JP2006030232A - Photosensitive composition and method for forming pattern by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive resist composition in which sufficiently preferable sensitivity, contrast, resolving power and line edge roughness by irradiation are achieves with EB (electron beams) or EUV (extreme ultraviolet) rays, and also to provide a method for forming a pattern by using the composition. <P>SOLUTION: The positive resist composition contains: a resin having which is decomposed by an effect of an acid to increase solubility with an alkali developing solution, the resin having a group which is decomposed by an effect of an acid to produce an alkali-soluble group and to produce a leaving group having a specified structure; and a compound which generates an acid by an effect of actinic rays or radiation. The method for forming a pattern is carried out by using the above composition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photosensitive composition suitable for use in an ultramicrolithography process such as the manufacture of VLSI and high-capacity microchips and other photofabrication processes. More specifically, the present invention relates to a positive resist composition capable of forming a high-definition pattern, and in particular, a positive resist that can be suitably used for fine processing of a semiconductor element using an electron beam or EUV light (Extreme Ultraviolet: wavelength of around 13 nm). Relates to the composition.

  Conventionally, in the manufacturing process of semiconductor devices such as IC and LSI, fine processing by lithography using a photoresist composition has been performed. In recent years, with the high integration of integrated circuits, the formation of ultrafine patterns in the submicron region and the quarter micron region has been required. Along with this, there is a tendency to shorten the exposure wavelength from g-line to i-line and further to KrF excimer laser light. Furthermore, at present, in addition to excimer laser light, lithography using electron beams, X-rays, or EUV light is also being developed.

  As a resist suitable for a lithography process using such electron beam, X-ray or EUV light, a chemically amplified resist using an acid catalyst reaction is mainly used from the viewpoint of high sensitivity. Effectively used as a main component is a chemically amplified resist composition comprising a phenolic polymer that is insoluble or sparingly soluble in an alkali developer and soluble in an alkali developer by the action of an acid, and an acid generator. Has been.

Japanese Patent Laid-Open No. 2002-62652 (Patent Document 1) discloses an alkali dissolution rate contrast, sensitivity, resolution, pattern shape, etching resistance, processability, and a positive resist material having polystyrene repeating units and aryl groups in side chains. A resist material containing a polymer compound containing a (meth) acrylate repeating unit having a (meth) acrylate repeating unit having a tertiary alkyl group is disclosed.
JP 2003-233191 A (Patent Document 2) discloses a photoresist composition containing a resin having a photoacid labile unit (acid-decomposable group) containing an arylalkyl group in order to provide a high-resolution relief image. Disclosure.

  However, sufficient characteristics have not been obtained with respect to sensitivity, contrast, resolution, and line edge roughness (LER), particularly when exposure is performed with an electron beam or EUV.

JP 2002-62652 A JP 2003-233191 A

  An object of the present invention is to provide a photosensitive composition having sufficiently good sensitivity, contrast, resolution, and line edge roughness (LER), particularly under electron beam or EUV irradiation.

  As a result of intensive studies, the inventors of the present invention decomposed by the action of an acid to generate an alkali-soluble group and have a group that generates a leaving group having a specific structure. The above object has been achieved by a photosensitive composition containing a resin with increased solubility. The photosensitive composition concerning this invention is the following structure.

(1) (A) It decomposes | disassembles by the effect | action of an acid which has a group which produces | generates the leaving group which has a group represented by the following general formula (A) while it decomposes | disassembles by the effect | action of an acid. A resin with increased solubility in an alkaline developer, and
(B) A photosensitive composition comprising a compound that generates an acid by the action of actinic rays or radiation.

In general formula (A),
R _1a represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aralkyl group, or an aryl group.
X represents a hydrogen atom or an organic group.
n1 represents an integer of 1 to 5.
n2 represents an integer of 0 to 4. However, n1 + n2 = 5.
When there are a plurality of each of R _1a and X, they may be the same or different.

(2) A group that decomposes by the action of an acid to generate an alkali-soluble group and a leaving group having a group represented by the general formula (A) is selected from the following general formulas (Z1) to (Z5) The photosensitive composition as described in (1) above, which is any one of the groups described above.

In general formulas (Z1) to (Z5),
R _{11a to} R _13a each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group are each selected from —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, and —SO— on the way. May have at least one of them.
R _14a and R _15a each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group are each selected from —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, and —SO— on the way. May have at least one of them.
R _16a represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group each include —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, and —SO— on the way.
You may have at least one chosen from these.
Two of R _11a , R _12a and R _13a , or two of R _14a , R _15a and R _16a may be bonded to form a ring structure. The ring structure has at least one selected from —O—, —S—, —CO ₂ —, —CO—, —SO ₂ — and —SO— in the middle of the ring. Also good.
In addition, any one of R _11a , R _12a , and R _13a , and any one of R _14a , R _15a , and R _16a contains at least one group represented by the above general formula (A).

(3) The photosensitive composition as described in (1) or (2) above, wherein at least one of X in the general formula (A) is a hydrogen atom.

(4) The above (1) to (3), wherein at least one of X in the general formula (A) is a group (acid-decomposable group) that is decomposed by the action of an acid to generate an alkali-soluble group. The photosensitive composition in any one of.

(5) Any of (1) to (4) above, wherein the resin (A) contains at least one repeating unit among the repeating units represented by the following general formulas (I) and (II) The photosensitive composition as described in any one of.

In general formulas (I) and (II),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoro group (preferably having 1 to 4 carbon atoms).
R ₂ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
n is an integer of 0 to 5, m is an integer of 1 to 5, and 1 ≦ n + m ≦ 5.
R _{3 to} R ₅ each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group.
L ₁ represents a single bond or a divalent linking group.
Z represents a group represented by any one of the general formulas (Z1) to (Z5).

(6) Z in the said general formula (I) is group shown by the said general formula (Z2), The photosensitive composition as described in said (5) characterized by the above-mentioned.

(7) Z in said general formula (II) is group shown by the said general formula (Z4), The photosensitive composition as described in said (5) characterized by the above-mentioned.

(8) The resin (A) further contains at least one repeating unit among the repeating units represented by the following general formulas (III) and (IV): (1) to (7) The photosensitive composition in any one.

