JP6088843B2 - Pattern formation method - Google Patents

Description

  The present invention relates to a base agent and a pattern forming method.

  In recent years, with the further miniaturization of large-scale integrated circuits (LSIs), a technique for processing more delicate structures is required. In response to such a demand, attempts have been made to form a finer pattern using a phase separation structure formed by self-assembly of block copolymers in which incompatible blocks are bonded to each other.

  In order to utilize the phase separation of the block copolymer, it is essential to form the self-assembled nanostructure formed by the microphase separation only in a specific region and arrange it in a desired direction. In order to realize these position control and orientation control, methods such as graphoepitaxy for controlling the phase separation pattern by the guide pattern and chemical epitaxy for controlling the phase separation pattern by the difference in the chemical state of the substrate have been proposed. (For example, refer nonpatent literature 1).

  As one of the methods for satisfactorily phase-separating the block copolymer and forming a fine pattern, a neutral layer having a surface free energy intermediate between the surface free energies of the two block chains is formed on the substrate. A method is disclosed in which the surface on which the block copolymer on the substrate contacts is in a state where the surface free energy is intermediate between the surface free energies of the two block chains (for example, , See Patent Document 1).

JP 2008-36491 A

Proceedings of SPIE, Volume 7637, 76370G-1 (2010).

  However, in the method described in Patent Document 1, it is necessary to select a neutral layer material having a desired surface free energy according to the type of block copolymer to be used, and to control the surface free energy of the neutral layer. Therefore, there has been a demand for a base material that can provide a good pattern by phase separation of the block copolymer and can be used more easily.

  The present invention has been made in view of the above circumstances, and uses a phase separation of a block copolymer to manufacture a substrate having a nanostructure having a more freely designed position and orientation on the substrate surface. It is an object of the present invention to provide a pattern forming method for a layer containing a base material to be obtained and a block copolymer using the base agent.

A second aspect of the present invention, on a substrate, coated with lower Chizai, forming a layer consisting of lower land agent, then, on a layer consisting of lower land agent, an acid generated upon exposure A step of forming a resist film by applying a resist composition whose solubility in a developer is changed by the action of an acid; a step of exposing the resist film; and a step of developing the resist film to form a resist pattern And forming a layer containing a block copolymer in which a plurality of types of blocks are bonded on the layer made of the base material on which the resist pattern is formed, and then phase-separating the layer containing the block copolymer, and And a step of selectively removing a phase composed of at least one block of a plurality of types of blocks constituting the block copolymer from the layer containing the block copolymer. A Rupa turn-forming method, the underlying agent comprises a resin component having a structural unit derived from an aromatic ring-containing monomer (A '), an acid generator component that generates acid on exposure (B), and the The pattern forming method (hereinafter referred to as “pattern forming method 1” ), which contains 5 to 50 parts by mass of the acid generator component (B) with respect to 100 parts by mass of the resin component (A ′). ).

［式中、Ｒ^２０１〜Ｒ^２０７、およびＲ^２１１〜Ｒ^２１２は、それぞれ独立に下記式（ｃａ−ｒ−１）〜（ｃａ−ｒ−７）のいずれかで表される置換基を有するアリール基、下記式（ｃａ−ｒ−１）〜（ｃａ−ｒ−７）のいずれかで表される置換基を有するアルキル基または下記式（ｃａ−ｒ−１）〜（ｃａ−ｒ−７）のいずれかで表される置換基を有するアルケニル基を表し、Ｒ^２０１〜Ｒ^２０３、Ｒ^２０６〜Ｒ^２０７、Ｒ^２１１〜Ｒ^２１２は、相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｒ^２０８〜Ｒ^２０９はそれぞれ独立に水素原子または炭素数１〜５のアルキル基を表し、Ｒ^２１０は置換基を有していてもよいアリール基、アルキル基、アルケニル基、又は−ＳＯ_２−含有環式基であり、Ｌ^２０１は−Ｃ（＝Ｏ）−または−Ｃ（＝Ｏ）−Ｏ−を表し、Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基またはアルケニレン基を表し、ｘは１または２であり、Ｗ^２０１は（ｘ＋１）価の連結基を表す。］

