JP2005077811A - Photosensitive composition and method for forming pattern by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition improved in PEB (post exposure baking) temperature dependence and line edge roughness and to provide a method for forming a pattern by using the composition. <P>SOLUTION: The photosensitive composition contains: (A) a compound which generates an aromatic sulfonic acid or an aliphatic sulfonic acid having the alpha site not substituted by a fluorine atom, by irradiation with active rays; and (B) resin which has a monocyclic or polycyclic hydrocarbon structure and at least one kind of repeating unit derived from an acrylate, has 70 to 150°C glass transition temperature and the solubility with an alkaline developing solution increased by the effect of an acid. The method for forming pattern is carried out by using the composition. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to 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, a radical curable composition, and the like. The present invention relates to a pattern forming method using

  The photosensitive composition is a composition that generates an acid or a radical upon irradiation with actinic rays and changes the physical properties of the site stimulated by the reaction, and more preferably, the irradiated portion and the non-irradiated portion of the actinic ray This is a pattern forming material that changes the solubility of the developer in the developing solution to form a pattern on the substrate.

  Examples of such a photosensitive composition include a chemically amplified resist composition containing an acid generator that generates an acid upon irradiation with actinic rays.

  As a chemically amplified resist composition, EP-A-1020767 describes a photosensitive composition containing a resin having an alicyclic structure and a photoacid generator for generating perfluoroalkanesulfonic acid. .

  However, the conventional resist composition has been required to further improve the PEB temperature dependency and the line edge roughness.

  For example, when a wafer having a large diameter is used, it has been found that temperature variations in heating (PEB) using a hot plate after exposure affect the resulting pattern. Improvement is desired.

  Further, the conventional resist composition has a problem that the resolution of the pattern is hindered by factors such as the edge roughness of the line pattern. Here, the edge roughness means that the top and bottom edges of the resist line pattern irregularly fluctuate in the direction perpendicular to the line direction due to the characteristics of the resist. Sometimes the edges look uneven.

European Patent Application No. 1020767

  An object of the present invention is to provide a photosensitive composition having improved PEB temperature dependency and line edge roughness, and a pattern forming method using the same.

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

(1) (A) a compound that generates an aromatic sulfonic acid or an aliphatic sulfonic acid in which the alpha position is not substituted with a fluorine atom upon irradiation with actinic rays, and (B) a monocyclic or polycyclic cyclic hydrocarbon structure. And a resin having at least one repeating unit derived from an acrylate derivative and having a glass transition temperature of 70 to 150 ° C., which increases the solubility in an alkali developer by the action of an acid. A photosensitive composition.

  (2) The photosensitive composition as described in (1), wherein the resin as the component (B) has a repeating unit having a lactone group.

  (3) The photosensitive composition as described in (1) or (2), wherein the resin as the component (B) has a repeating unit represented by the following general formula (I).

In the general formula (I), 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.

  (4) A pattern forming method comprising: forming a resist film from the photosensitive composition according to any one of (1) to (3); and exposing and developing the resist film.

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

  (5) The photosensitive composition as described in (2) or (3), wherein the lactone group is represented by the following general formula (Lc) or (II-1) to (II-4).

In the 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 = 2 to 6.

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

  (6) The resin of component (B) has a repeating unit derived from an allylic acid ester derivative and a repeating unit derived from a methacrylic acid ester derivative (1) to (3) or (5) The photosensitive composition in any one of.

  According to the present invention, a photosensitive composition excellent in line edge roughness and PED temperature dependency can be provided.

  Hereinafter, the present invention will be described in detail.

  In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what does not have a substituent and what has a substituent. . For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

[1] (A) A compound that generates an aromatic sulfonic acid or an aliphatic sulfonic acid in which the alpha position is not substituted with a fluorine atom upon irradiation with actinic rays. The photosensitive composition of the present invention is obtained by irradiation with actinic rays. It contains an aromatic sulfonic acid or a compound that generates an aliphatic sulfonic acid in which the alpha position is not substituted with a fluorine atom (hereinafter also referred to as “acid generator (A)”).

  Examples of compounds that generate an aromatic sulfonic acid or an aliphatic sulfonic acid in which the alpha position is not substituted with a fluorine atom by irradiation with actinic rays include, for example, compounds represented by the following general formulas (ZI) to (ZVII): Can be mentioned.

In the above general formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.

X ⁻ represents an aliphatic sulfonic acid anion or an aromatic sulfonic acid anion, and the aliphatic sulfonic acid is one in which the alpha position of the sulfonic acid is not substituted with a fluorine atom.

The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.

Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.

The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).

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

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

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

The compound (ZI-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (ZI), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.

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

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

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

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

  The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.

Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and alkoxy groups having 1 to 12 carbon atoms, most preferably alkyl having 1 to 4 carbon atoms. Group, a cycloalkyl group having 3 to 6 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.

An aliphatic sulfonate anion in which the carbon atom at the alpha position in the anion portion X ⁻ is not substituted with a fluorine atom is represented by RSO ₃ ⁻ , for example.

  R in the aliphatic sulfonate anion is not limited, and for example, a linear or branched alkyl group having 1 to 20 carbon atoms (methyl group, ethyl group, propyl group, butyl group, etc.) and 3 carbon atoms. ˜20 cycloalkyl groups (cyclohexyl group, norbornanone residue).

  These aliphatic groups may have a substituent unless an aliphatic sulfonate anion in which a fluorine atom is substituted on a carbon atom at the alpha position. Examples of the substituent include an alkyl group, a hydroxyl group, and a halogen atom. Atoms, amino groups, carboxyl groups, cyano groups, oxo groups and the like can be mentioned.

The aromatic sulfonate anion in the anion part X ⁻ is preferably a benzenesulfonate anion.