In general formulas (III) and (IV),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoro group.
R ₂ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
R _{3 to} R ₅ each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group.
X represents a hydrogen atom or an organic group.
X ₁ represents a hydrogen atom or an organic group.
n is an integer of 0 to 5, m is an integer of 0 to 5, and 0 ≦ n + m ≦ 5.

(9) The photosensitive composition as described in any one of (1) to (8) above, further comprising an organic basic compound.

(10) The photosensitive composition as described in any one of (1) to (9) above, further comprising a surfactant.

(11) The photosensitive composition as described in any one of (1) to (10) above, wherein the component (B) contains (B1) a compound capable of generating an organic sulfonic acid by the action of actinic rays or radiation. Sex composition.

(12) The photosensitive composition as described in any one of (1) to (11) above, further comprising (E) a solvent.

(13) The photosensitive composition as described in any one of (1) to (12) above, which contains propylene glycol monomethyl ether acetate as the solvent.

(14) The photosensitive composition as described in (13) above, further containing propylene glycol monomethyl ether as the solvent.

(15) The photosensitive composition as described in any one of (1) to (14) above, which is a composition for exposure with an electron beam or EUV.

(16) A pattern forming method comprising forming a photosensitive film from the photosensitive composition according to any one of (1) to (15), and exposing and developing the photosensitive film.

  The photosensitive composition of the present invention can realize sufficiently good sensitivity, contrast, resolution, and line edge roughness, particularly under electron beam or EUV irradiation, and can form a fine pattern particularly as a positive resist composition. Can do.

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).

  [1] Decomposes by the action of an acid to generate an alkali-soluble group and has a group that generates a leaving group having a group represented by the general formula (A). Resin with increased solubility (A)

  The acid-decomposable resin (A) of the present invention has a group that decomposes by the action of an acid to generate an alkali-soluble group and a leaving group having a group represented by the following general formula (A).

In general formula (A),
R _1a represents a hydrogen atom, a halogen atom (F, Cl, Br, I), an alkyl group, a cycloalkyl group, an aralkyl group, or an aryl group.
X represents a hydrogen atom or an organic group. The organic group may be an acid-decomposable group or a non-acid-decomposable group. When there are a plurality of Xs, each X may be the same or different, and it is preferable that at least one is a hydrogen atom and at least one is an acid-decomposable group.
n1 represents an integer of 1 to 5.
n2 represents an integer of 0 to 4. However, n1 + n2 = 5.

The alkyl group as R _1a is, for example, an alkyl group having 1 to 8 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group, an octyl group. Preference is given to groups.

The cycloalkyl group as R _1a is, for example, a cycloalkyl group having 3 to 15 carbon atoms, and specific examples include a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group.

The aralkyl group as R _1a is preferably an aralkyl group having 6 to 12 carbon atoms, such as benzyl group, phenethyl group, naphthylmethyl group, naphthylethyl group, naphthylmethyl group, and the like.

The aryl group as R _1a is, for example, an aryl group having 6 to 15 carbon atoms, and specific examples include a phenyl group, a tolyl group, a naphthyl group, an anthryl group, and the like.

  The substituents that these groups may have include hydroxyl group, carboxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group) Etc.).

  The organic group as X preferably has 1 to 40 carbon atoms and may be an acid-decomposable group or a non-acid-decomposable group. X is preferably a hydrogen atom.

The non-acid-decomposable group as X is decomposed by a group that is not an acid-decomposable group (a group that decomposes by the action of an acid to generate an alkali-soluble group), that is, an acid generated from a photoacid generator by exposure, The group which does not produce alkali-soluble groups, such as a hydroxyl group and a carboxy group.
Specific examples of the non-acid-decomposable group as X include, for example, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, —OC (═O) Ra, —OC (═O ) ORa, -C (= O) ORa, -C (= O) N (Rb) Ra, -N (Rb) C (= O) Ra, -N (Rb) C (= O) ORa, -N ( Rb) SO ₂ Ra, —SRa, —SO ₂ Ra, —SO ₃ Ra, or —SO ₂ N (Rb) Ra may be mentioned. Here, Ra and Rb each independently represents an alkyl group, a cycloalkyl group, or an aryl group.

The alkyl group as X is, for example, an alkyl group having 1 to 8 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group, and an octyl group. Can be preferably mentioned.
The cycloalkyl group as X is, for example, a cycloalkyl group having 3 to 15 carbon atoms, and specific examples include a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group.
The alkoxy group as X is, for example, the above alkoxy group having 1 to 8 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, and a cyclohexyloxy group. .

  The aryl group as X is, for example, an aryl group having 6 to 15 carbon atoms, and specific examples include a phenyl group, a tolyl group, a naphthyl group, an anthryl group and the like.

  The acyl group as X is, for example, an acyl group having 2 to 8 carbon atoms. Specifically, a formyl group, an acetyl group, a propanoyl group, a butanoyl group, a pivaloyl group, a benzoyl group and the like can be preferably exemplified. .

  The substituents that these groups may have include hydroxyl group, carboxyl group, halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group) Etc.). As for the cyclic structure, examples of the substituent further include an alkyl group (preferably having 1 to 8 carbon atoms).

  The alkyl group, cycloalkyl group or aryl group as Ra and Rb is the same as those exemplified as X.

As the organic group of the acid-decomposable group of X, for example, —C (R _11a ) (R _12a ) (R _13a ), —C (R _14a ) (R _15a ) (OR _16a ), —CO—OC (R _11a ) ( _R12a ) ( _R13a ).
R _{11a to} R _13a each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. R _14a and R _15a each independently represents a hydrogen atom or an alkyl group. R _16a represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. Two of R _11a , R _12a and R _13a , or two of R _14a , R _15a and R _16a may be bonded to form a ring.
Note that a group having an acid-decomposable group can be introduced into X by modification. Thus, X which introduce | transduced the acid-decomposable group is as follows, for example.
-[C ( _R17a ) ( _R18a )] _p- CO-OC ( _R11a ) ( _R12a ) ( _R13a )
R _17a and R _18a each independently represents a hydrogen atom or an alkyl group. p is an integer of 1 to 4.

  The organic group as X preferably has at least one cyclic structure selected from an alicyclic ring and an aromatic ring, and has a structure including an alicyclic structure represented by the following general formulas (pI) to (pV). It is preferably an acid-decomposable group. The alicyclic structure may be a bridged alicyclic structure.

