JP2005266766A - Photosensitive composition, compound used for the photosensitive composition, and method for forming pattern using the photosensitive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition, a compound and a method for forming a pattern to obtain a pattern with few pattern collapses, reduced line edge roughness and having pattern profile. <P>SOLUTION: The photosensitive composition contains a compound which generates an acid, expressed by general Formula (I) or (I') by the irradiation of actinic rays or radiation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photosensitive composition whose properties change upon reaction with actinic rays or radiation, a compound used in the photosensitive composition, and a pattern forming method using the photosensitive composition. More specifically, a photosensitive composition used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, a further photofabrication process, a lithographic printing plate, an acid curable composition, and the photosensitivity. The present invention relates to a compound used in the composition and a pattern forming method using the photosensitive composition.

  The chemically amplified resist composition generates an acid in the exposed area by irradiation with radiation such as far ultraviolet light, and the acid-catalyzed reaction changes the solubility of the active radiation irradiated area and non-irradiated area in the developer. And a pattern forming material for forming 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 an exposure light source, the compound having an aromatic group exhibits a large absorption in the 193 nm region. It wasn't.
For this reason, an ArF excimer laser resist containing a resin having an alicyclic hydrocarbon structure has been developed.

Conventionally, compounds that generate perfluoroalkanesulfonic acids such as trifluoromethanesulfonic acid and nonafluorobutanesulfonic acid have been used as photoacid generators. In addition, a photosensitive composition containing a compound that generates a specific sulfonic acid (see, for example, Patent Documents 1 to 3), and a compound that generates a specific sulfonic acid and an acid that decomposes and acts in an alkaline developer. A photosensitive composition containing a resin whose solubility is increased (see, for example, Patent Documents 4 and 5) has been proposed.
Patent Document 6 also describes a photoacid generator containing a sulfonate anion having a fluorinated hydrocarbon.

  However, there are still many insufficient points, and various improvements are desired. For example, prevention of pattern collapse and reduction of line edge roughness are desired.

JP 2003-140332 A European Patent Application No. 1270553 International Publication No. 02/042845 Pamphlet JP 2002-131897 A JP 2002-214774 A US Patent Application Publication No. 2004/0087690

An object of the present invention is to provide a photosensitive composition that hardly causes pattern collapse and can reduce line edge roughness, a compound used in the photosensitive composition, and a pattern forming method using the photosensitive composition. .

  The present invention has the following configuration, whereby the above object of the present invention is achieved.

  (1) A photosensitive composition comprising a compound capable of generating an acid represented by the following general formula (I) or (I ′) by irradiation with actinic rays or radiation.

In general formulas (I) and (I ′),
A ₁ represents a divalent linking group.
A ₂ and A ₃ each independently represents a single bond, an oxygen atom or —N (Rx) —.
Rx represents a hydrogen atom, an aryl group, an alkyl group or a cycloalkyl group.
A ₄ represents a single bond or —C (═O) —.
Ra represents a hydrogen atom or an organic group.
n represents 2 or 3.
Rb represents an n-valent linking group.
When A ₃ is —N (Rx) —, Ra and Rx or Rb and Rx may combine to form a ring.

(2) The photosensitive composition (positive type) as described in (1) above, further comprising (B) a resin that decomposes by the action of an acid and increases the solubility in an alkaline developer.

(3) The above (1), further comprising (D) a resin soluble in an alkali developer and (E) an acid crosslinking agent that crosslinks with the resin soluble in the alkali developer by the action of an acid. The photosensitive composition as described in (negative type).

(4) A compound which generates an acid represented by the general formula (I) or (I ′) described in the above (1) by irradiation with an actinic ray or radiation.

(5) The onium salt of a sulfonic acid represented by (I) or (I ′), wherein the compound that generates an acid represented by the general formula (I) or (I ′) by irradiation with actinic rays or radiation, or The compound according to (4) above, which is any one of sulfonic acid ester compounds represented by (I) or (I ′).

(6) The sulfonic acid represented by the above general formula (I) or (I ′) or a salt thereof (for example, onium salt, metal salt).

(7) The positive photosensitive composition as described in (2) above, wherein the resin (B) has a hydroxystyrene structural unit.

(8) The positive photosensitive composition as described in (2) above, wherein the resin (B) contains a repeating unit having a monocyclic or polycyclic hydrocarbon structure.

(9) The resin (B) is a resin containing a repeating unit having an alcoholic hydroxyl group, decomposed by the action of an acid, and increased in solubility in an alkaline developer. A positive photosensitive composition.

(10) In the above (9), the repeating unit having an alcoholic hydroxyl group in (B) is a repeating unit containing one kind selected from a monohydroxyadamantane structure, a dihydroxyadamantane structure or a trihydroxyadamantane structure. The positive photosensitive composition as described.

(11) The positive photosensitive composition as described in (2) above, wherein (B) is a resin containing a repeating unit having a lactone structure.

(12) The positive photosensitive composition as described in (2) above, wherein the resin (B) is a resin containing at least one methacrylic ester repeating unit and at least one acrylate repeating unit. Stuff.

(13) The positive photosensitive composition as described in (2) above, wherein the resin (B) has a fluorine atom in the main chain or side chain.

(14) The positive photosensitive composition as described in (12) above, wherein the resin (B) has a hexafluoro-2-propanol structure.

(15) The above (2), (7) to (7), further comprising (C) a dissolution inhibiting compound having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer. The positive photosensitive composition according to any one of (14).

(16) The above (2), (3), (16) further comprising at least one of a basic compound (F), a fluorine-based surfactant, and a silicon-based surfactant (G). The photosensitive composition in any one of 7)-(14).

(17) The repeating unit having a monocyclic or polycyclic hydrocarbon structure in the resin (B) is selected from 2-alkyl-2-adamantyl (meth) acrylate or dialkyl (1-adamantyl) methyl (meth) acrylate. The photosensitive composition as described in (8) above, which is a repeating unit containing at least one repeating unit, at least one repeating unit having a lactone structure, and at least one repeating unit having a hydroxyl group.

(18) The photosensitive composition as described in (17) above, wherein the resin (B) further contains a repeating unit having a carboxy group.

(19) The component (B) is at least one repeating unit selected from 2-alkyl-2-adamantyl (meth) acrylate or dialkyl (1-adamantyl) methyl (meth) acrylate, and at least one repeating unit having a hydroxystyrene structure. The photosensitive composition as described in (2) above, comprising a seed.

(20) A pattern forming method comprising forming a film from the photosensitive composition according to any one of (1) to (3) and (7) to (19), and exposing and developing the film. .

  According to the present invention, it is possible to provide a photosensitive composition that hardly causes pattern collapse and can reduce line edge roughness, a pattern forming method using the same, and a compound useful for the photosensitive composition.

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

  The positive photosensitive composition of the present invention, more preferably the positive resist composition, comprises a compound (A) that generates an acid represented by the general formula (I) or (I ′) upon irradiation with actinic rays or radiation, and Contains a resin (B) that decomposes by the action of an acid and increases the solubility in an alkali developer, and further increases the solubility in an alkali developer by further decomposition by the action of an acid, if necessary. Contains the following dissolution inhibiting compound (C), or generates an acid represented by the general formula (I) or (I ′) upon irradiation with actinic rays or radiation, and is soluble in an alkali developer. A resin (D) and a dissolution inhibiting compound (C) having a molecular weight of 3000 or less, which decomposes by the action of an acid and increases the solubility in an alkaline developer.