［式中、Ｒ’^２０１はそれぞれ独立に、水素原子、置換基を有していてもよい環式基、鎖状のアルキル基、または鎖状のアルケニル基である。］

A third aspect of the present invention, on a substrate, coated with lower Chizai, forming a layer consisting of lower land agent, then, on a layer consisting of lower land agents, coupling a plurality of types of polymer forming a layer containing a block copolymer, a step of phase separation of the layer containing the block copolymer, a Rupa turn-forming method having a said underlying agent is constituted from an aromatic ring-containing monomer A resin component (A ′) having a unit and an acid generator component (B), and 5 to 50 parts by mass of the acid generator component (B) with respect to 100 parts by mass of the resin component (A ′). ), And the acid generator component (B) includes an onium salt acid generator having a cation moiety represented by any one of the following general formulas (ca-1) to (ca-4). Pattern formation method (hereinafter referred to as “pattern formation method 2”). To provide some.) It is.

[Wherein R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² are each independently an aryl having a substituent represented by any of the following formulas (ca-r-1) to (ca-r-7): Group, an alkyl group having a substituent represented by any of the following formulas (ca-r-1) to (ca-r-7), or the following formulas (ca-r-1) to (ca-r-7) an alkenyl group having a substituent represented by any one ^{of, R 201 ~R 203, R 206} ~R 207, R 211 ~R 212 is forms a ring with the sulfur atom bonded to each other May be. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ²¹⁰ is an aryl group, alkyl group, alkenyl group, or —SO ₂ — containing an optionally substituted substituent. A cyclic group, L ²⁰¹ represents —C (═O) — or —C (═O) —O—, Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group, and x represents 1 or 2 and W ²⁰¹ represents a (x + 1) -valent linking group. ]

[Wherein, R ′ ²⁰¹ each independently represents a hydrogen atom, an optionally substituted cyclic group, a chain alkyl group, or a chain alkenyl group. ]

In the present specification and claims, “aliphatic” is a relative concept with respect to aromatics, and is defined to mean groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups.
The “alkylene group” includes linear, branched, and cyclic divalent saturated hydrocarbon groups unless otherwise specified. The same applies to the alkyl group in the alkoxy group.
The “halogenated alkyl group” is a group in which part or all of the hydrogen atoms of the alkyl group are substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
“Fluorinated alkyl group” or “fluorinated alkylene group” refers to a group in which part or all of the hydrogen atoms of an alkyl group or alkylene group are substituted with fluorine atoms.
“Structural unit” means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).
“A structural unit derived from an acrylate ester” means a structural unit formed by cleavage of an ethylenic double bond of an acrylate ester.
“Acrylic acid ester” is a compound in which the hydrogen atom at the carboxy group terminal of acrylic acid (CH ₂ ═CH—COOH) is substituted with an organic group.
In the acrylate ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The substituent that replaces the hydrogen atom bonded to the α-position carbon atom is an atom or group other than a hydrogen atom, such as an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, or a hydroxy group. An alkyl group etc. are mentioned. The α-position carbon atom of the acrylate ester is a carbon atom to which a carbonyl group is bonded unless otherwise specified.
Hereinafter, an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylate ester. Further, the acrylate ester and the α-substituted acrylate ester may be collectively referred to as “(α-substituted) acrylate ester”.
“A structural unit derived from hydroxystyrene or a hydroxystyrene derivative” means a structural unit formed by cleavage of an ethylenic double bond of hydroxystyrene or a hydroxystyrene derivative.
“Hydroxystyrene derivative” is a concept including those in which the hydrogen atom at the α-position of hydroxystyrene is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. The derivatives include those in which the hydrogen atom at the α-position may be substituted with a substituent, the hydrogen atom of the hydroxyl group of hydroxystyrene substituted with an organic group, and the hydrogen atom at the α-position substituted with a substituent. Examples include those in which a substituent other than a hydroxyl group is bonded to a good benzene ring of hydroxystyrene. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.
Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include the same substituents as those mentioned as the substituent at the α-position in the α-substituted acrylic ester.
The “structural unit derived from vinyl benzoic acid or a vinyl benzoic acid derivative” means a structural unit configured by cleavage of an ethylenic double bond of vinyl benzoic acid or a vinyl benzoic acid derivative.
The “vinyl benzoic acid derivative” is a concept including a compound in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. These derivatives include those obtained by substituting the hydrogen atom of the carboxy group of vinyl benzoic acid with an organic group, which may be substituted with a hydrogen atom at the α-position, and the hydrogen atom at the α-position with a substituent. Examples thereof include those in which a substituent other than a hydroxyl group and a carboxy group is bonded to the benzene ring of vinyl benzoic acid. The α-position (α-position carbon atom) means a carbon atom to which a benzene ring is bonded unless otherwise specified.
“Styrene” is a concept that includes styrene and those in which the α-position hydrogen atom of styrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group.
“Structural unit derived from styrene” and “structural unit derived from styrene derivative” mean a structural unit formed by cleavage of an ethylenic double bond of styrene or a styrene derivative.
The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.
Specific examples of the halogenated alkyl group as the substituent at the α-position include groups in which part or all of the hydrogen atoms of the above-mentioned “alkyl group as the substituent at the α-position” are substituted with a halogen atom. It is done. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
Specific examples of the hydroxyalkyl group as a substituent at the α-position include a group in which part or all of the hydrogen atoms of the “alkyl group as the substituent at the α-position” are substituted with a hydroxyl group. 1-5 are preferable and, as for the number of the hydroxyl groups in this hydroxyalkyl group, 1 is the most preferable.
“Exposure” is a concept including general irradiation of radiation.