  The aromatic group in the aromatic sulfonate anion may have a substituent. Examples of the substituent that the aromatic group may have include, for example, a halogen atom (fluorine atom, chlorine atom, etc.), an alkyl group (preferably having 1 to 5 carbon atoms), and a perfluoroalkyl group (preferably having 1 carbon atom). And the like.

  Next, the compound (ZI-2) will be described.

Compound (ZI-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (ZI) each independently represents an organic group containing no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

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

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

The alkyl group as R ₂₀₁ to R ₂₀₃ may be linear, may be either branched, preferably a straight-chain or branched alkyl group (e.g., methyl group having 1 to 20 carbon atoms, an ethyl group, a propyl Group, butyl group, pentyl group). The alkyl group is more preferably a linear or branched 2-oxoalkyl group or an alkoxycarbonylmethyl group. The linear or branched 2-oxoalkyl group is preferably a group having> C═O at the 2-position of the above alkyl group. The linear or branched 2-oxoalkyl group may have a double bond in the chain. The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group).

The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably, and a cycloalkyl group having 3 to 20 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl). The cycloalkyl group is more preferably a 2-oxocycloalkyl group. The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the above cycloalkyl group. The 2-oxocycloalkyl group may have a double bond in the chain.

R _{201 to} R ₂₀₃ are further substituted with a halogen atom, an alkoxy group (for example, 1 to 5 carbon atoms), an alkoxycarbonyl group (for example, 1 to 5 carbon atoms), a ═O group, a hydroxyl group, a cyano group, or a nitro group. Also good.

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

In General Formula (ZI-3), R ₂₁₃ represents an aryl group. R ₂₁₄ and R ₂₁₅ each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group. Y ₂₀₁ and Y ₂₀₂ each independently represents an alkyl group, a cycloalkyl group, an aryl group or a vinyl group. _R213 and _R214 may combine to form a ring structure, _R214 and _R215 may combine to form a ring structure, and _Y201 and _Y202 combine to form a ring structure. May be. These ring structures may contain an oxygen atom, a sulfur atom, an ester bond, or an amide bond.

X- is, in the general formula (ZI) X ^- can be exemplified the same as the anion of.

Aryl group R ₂₁₃ is preferably an aryl group having from 6 to 15 carbon atoms, and examples thereof include a phenyl group, a naphthyl group.

The alkyl group as R ₂₁₄ and R ₂₁₅ may be either linear or branched, and is preferably a linear or branched alkyl group having 1 to 20 carbon atoms (eg, methyl group, ethyl group, propyl group). Group, butyl group, pentyl group).

Preferred examples of the cycloalkyl group as R ₂₁₄ and R ₂₁₅ include cycloalkyl groups having 3 to 20 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group).

The alkyl group as Y ₂₀₁ and Y ₂₀₂ may be 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). Group, butyl group, pentyl group). The alkyl group is more preferably a linear or branched 2-oxoalkyl group or an alkoxycarbonylmethyl group. The linear or branched 2-oxoalkyl group is preferably a group having> C═O at the 2-position of the above alkyl group. The linear or branched 2-oxoalkyl group may have a double bond in the chain. The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group).

Preferred examples of the cycloalkyl group as Y ₂₀₁ and Y ₂₀₂ include cycloalkyl groups having 3 to 20 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group). The cycloalkyl group is more preferably a 2-oxocycloalkyl group. The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the above cycloalkyl group. The 2-oxocycloalkyl group may have a double bond in the chain.

The aryl group of Y ₂₀₁ and Y ₂₀₂ is preferably an aryl group having 6 to 15 carbon atoms, and examples thereof include a phenyl group and a naphthyl 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.

Examples of the group R ₂₁₃ and R _214, R ₂₁₄ and R _215, Y ₂₀₁ and Y ₂₀₂ is formed by bonding, for example, it includes a butylene group and a pentylene group.

R ₂₁₃ , R ₂₁₄ , R ₂₁₅ , Y ₂₀₁ and Y ₂₀₂ may be further substituted with a halogen atom, alkyl group, cycloalkyl group, ═O group, alkoxycarbonyl group, hydroxyl group, cyano group, nitro group or the like. .

In formula _{(ZII), R 204, R} 205 each independently represents an aryl group, an alkyl group or a cycloalkyl group.

In the general formula (ZII), the aryl group of 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 having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group). Group, butyl group, pentyl group).

The cycloalkyl group as R _204, R ₂₀₅ is preferably, and a cycloalkyl group having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, norbornyl).

The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (e.g. having 1 to 10 carbon atoms), an aryl group (e.g. having 6 to 15 carbon atoms), an alkoxy group (for example, 1 to 15 carbon atoms ), Halogen atoms, hydroxyl groups, phenylthio groups, and the like.

X ^- is, X in formula (ZI) ^- can be exemplified the same as the anion of.

In general formulas (ZIII) to (ZVII), Ar ₃ and Ar ₄ each independently represents an aryl group. R ₂₀₆ , R ₂₀₇ and R ₂₀₈ each independently represents an alkyl group or an aryl group. In the case of an alkyl group, the alpha position is an alkyl group not substituted with a fluorine atom. Aryl groups R _208, via a linking group may be bonded to the aryl group of R ₂₀₈ of another compound. R ₂₀₉ represents an alkyl group, a cyano group or an alkoxycarbonyl group, preferably a halogen-substituted alkyl group or a cyano group. A represents an alkylene group, an alkenylene group or an arylene group. R ₂₁₀ and R ₂₁₁ each independently represents a hydrogen atom, an alkyl 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 cyano group or an alkoxycarbonyl group.

  Among the acid generators (A), compounds represented by the general formulas (ZI) to (ZIII) are more preferable.