    The negative photosensitive composition of the present invention, more preferably the negative resist composition is a compound (A) that generates an acid represented by the general formula (I) or (I ′) by irradiation with actinic rays or radiation, A resin (D) soluble in an alkali developer and an acid crosslinking agent (E) that crosslinks the resin soluble in the alkali developer by the action of an acid are contained.

[1] (A) Compound capable of generating an acid represented by the following general formula (I) or (I ′) upon irradiation with actinic rays or radiation The photosensitive composition of the present invention comprises A compound that generates a sulfonic acid represented by the general formula (I) or (I ′) (also referred to as “compound (A)”) is contained.

In general formulas (I) and (I ′),
A ₁ represents a divalent linking group.
A ₂ and A ₃ each independently represents a single bond, an oxygen atom or —N (Rx) —.
Rx represents a hydrogen atom, an aryl group, an alkyl group or a cycloalkyl group.
A ₄ represents a single bond or —C (═O) —.
Ra represents a hydrogen atom or an organic group.
n represents 2 or 3.
Rb represents an n-valent linking group.
When A ₃ is —N (Rx) —, Ra and Rx or Rb and Rx may combine to form a ring.

The divalent linking group as A ₁ is preferably an organic group having 1 to 20 carbon atoms, more preferably an alkylene group (preferably having 1 to 10 carbon atoms, more preferably 2 to 6 carbon atoms, still more preferably. C3-4). The alkylene chain may have a linking group such as an oxygen atom, a sulfur atom, a —C (═O) — group or an ester group.
The divalent linking group as A ₁ is more preferably an alkylene group substituted with a fluorine atom, and particularly preferably an alkylene group in which 30 to 100% of the hydrogen atoms are substituted with a fluorine atom. In the case of an alkylene group substituted with a fluorine atom, the carbon atom bonded to the —SO ₃ H group preferably has a fluorine atom. Further, a perfluoroalkylene group is preferable, and a perfluoroethylene group, a perfluoropropylene group, and a perfluorobutylene group are most preferable.

  The aryl group in the Rx group may have a substituent and is preferably an aryl group having 6 to 14 carbon atoms, and examples thereof include a phenyl group and a naphthyl group.

  The alkyl group as Rx may have a substituent, and is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and has an oxygen atom, a sulfur atom, or a nitrogen atom in the alkyl chain. May be. Specifically, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-dodecyl group, n-tetradecyl group, n-octadecyl group, etc. And a branched alkyl group such as isopropyl group, isopropyl group, isobutyl group, t-butyl group, neopentyl group, 2-ethylhexyl group.

  Examples of the alkyl group having a substituent include groups in which a linear or branched alkyl group is substituted with a cycloalkyl group (for example, an adamantylmethyl group, an adamantylethyl group, a cyclohexylethyl group, a camphor residue, etc.). .

  The cycloalkyl group as Rx may have a substituent, preferably a cycloalkyl group having 3 to 20 carbon atoms, and may have an oxygen atom in the ring. Specific examples include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, an adamantyl group, and the like.

Ra represents a hydrogen atom or a monovalent organic group.
The monovalent organic group as Ra preferably has 1 to 20 carbon atoms, and examples thereof include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group.

  The alkyl group, cycloalkyl group or aryl group as Ra is the same as those exemplified as Rx.

  The aralkyl group as Ra is preferably an aralkyl group having 7 to 20 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, a naphthylmethyl group, and a naphthylethyl group.

  Examples of the alkenyl group as Ra include a group having a double bond at an arbitrary position of the alkyl group mentioned as Rx.

The n-valent linking group as Rb preferably has 1 to 20 carbon atoms. When n = 2 in the general formula (I ′), the divalent linking group as Rb is, for example, an alkylene group (preferably having 1 to 20 carbon atoms) or an arylene group (preferably having 6 to 10 carbon atoms). , An aralkylene group (preferably having a carbon number of 7 to 13) and an alkenylene group (preferably having a carbon number of 2 to 12). These may have a substituent.
Examples of the trivalent linking group as Rb when n = 3 include a trivalent group excluding any hydrogen atom of the divalent linking group.

  Examples of the substituent that each group may have include, for example, a halogen atom, a hydroxyl group, a nitro group, a cyano group, a carboxy group, a carbonyl group, a cycloalkyl group (preferably having 3 to 20 carbon atoms), and an aryl group (preferably Has 6 to 14 carbon atoms, an alkoxy group (preferably 1 to 20 carbon atoms), an acyl group (preferably 2 to 20 carbon atoms), an acyloxy group (preferably 2 to 20 carbon atoms), an alkoxycarbonyl group (preferably C2-C20), an aminoacyl group (preferably C2-C20) etc. are mentioned. As for the cyclic structure in the aryl group, cycloalkyl group and the like, examples of the substituent further include an alkyl group (preferably having a carbon number of 1 to 20). As for the aminoacyl group, examples of the substituent further include 1 or 2 alkyl groups (preferably having 1 to 20 carbon atoms).

  The sulfonic acids of the general formulas (I) and (I ′) are preferably sulfonic acids represented by the following general formulas (IA) to (IC) and (I′A) to (I′C).

In general formulas (IA) to (IC) and (I′A) to (I′C),
Ra ′ has the same meaning as Ra in formula (I).
Rb and n are synonymous with Rb and n in the general formula (I ′).
Ra ″ represents an alkyl group, an aryl group, an aralkyl group or an alkenyl group.
Rx ′ has the same meaning as Rx in formulas (I) and (I ′).
n1 represents an integer of 1 to 10.
n2 represents an integer of 0 to 10.
A ₅ represents an alkylene group or an arylene group.

The alkylene group as A ₅ is preferably an alkylene group or a cycloalkylene group not substituted with fluorine.
In formula (IA), Ra ′ and Rx ′ are preferably bonded to form a ring. By forming the ring structure, the stability is improved, and the storage stability of the composition using the ring structure is improved. The ring to be formed preferably has 4 to 20 carbon atoms, may be monocyclic or polycyclic, and may contain an oxygen atom, a sulfur atom, or a nitrogen atom in the ring.

  Examples of the monocyclic structure include a 4-membered ring, a 5-membered ring, a 6-membered ring, a 7-membered ring and an 8-membered ring containing a nitrogen atom. Examples of the polycyclic structure include a structure composed of a combination of 2 or 3 or more monocyclic structures. These rings may contain an oxygen atom or a sulfur atom. The monocyclic structure and polycyclic structure may have a substituent, for example, a halogen atom, a hydroxyl group, a cyano group, a carboxy group, a carbonyl group, a cycloalkyl group (preferably having 3 to 10 carbon atoms), an aryl Group (preferably 6 to 14 carbon atoms), alkoxy group (preferably 1 to 10 carbon atoms), acyl group (preferably 2 to 15 carbon atoms), acyloxy group (preferably 2 to 15 carbon atoms), alkoxycarbonyl group (Preferably 2 to 15 carbon atoms), aminoacyl group (preferably 2 to 20 carbon atoms) and the like are preferable. As for the cyclic structure in the aryl group, cycloalkyl group and the like, the substituent is more preferably an alkyl group (preferably having a carbon number of 1 to 15). As for the aminoacyl group, 1 or 2 alkyl groups (preferably having 1 to 15 carbon atoms) are further preferred as a substituent.

