₁ −L ₂ | / 4
The smaller the value, the smaller the performance change with respect to the temperature change.

From Table 5, it can be seen that a photosensitive composition having a good balance between sensitivity and EL and excellent PEB temperature dependence can be obtained by the present invention.
Similar effects were also obtained in EUV and X-ray lithography.

Claims (7)

(A) a compound that generates an acid represented by the following general formula (I) by irradiation with actinic rays or radiation, and (B) a resin that decomposes by the action of the acid and increases solubility in an alkali developer. The photosensitive composition characterized by the above-mentioned.

In general formula (I),
Ra represents an alkyl group substituted with a fluorine atom or an aryl group substituted with a fluorine atom or a group having a fluorine atom.
Rb is an alkyl group in which the α-position is not substituted with a fluorine atom, and is a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, an alkyl group combining these, or a group having a fluorine atom or a fluorine atom. Represents an unsubstituted aryl group. Rb is an alkyl group that is not substituted with a fluorine atom at the α-position, and a linear, branched, or cyclic alkyl group having 1 to 30 carbon atoms or an alkyl group that is a combination of these is an alkoxy group, an alkoxy group as a substituent It may have a carbonyl group, a cyano group or an oxo group.   The photosensitive composition according to claim 1, wherein the component (A) is a sulfonium salt compound or an iodonium salt compound having an anion of an acid represented by the general formula (I).   The photosensitive composition according to claim 1, wherein the component (B) is a resin having a hydroxystyrene repeating unit. (B) Component is resin which has a repeating unit shown by the following general formula (PA), The photosensitive composition of any one of Claims 1-3 characterized by the above-mentioned.

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

In general formulas (pI) to (pV),
R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group.
Z represents an atomic group necessary for forming a cycloalkyl group together with a carbon atom.
R ₁₂ to R ₁₆ each independently represents a linear or branched alkyl group having 1 to 4 carbon atoms, or represents a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms , or a cycloalkyl group. Either a linear or branched alkyl group having 1 to 4 carbon atoms of R _19, R _21, or represents a cycloalkyl group.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms , or a cycloalkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.   (B) Component is resin which has a lactone structure, The photosensitive composition of any one of Claims 1-4 characterized by the above-mentioned.   The photosensitive film | membrane formed with the photosensitive composition of any one of Claims 1-5.   A pattern forming method comprising: exposing and developing the photosensitive film according to claim 6.