  Hereinafter, although the specific example of an acid generator (A) is given, this invention is not limited to this.

  The content of the acid generator (A) is generally 0.01 to 10% by mass, preferably 0.1 to 7% by mass, more preferably 0.1 to 5%, based on the total solid content in the composition. % By mass.

Acid generating compound that can be used in combination other than acid generator (A) In the present invention, in addition to the acid generator (A), a compound that decomposes by irradiation with actinic rays to generate an acid may be used in combination.

  The acid generator (A) of the present invention is used in a molar ratio (acid generator (A) / other acid generator) and is usually 100/0 to 20/80. , Preferably 100/0 to 40/60, more preferably 100/0 to 50/50.

  Examples of such acid generators that can be used in combination include photocation polymerization photoinitiators, photoradical polymerization photoinitiators, dye photodecolorants, photochromic agents, and actives used in microresists. Known compounds that generate an acid upon irradiation with light or radiation and mixtures thereof can be appropriately selected and used.

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

  A compound that generates a sulfonic acid having an alpha position substituted with a fluorine atom or a compound that generates a carboxylic acid upon irradiation with actinic rays is preferable.

  Further, a group that generates an acid upon irradiation with actinic rays, or a compound in which a compound is introduced into the main chain or side chain of a polymer, such as 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, JP 63- The compounds described in No. 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.

[2] (B) The action of an acid having a monocyclic or polycyclic hydrocarbon structure and having a repeating unit derived from at least one acrylate derivative and having a glass transition temperature of 70 to 150 ° C. The photosensitive composition of the present invention has a monocyclic or polycyclic hydrocarbon structure, has at least one repeating unit derived from an acrylate derivative, and is a glass. It contains a resin having a transition temperature of 70 to 150 ° C., which increases the solubility in an alkaline developer by the action of an acid (hereinafter also referred to as “acid-decomposable resin”).

  The acid-decomposable resin has a repeating unit having a group (acid-decomposable group) that is insoluble or hardly soluble in an alkali developer and decomposes by the action of an acid to become alkali-soluble.

  The acid-decomposable resin has a monocyclic or polycyclic hydrocarbon structure, and has an acid-decomposable group having an alkali-soluble group protected by a group having a monocyclic or polycyclic hydrocarbon structure. The group having a monocyclic or polycyclic hydrocarbon structure is preferably an alicyclic hydrocarbon group represented by the following general formula (pI) to general formula (pVI).

In the formula, R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z forms an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to do.

R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group.

R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.

R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

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.

  Further, the further substituent of the alkyl group includes an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, A carboxy group, an alkoxycarbonyl group, a nitro group, etc. can be mentioned.

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

  Below, the structural example of an alicyclic part is shown among alicyclic hydrocarbon groups.

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

  Examples of the substituent for these alicyclic hydrocarbon groups include an alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably a substituent selected from the group consisting of a methyl group, an ethyl group, a propyl group, and an isopropyl group. Represent. 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 further substituents such as an alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group.

  Examples of the alkali-soluble group protected by the alicyclic hydrocarbon group represented by the general formulas (pI) to (pVI) 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 (acid-decomposable group) protected by the structure represented by the general formulas (pI) to (pVI) in the resin, groups represented by the following general formulas (pVII) to (pXI) are preferable. Can be mentioned.

Here, R _{11 to} R ₂₅ and Z are the same as defined above.

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

  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 is a single bond, a group selected from the group consisting of an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups. Represents.

  Ra represents any group of the above formulas (pI) to (pVI).

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

  The acid-decomposable resin preferably has an alkali-soluble group protected by a 2-alkyl-2-adamantyl group or 1-adamantyl-1-alkyl group, and is alkali-soluble protected by a 1-adamantyl-1-alkyl group. It is more preferable to have a group.

  The acid-decomposable resin may have an acid-decomposable group as a partial structure having an alicyclic hydrocarbon group represented by the general formula (pI) to the general formula (pVI). The repeating unit may be contained in at least one repeating unit.

As the structure of the acid-decomposable group, in addition to the alkali-soluble group (acid-decomposable group) protected by the structure represented by the general formulas (pI) to (pVI), for example, —C (═O) — it can be exemplified those represented by 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 represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.

  The acid-decomposable resin preferably has a repeating unit having a lactone group.

  The repeating unit having a lactone group is preferably represented by the following general formula (II).

In the general formula (II), R ₁ a represents a hydrogen atom, a halogen atom or an alkyl group. W ₁ represents a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, or a group of two or more groups selected from the group consisting of an ester group. La represents a lactone group represented by the following general formula (Lc) or (II-1) to (II-4).

In the 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 = 2 to 6.

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

In the general formula (II), examples of the halogen atom represented by R _1a include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The alkyl group for R _1a is preferably an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, and a propyl group. The alkyl group for R _1a may have a substituent. Examples of the substituent that the alkyl group represented by R _1a may have include a halogen atom and a cyano group.

In the general formula (II), examples of the alkylene group represented by W ₁ include groups represented by the following formulae.

− [C (Rf) (Rg)] r ₁ −
In the above formula, Rf and Rg represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyl group or an alkoxy group, and both may be the same or different. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably selected from a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of further substituents such as an alkyl group include a hydroxyl group, a halogen atom, an alkoxy group, a carboxyl group, an acyloxy group, a cyano group, an alkyl group, an acetylamide group, an alkoxycarbonyl group, and an acyl group. r ₁ is an integer of 1 to 10.

Examples of the divalent group in the combination of two or more groups in W ₁ include those represented by the following formulae.

In the above formula, R _ab and R _bb represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyl group, and an alkoxy group, and both may be the same or different.