Examples of the alkyl group, aryl group, aralkyl group or alkenyl group as Ra ″ include the same as the alkyl group, aryl group, aralkyl group or alkenyl group as Ra.
n1 + n2 is preferably 2-8, more preferably 2-6.

  Preferred specific examples of the sulfonic acid represented by the general formula (I) or (I ′) are shown below, but the present invention is not limited thereto.

  (A) As a compound which generates the sulfonic acid represented by the general formula (I) or (I ′) upon irradiation with actinic rays or radiation, the sulfonic acid represented by the general formula (I) or (I ′) One selected from a sulfonium salt compound or an iodonium salt compound or one selected from an ester compound of a sulfonic acid represented by (I) or (I ′) is preferred, and more preferably the following general formulas (A1) to ( It is a compound represented by A5).

In the general formula (A1), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a sulfonate anion from which a —SO ₃ H hydrogen atom of the sulfonate of formula (I) or (I ′) is removed.
The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.
The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (A1a), (A1b) and (A1c) described later.
In addition, the compound which has two or more structures represented by general formula (A1) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (A1) is at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (A1) It may be a compound.

  More preferred components (A1) include compounds (A1a), (A1b), and (A1c) described below.

Compound (A1a) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (A1), 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 with the remaining being an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include a triarylsulfonium compound, a diarylalkylsulfonium compound, and an aryldialkylsulfonium compound.
The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
As the alkyl group that the arylsulfonium compound has as necessary, a linear or branched alkyl group having 1 to 15 carbon atoms is preferable. For example, 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. Moreover, as a cycloalkyl group, C3-C15 is preferable, a cyclopropyl group, a cyclobutyl group,
Examples thereof include 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), an aryl group (for example, 6 to 14 carbon atoms), an alkoxy group (for example, 1 to 15 carbon atoms), You may have a halogen atom, a hydroxyl group, and a phenylthio group as a substituent. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, most preferably carbon. These are an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

  Next, the compound (A1b) will be described.

Compound (A1b) is a compound in the case where R _{201 to} R ₂₀₃ in formula (A1) each independently represents an organic group containing no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.
The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
R ₂₀₁ to R ₂₀₃ each independently, preferably an alkyl group, a cycloalkyl group, an optionally straight have a double bond in the chain, branched, cyclic oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group A vinyl group, more preferably a linear, branched, cyclic 2-oxoalkyl group, and most preferably a linear, branched 2-oxoalkyl group.
The alkyl group as R _{201 to} R ₂₀₃ may be either linear or branched, and is preferably a linear or branched alkyl group having 1 to 20 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, Butyl group, pentyl group).
The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is C3-10 is preferred, for example, a cyclopentyl group, a cyclohexyl group and a norbornyl group.
The 2-oxoalkyl group as R _{201 to} R ₂₀₃ may be linear, branched or cyclic, and preferably includes a group having> C═O at the 2-position of the above alkyl group. it can.
The alkoxy group in the alkoxycarbonylmethyl group as R ₂₀₁ to R _203, preferred examples include an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, butyl group, pentyl group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.
Two members out of R _{201 to} R ₂₀₃ may combine to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

  The compound (A1c) is a compound represented by the following general formula (A1c), and is a compound having an arylacylsulfonium salt structure.

In general formula (A1c),
_R213 represents an aryl group which may be substituted, and is preferably a phenyl group or a naphthyl group.
Preferred examples of the substituent include an alkyl group on R _213, cycloalkyl group, alkoxy group, acyl group, a nitro group, a hydroxyl group, an alkoxycarbonyl group and a carboxy group.
R ₂₁₄ and R ₂₁₅ represent a hydrogen atom, an alkyl group, or a cycloalkyl group.
Y ₂₀₁ and Y ₂₀₂ are each independently an alkyl group (in particular, a substituted alkyl group can include a 2-oxoalkyl group, an alkoxycarbonylalkyl group, and a carboxyalkyl group), a cycloalkyl group, an aryl group, or vinyl. Represents a group.
_R213 and _R214 , _R214 and _R215 , _Y201 and _Y202 may be bonded to each other to form a ring structure. These ring structures may contain an oxygen atom, a sulfur atom, an ester bond, or an amide bond.
Alkyl group as Y ₂₀₁ and Y ₂₀₂ is preferably a linear or branched alkyl group having 1 to 20 carbon atoms.
The cycloalkyl group as R ₂₁₄ , R ₂₁₅ , Y ₂₀₁ and Y ₂₀₂ is preferably a cycloalkyl group having 3 to 20 carbon atoms.
Examples of the 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group as Y ₂₀₁ and Y ₂₀₂ .
The alkoxycarbonyl group in the alkoxycarbonylalkyl group is preferably an alkoxycarbonyl group having 2 to 20 carbon atoms.
Examples of the group formed by combining Y ₂₀₁ and Y ₂₀₂ include a butylene group and a pentylene group.
Y ₂₀₁ and Y ₂₀₂ are preferably an alkyl group having 4 or more carbon atoms, more preferably an alkyl group having 4 to 16, and still more preferably 4 to 12.
Further, at least one of R ₂₁₄ or R ₂₁₅ is preferably an alkyl group, and more preferably both R ₂₁₄ and R ₂₁₅ are alkyl groups.

In general formula (A2),
X ⁻ represents a sulfonate anion from which a —SO ₃ H hydrogen atom of the sulfonate of formula (I) or (I ′) is removed.
_R204 and _R205 each independently represents an aryl group, an alkyl group or a cycloalkyl group.
The aryl group for R ₂₀₄ and R ₂₀₅ is preferably a phenyl group or a naphthyl group, more preferably a phenyl group.
The alkyl group as R ₂₀₄ and R ₂₀₅ may be either linear or branched and is preferably a linear 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 cycloalkyl group as R ₂₀₄ and R ₂₀₅ is C3-10 is preferred, for example, a cyclopentyl group, a cyclohexyl group and a norbornyl group.
Examples of the substituent that each group as R ₂₀₄ and R ₂₀₅ may have include, for example, an alkyl group (for example, 1 to 15 carbon atoms), an aryl group (for example, 6 to 15 carbon atoms), an alkoxy group (for example, C1-15), a halogen atom, a hydroxyl group, a phenylthio group, etc. can be mentioned.

In general formulas (A3) to (A5), X ₁ represents a monovalent group formed by removing the —SO ₃ H hydrogen atom of the sulfonic acid of general formula (I) or (I ′).

  In General Formula (A3), A represents an alkylene group, an alkenylene group, or an arylene group, and preferably has 1 to 6 carbon atoms.