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 that the alicyclic hydrocarbon group may have include an alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group, and more preferably a substituent selected from the group consisting of a methyl group, an ethyl group, a propyl group, and an isopropyl group. To express. Examples of the 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.
The alkyl group, alkoxy group, and alkoxycarbonyl group may further have a substituent. Examples of such a substituent include an alkoxy group having 1 to 4 carbon atoms (methoxy group, ethoxy group, butoxy group). Group), hydroxy group, oxo group, alkylcarbonyl group (preferably 2 to 5 carbon atoms), alkylcarbonyloxy group group (preferably 2 to 5 carbon atoms), alkyloxycarbonyl group group (preferably 2 to 2 carbon atoms). 5), halogen atoms (chlorine atom, bromine atom, fluorine atom, etc.) and the like.

  In the resin (A), an alkali-soluble group is decomposed by the action of an acid, and the presence of a group that generates a leaving group having a group represented by the following general formula (A) causes alkali solubility in the exposed area. And the resolution and line edge roughness are improved.

  In the present invention, the group which decomposes by the action of the acid contained in the resin (A) to produce an alkali-soluble group and the leaving group having the group represented by the general formula (A) is represented by the following general formula (Z1). It is preferably any group selected from (Z5).

In general formulas (Z1) to (Z5),
R _{11a to} R _13a each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group each have —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, —SO— in the middle. It may be.
R _14a and R _15a each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group each have —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, —SO— in the middle. It may be.
R _16a represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group each have —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, —SO— in the middle. It may be.
Two of R _11a , R _12a and R _13a , or two of R _14a , R _15a and R _16a may be bonded to form a ring structure. The ring structure may have —O—, —S—, —CO ₂ —, —CO—, —SO ₂ — or —SO— in the ring.
Moreover, it is preferable that any one of R _11a , R _12a , and R _13a and any one of R _14a , R _15a , and R _16a contain at least one group represented by the above general formula (A).

  In the present invention, the resin (A) preferably contains at least one repeating unit among the repeating units represented by the following general formulas (I) and (II).

In general formulas (I) and (II),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoro group (preferably having 1 to 4 carbon atoms).
R ₂ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
n is an integer of 0 to 5, m is an integer of 1 to 5, and 1 ≦ n + m ≦ 5.
R _{3 to} R ₅ each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group.
L ₁ represents a single bond or a divalent linking group.
Z represents a group represented by any one of the general formulas (Z1) to (Z5).

R ₁ is preferably a hydrogen atom, a methyl group, or a C _m F _{2m + 1} group (m is preferably 1), and particularly preferably a hydrogen atom or a methyl group.

The alkyl group as R ₂ is, for example, an alkyl group having 1 to 8 carbon atoms, specifically, methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, hexyl group, octyl group. Preference is given to groups.
The alkoxy group as R ₂ is, for example, the above alkoxy group having 1 to 8 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, and a cyclohexyloxy group. it can.

The aryl group as R ₂ is, for example, an aryl group having 6 to 15 carbon atoms, and specific examples include a phenyl group, a tolyl group, a naphthyl group, an anthryl group and the like.
The acyl group as R ₂ is, for example, an acyl group having 2 to 8 carbon atoms, and specifically, a formyl group, an acetyl group, a propanoyl group, a butanoyl group, a pivaloyl group, a benzoyl group, and the like are preferably exemplified. it can.
The alkyl group as R _{3 to} R ₅ is preferably an alkyl group having 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, and a propyl group.

  Each of the above groups may have a substituent. Examples of the substituent that may be included include a hydroxyl group, a carboxy group, a cyano group, a halogen atom (for example, a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom), an alkoxy group (preferably having 1 to 4 carbon atoms, for example, Methoxy group, ethoxy group, propoxy group, butoxy group, etc.), acyl group (preferably having 2 to 5 carbon atoms, such as formyl group, acetyl group, etc.), acyloxy group (preferably having 2 to 5 carbon atoms, such as acetoxy group) And aryl groups (preferably having 6 to 14 carbon atoms, for example, a phenyl group).

The divalent linking group as L ₁ is preferably a linear, branched or cyclic alkylene group, arylene group, heteroarylene group, aralkylene group, and —S—, —C (═O) —, —N. (R ₆ ) —, —SO—, —SO ₂ —, —CO ₂ —, —N (R ₆ ) SO ₂ —, or a divalent group obtained by combining two or more of these groups can be given. Here, R ₆ can include a hydrogen atom or an alkyl group (specific examples of the alkyl group include those similar to the above R ₂ ).

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

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

  It is preferable that the resin (A) further contains at least one repeating unit among the repeating units represented by the following general formulas (III) and (IV).

In general formulas (III) and (IV),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoro group.
R ₂ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
R _{3 to} R ₅ each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group.
X represents a hydrogen atom or an organic group.
X ₁ represents a hydrogen atom or an organic group.
n is an integer of 0 to 5, m is an integer of 0 to 5, and 0 ≦ n + m ≦ 5.
When m is 2 to 5, the plurality of X may be the same or different, and when n is 2 to 5, the plurality of R ₂ may be the same or different.

Of more R ₁ and R _2, it is the same as R ₁ and R ₂ in the general formula (I).
Details of R ₃ to R _5, is the same as R ₃ to R ₅ in the general formula (II).
The details of X are the same as X in general formula (A).

The organic group as X ₁ preferably has 1 to 40 carbon atoms and may be an acid-decomposable group or a non-acid-decomposable group.

Examples of the non-acid-decomposable group include the same non-acid-decomposable groups as X in formula (A).
For example, alkyl group, cycloalkyl group, alkenyl group, aryl group, alkyloxy group (excluding -O-tertiary alkyl), acyl group, cycloalkyloxy group, alkenyloxy group, aryloxy group, alkylcarbonyl Examples thereof include an oxy group, an alkylamidomethyloxy group, an alkylamide group, an arylamidomethyl group, and an arylamide group.
The non-acid-decomposable group is preferably an acyl group, an alkylcarbonyloxy group, an alkyloxy group, a cycloalkyloxy group, an aryloxy group, an alkylamidooxy group, or an alkylamido group, more preferably an acyl group or an alkylcarbonyl group. An oxy group, an alkyloxy group, a cycloalkyloxy group, and an aryloxy group;
In the non-acid-decomposable group, the alkyl group is preferably an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, or a t-butyl group. As the alkyl group, those having 3 to 10 carbon atoms such as cyclopropyl group, cyclobutyl group, cyclohexyl group and adamantyl group are preferable, and as the alkenyl group, carbon number such as vinyl group, propenyl group, allyl group and butenyl group. Those having 2 to 4 carbon atoms are preferable, those having 2 to 4 carbon atoms such as vinyl group, propenyl group, allyl group and butenyl group are preferable as alkenyl groups, and phenyl group, xylyl group and toluyl group are preferable as aryl groups. And those having 6 to 14 carbon atoms such as cumenyl group, naphthyl group and anthracenyl group are preferable. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, a hydroxypropoxy group, an n-butoxy group, an isobutoxy group, or a sec-butoxy group.