  The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably selected from a methyl group, an ethyl group, a propyl group, and an isopropyl group.

  Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of the substituent such as an alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group having 1 to 4 carbon atoms. r1 represents an integer of 1 to 10, preferably an integer of 1 to 4. m represents an integer of 1 to 3, preferably 1 or 2.

The alkyl group of Ra _{1 to} Re _{1 in} the general formula (Lc) is preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group. Group, sec-butyl group, t-butyl group and the like.

In the general formulas (II-1) to (II-4), the alkyl group in R _{1b to} R _5b is preferably a linear or branched alkyl group having 1 to 12 carbon atoms, more preferably 1 carbon atom. -10 linear or branched alkyl groups, more preferably methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group Hexyl group, heptyl group, octyl group, nonyl group, decyl group.

As a cycloalkyl group in R _<1b > -R < _5b >, C3-C8 things, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, are preferable.

As an alkenyl group in R _<1b > -R < _5b >, C2-C6 things, such as a vinyl group, a propenyl group, a butenyl group, a hexenyl group, are preferable.

The alkyl group in the alkoxycarbonyl group of R _{1b to} R _5b is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, such as a methyl group, ethyl group, propyl group, isopropyl group, n- Examples thereof include a butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group.

Examples of the ring formed by combining two of R _{1b to} R _5b include 3- to 8-membered rings such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring.

In the general formulas (II-1) to (II-4), R _{1b to} R _5b may be connected to any carbon atom constituting the cyclic skeleton.

The alkyl group, cycloalkyl group, alkenyl group, and alkoxycarbonyl group of Ra _{1 to} Re ₁ and R _{1b to} R _5b may have a substituent. Examples of the substituent that the alkyl group, cycloalkyl group, alkenyl group, and alkoxycarbonyl group of Ra _{1 to} Re ₁ and R _{1b to} R _5b may have include an alkoxy group having 1 to 4 carbon atoms, a halogen atom (fluorine Atom, chlorine atom, bromine atom, iodine atom), acyl group having 2 to 5 carbon atoms, acyloxy group having 2 to 5 carbon atoms, cyano group, hydroxyl group, carboxy group, alkoxycarbonyl group having 2 to 5 carbon atoms, nitro group Etc.

  Hereinafter, although the specific example of the monomer corresponded to the repeating unit which has a lactone group represented by general formula (Lc) is shown, it is not limited to these.

  In the specific examples of the monomer, (I-17) to (I-36) are preferable from the viewpoint that the exposure margin becomes better.

  Further, the monomer structure is preferably one having an acrylate structure from the viewpoint of good edge roughness.

  Specific examples of the repeating unit having a lactone group represented by general formulas (II-1) to (II-4) are shown below, but the contents of the present invention are not limited thereto.

  The acid-decomposable resin preferably has a repeating unit represented by the following general formula (I).

In the general formula (I), 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.

In the general formula (I), it is preferable that two of R _{2c to} R _4c are hydroxyl groups.

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

  The acid-decomposable resin can further have a repeating unit represented by the following general formula (III).

In the general formula (III), A ₆ represents a single bond, an alkylene group, a cycloalkylene group, an ether group, a thioether group, a carbonyl group, or a group of two or more groups selected from the group consisting of ester groups.

R _6a represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyano group, or a halogen atom.

In the general formula (III), examples of the alkylene group represented by A ₆ include groups represented by the following formulae.

-[C (Rnf) (Rng)] r-
In the above formula, Rnf and Rng represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyl group, and an alkoxy group, and both may be the same or different. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably selected from a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of further substituents such as an alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. r is an integer of 1-10.

In the general formula (III), examples of the cycloalkylene group represented by A ₆ include those having 3 to 10 carbon atoms, and examples thereof include a cyclopentylene group, a cyclohexylene group, and a cyclooctylene group.

The bridged alicyclic ring containing Z ₆ may have a substituent. Examples of the substituent include a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms), an alkoxycarbonyl group (preferably having 1 to 5 carbon atoms), an acyl group (for example, a formyl group and a benzoyl group), an acyloxy group ( For example, propyl carbonyloxy group, benzoyloxy group), an alkyl group (preferably having from 1 to 4 carbon atoms), a carboxyl group, a hydroxyl group and an alkylsulfonylsulfamoyl group (-CONHSO ₂ CH _3, etc.). In addition, the alkyl group as a substituent may be further substituted with a hydroxyl group, a halogen atom, an alkoxy group (preferably having 1 to 4 carbon atoms), or the like.

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

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

  The acid-decomposable resin may have a repeating unit derived from a methacrylic ester derivative as long as it has a repeating unit derived from at least one acrylate derivative. In the present invention, the repeating unit derived from the acrylate derivative also includes a repeating unit derived from acrylic acid itself.

  The repeating unit derived from the acrylate derivative possessed by the acid-decomposable resin may be any repeating unit constituting the acid-decomposable resin. For example, the repeating unit represented by the general formula (pA), the general formula The repeating unit represented by (I), the repeating unit represented by general formula (II), the repeating unit represented by general formula (III), and the repeating unit by the following acrylic ester can be mentioned.

  In addition to the above repeating units, the acid-decomposable resin adjusts dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required properties of resist, such as resolution, heat resistance, and sensitivity. It can have various repeating units for the purpose.

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

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

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

  Specifically, the following monomers can be mentioned.

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

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

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

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

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

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

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

Dialkyl itaconates:
Dimethyl itaconate, diethyl itaconate, dibutyl itaconate, etc.

  Dialkyl esters or monoalkyl esters of fumaric acid; dibutyl fumarate and the like.