In general formula (A4),
R ₂₀₈ represents an alkyl group, a cycloalkyl group, or an aryl group.
R ₂₀₉ represents an alkyl group (particularly an oxoalkyl group as a substituted alkyl group), a cycloalkyl group, a cyano group or an alkoxycarbonyl group, preferably a halogen-substituted alkyl group or a cyano group.
The alkyl group or cycloalkyl group as R ₂₀₈ and R _{209 is the same} as the alkyl group or cycloalkyl group as R ₂₀₄ and R ₂₀₅ .
The aryl group as R _{208 is the same} as the aryl group as R ₂₀₄ and R ₂₀₅ .
Alkoxycarbonyl group as R ₂₀₉ is preferably 2 to 11 carbon atoms, and examples thereof include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, and butoxycarbonyl group.

In general formula (A5),
R ₂₁₀ and R ₂₁₁ represent a hydrogen atom, an alkyl group, a cycloalkyl group, a cyano group, a nitro group or an alkoxycarbonyl group, preferably a halogen-substituted alkyl group, a nitro group or a cyano group.
_R212 represents a hydrogen atom, an alkyl group, a cycloalkyl group, a cyano group or an alkoxycarbonyl group.
The alkyl group or cycloalkyl group as R _{210 to} R _{212 is the same} as the alkyl group or cycloalkyl group as R ₂₀₄ and R ₂₀₅ described above.
The alkoxycarbonyl group as R _{212 is the same} as the alkoxycarbonyl group as R ₂₀₉ .

  Of the general formulas (A1) to (A5), preferred are compounds represented by the general formula (A1), and more preferred are compounds represented by the general formulas (A1a) to (A1c).

  (A) Although the preferable specific example of the compound which generate | occur | produces the acid represented by general formula (I) or (I ') by actinic light or a radiation is given below, this invention is not limited to these.

The sulfonic acid represented by the general formula (I) or (I ′) or a salt thereof (for example, an onium salt or a metal salt) can be synthesized by using a general sulfonic acid esterification reaction or sulfonamidation reaction. For example, after selectively reacting one sulfonyl halide portion of a bissulfonyl halide compound with an amine, alcohol, or amide compound to form a sulfonamide bond, a sulfonate bond, or a sulfonimide bond, It can be obtained by a method of hydrolyzing a sulfonyl halide moiety or a method of opening a cyclic sulfonic anhydride with an amine, alcohol, or amide compound.
Examples of the sulfonic acid salt represented by the general formula (I) or (I ′) include sulfonic acid metal salts and sulfonic acid onium salts. As a metal in the metal salt of sulfonic acid, Na ⁺
, Li ⁺ , K ^{+ and the} like. Examples of the onium cation in the sulfonic acid onium salt include an ammonium cation, a sulfonium cation, an iodonium cation, a phosphonium cation, and a diazonium cation.
The sulfonic acid represented by the general formula (I) or (I ′) or a salt thereof is a synthesis of a compound that generates the sulfonic acid represented by the general formula (I) or (I ′) by irradiation with actinic rays or radiation. Can be used.

  The compound which generates the sulfonic acid represented by the general formula (I) or (I ′) upon irradiation with actinic rays or radiation is obtained by converting the sulfonic acid represented by the general formula (I) or (I ′) into a sulfonium salt or iodonium. By salt exchange with a photoactive onium salt such as a salt, or by forming an ester of sulfonic acid represented by the above general formula (I) or (I ′) with nitrobenzyl alcohol, N-hydroxyimide, oxime compound Can be synthesized.

The content in the photosensitive composition of the present invention the compound (A), based on the total solids of the composition, preferably from 0.1 to 20 wt%, more preferably 0.5 to 10 mass%, more preferably Is 1-7 mass%.

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

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

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

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

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

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

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

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

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

  A non-nucleophilic anion is an anion having a remarkably low ability to cause a nucleophilic reaction, and is an anion capable of suppressing degradation with time due to an intramolecular nucleophilic reaction. This improves the temporal stability of the resist.

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

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

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

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

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

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

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

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

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

  Examples of the sulfonylimide anion include saccharin anion.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The alkyl group and cycloalkyl group of R _{201 to} R ₂₀₃ are preferably those having 1 to 1 carbon atoms.
Examples include 0 straight chain or branched alkyl groups (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group) and cycloalkyl groups having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group). it can. More preferred examples of the alkyl group include a 2-oxoalkyl group and an alkoxycarbonylmethyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  Component (B) used in the present invention is decomposed with an acid into an alkali-soluble resin, as disclosed in European Patent No. 254853, JP-A-2-25850, JP-A-3-223860, JP-A-4-251259 and the like. It is possible to obtain an alkali-soluble resin monomer having a group capable of being decomposed or reacting with an acid-decomposable group by copolymerization with various monomers.

Specific examples of the component (B) used in the present invention are shown below, but the present invention is not limited thereto.
pt-butoxystyrene / p-hydroxystyrene copolymer,
p- (t-butoxycarbonyloxy) styrene / p-hydroxystyrene copolymer,
p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene copolymer,
4- (t-butoxycarbonylmethyloxy) -3-methylstyrene / 4-hydroxy-3-methylstyrene copolymer,
p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene (10% hydrogenated) copolymer,
m- (t-butoxycarbonylmethyloxy) styrene / m-hydroxystyrene copolymer,
o- (t-butoxycarbonylmethyloxy) styrene / o-hydroxystyrene copolymer,
p- (cumyloxycarbonylmethyloxy) styrene / p-hydroxystyrene copolymer,
Cumyl methacrylate / methyl methacrylate copolymer,
4-t-butoxycarbonylstyrene / dimethyl maleate copolymer,
Benzyl methacrylate / tetrahydropyranyl methacrylate copolymer,
p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene / styrene copolymer,
pt-butoxystyrene / p-hydroxystyrene / fumaronitrile copolymer,
t-butoxystyrene / hydroxyethyl methacrylate copolymer,
Styrene / N- (4-hydroxyphenyl) maleimide / N- (4-t-butoxycarbonyloxyphenyl) maleimide copolymer,
p-hydroxystyrene / t-butyl methacrylate copolymer,
Styrene / p-hydroxystyrene / t-butyl methacrylate copolymer,
p-hydroxystyrene / t-butyl acrylate copolymer,
Styrene / p-hydroxystyrene / t-butyl acrylate copolymer,
p- (t-butoxycarbonylmethyloxy) styrene / p-hydroxystyrene / N-methylmaleimide copolymer,
t-butyl methacrylate / 1-adamantyl methyl methacrylate copolymer,
p-hydroxystyrene / t-butyl acrylate / p-acetoxystyrene copolymer, p-hydroxystyrene / t-butyl acrylate / p- (t-butoxycarbonyloxy) styrene copolymer,
p-hydroxystyrene / t-butyl acrylate / p- (t-butoxycarbonylmethyloxy) styrene copolymer,

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

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

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

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

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

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

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

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

  The -Y group;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The total amount of the repeating units represented by the general formulas (XV) to (XVII) and other repeating units is generally 0 to 70 mol%, preferably 10 to 6 with respect to all repeating units constituting the resin.
It is used in the range of 0 mol%, more preferably 20-50 mol%.