  According to the present invention, by using phase separation of a block copolymer, a base material capable of producing a substrate provided with a nanostructure whose position and orientation are more freely designed on the surface of the substrate, and the base material are used. It is possible to provide a method for patterning a layer containing a block copolymer.

It is a schematic process drawing explaining the example of an embodiment of pattern formation method 1 of the present invention. It is a schematic process drawing explaining the example of an embodiment of pattern formation method 2 of the present invention.

≪Base material≫
The base agent of the present invention is a base agent used for phase-separating a layer containing a block copolymer in which a plurality of types of blocks formed on a substrate are bonded, and has a structural unit derived from an aromatic ring-containing monomer. It includes a resin component (A ′) and an acid generator component (B) that generates an acid upon exposure.
The base agent of the present invention is used for phase-separating a layer containing a block copolymer in which a plurality of types of polymers are formed on a substrate. Specifically, the base agent of the present invention is obtained by coating the base agent on a substrate to provide a layer comprising the base agent, and then forming a layer containing a plurality of types of block copolymers thereon. The substrate surface on which the layer made of the base agent is formed can have high affinity with any block constituting the block copolymer.
In addition, the phase separation of the layer containing the block copolymer and the pattern forming method of the layer containing the block copolymer in which the base material of the present invention can be used will be described in the second and third aspects of the present invention.

<Resin component (A ')>
The base agent of the present invention includes a resin component (A ′) having a structural unit derived from an aromatic ring-containing monomer (hereinafter, sometimes referred to as “(A ′) component”).
In the present specification and claims, the “resin component” means a polymer having a molecular weight of 1000 or more. As the molecular weight of the polymer, a polystyrene-reduced mass average molecular weight by GPC (gel permeation chromatography) is used.

  In the present invention, the component (A ′) has a structural unit derived from an aromatic ring-containing monomer (hereinafter sometimes referred to as “structural unit (a1 ′)”).

[Structural unit (a1 ′)]
The structural unit (a1 ′) is a structural unit derived from an aromatic ring-containing monomer. Even when the component (A ′) contains a structural unit derived from an aromatic ring-containing monomer as the structural unit (a1 ′), a block copolymer having a block having various properties is used. It can have moderate affinity for it.
The aromatic ring preferably has 6 to 18 carbon atoms, specifically, an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene; a part of carbon atoms constituting the aromatic hydrocarbon ring An aromatic heterocycle in which is substituted with a hetero atom; Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom.

The structural unit (a1 ′) is not particularly limited as long as it has an aromatic ring. As the structural unit (a1 ′), for example,
-Aromatic compounds having a vinyl group (compounds containing an aromatic ring);
-Aromatic compounds having a (meth) acryloyl group;
-Phenol compounds that are constituents of novolak resins, and the like.
Among them, a structural unit derived from a compound in which one of hydrogen atoms bonded to a carbon atom forming a ring of an aromatic ring which may have a substituent is substituted with a vinyl group; A structural unit derived from acrylic acid or an ester thereof in which a hydrogen atom bonded to an atom may be substituted with a substituent, and a structural unit having an aromatic ring is preferable. Here, the vinyl group may be a group in which a carbon atom bonded to an aromatic ring is substituted with a substituent.
As the structural unit (a1 ′), a structural unit derived from styrene or a derivative thereof, vinylnaphthalene or a derivative thereof, or vinylanthracene or a derivative thereof is particularly preferable.