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

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

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

  The content of the repeating unit having a partial structure containing an alicyclic hydrocarbon group represented by the general formulas (pI) to (pVI) is preferably 30 to 70 mol%, more preferably, based on all repeating units. It is 35-65 mol%, More preferably, it is 40-60 mol%.

  The content of the repeating unit represented by the general formula (I) is preferably from 5 to 50 mol%, more preferably from 10 to 40 mol%, still more preferably from 15 to 35 mol%, based on all repeating units. .

  The content of the repeating unit represented by the general formula (II) is preferably 20 to 70 mol%, more preferably 25 to 60 mol%, based on all repeating units.

  The content of the repeating unit derived from the acrylate derivative is preferably at least 20 mol%, more preferably at least 40 mol%, based on all repeating units.

  An acid-decomposable resin containing both a repeating unit derived from an acrylate derivative and a repeating unit derived from a methacrylic acid ester derivative is preferred, and more preferably derived from a repeating unit derived from an acrylate derivative and a methacrylic acid ester derivative. It is an acid-decomposable resin consisting only of repeating units. A preferable ratio of acrylic acid ester / methacrylic acid ester is 20/80 to 100/0, more preferably 30/70 to 90/10, and still more preferably 40/60 to 80/20 in molar ratio. Line edge roughness is improved by using a resin containing a repeating unit derived from an acrylate derivative and having a specific glass transition point.

  As for content of the repeating unit which has an acid-decomposable group, 20-60 mol% is preferable with respect to all the repeating units, More preferably, it is 25-55 mol%, More preferably, it is 30-50 mol%.

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

  The acid-decomposable resin can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, monomer species are selected from reaction solvents such as ethers such as tetrahydrofuran, 1,4-dioxane, diisopropyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and ester solvents such as ethyl acetate. Further, after dissolving and homogenizing the composition of the present invention such as propylene glycol monomethyl ether acetate described later in a solvent, the reaction vessel is charged and heated as necessary under an inert gas atmosphere such as nitrogen or argon, Polymerization is initiated using a commercially available radical initiator (azo initiator, peroxide, etc.). If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery.

  The concentration of the reaction is 20% by mass or more, preferably 30% by mass or more, and more preferably 40% by mass or more. The reaction temperature is 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 50-100 ° C.

  The repeating structural units represented by the above specific examples may be used singly or in combination.

  The acid-decomposable resin may be used alone or in combination.

  The weight average molecular weight of the acid-decomposable resin is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, as a polystyrene-converted value by the GPC method.

  The dispersity (Mw / Mn) is usually 1 to 10, preferably 1 to 5, more preferably 1 to 4. The smaller the degree of dispersion, the smoother the resolution, resist shape, and resist pattern side walls, and the better the roughness.

  The acid-decomposable resin has the specific repeating unit and has a glass transition temperature of 70 to 150 ° C, preferably 90 to 150 ° C, more preferably 110 to 150 ° C.

  The glass transition temperature (Tg) can be measured by differential scanning calorimeter.

  In order to obtain a resin having the above repeating unit and a glass transition temperature of 70 to 150 ° C., for example, there are the following methods.

  In order to control the glass transition point within the specific range, it is necessary to control not only the repeating unit having the specific alicyclic structure but also the molecular weight and dispersity (Mw / Mn).

  The weight average molecular weight of the acid-decomposable resin is usually 5000 to 30000, preferably 6000 to 25000, and more preferably 7000 to 20000.

  The degree of dispersion of the acid-decomposable resin is usually 3.5 or less, preferably 3.0 or less, more preferably 2.5 or less.

  In order to control the weight average molecular weight and the degree of dispersion, not only the above reaction conditions are selected, but the reaction monomer solution and the radical polymerization initiator solution are dropped into a solvent or the like heated to a constant temperature, or dropped dropwise. A polymerization method is desirable.

  Further, by removing the lower molecular weight side of the resin obtained by polymerization by the fractional reprecipitation method, the effect of the present invention can be further enhanced. The fractional reprecipitation method, for example, removes low molecular weight oligomers with high solvent solubility by pouring the resin solution into the poor solvent of the resin or pouring the poor solvent of the resin into the resin solution. Is the method.

  Examples of the poor solvent for the acid-decomposable resin include hydrocarbon solvents such as n-hexane, n-heptane, and toluene, mixed solvents of hydrocarbon solvents and ester solvents such as ethyl acetate, alcohols such as distilled water, methanol, and ethanol. These may be used alone or as a mixed solvent.

  On the other hand, the above-mentioned reaction solvent and the like can be used as a solvent for dissolving the resin. Here, the low molecular weight oligomer is, for example, one having a weight average molecular weight of 4000 or less.

  In the photosensitive composition of the present invention, the blending amount of the acid-decomposable resin in the entire composition is preferably 40 to 99.99% by mass, more preferably 50 to 99.97% by mass in the total solid content.

[3] (C) Basic compound The photosensitive composition of the present invention preferably contains (C) 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 each independently represent 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. The alkyl group, cycloalkyl group and aryl group as R ²⁵⁰ , R ²⁵¹ and R ²⁵² may have a substituent. As the alkyl group having a substituent, an aminoalkyl group having 1 to 20 carbon atoms and a hydroxyalkyl group having 1 to 20 carbon atoms are preferable. As the cycloalkyl group having a substituent, an aminocycloalkyl group having 3 to 20 carbon atoms and a hydroxycycloalkyl group having 3 to 20 carbon atoms are preferable. These alkyl chains may contain an oxygen atom, a sulfur atom, or a nitrogen atom.

(Wherein R ²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ each independently represents an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 20 carbon atoms).