Examples of the organic group of the acid-decomposable group for X ₁ include the same acid-decomposable groups as X in formula (A).

The organic group as X ₁ preferably has at least one cyclic structure selected from an alicyclic ring and an aromatic ring, and has a structure including an alicyclic structure represented by the above general formulas (pI) to (pV). It is preferably an acid-decomposable group. The alicyclic structure may be a bridged alicyclic structure.

  Specific examples of the repeating unit represented by the general formula (III) are listed below, but the present invention is not limited thereto.

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

  The resin (A) is copolymerized with other polymerizable monomers suitable so that an alkali-soluble group such as a phenolic hydroxyl group or a carboxyl group can be introduced in order to maintain good developability for an alkali developer. In order to improve the film quality, other hydrophobic polymerizable monomers such as alkyl acrylate and alkyl methacrylate may be copolymerized.

  Resin (A) is not limited to the repeating unit represented by the general formula (I) or (II) having an acid-decomposable group, but the repeating unit represented by the general formula (III) or (IV), or other The repeating unit may have an acid-decomposable group.

In addition, examples of the acid-decomposable group that other repeating units may have include, in addition to the acid-decomposable groups that the repeating units represented by formulas (I) to (IV) may have, for example, —C (= O) -X ₀ -R ₀ can be exemplified. As R ₀ , tertiary alkyl groups such as t-butyl group and t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxyethyl group and the like 1-alkoxyethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3-oxocyclohexyl ester Group, 2-methyl-2-adamantyl group, mevalonic lactone residue and the like. X ₀ represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.

  In the resin (A), it is decomposed by the action of an acid to generate an alkali-soluble group and a repeating unit having a group that generates a leaving group having a group represented by the formula (A) (that is, the formula (Z1) to The content of (including a repeating unit having a group represented by (Z5)) is usually 1 to 97 mol%, preferably 3 to 90 mol%, more preferably based on all repeating units constituting the resin (A). Is 5 to 80 mol%.

  The content of the repeating unit represented by the general formula (I) is usually 1 to 97 mol%, preferably 3 to 90 mol%, more preferably 5 to 80, based on all repeating units constituting the resin (A). Mol%.

  The content of the repeating unit represented by the formula (II) is usually from 3 to 95 mol%, preferably from 5 to 90 mol%, more preferably from 7 to 85 mol%, based on all repeating units constituting the resin (A). %.

  The content of the repeating unit represented by the formula (III) is usually 1 to 90 mol%, preferably 3 to 80 mol%, more preferably 5 to 70 mol%, based on all repeating units constituting the resin (A). %.

  The content of the repeating unit represented by the formula (IV) is usually 1 to 90 mol%, preferably 3 to 80 mol%, more preferably 5 to 70 mol%, based on all repeating units constituting the resin (A). %.

  The content of the repeating unit having an acid-decomposable group is generally from 2 to 97 mol%, preferably from 4 to 97%, based on all repeating units constituting the resin (A), in all repeating units constituting the resin. 90 mol%, particularly preferably 6 to 85 mol%.

  The synthesis of the resin (A) is a precursor of a group that can be decomposed with an acid into an alkali-soluble resin, as described in European Patent No. 254853, JP-A-2-258500, 3-223860, and 4-251259. It can be synthesized by a known synthesis method such as a method of reacting the above, or a method of copolymerizing a monomer having a group decomposable with an acid with various monomers.

The weight average molecular weight (Mw) of the resin (A) is preferably 1,000 or more from the viewpoint of maintaining the film thickness of the unexposed area, and preferably 200,000 or less for increasing the dissolution rate with respect to alkali. More preferably, it is the range of 1,500-100,000, Most preferably, it is the range of 2,000-50,000. Moreover, it is preferable that molecular weight dispersion degree (Mw / Mn) is 1.0-4.0, More preferably, it is 1.0-3.0, Most preferably, it is 1.0-2.5.
Here, the weight average molecular weight is defined by a polystyrene conversion value of gel permeation chromatography.
Moreover, you may use resin (A) in combination of 2 or more types.

  The total amount of the resin (A) added is generally 10 to 96% by mass, preferably 15 to 96% by mass, particularly preferably 20 to 95%, based on the total solid content of the photosensitive composition. % By mass.

[2] Compound (B) that generates acid upon irradiation with actinic rays or radiation
In the present invention, as a compound that generates an acid upon irradiation with actinic rays or radiation (acid generator), a photoinitiator for photocationic polymerization, a photoinitiator for photoradical polymerization, a photodecolorant for dyes, known to occur photochromic agent, or far ultraviolet rays that are used in micro-resists and the like (KrF, ArF excimer laser, etc.), F ₂ excimer laser, electron beam, EUV, an acid by the action of actinic rays or radiation such as X-ray These compounds and mixtures thereof can be appropriately selected and used in combination. Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, o-nitrobenzyl sulfonates, and the like.

  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.

  The content of the acid generator is usually 0.001 to 40% by mass, preferably 0.01 to 20% by mass, particularly preferably 0.1 to 10% by mass, based on the total solid content of the photosensitive composition. is there. One type of acid generator may be used, or two or more types may be mixed and used.

In the present invention, the compound (B1) (sulfonic acid generator) that generates sulfonic acid upon irradiation with actinic rays or radiation is preferable from the viewpoint of improving image performance such as resolution and pattern shape.
Preferred sulfonic acid generators include sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, and disulfones.
Among these, examples of particularly preferable ones are listed below.

  In addition, the combination of (B1) a compound that generates sulfonic acid upon irradiation with actinic rays or radiation (sulfonic acid generator) and (B2) a compound that generates carboxylic acid upon irradiation with actinic rays or radiation (carboxylic acid generator). , Contrast and line edge roughness are improved.