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

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

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

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

[3] (C) Dissolution-inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as “(C) component” or “dissolution-inhibiting compound”) that is decomposed by the action of an acid to increase the solubility in an alkaline developer.
(C) As a dissolution-inhibiting compound having a molecular weight of 3000 or less that decomposes by the action of an acid and increases its solubility in an alkaline developer, the permeability of 220 nm or less is not lowered, so Proceeding of SPIE, 2724, 355 (1996) An alicyclic or aliphatic compound containing an acid-decomposable group is preferred, such as a cholic acid derivative containing an acid-decomposable group described in (1). Examples of the acid-decomposable group and alicyclic structure are the same as those described above for the alicyclic hydrocarbon-based acid-decomposable resin.

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

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

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

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

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

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

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

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

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

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

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

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

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

Any crosslinking agent can be used as long as it is a compound that crosslinks a resin that is soluble in an alkaline developer by the action of an acid.
(1) Hydroxymethyl, alkoxymethyl, and acyloxymethyl forms of phenol derivatives.
(2) A compound having an N-hydroxymethyl group, an N-alkoxymethyl group, or an N-acyloxymethyl group.
(3) A compound having an epoxy group.

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

  Of these crosslinking agents, particularly preferred are listed below.

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

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

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

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

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

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

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

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

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

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

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

  Examples of commercially available surfactants that can be used include 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, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

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

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

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

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

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

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

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

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

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

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

  A preferable addition amount of these dissolution promoting compounds is 2 to 50% by mass, and more preferably 5 to 30% by mass with respect to the resin of the component (B) or the resin of the component (D). The amount is preferably 50% by mass or less from the viewpoint of suppressing development residue and preventing pattern deformation during development.

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

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

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

  These surfactants may be added alone or in several combinations.

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

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

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

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

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

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

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, the content of this invention is not limited by this.

(Synthesis of Compound I-1)
I-1: 1,1,2,2,3,3-hexafluoro-3- (piperidine-1-sulfonyl) propane-1-sulfonic acid triphenylsulfonium (Triphenylsulfonium-1,1,2,2,3,3 -hexafluoro-3- (piperidine-1-sulfonyl) -propane-1-sulfonate)

  Under a nitrogen stream, 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonyldifluoride 4.0 g (12.65 mmol), triethylamine 2.56 g (25.3 mmol), diisopropyl ether 30 mL Was cooled with ice, and a mixed solution of 1.08 g (12.6 mmol) of piperidine and 15 mL of diisopropyl ether was added dropwise thereto over 30 minutes. The mixture was stirred for 1 hour under ice cooling, and further stirred at room temperature for 1 hour. The organic layer was washed successively with water, a saturated aqueous ammonium chloride solution and water, and the organic layer was dried over sodium sulfate. The solvent was removed, 20 mL of ethanol and 200 mg of sodium hydroxide were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution to obtain an ethanol solution of sulfonic acid represented by the following formula.

The triphenylsulfonium acetate solution was added to the sulfonic acid solution and stirred at room temperature for 2 hours. 300 mL of chloroform was added, and the organic layer was washed successively with water, a saturated aqueous ammonium chloride solution, and water. Purification by column chromatography (SiO ₂ , chloroform / methanol = 5/1) gave 3.0 g (4.68 mmol) of a white solid.
The triphenylsulfonium acetate solution was added with 5.07 g (13 mmol) of triphenylsulfonium iodide, 2.25 g (13.5 mmol) of silver acetate, 120 mL of acetonitrile and 60 mL of water and stirred at room temperature for 1 hour, and the reaction solution was filtered. Prepared.

¹ H-NMR (300 MHz, CDCl ₃ ) δ 1.64 (bs, 6H), 3.29 (bs, 2H), 3.64 (bs, 2H), 7.70 (m, 15H)
¹⁹ F-NMR (300 MHz, CDCl ₃ ) δ-111.1 (t, 2F), -114.3 (t, 2F), -119.4 (m, 2F)

(Synthesis of Compound I-15)
Under nitrogen flow, 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonyldifluoride 4.0 g (12.65 mmol), triethylamine 2.56 g (25.3 mmol), tetrahydrofuran 40 mL were ice-cooled. Then, a mixed solution of piperidine 1.08 g (12.6 mmol) and tetrahydrofuran 20 mL was added dropwise thereto over 30 minutes. The mixture was stirred for 1 hour under ice-cooling, and further stirred at room temperature for 3 hours. Ethyl acetate was added, and the organic layer was washed successively with water, saturated aqueous ammonium chloride solution and water, and dried over sodium sulfate. The solvent was removed, ethanol (20 mL) and sodium hydroxide (200 mg) were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution, and thereto was added 1- (3,3-dimethyl-2-oxobutyl) -tetrahydrothiophenium bromide (3.21 g), and the mixture was stirred at room temperature for 2 hours. 300 mL of chloroform was added, and the organic layer was washed several times with water and dried to obtain 2.79 g of the desired white solid.
¹ H-NMR (300 MHz, CDCl ₃ ) δ 1.245 (s, 9H), 1.658 (bs, 6H), 2.280 (m, 2H), 2.505 (m, 2H), 3.291 (bs, 2H), 3.607 (m , 6H), 5.028 (s, 2H)
¹⁹ F-NMR (300 MHz, CDCl3) δ −111.62 (t, 2F), −114.36 (t, 2F), −119.43 (s, 2F)

(Synthesis of Compound I-46)
Under nitrogen flow, 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonyldifluoride 4.0 g (12.65 mmol), triethylamine 2.56 g (25.3 mmol), tetrahydrofuran 40 mL were ice-cooled. Then, a mixed solution of 1.04 g (11.9 mmol) of morpholine and 20 mL of tetrahydrofuran was added dropwise thereto over 30 minutes. The mixture was stirred for 1 hour under ice-cooling, and further stirred at room temperature for 3 hours. Ethyl acetate was added, and the organic layer was washed successively with water, saturated aqueous ammonium chloride solution and water, and dried over sodium sulfate. The solvent was removed, 20 mL of ethanol and 600 mg of sodium hydroxide were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution, and 4.09 g of triphenylsulfonium bromide was added thereto, followed by stirring at room temperature for 2 hours. 300 mL of chloroform was added, the organic layer was washed several times with water, and the solvent was removed to obtain 6.0 g of the desired white solid.
¹ H-NMR (300 MHz, CDCl ₃ ) δ 3.54 (bs, 4H), 3.74 (bs, 4H), 7.657-7.773 (m, 15H)
¹⁹ F-NMR (300 MHz, CDCl ₃ ) δ −110.74 (m, 2F), −114.33 (t, 2F), −119.32 (s, 2F)