  Preferred compounds include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted pyrazole, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted or unsubstituted aminomorpholine, substituted or An unsubstituted aminoalkylmorpholine, a substituted or unsubstituted piperidine can be mentioned, and more preferable compounds are imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, trialkylamine structure, aniline structure or pyridine. Examples thereof include a compound having a structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, and an aniline derivative having a hydroxyl group and / or an ether bond.

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

  These basic compounds are used alone or in combination of two or more. The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of solid content of a photosensitive composition, Preferably it is 0.01-5 mass%.

[4] (D) 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 surfactant.

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

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

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

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

[5] (E) 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 (D), 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).

  Such a phenol compound having a molecular weight of 1000 or less can be easily synthesized by those skilled in the art with reference to the methods described in, for example, JP-A-4-1222938, JP-A-2-28531, US Pat. No. 4,916,210, European Patent 219294, and the like. can do.

  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 (D) 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 coated on a substrate (eg, silicon / silicon dioxide coating) used for manufacturing a precision integrated circuit element by an appropriate coating method such as a spinner or a coater, and dried to form a resist film. Form.

Next, actinic rays are irradiated through a predetermined mask, and baking and development are performed. In this way, a good pattern can be obtained. Examples of the actinic ray 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 Specifically, a KrF excimer laser (248 nm), an ArF excimer laser (193 nm), an F ₂ excimer laser (157 nm), an X-ray, an electron beam, etc., and an ArF excimer laser is most preferable. In the present invention, X-rays and electron beams are also included in the actinic rays.

  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.

<Example of resin synthesis>
Synthesis Example 1 (Synthesis of Resin (1-1))
2-norbornyl-2-propyl methacrylate, 3,5-dihydroxy-1-adamantane methacrylate and adamantane lactone acrylate were charged at a ratio of 40/20/40 and dissolved in propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40. 450 g of a solution having a solid content concentration of 22% was prepared. To this solution, 1 mol% of V-601 manufactured by Wako Pure Chemical Industries, Ltd. was added dropwise to 50 g of a mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 heated to 100 ° C. over 6 hours in a nitrogen atmosphere. did. After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration to recover the target resin (1-1). did.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 43/19/38. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 9200, and dispersion degree was 2.1. Moreover, as a result of measuring by the differential scanning calorimeter (DSC), the glass transition point of resin (1-1) was 148 degreeC.

Synthesis Example 2 (Synthesis of Resin (2-1))
Polymerization was carried out in the same manner as in Synthesis Example 1 to obtain the target resin (2-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 38/22/40. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 8330, and dispersion degree was 2.1. Moreover, as a result of performing DSC measurement, the glass transition point of resin (2-1) was 131 degreeC.

Synthesis Example 3 (Synthesis of Resin (3-1))
2-adamantyl-2-propyl methacrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 40/20/40, dissolved in propylene glycol monomethyl ether acetate / 3-methoxy-1-butanol = 60/40, and solid content 450 g of a 22% strength solution was prepared. 8 mol% of Wako Pure Chemical V-601 was added to this solution, and this was heated to 120 ° C. over 6 hours in a nitrogen atmosphere, and a mixed solution of propylene glycol monomethyl ether acetate / 3-methoxy-1-butanol = 60/40 It was dripped at 50g. After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration to recover the target resin (3-1). did.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 36/23/41. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 3270, and dispersion degree was 1.5. Moreover, as a result of performing DSC measurement, the glass transition point of resin (3-1) was 119 degreeC.

Synthesis Example 4 (Synthesis of Resin (3-2))
2-adamantyl-2-propyl methacrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 40/20/40, dissolved in propylene glycol monomethyl ether acetate / 3-methoxy-1-butanol = 60/40, and solid content 450 g of a 22% strength solution was prepared. To this solution was added 6 mol% of V-601 manufactured by Wako Pure Chemical Industries, and this was heated to 120 ° C. over 6 hours in a nitrogen atmosphere, and a mixed solution of propylene glycol monomethyl ether acetate / 3-methoxy-1-butanol = 60/40 It was dripped at 50g. After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration to recover the target resin (3-2). did.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 36/23/41. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 4100, and dispersion degree was 1.6. Moreover, as a result of performing DSC measurement, the glass transition point of resin (3-2) was 139 degreeC.

Synthesis Example 5 (Synthesis of Resin (4-1))
Polymerization was performed in the same manner as in Synthesis Example 1 to obtain the target resin (4-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 37/22/41. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 7760, and dispersion degree was 2.3. Moreover, as a result of performing DSC measurement, the glass transition point of resin (4-1) was 133 degreeC.

Synthesis Example 6 (Synthesis of Resin (4-2))
Resin (4-2) was obtained in the same manner as in Synthesis Example 5 except that the monomer ratio was changed.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 42/21/37. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 7920, and dispersion degree was 2.3. Moreover, as a result of performing DSC measurement, the glass transition point of resin (4-2) was 112 degreeC.

Synthesis Example 7 (Synthesis of Resin (5-1))
Polymerization was performed in the same manner as in Synthesis Example 1 to obtain the target resin (5-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 35/32/33. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 9910, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (5-1) was 122 degreeC.

Synthesis Example 8 (Synthesis of Resin (6-1))
Polymerization was carried out in the same manner as in Synthesis Example 4 to obtain the target resin (6-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 30/22/39/9. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 3890, and dispersion degree was 1.6. Moreover, as a result of performing DSC measurement, the glass transition point of resin (6-1) was 134 degreeC.

Synthesis Example 9 (Synthesis of Resin (7-1))
2-adamantyl-2-propyl methacrylate, 2-adamantyl-2-propyl acrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 20/20/20/40, propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60 / 40 was dissolved to prepare 450 g of a solution having a solid content concentration of 22%. 9 mol% of Wako Pure Chemical V-601 was added to this solution, and this was added dropwise to 50 g of a mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 heated to 80 ° C. over 6 hours in a nitrogen atmosphere. did. After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration to recover the target resin (7-1). did.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 20/20/21/39. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 7980, and dispersion degree was 2.3. Moreover, as a result of performing DSC measurement, the glass transition point of resin (7-1) was 145 degreeC.