  The sulfonic acid generator / carboxylic acid generator (mass ratio) is usually 1/1 to 100/1, preferably 1/1 to 10/1. By using an acid generator in combination, outgassing and development defects after exposure are further reduced.

  As the carboxylic acid generator, a compound (B2) represented by the following general formula (BII) is particularly preferable.

In formula (BII), R _{21 to} R ₂₃ each independently represents an alkyl group, an alkenyl group or an aryl group, R ₂₄ represents a hydrogen atom, an alkyl group, an alkenyl group or an aryl group, and Z represents a sulfur atom or Represents an iodine atom. When Z is a sulfur atom, p is 1, and when Z is an iodine atom, p is 0.

In the general formula (BII), R _{21 to} R ₂₃ each independently represents an alkyl group, an alkenyl group, or an aryl group, and these groups optionally have a substituent.
The alkyl group, alkenyl group or aryl group as R _{21 to} R ₂₃ may have a substituent, and examples of the substituent for the alkyl group and alkenyl group include a halogen atom (chlorine atom, bromine atom, fluorine atom). Atoms, etc.), aryl groups (phenyl group, naphthyl group etc.), hydroxy groups, alkoxy groups (methoxy group, ethoxy group, butoxy group etc.) and the like. Examples of the substituent of the aryl group include a halogen atom (chlorine atom, bromine atom, fluorine atom, etc.), nitro group, cyano group, alkyl group (methyl group, ethyl group, t-butyl group, t-amyl group). Octyl group, etc.), hydroxy group, alkoxy group (methoxy group, ethoxy group, butoxy group, etc.) and the like.
R _{21 to} R ₂₃ each independently preferably represents an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an aryl group having 6 to 24 carbon atoms, and more preferably 1 carbon atom. An alkyl group having 6 to 6 carbon atoms and an aryl group having 6 to 18 carbon atoms, particularly preferably an aryl group having 6 to 15 carbon atoms. Each of these groups may have a substituent.

R ₂₄ represents a hydrogen atom, an alkyl group, an alkenyl group, or an aryl group.
The alkyl group, alkenyl group, and aryl group as R ₂₄ may have a substituent, and examples of the substituent of the alkyl group and alkenyl group include examples of the substituent when R ₂₁ is an alkyl group. The same as those mentioned above. Examples of the substituent for the aryl group, the R ₂₁ may be the same as those mentioned as examples of the substituent when it is an aryl group.

R ₂₄ is preferably a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an aryl group having 6 to 24 carbon atoms, and more preferably an alkyl group having 1 to 18 carbon atoms. And an aryl group having 6 to 18 carbon atoms, particularly preferably an alkyl group having 1 to 12 carbon atoms and an aryl group having 6 to 15 carbon atoms.

Z represents a sulfur atom or an iodine atom. p is 1 when Z is a sulfur atom, and 0 when Z is an iodine atom.
Two or more cation moieties of formula (BII) are bonded by a single bond or a linking group (for example, -S-, -O-, etc.) to form a cation structure having a plurality of cation moieties of formula (BII). May be.

  Specific examples of the compound (B2) that generates a carboxylic acid upon irradiation with an actinic ray or radiation are given below, but the invention is of course not limited thereto.

[3] Nitrogen-containing basic compound (C)
In the present invention, it is preferable to use a nitrogen-containing basic compound from the viewpoints of improving performance such as resolution and improving storage stability.
A preferable nitrogen-containing basic compound that can be used in the present invention is a compound having a stronger basicity than phenol.
As a preferable chemical environment, the following general formulas (A) to (E) can be exemplified. Formulas (B) to (E) may be part of a ring structure.

Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, Here, 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.
Moreover, these may contain an oxygen atom, a sulfur atom, and 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.
Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms of different chemical environments in one molecule, and particularly preferred are compounds containing both an amino group and a ring structure containing a nitrogen atom, or alkylamino A compound having a group.

  Preferred examples include guanidine, aminopyridine, aminoalkylpyridine, aminopyrrolidine, indazole, imidazole, pyrazole, pyrazine, pyrimidine, purine, imidazoline, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine and the like. These compounds may have a substituent, and preferred substituents include an amino group, an aminoalkyl group, an alkylamino group, an aminoaryl group, an arylamino group, an alkyl group, an alkoxy group, an acyl group, an acyloxy group, An aryl group, an aryloxy group, a nitro group, a hydroxyl group, a cyano group, etc. are mentioned.

  Particularly preferred compounds include guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, imidazole, 2-methylimidazole, 4-methylimidazole, N-methylimidazole, 2-phenylimidazole, 4, 5-diphenylimidazole, 2,4,5-triphenylimidazole, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- ( Aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, 4-amino Ethylpyridine,

3-aminopyrrolidine, piperazine, N- (2-aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-aminoethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl)- Examples include 5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N- (2-aminoethyl) morpholine. It is not limited to this.

A tetraalkylammonium salt type nitrogen-containing basic compound can also be used.
Among these, tetraalkylammonium hydroxide having 1 to 8 carbon atoms (tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra- (n-butyl) ammonium hydroxide, etc.) is particularly preferable.
These nitrogen-containing basic compounds are used alone or in combination of two or more.

  The use ratio of the acid generator and the nitrogen-containing basic compound in the composition is such that (total amount of acid generator) / (nitrogen-containing basic compound) (molar ratio) is 2.5 or more in terms of sensitivity and resolving power. Preferably, it is preferably 300 or less from the viewpoint of the resist pattern and resolution over time until the heat treatment after exposure. (Acid generator) / (nitrogen-containing basic compound) (molar ratio) is more preferably 5.0 to 200, still more preferably 7.0 to 150.

[4] Surfactants In the present invention, surfactants can be used, which are preferable from the viewpoints of film forming properties, pattern adhesion, development defect reduction, and the like.

  Specific examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene Polyoxyethylene alkyl allyl ethers such as nonylphenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Sorbitan fatty acid esters such as rate, polyoxyethylene sorbitan monolaurate, polyoxyethylene Sorbitan mono palmitate - door,

Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, EFTOP EF301, EF303, EF352 (Shin-Akita Kasei) (Made by Co., Ltd.), MegaFuck F171, F173 (Dainippon Ink and Chemicals), Florad FC430, FC431 (Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102 , SC103, SC04, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), Troysol S-366 (manufactured by Troy Chemical Co., Ltd.), silicon surfactants, organosiloxane polymer KP341 ( Yue Chemical Industries, Ltd.) and acrylic or methacrylic acid-based (co) polymer Polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Chemical Co., Ltd.). The compounding amount of these surfactants is usually 2 parts by mass or less, preferably 1 part by mass or less per 100 parts by mass of the solid content in the composition of the present invention.
These surfactants may be added alone or in some combination.