(Synthesis of Compound I-85)
1,1,2,2,3,3-Hexafluoropropane-1,3-disulfonyldifluoride 10.0 under nitrogen flow
g (31.6 mmol), triethylamine 3.2 g (31.6 mmol), and tetrahydrofuran 100 mL were ice-cooled, and N, N-diethylnipecotamide 5.8 g (31.6 mmol) and tetrahydrofuran 80 were added thereto.
A mixed solution of mL was added dropwise over 30 minutes. The mixture was stirred for 1 hour under ice-cooling, and further stirred at room temperature for 3 hours. Ethyl acetate was added, and the organic layer was washed successively with water, saturated aqueous ammonium chloride solution and water, and dried over sodium sulfate. The solvent was removed, 100 mL of methanol and 1600 mg of sodium hydroxide were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution. To this, 9.76 g of triphenylsulfonium bromide was added and stirred at room temperature for 2 hours. 300 mL of chloroform was added, the organic layer was washed several times with water, and the solvent was removed to obtain 16.0 g of the desired colorless oil.
¹ H-NMR (300 MHz, CDCl ₃ ) δ 1.09 (q, 3H), 1.20 (q, 3H), 1.59-1.92 (m, 4H), 2.70
(t, 1H), 3.05 (t, 1H), 3.25 (t, 1H), 3.34 (m, 4H), 3.95 (t, 2H), 7.67-7.78 (m, 15H)
¹⁹ F-NMR (300 MHz, CDCl ₃ ) δ −110.54, -111.91 (m, 2F), −113.99 (m, 2F), −118.45, −119.37 (m, 2F)

(Synthesis of Compound I-89)
Under nitrogen flow, 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonyldifluoride 4.0 g (12.65 mmol), triethylamine 2.56 g (25.3 mmol), tetrahydrofuran 40 mL were ice-cooled. Then, a mixed solution of 2.10 g (11.9 mmol) of 4-cyclohexylphenol and 20 mL of tetrahydrofuran was added dropwise thereto over 30 minutes. The mixture was stirred for 1 hour under ice-cooling, and further stirred at room temperature for 3 hours. Ethyl acetate was added, and the organic layer was washed successively with water, saturated aqueous ammonium chloride solution and water, and dried over sodium sulfate. The solvent was removed, ethanol (20 mL) and sodium hydroxide (200 mg) were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution, and 4.09 g of triphenylsulfonium bromide was added thereto, followed by stirring at room temperature for 2 hours. 300 mL of chloroform was added, and the organic layer was washed several times with water. Purification by column chromatography (SiO ₂ , chloroform / methanol = 5/1) gave 6.65 g of the desired white solid.
¹ H-NMR (300 MHz, CDCl3) δ 1.256-1.607 (m, 5H), 1.724-1.856 (m, 5H), 2.505 (m, 1H), 7.193 (AB quartet, 4H), 7.657-7.773 (m, 15H)
¹⁹ F-NMR (300 MHz, CDCl3) δ −107.78 (m, 2F), −114.33 (t, 2F), −118.73 (s, 2F)

(Synthesis of Compound I-90)
Under nitrogen flow, 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonyldifluoride 4.0 g (12.65 mmol), triethylamine 2.56 g (25.3 mmol), tetrahydrofuran 40 mL were ice-cooled. Then, a mixed solution of 3.62 g (11.9 mmol) of 3-n-pentadecylphenol and 20 mL of tetrahydrofuran was added dropwise thereto over 30 minutes. The mixture was stirred for 1 hour under ice-cooling, and further stirred at room temperature for 3 hours. Ethyl acetate was added, and the organic layer was washed successively with water, saturated aqueous ammonium chloride solution and water, and dried over sodium sulfate. The solvent was removed, ethanol (20 mL) and sodium hydroxide (200 mg) were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution, and 4.09 g of triphenylsulfonium bromide was added thereto, followed by stirring at room temperature for 2 hours. 300 mL of chloroform was added, and the organic layer was washed several times with water. Purification by column chromatography (SiO ₂ , chloroform / methanol = 5/1) gave 3.84 g of the desired white solid.
¹ H-NMR (300 MHz, CDCl ₃ ) δ 0.876 (t, 3H), 1.253-1.294 (m, 24H), 1.62 (m, 2H),
2.63 (m, 2H), 7.05-7.16 (m, 3H), 7.27 (m, 1H), 7.68-7.75 (m, 15H)
¹⁹ F-NMR (300 MHz, CDCl ₃ ) δ −107.55 (m, 2F), −114.01 (m, 2F), δ −118.40 (m, 2F)

(Synthesis of Compound I-93)
Under nitrogen flow, 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonyldifluoride 4.0 g (12.65 mmol), triethylamine 2.56 g (25.3 mmol), tetrahydrofuran 40 mL were ice-cooled. Then, a mixed solution of 1.35 g (11.9 mmol) of heptamethyleneimine and 20 mL of tetrahydrofuran was added dropwise thereto over 30 minutes. The mixture was stirred for 1 hour under ice-cooling, and further stirred at room temperature for 3 hours. Ethyl acetate was added, and the organic layer was washed successively with water, saturated aqueous ammonium chloride solution and water, and dried over sodium sulfate. The solvent was removed, 20 mL of ethanol and 600 mg of sodium hydroxide were added, and the mixture was stirred at room temperature for 2 hours. Dilute hydrochloric acid was added to neutralize the reaction solution, and 4.09 g of triphenylsulfonium bromide was added thereto, followed by stirring at room temperature for 2 hours. 300 mL of chloroform was added, and the organic layer was washed several times with water. Purification by column chromatography (SiO ₂ , chloroform / methanol = 5/1) gave 1.10 g of the desired white solid.
¹ H-NMR (300 MHz, CDCl ₃ ) δ 1.70 (m, 10H), 3.11 (bs, 2H), 3.82 (bs, 2H), 7.657
-7.773 (m, 15H)
¹⁹ F-NMR (300 MHz, CDCl ₃ ) δ −109.70 (t, 2F), −114.27 (t, 2F), −119.44 (s, 2F)

  The compound which generates an acid represented by the general formula (I) or (I ′) upon irradiation with an actinic ray or radiation of the present invention can be synthesized by the same method as described above.

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

<Fluorine group-containing resin>
Hereinafter, the structures of the fluorine group-containing resins (FII-1) to (FII-10) used in the examples are shown.

  Table 1 below shows the weight average molecular weights of the fluorine group-containing resins (FII-1) to (FII-10).

[Examples Ar1 to Ar30 and Comparative Example ar1]

<Resist preparation>
The components shown in Table 2 below were dissolved in a solvent to prepare a solution having a solid content concentration of 12% by mass, and this was filtered through a 0.1 μm polytetrafluoroethylene filter or a polyethylene filter to prepare a positive resist solution. The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 2.

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

Pattern collapse evaluation method:
The exposure amount that reproduces a 130 nm line and space 1: 1 mask pattern is the optimum exposure amount, and when the dense pattern of line and space 1: 1 is exposed at the optimum exposure amount, the pattern does not collapse at a finer mask size. The line width to be resolved was defined as the limit pattern collapse line width. A smaller value indicates that a finer pattern is resolved without falling, and pattern falling is less likely to occur.

Line edge roughness evaluation method:
The line edge roughness is measured by observing a 130 nm line-and-space 1: 1 pattern using a length-measuring scanning electron microscope (SEM), and a reference line that should have an edge in the range where the longitudinal edge of the line pattern is 5 μm. The distance from was measured 50 points with a length measurement SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated. A smaller value indicates better performance.

  Abbreviations common to Table 2 and Tables 3, 4, 6, and 7 below are summarized below.