Synthesis Example 10 (Synthesis of Resin (7-2))
2-adamantyl-2-propyl methacrylate, 2-adamantyl-2-propyl acrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 20/20/20/40, propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60 / 40 was dissolved to prepare 450 g of a solution having a solid content concentration of 22%. To this solution, 5 mol% of V-601 manufactured by Wako Pure Chemical Industries, Ltd. was added dropwise to 50 g of a mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 heated at 80 ° C. over 6 hours in a nitrogen atmosphere. did. After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration to recover the target resin (7-2). did.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 20/20/21/39. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 9370, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (7-2) was 148 degreeC.

Synthesis Example 11 (Synthesis of Resin (7-3))
Resin (synthetic example 9) except that 2-adamantyl-2-propyl methacrylate, 2-adamantyl-2-propyl acrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 30/10/20/40 7-3) was obtained.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 31/20/19/40. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 8050, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (7-3) was 115 degreeC.

Synthesis Example 12 (Synthesis of resin (7-4))
Resin (synthetic example 9) except that 2-adamantyl-2-propyl methacrylate, 2-adamantyl-2-propyl acrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 35/5/20/40 7-4) was obtained.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 31/6/19/39. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 7800, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (7-3) was 105 degreeC.

Synthesis Example 13 (Synthesis of Resin (8-1))
Acrylic ester of hydroxytetracyclododecanylcarboxylic acid t-butyl ester, dihydroxyadamantane methacrylate and norbornane lactone acrylate are charged in a ratio of 44/6/50 and dissolved in propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 450 g of a solution having a solid content concentration of 22% was prepared. To this solution was added 2.5 mol% of V-601 manufactured by Wako Pure Chemical Industries, and this was heated to 80 ° C. over 6 hours in a nitrogen atmosphere, and 50 g of a mixed solution of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 It was dripped in. After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1, and the precipitated white powder was collected by filtration to recover the target resin (8-1). did.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 45/7/48. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 10370, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (8-1) was 136 degreeC.

Synthesis Example 14 (Synthesis of Resin (9-1))
Polymerization was carried out in the same manner as in Synthesis Example 1 to obtain the desired resin (9-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 45/27/28. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 10180, and dispersion degree was 2.3. Moreover, as a result of performing DSC measurement, the glass transition point of resin (9-1) was 144 degreeC.

Synthesis Example 15 (Synthesis of Resin (10-1))
Polymerization was performed in the same manner as in Synthesis Example 1 to obtain the target resin (10-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 35/19/5/41. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 7630, and dispersion degree was 2.0. Moreover, as a result of performing DSC measurement, the glass transition point of resin (10-1) was 139 degreeC.

Synthesis Example 16 (Synthesis of Resin (11-1))
Polymerization was carried out in the same manner as in Synthesis Example 1 to obtain the target resin (11-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 37/19/39/5. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 7560, and dispersion degree was 1.9. Moreover, as a result of performing DSC measurement, the glass transition point of resin (11-1) was 139 degreeC.

Synthesis Example 17 (Synthesis of Resin (11-2))
A resin (11-2) was obtained in the same manner as in Synthesis Example 16 except that the monomer ratio was changed.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 38/18/33/11. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 7730, and dispersion degree was 2.0. Moreover, as a result of performing DSC measurement, the glass transition point of resin (11-2) was 101 degreeC.

Synthesis Example 18 (Synthesis of Resin (12-1))
Polymerization was performed in the same manner as in Synthesis Example 1 to obtain the target resin (12-1).

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c / d = 39/16/5/40. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 8670, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (12-1) was 147 degreeC.

Synthesis Example 19 (Synthesis of Comparative Resin (R1))
2-Ethyl-2-adamantyl methacrylate and butyrolactone methacrylate were charged at a ratio of 55/45 and dissolved in methyl ethyl ketone / tetrahydrofuran = 5/5 to prepare 100 mL of a solution having a solid content of 20% by mass. To this solution, 2 mol% of V-65 manufactured by Wako Pure Chemical Industries, Ltd. was added dropwise to 10 mL of methyl ethyl ketone heated to 60 ° C. over 4 hours under a nitrogen atmosphere. After completion of the dropwise addition, the reaction solution was heated for 4 hours, 1 mol% of V-65 was added again, and the mixture was stirred for 4 hours. After completion of the reaction, the reaction solution was cooled to room temperature, and a resin (R1), which was a white powder crystallized and precipitated in 3 L of a mixed solvent of distilled water / isopropyl alcohol = 1/1, was collected.

The polymer composition ratio (molar ratio) determined from C ¹³ NMR was 46/54. Moreover, the weight average molecular weight of standard polystyrene conversion calculated | required by GPC measurement was 10700. As a result of DSC measurement, the glass transition point of the resin was 147 ° C.

Synthesis Example 20 (Synthesis of Comparative Resin (R2))
2-adamantyl-2-propyl methacrylate, 2-adamantyl-2-propyl acrylate, dihydroxyadamantane methacrylate and norbornane lactone acrylate were charged at a ratio of 20/20/20/40, propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60 Thus, 450 g of a solution having a solid content concentration of 22% by mass was prepared. To this solution, 3.5 mol% of V-601 manufactured by Wako Pure Chemical Industries, Ltd. was added, and this was heated to 80 ° C. over 6 hours in a nitrogen atmosphere. Propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 60/40 The solution was added dropwise to 50 g of the mixed solution (mass ratio). After completion of dropping, the reaction solution was stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to room temperature, crystallized in 5 L of a mixed solvent of hexane / ethyl acetate = 9/1 (mass ratio), and the precipitated white powder was collected by filtration to obtain a resin (R2) having the following structure. Obtained.