The surfactant is any one of fluorine and / or silicon surfactants (fluorine surfactants and silicon surfactants, surfactants containing both fluorine atoms and silicon atoms), or It is preferable to contain 2 or more types.
As these surfactants, for example, JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, JP-A-62-170950, JP-A-63-34540 No. 7, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, JP-A 2002-277862, US Pat. No. 5,405,720. , No. 5,360,692, No. 5,529,881, No. 5,296,330, No. 5,543,098, No. 5,576,143, No. 5,294,511, No. 5,824,451. The following commercially available surfactants can also be used as they are.
Examples of commercially available surfactants that can be used include 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, surfactants are derived from fluoroaliphatic compounds produced by the telomerization method (also referred to as the telomer method) or the oligomerization method (also referred to as the oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). It may be a unit having different chain lengths in the same chain length, such as a block linked body) or a poly (block linked body of oxyethylene and oxypropylene) group. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).
Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy) Copolymer) of (ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate), 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 the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total amount of the photosensitive composition (excluding the solvent).

[5] Other components The photosensitive composition of the present invention may further contain a dye, a photobase generator and the like, if necessary.

1. Dye A dye can be used in the present invention.
Suitable dyes include oily dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-505 (oriental chemical industry) (Corporation), crystal violet (CI42555), methyl violet (CI42535), rhodamine B (CI45170B), malachite green (CI42000), methylene blue (CI522015), and the like.

2. Photobase generator As photobase generators that can be added to the composition of the present invention, JP-A-4-151156, JP-A-4-162040, JP-A-5-197148, JP-A-5-5995, JP-A-6-194835, Examples thereof include compounds described in JP-A-8-146608, JP-A-10-83079 and European Patent No. 622682, specifically, 2-nitrobenzylcarbamate, 2,5-dinitrobenzylcyclohexylcarbamate, N-cyclohexyl-4- Methylphenylsulfonamide, 1,1-dimethyl-2-phenylethyl-N-isopropylcarbamate and the like can be suitably used. These photobase generators are added for the purpose of improving the resist shape and the like.

3. Solvents The photosensitive composition of the present invention is dissolved in a solvent that dissolves each of the above components and coated on a support. The total solid concentration in the photosensitive composition is usually preferably 2 to 30% by mass, more preferably 3 to 25% by mass.
Solvents used here include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethyl Formamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable. Or mixed to use.

  The photosensitive composition of the present invention is applied on a substrate to form a thin film. The thickness of this coating film is preferably 0.05 to 4.0 μm.

  In the present invention, a commercially available inorganic or organic antireflection film can be used if necessary. Furthermore, an antireflection film can be applied to the lower layer of the photosensitive film formed from the photosensitive composition.

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

  In addition, as the organic antireflection film, commercially available organic antireflection films such as DUV30 series, DUV-40 series manufactured by Brewer Science, AR-2, AR-3, AR-5 manufactured by Shipley, etc. may be used. it can.

In the manufacture of precision integrated circuit elements, the pattern formation process on the photosensitive film is performed on the substrate (eg, silicon / silicon dioxide coated substrate, glass substrate, ITO substrate, quartz / chromium oxide coated substrate, etc.). A photosensitive composition is applied, dried or baked to form a photosensitive film, and then a deep ultraviolet ray (KrF, ArF excimer laser, etc.), F ₂ excimer laser, electron beam, EUV, X A good pattern can be formed by irradiation with actinic rays such as rays or radiation, and preferably by heating, developing, rinsing and drying.
In addition, the photosensitive composition of this invention has preferable exposure by an electron beam or EUV.

Examples of the alkaline developer used in development include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, and primary amines such as ethylamine and n-propylamine. Diethylamine, di-n
-Secondary amines such as butylamine; tertiary amines such as triethylamine and methyldiethylamine; alcohol amines such as dimethylethanolamine and triethanolamine; and fourth amines such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and choline. An aqueous solution (usually 0.1 to 20% by mass) of an alkali such as a quaternary ammonium salt, a cyclic amine such as pyrrole or piperidine, or the like can be used. Furthermore, an appropriate amount of an alcohol such as isopropyl alcohol or a nonionic surfactant may be added to the alkaline aqueous solution.
Among these developers, quaternary ammonium salts are preferable, and tetramethylammonium hydroxide and choline are more preferable.

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 further in detail, the content of this invention is not limited by this.

[Resin synthesis]
Synthesis Example 1: Synthesis of Intermediate 1

  Hydroquinone 55.1 g and chloroethyl vinyl ether 106.6 g were dissolved in DMAc 1.5 L, sodium hydroxide 48 g was added, and the mixture was stirred at 100 ° C. for 2 hours. Thereafter, the NaCl salt was filtered, 700 ml of ethyl acetate was added, water was further added, and washing and liquid separation operations were performed twice. 30 g of magnesium sulfate was added to the organic layer for dehydration, magnesium sulfate filtration was performed, and the solvent was distilled off under reduced pressure, followed by purification by silica gel column chromatography to obtain 77.5 g of Intermediate 1.

  Synthesis Example 2: Synthesis of vinyl ether 1

  72.1 g of Intermediate 1 obtained in Synthesis Example 1 and 4.9 g of 4-dimethylaminopyridine were dissolved in 60 g of pyridine and stirred at room temperature. Thereafter, 77.4 g of acetic anhydride was added dropwise over 1 hour. After dropping, the mixture was heated to 90 ° C. and further stirred for 4 hours, neutralized with 1N HCl aqueous solution, washed with ethyl acetate-water, and extracted. The organic layer was dehydrated using 40 g of anhydrous sodium sulfate, and after distilling off the solvent, 78.2 g of vinyl ether 1 was obtained.