[Acid generator]
PAG-A: Triphenylsulfonium nonafluorobutane sulfonate

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

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

〔solvent〕
A1: Propylene glycol monomethyl ether acetate A2: 2-heptanone A3: Cyclohexanone A4: γ-butyrolactone B1: Propylene glycol monomethyl ether B2: Ethyl lactate

  From the results in Table 2, it is clear that in the ArF exposure, the photosensitive composition of the present invention has little pattern collapse, can reduce the line edge roughness, and has an excellent pattern profile.

[Examples Si-1 to Si-8 and Comparative Example si-1]
(1) Formation of lower resist layer FHi-028DD resist (resist for i-line manufactured by Fuji Film Orin) was applied to a 6-inch silicon wafer using a spin coater Mark8 manufactured by Tokyo Electron, and baked at 90 ° C. for 90 seconds to form a film. A uniform film having a thickness of 0.55 μm was obtained.
This was further heated at 200 ° C. for 3 minutes to form a lower resist layer having a thickness of 0.40 μm.

(2) Formation of the upper resist layer The components shown in Table 3 below are dissolved in a solvent to prepare a solution having a solid content of 11% by mass, and the solution is precisely filtered through a membrane filter having a diameter of 0.1 μm to prepare an upper resist composition. did.
The upper resist composition was similarly applied onto the lower resist layer and heated at 130 ° C. for 90 seconds to form an upper resist layer having a thickness of 0.20 μm.

  Resins (SI-1) to (SI-5) in Table 3 are as follows.

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

Pattern collapse evaluation method:
The exposure amount that reproduces a 120 nm line and space 1: 1 mask pattern is the optimum exposure amount, and when the dense pattern of line and space 1: 1 is exposed at the optimum exposure amount, the pattern does not collapse at a finer mask size. The line width to be resolved was defined as the limit pattern collapse line width.

Line edge roughness evaluation method:
The line edge roughness is measured by using a length-measuring scanning electron microscope (SEM) to observe a 120 nm line-and-space 1: 1 pattern, and a reference line that should have an edge in a range where the longitudinal edge of the line pattern is 5 μm. The distance from was measured 50 points with a length measurement SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated.

  The results are shown in Table 3.

  From the results in Table 3, it is clear that the photosensitive composition of the present invention has little pattern collapse, can reduce line edge roughness, and has an excellent pattern profile even when used as a two-layer resist.

[Examples F2-1 to F2-13 and Comparative Example f2-1]
<Resist preparation>
The components shown in Table 4 below were dissolved in a solvent to prepare a solution having a solid content concentration of 5% by mass, and this was filtered through a 0.1 μm polyethylene filter to prepare a resist solution.
Each resist solution was applied to a silicon wafer subjected to hexamethyldisilazane treatment by a spin coater and dried by heating on a vacuum contact hot plate at 120 ° C. for 90 seconds to obtain a resist film having a thickness of 120 nm.
The obtained resist film was subjected to pattern exposure using an F ₂ excimer laser stepper (157 nm), and immediately after the exposure, it was heated on a hot plate at 120 ° C. for 90 seconds. The sample was developed with a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds and rinsed with pure water to obtain a sample wafer. About these, pattern collapse and line edge roughness were evaluated.

Pattern collapse evaluation method:
The exposure amount that reproduces the 80 nm line and space 1: 1 mask pattern is the optimum exposure amount, and the exposure amount is increased from the optimum exposure amount. The width was defined as the limit pattern collapse line width.

Line edge roughness evaluation method:
The line edge roughness is measured by using a length-measuring scanning electron microscope (SEM) to observe a 120 nm line-and-space 1: 1 pattern, and a reference line that should have an edge in a range where the longitudinal edge of the line pattern is 5 μm. The distance from was measured 50 points with a length measurement SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated.

  The evaluation results are shown in Table 4.

From the results in Table 4, it is clear that the photosensitive composition of the present invention also has little pattern collapse, low line edge roughness, and excellent pattern profile even in F ₂ excimer laser exposure.

[Examples KrP-1 to KrP-14 and Comparative Example krp-1]
<Resist preparation>
The components shown in Table 6 below were dissolved in a solvent and filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a positive resist solution having a solid content concentration of 14% by mass.
The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 6.

Table 5 below shows the molar ratios and weight average molecular weights of the resins (R-2) to (R-27) in Table 6. The repeating units constituting the resins (R-2) to (R-27) are those exemplified above.

<Resist evaluation>
The prepared positive resist solution is uniformly coated on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 90 seconds to obtain a 0.4 μm resist. A film was formed.
The resist film was subjected to pattern exposure using a line and space mask using a KrF excimer laser stepper (NA = 0.63), and heated on a hot plate at 110 ° C. for 90 seconds immediately after the exposure. Further developed with 2.38 mass% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, dried to form line patterns, and these patterns collapsed and the line edge roughness was evaluated. did.

Pattern collapse evaluation method:
The exposure amount that reproduces a 150 nm line and space 1: 1 mask pattern is the optimum exposure amount, and when the dense pattern of line and space 1: 1 is exposed at the optimum exposure amount, the pattern does not collapse at a finer mask size. The line width to be resolved was defined as the limit pattern collapse line width.

Line edge roughness evaluation method:
The line edge roughness is measured by using a length-measuring scanning electron microscope (SEM) to observe a 150 nm line-and-space 1: 1 pattern, and a reference line that should have an edge in a range where the longitudinal edge of the line pattern is 5 μm. The distance from was measured 50 points with a length measurement SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated.

  The evaluation results are shown in Table 6.

  From the results in Table 6, it is clear that the photosensitive composition of the present invention has little pattern collapse, can reduce the line edge roughness, and has an excellent pattern profile as a positive resist composition in KrF excimer laser exposure. is there.

[Examples KrN-1 to KrN-14 and Comparative Example krn-1]
<Resist preparation>
The components shown in Table 7 below were dissolved in a solvent, and this was filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a negative resist solution having a solid concentration of 14% by mass.
The prepared negative resist solutions were evaluated in the same manner as in Examples KrP-1 to KrP-10 and Comparative Example krp-1, and the results are shown in Table 7.

  The structure, molecular weight, and molecular weight distribution of the alkali-soluble resin in Table 7 are shown below.

  The structure of the crosslinking agent in Table 7 is shown below.

  From the results of Table 7, it can be seen that the photosensitive composition of the present invention has less pattern collapse, lower line edge roughness, and excellent pattern profile, even as a negative resist composition in KrF excimer laser exposure. it is obvious.

[Examples EBP-1 to EBP-14 and Comparative Example ebp-1]
<Resist preparation>
The components shown in Table 6 above were dissolved in a solvent, and this was filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a positive resist solution having a solid content concentration of 12% by mass.
The prepared positive resist solution was evaluated by the following method, and the results are shown in Table 8.

<Resist evaluation>
The prepared positive resist solution is uniformly applied on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 60 seconds to obtain a 0.3 μm resist. A film was formed.
This resist film was irradiated with an electron beam projection lithography apparatus (acceleration voltage 100 keV) manufactured by Nikon Corporation, and immediately after the irradiation, it was heated on a hot plate at 110 ° C. for 90 seconds. Further, development was performed at 23 ° C. for 60 seconds using an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass, rinsed with pure water for 30 seconds, and then dried to form a line and space pattern.