The polymer composition ratio (molar ratio) determined from C ¹³ NMR was 20/20/20/40 corresponding to the order of the above monomers. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 13100, and dispersion degree was 2.1. As a result of DSC measurement, the glass transition point of the resin was 171 ° C.

Synthesis Example 21 (Synthesis of Comparative Resin (R-3))
A target resin (R-3) was obtained according to the same monomer composition and reaction conditions as in Synthesis Example 1 except that the amount of V-601 manufactured by Wako Pure Chemical Industries, Ltd. was 0.8 mol%.

^The polymer composition ratio (molar ratio) determined from ¹³ CNMR was a / b / c = 42/20/38. Moreover, the standard polystyrene conversion weight average molecular weight calculated | required by GPC measurement was 12400, and dispersion degree was 2.2. Moreover, as a result of performing DSC measurement, the glass transition point of resin (R-3) was 158 degreeC.

Examples 1-18 and Comparative Examples 1-4
<Resist preparation>
The components shown in Tables 2 to 3 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 Tables 2-3.

Hereinafter, the abbreviations in each table are as follows.
PAG-A; triphenylsulfonium nonafluorobutanesulfonate DBN; 1,5-diazabicyclo [4.3.0] non-5-ene TPI; 2,4,5-triphenylimidazole TPSA; triphenylsulfonium acetate HEP; N -Hydroxyethylpiperidine DIA; 2,6-diisopropylaniline DCMA; dicyclohexylmethylamine TPA; tripentylamine TOA; tri-n-octylamine HAP; hydroxyantipyrine TBAH; tetrabutylammonium hydroxide TMEA; tris (methoxyethoxyethyl) amine PEA; N-phenyldiethanolamine W-1; Megafac F176 (manufactured by Dainippon Ink & Chemicals, Inc.) (fluorine-based) W-2; Megafax R08 (Dainippon Ink and Chemicals ( ) 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.)
A1; propylene glycol methyl ether acetate A2; 2-heptanone A3; ethyl ethoxypropionate A4; γ-butyrolactone A5; cyclohexanone B1; propylene glycol methyl ether B2; ethyl lactate LCB; The ratio when a plurality of resins or solvents are used is a mass ratio.

<Resist evaluation>
First, ARC-29A-8 manufactured by Brewer Science Co., Ltd. was applied to a silicon wafer at 78 nm using a spin coater, dried, and then the positive photosensitive composition obtained thereon was applied thereon, at 120 ° C. for 90 seconds. A dry, 200 nm positive resist film was prepared and exposed to an ArF excimer laser (ArF stepper manufactured by ISI having a wavelength of 193 nm and NA = 0.6), and immediately after exposure, heated at 120 ° C. for 90 seconds. Developed with an aqueous 38% by mass tetramethylammonium hydroxide solution and rinsed with distilled water to obtain a resist pattern profile.

  The resist pattern of the silicon wafer thus obtained was observed with an SEM, and the resist was evaluated as follows.

[PEB temperature dependence]
Exposure of the isolated contact hole pattern with a mask size of 180 nm is performed with an exposure amount that reproduces an isolated contact hole with a mask size of 180 nm to 130 nm, and the exposure amount to be reproduced with an isolated contact hole of 130 nm with a mask size of 180 nm at a post-heating temperature of 120 ° C. After the exposure is performed with the optimal exposure amount and then the optimal exposure amount, the post-heating is performed at two temperatures of + 2 ° C. and −2 ° C. (122 ° C., 118 ° C.) with respect to the post-heating temperature. The contact hole patterns were measured and their diameters L ₁ and L ₂ were determined. The PEB temperature dependency was defined as a change in diameter per 1 ° C. PEB temperature change, and was calculated by the following formula.

PEB temperature dependency (nm / ° C.) = | L ₁ −L ₂ | / 4
[Line edge roughness]
The line edge edge roughness is measured by using a length-measuring scanning electron microscope (SEM) to observe an isolated pattern of 120 nm and the distance from the reference line where the edge of the line pattern should be 5 μm in the longitudinal direction. Was measured with a length measurement SEM (Hitachi, Ltd. S-8840) to obtain a standard deviation, and 3σ was calculated. A smaller value indicates better performance.

  From Tables 2 to 3, it is clear that the positive resist compositions of Examples 1 to 18 are excellent in line edge roughness and PED temperature dependency.

  In the above examples, ArF excimer laser light is used as the actinic ray. However, similar results were obtained in the case of exposure with KrF excimer laser light and electron beam.

  Moreover, it is thought that the photosensitive composition of this invention exhibits the same effect also about EUV light.

Claims (4)

(A) a compound that generates an aromatic sulfonic acid or an aliphatic sulfonic acid that is not substituted with a fluorine atom by irradiation with actinic rays and (B) a monocyclic or polycyclic hydrocarbon structure and at least A photosensitivity characterized by containing a resin having a repeating unit derived from one type of acrylate derivative and having a glass transition temperature of 70 to 150 ° C., which increases the solubility in an alkali developer by the action of an acid. Composition. The photosensitive composition according to claim 1, wherein the resin as the component (B) has a repeating unit having a lactone group. (B) Resin of component has a repeating unit represented by the following general formula (I), The photosensitive composition of Claim 1 or 2 characterized by the above-mentioned.

In the general formula (I), 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. A pattern forming method comprising: forming a resist film from the photosensitive composition according to claim 1; and exposing and developing the resist film.