  Synthesis Example 3: Synthesis of Polymer 1

  In a reaction vessel, 20 g of VP-8000 (manufactured by Nippon Soda Co., Ltd.) was dissolved in 100 g of PGMEA, and this solution was depressurized to 60 ° C. and 20 mmHg, and about 20 g of the solvent was distilled off together with water remaining in the system. The mixture was cooled to 20 ° C., 40.69 g of vinyl ether 14 obtained in Synthesis Example 2 and 1.0 g of p-toluenesulfonic acid were added, and the mixture was stirred at room temperature for 2 hours. Thereafter, 1.16 g of triethylamine was added for neutralization. This solution was dropped into 1 L of hexane to precipitate a polymer. The filtered solid was dissolved in 150 ml of acetone, dropped again into 1 L of hexane, the filtered solid was added to the reaction vessel, 120 ml of tetrahydrofuran, 20 ml of water and 7.3 g of tetramethylammonium hydroxide were added, and the mixture was heated to reflux for 4 hours. . Thereafter, the reaction solution was allowed to cool to room temperature, neutralized by adding a 0.1N hydrochloric acid aqueous solution, and the reaction solution was dropped into 2 L of water. The precipitated polymer was dissolved in acetone, dropped again into 1 L of water, and the precipitated solid was separated by filtration and dried under reduced pressure to obtain 48.0 g of polymer 1.

Synthesis Example 4: Synthesis of polymer A-1

  In a reaction vessel, 20 g of the polymer 1 obtained in Synthesis Example 3 was dissolved in 100 g of PGMEA, this solution was decompressed to 60 mm and 20 mmHg, and about 20 g of the solvent was distilled off together with the remaining water in the system. The mixture was cooled to 20 ° C., 2.7 g of 2-phenoxyethyl vinyl ether and 0.04 g of pyridinium p-toluenesulfonate were added, and the mixture was stirred at room temperature for 3 hours. Thereafter, 0.03 g of triethylamine was added for neutralization, and 40 g of ethyl acetate and 40 g of water were added for washing operation three times. Thereafter, the amount of the solvent was adjusted to obtain a 30% by mass polymer solution. This polymer is designated as A-1. From 1H and 13C-NMR analyses, polymer A-1 was a polymer having an acetal protection rate of OH in polymer 1 of 24.3%.

  Synthesis Example 5: Synthesis of Intermediate 2

  In a reaction vessel, 166.2 g of (4-hydroxyphenyl) acetic acid methyl ester and 500 ml of dehydrated tetrahydrofuran were added, nitrogen gas was passed through the system while stirring, and the solution was cooled in an ice bath. Thereto, 2.2 L of methylmagnesium bromide (concentration 1.0 M tetrahydrofuran solution) was added dropwise over 3 hours. After dropping, the temperature was gradually raised to room temperature, and the mixture was further stirred for 1 hour. Thereafter, a saturated aqueous ammonium chloride solution was added for neutralization, and the mixture was extracted with ethyl acetate-water. The organic layer was dehydrated using 40 g of anhydrous sodium sulfate, the solvent was distilled off, and the residue was purified by silica gel column chromatography to obtain 144.6 g of Intermediate 2.

  Synthesis Example 6: Synthesis of Monomer 1

  In the reaction vessel, 116.4 g of the intermediate 2 obtained in Synthesis Example 5, 1000 ml of dehydrated tetrahydrofuran and 60.9 g of pyridine were added, nitrogen gas was allowed to flow through the system while stirring, and the solution was cooled in an ice bath. Thereto was added dropwise a solution of 69.7 g of acrylic acid chloride in 100 ml of tetrahydrofuran over 1 hour. After the dropwise addition, the temperature was gradually raised to room temperature, and the mixture was further stirred for 2 hours. Thereafter, a saturated aqueous sodium hydrogen carbonate solution was added, and the mixture was extracted with ethyl acetate-water. The organic layer was dehydrated with 25 g of anhydrous sodium sulfate, the solvent was distilled off, and the residue was purified by silica gel column chromatography to obtain 103.3 g of monomer 1.

  Synthesis Example 7: Synthesis of polymer 2

  In a reaction vessel, 66.1 g of monomer 1 obtained in Synthesis Example 6 was dissolved in 120 ml of tetrahydrofuran, and nitrogen gas was allowed to flow through the system while stirring. The polymerization initiator V-601 (made by Wako Pure Chemical Industries Ltd.) 4.8g was added there, and the reaction solution was heated at 65 degreeC. After 10 hours of heating and stirring, the reaction solution was allowed to cool to room temperature and dropped into 1.5 L of hexane to precipitate a polymer. The filtered solid was dissolved in 150 ml of acetone, dropped again into 2 L of hexane, and the filtered solid was dried under reduced pressure to obtain 48.9 g of polymer 2. From the GPC analysis, the polymer 2 had a weight average molecular weight of 10,500 and a molecular weight dispersity of 1.59.

  Synthesis Example 8: Synthesis of polymer A-7

  In a reaction vessel, 20 g of the polymer 2 obtained in Synthesis Example 7 was dissolved in 100 g of PGMEA, this solution was decompressed to 60 mm and 20 mmHg, and about 20 g of the solvent was distilled off together with water remaining in the system. The mixture was cooled to 20 ° C., 4.7 g of 2-cyclohexylethanol, 3.6 g of t-butyl vinyl ether, and 0.06 g of pyridinium p-toluenesulfonate were added and stirred at room temperature for 1 hour. Thereafter, 0.05 g of triethylamine was added for neutralization, and 40 g of ethyl acetate and 40 g of water were added for washing operation three times. Thereafter, the amount of the solvent was adjusted to obtain a 30% by mass polymer solution. This polymer is designated as A-7. From 1H and 13C-NMR analysis of polymer A-7, the acetal protection rate of phenolic OH was 25.6%.

Polymers A-2 to A-6 and A-8 to A-18 were obtained in the same manner except that the monomer, polymer and vinyl ether used were changed.
The structures of the polymers A-1 to A-18 are shown below.

  Table 1 shows the weight average molecular weight, molecular weight dispersity, and composition ratio of the synthesized polymer.

[Examples 1 to 18 and Comparative Example 1]
(Preparation of photosensitive composition)
Resin of the present invention shown in Table 2: 0.948 g (in terms of solid content)
Acid generator: 0.05g
Organic basic compound: 0.003 g
Surfactant: 0.002g
Was dissolved in 16.79 g of the solvent shown in Table 2 below to prepare a solution having a solid content concentration of 5.0% by mass. This solution was filtered through a polytetrafluoroethylene filter having a pore size of 0.1 μm to obtain a photosensitive composition (positive resist solution). In the composition for the comparative example, a resin other than the present invention (Comparative Resin 1) was used.