Pattern collapse evaluation method:
The exposure dose that reproduces a line and space of 1: 1 with a mask size of 100 nm is set as the optimal exposure dose, and the line width that resolves without collapsing the pattern at a finer mask size when irradiated with the optimal exposure dose is the limit pattern collapse line width It was.

Line edge roughness evaluation method:
The line edge roughness is measured by using a length-measuring scanning electron microscope (SEM) to observe a 100 nm line-and-space 1: 1 pattern, and a reference line that should have an edge in a range where the longitudinal edge of the line pattern is 5 μm. The distance from was measured 50 points with a length measurement SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated.

  From the results of Table 8, it is clear that the photosensitive composition of the present invention has little pattern collapse, can reduce the line edge roughness, and has an excellent pattern profile even as a positive resist composition in electron beam irradiation. .

[Examples EBN-1 to EBN-14 and Comparative Example ebn-1]
<Resist preparation>
The components shown in Table 7 above were dissolved in a solvent and filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a negative resist solution having a solid content concentration of 12% by mass.
The prepared negative resist solution was evaluated by the following method, and the results are shown in Table 9.

<Resist evaluation>
The prepared negative resist solution is uniformly applied on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 60 seconds to obtain a 0.3 μm resist. A film was formed.
This resist film was irradiated with an electron beam projection lithography apparatus (acceleration voltage 100 keV) manufactured by Nikon Corporation, and immediately after the irradiation, it was heated on a hot plate at 110 ° C. for 90 seconds. Further, development was performed at 23 ° C. for 60 seconds using an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass, rinsed with pure water for 30 seconds, and then dried to form a line and space pattern.

Pattern collapse evaluation method:
The dose that reproduces the mask size of 100 nm line / 150 nm space was the optimum dose, and the line width at which the pattern was resolved without falling when the mask was irradiated with the optimum dose was defined as the limit pattern collapse line width.

Line edge roughness evaluation method:
The line edge roughness is measured by observing a 100 nm line / 150 nm space pattern using a length measuring scanning electron microscope (SEM), and the distance from the reference line where the longitudinal edge of the line pattern should be 5 μm. Was measured with a length measurement SEM (Hitachi, Ltd. S-8840) to obtain a standard deviation, and 3σ was calculated.

  From the results shown in Table 9, it is clear that the photosensitive composition of the present invention has little pattern collapse, can reduce the line edge roughness, and has an excellent pattern profile as a negative resist composition in electron beam irradiation. .

[Examples EUVP-1 to EUVP-14 and comparative example euvp-1]
The components shown in Table 6 were dissolved in a solvent, and this was filtered through a 0.1 μm polytetrafluoroethylene filter to prepare a positive resist solution with a solid content concentration of 8% by mass, and evaluated as follows. .

<Resist evaluation>
The prepared positive resist solution is uniformly applied on a silicon substrate subjected to hexamethyldisilazane treatment using a spin coater, and is heated and dried on a hot plate at 120 ° C. for 60 seconds to obtain a 0.15 μm resist. A film was formed. The resulting resist film was subjected to surface exposure using EUV light (wavelength 13 nm) while changing the exposure amount by 0.5 mJ in the range of 0 to 10.0 mJ, and further baked at 110 ° C. for 90 seconds. Thereafter, using a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution, the dissolution rate at each exposure amount was measured to obtain a sensitivity curve. In this sensitivity curve, the exposure amount when the dissolution rate of the resist is saturated was taken as sensitivity, and the dissolution contrast (γ value) was calculated from the gradient of the linear portion of the sensitivity curve. The larger the γ value, the better the dissolution contrast.
The evaluation results are shown in Table 10 below.

  From the results of Table 10, it can be seen that the composition of the present invention is superior in sensitivity and high contrast and superior in comparison with the composition of the comparative example in the property evaluation by irradiation with EUV light.

(Immersion exposure)
<Resist preparation>
The components of Examples Ar1 to Ar30 were dissolved in a solvent to prepare a solution having a solid concentration of 7% by mass, and this was filtered through a 0.1 μm polyethylene filter to prepare a positive resist solution. The prepared positive resist solution was evaluated by the following method.

<Resolution evaluation>
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The prepared resist composition was applied thereon, and baked at 115 ° C. for 60 seconds to form a 150 nm resist film. The wafer thus obtained was subjected to two-beam interference exposure (wet exposure) using pure water as the immersion liquid. In the two-beam interference exposure (wet), as shown in FIG. 1, a laser 1, an aperture 2, a shutter 3, three reflecting mirrors 4, 5, 6 and a condenser lens 7 are used, and a prism 8, liquid The wafer 10 having an antireflection film and a resist film was exposed through an immersion liquid (pure water) 9. The wavelength of the laser 1 was 193 nm, and the prism 8 forming a 65 nm line and space pattern was used. Immediately after exposure, the resist pattern obtained by heating at 115 ° C. for 90 seconds, developing with an aqueous tetramethylammonium hydroxide solution (2.38 mass%) for 60 seconds, rinsing with pure water, and spin drying is then used for the scanning pattern. When observed using an electron microscope (S-9260 manufactured by Hitachi), a 65 nm line and space pattern was resolved.
The composition of the present application has a good image forming ability even in an exposure method through an immersion liquid.

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

Explanation of symbols

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

Claims (6)

(A) A photosensitive composition comprising a compound that generates an acid represented by the following general formula (I) or (I ′) upon irradiation with an actinic ray or radiation.
In general formulas (I) and (I ′),
A ₁ represents a divalent linking group.
A ₂ and A ₃ each independently represents a single bond, an oxygen atom or —N (Rx) —.
Rx represents a hydrogen atom, an aryl group, an alkyl group or a cycloalkyl group.
A ₄ represents a single bond or —C (═O) —.
Ra represents a hydrogen atom or an organic group.
n represents 2 or 3.
Rb represents an n-valent linking group.
When A ₃ is —N (Rx) —, Ra and Rx or Rb and Rx may combine to form a ring.   The photosensitive composition according to claim 1, further comprising (B) a resin that decomposes under the action of an acid and increases the solubility in an alkaline developer.   2. The photosensitivity according to claim 1, further comprising (D) a resin soluble in an alkali developer and (E) an acid crosslinking agent that crosslinks with the resin soluble in the alkali developer by the action of an acid. Composition.   A compound that generates an acid represented by the general formula (I) or (I ') according to claim 1 by irradiation with an actinic ray or radiation. A sulfonic acid represented by the general formula (I) or (I ′) or a salt thereof.
In general formulas (I) and (I ′),
A ₁ represents a divalent linking group.
A ₂ and A ₃ each independently represents a single bond, an oxygen atom or —N (Rx) —.
Rx represents a hydrogen atom, an aryl group, an alkyl group or a cycloalkyl group.
A ₄ represents a single bond or —C (═O) —.
Ra represents a hydrogen atom or an organic group.
n represents 2 or 3.
Rb represents an n-valent linking group.
When A ₃ is —N (Rx) —, Ra and Rx or Rb and Rx may combine to form a ring. A pattern forming method comprising the steps of: forming a photosensitive film from the photosensitive composition according to claim 1; and exposing and developing the photosensitive film.