[Pattern preparation and evaluation (electron beam)]
The positive resist solution prepared as described above is uniformly applied on a silicon wafer subjected to hexamethyldisilazane treatment by using a spin coater, and is heated and dried at 120 ° C. for 90 seconds to obtain a photosensitive film having a film thickness of 0.3 μm. A characteristic film was formed. The photosensitive film was irradiated with an electron beam using an electron beam drawing apparatus (HL750 manufactured by Hitachi, Ltd., acceleration voltage 50 KeV). After irradiation, it was baked at 110 ° C. for 90 seconds, immersed in an aqueous 2.38 mass% tetramethylammonium hydroxide (TMAH) solution for 60 seconds, rinsed with water for 30 seconds and dried. The obtained pattern was evaluated by the following method.

〔sensitivity〕
The cross-sectional shape of the obtained pattern was observed using a scanning electron microscope (S-4300, manufactured by Hitachi, Ltd.). The minimum irradiation energy when resolving a 150 nm line (line: space = 1: 1) was defined as sensitivity.

[Resolution]
The resolving power was defined as the limiting resolving power (line and space were separated and resolving) at the irradiation dose showing the above sensitivity.

[Line edge roughness]
The distance from the reference line where there should be an edge using a scanning electron microscope (S-9220, manufactured by Hitachi, Ltd.) at any 30 points in the length direction of 50 μm of the 150 nm line pattern at the irradiation dose showing the sensitivity described above. Was measured, the standard deviation was obtained, and 3σ was calculated.

  The evaluation results are shown in Table 2.

  The symbols in Table 2 are as follows.

  [Acid generator]

[Surfactant]
D-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.)
D-2: Megafuck R08 (manufactured by Dainippon Ink & Chemicals, Inc.)
D-3: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)
D-4: Polyoxyethylene lauryl ether

〔solvent〕
S-1: Propylene glycol monomethyl ether acetate S-2: Propylene glycol monomethyl ether

[Basic compounds]
N-1: Trioctylamine N-2: 1,5-diazabicyclo [4.3.0] -5-nonene N-3: 2,4,6-triphenylimidazole

Comparative resin 1: weight average molecular weight 8900, molecular weight dispersity 1.54,
Composition ratio (molar ratio) 70/10/20

  From the results in Table 2, it can be seen that the photosensitive composition of the present invention has a high resolution and excellent line edge roughness as compared with the composition of the comparative example with respect to pattern formation by electron beam irradiation.

[Examples 19 to 25 and Comparative Example 2]
[Pattern preparation and evaluation (EUV)]
Using the photosensitive compositions of Examples 1, 3, 4, 6, 7, 15, 18 and Comparative Example 1,
A photosensitive film was obtained in the same manner as in Example 1. However, the photosensitive film thickness was 0.15 μm. The obtained photosensitive film was subjected to surface exposure using EUV light (wavelength 13 nm) while changing the exposure amount in 0.5 mJ increments within the range of 0 to 10.0 mJ, and further baked at 110 ° C. for 90 seconds. Then, 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. These results are shown in Table 3 as Examples 19 to 25 and Comparative Example 2, respectively.

  From the results in Table 3, it can be seen that the photosensitive composition of the present invention is superior in sensitivity and high contrast as compared with the composition of the comparative example in the property evaluation by irradiation with EUV light.

Claims (6)

(A) It decomposes | disassembles by the effect | action of an acid, and has an alkali-soluble group, It has a group which produces | generates the leaving group which has a group represented by the following general formula (A), It decomposes | disassembles by the effect | action of an acid, and an alkali developing solution A resin with increased solubility in and
(B) A photosensitive composition comprising a compound that generates an acid by the action of actinic rays or radiation.
In general formula (A),
R _1a represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aralkyl group, or an aryl group.
X represents a hydrogen atom or an organic group.
n1 represents an integer of 1 to 5.
n2 represents an integer of 0 to 4. However, n1 + n2 = 5.
When there are a plurality of each of R _1a and X, they may be the same or different. Any group selected from the following general formulas (Z1) to (Z5) is selected from the following general formulas (Z1) to (Z5), which decomposes by the action of an acid to generate an alkali-soluble group and a leaving group having a group represented by the general formula (A). The photosensitive composition according to claim 1, wherein the photosensitive composition is any one of these groups.
In general formulas (Z1) to (Z5),
R _{11a to} R _13a each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group each have —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, or —SO— in the middle. You may do it.
R _14a and R _15a each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group are each selected from —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, and —SO— on the way. May have at least one of them.
R _16a represents an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group or an aryl group. The alkyl group, the cycloalkyl group, the alkenyl group, and the aralkyl group are each selected from —O—, —S—, —CO ₂ —, —CO—, —SO ₂ —, and —SO— on the way. May have at least one of them.
Two of R _11a , R _12a and R _13a , or two of R _14a , R _15a and R _16a may be bonded to form a ring structure. The ring structure has at least one selected from —O—, —S—, —CO ₂ —, —CO—, —SO ₂ — and —SO— in the middle of the ring. Also good.
In addition, any one of R _11a , R _12a , and R _13a , and any one of R _14a , R _15a , and R _16a contains at least one group represented by the above general formula (A).   3. The photosensitive composition according to claim 1, wherein at least one of X in the general formula (A) is a hydrogen atom.   The photosensitive composition according to claim 1, wherein at least one of X in the general formula (A) is a group that decomposes by the action of an acid to generate an alkali-soluble group. The photosensitive composition according to any one of claims 1 to 4, wherein the resin (A) contains at least one repeating unit among the repeating units represented by the following general formulas (I) and (II). object.
In general formulas (I) and (II),
R ₁ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoro group.
R ₂ represents an alkyl group, a halogen atom, an aryl group, an alkoxy group or an acyl group.
n is an integer of 0 to 5, m is an integer of 1 to 5, and 1 ≦ n + m ≦ 5.
R _{3 to} R ₅ each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group.
L ₁ represents a single bond or a divalent linking group.
Z represents a group represented by any one of the general formulas (Z1) to (Z5).   A pattern forming method comprising: forming a photosensitive film from the photosensitive composition according to claim 1, and exposing and developing the photosensitive film.