  As “styrene or a derivative thereof”, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, or the hydrogen atom bonded to the benzene ring may be substituted with a substituent other than a hydroxyl group. Good styrene (hereinafter, styrene in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent is referred to as “α-substituted styrene”. The styrene in which the position is not substituted and the α-substituted styrene are collectively referred to. Sometimes referred to as “(α-substituted) styrene. The same applies to other similar compounds.”) The hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, or bonded to the benzene ring. Hydroxystyrene in which a hydrogen atom may be substituted with a substituent other than a hydroxyl group (hereinafter sometimes referred to as “(α-substituted) hydroxystyrene”), a hydroxyl group of (α-substituted) hydroxystyrene A compound in which the hydrogen atom is substituted with an organic group, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and the hydrogen atom bonded to the benzene ring is a substituent other than a hydroxyl group and a carboxy group Vinyl benzoic acid which may be substituted with (hereinafter sometimes referred to as (α-substituted) vinyl benzoic acid), (α-substituted) compounds in which the hydrogen atom of the carboxy group of vinyl benzoic acid is substituted with an organic group, etc. Can be mentioned.

In α-substituted styrene, α-substituted hydroxystyrene, α-substituted vinylbenzoic acid, the substituent bonded to the α-position carbon atom is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halide having 1 to 5 carbon atoms. Group is preferable, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is more preferable, and a hydrogen atom or a methyl group is most preferable in terms of industrial availability.
The alkyl group as a substituent at the α-position is preferably a linear or branched alkyl group, and specifically includes a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert group. -A butyl group, a pentyl group, an isopentyl group, a neopentyl group, etc. are mentioned.
Specific examples of the halogenated alkyl group as the substituent at the α-position include groups in which part or all of the hydrogen atoms of the above-mentioned “alkyl group as the substituent at the α-position” are substituted with a halogen atom. It is done. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.

Hydroxystyrene is a compound in which one vinyl group and at least one hydroxyl group are bonded to a benzene ring. 1-3 are preferable and, as for the number of the hydroxyl groups couple | bonded with a benzene ring, 1 is especially preferable. The bonding position of the hydroxyl group in the benzene ring is not particularly limited. When the number of hydroxyl groups is one, the para 4-position of the vinyl group bonding position is preferred. When the number of hydroxyl groups is an integer of 2 or more, any bonding position can be combined.
Vinyl benzoic acid is a compound in which one vinyl group is bonded to the benzene ring of benzoic acid. The bonding position of the vinyl group in the benzene ring is not particularly limited.
The substituent other than the hydroxyl group and the carboxy group that may be bonded to the benzene ring of styrene or a derivative thereof is not particularly limited, and for example, a halogen atom, an alkyl group having 1 to 5 carbon atoms, Examples include halogenated alkyl groups. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.

As "vinyl naphthalene or a derivative thereof", a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and a hydrogen atom bonded to a naphthalene ring is substituted with a substituent other than a hydroxyl group. A good vinyl naphthalene (hereinafter sometimes referred to as “(α-substituted) vinyl naphthalene”), a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and a hydrogen atom bonded to the naphthalene ring may be , Vinyl (hydroxynaphthalene) optionally substituted with a substituent other than a hydroxyl group (hereinafter sometimes referred to as “(α-substituted) vinyl (hydroxynaphthalene)”), (α-substituted) hydroxyl group of vinyl (hydroxynaphthalene) And compounds in which a hydrogen atom is substituted with a substituent. In α-substituted vinylnaphthalene and α-substituted vinyl (hydroxynaphthalene), the substituent for substituting the hydrogen atom bonded to the carbon atom at the α-position is the same as the above-described substituent such as α-substituted styrene.
Vinyl (hydroxynaphthalene) is a compound in which one vinyl group and at least one hydroxyl group are bonded to a naphthalene ring. The vinyl group may be bonded to the 1-position of the naphthalene ring or may be bonded to the 2-position. 1-3 are preferable and, as for the number of the hydroxyl groups couple | bonded with a naphthalene ring, 1 is especially preferable. The bonding position of the hydroxyl group in the naphthalene ring is not particularly limited. In the case where a vinyl group is bonded to the 1-position or 2-position of the naphthalene ring, any one of the 5- to 8-positions of the naphthalene ring is preferable. In particular, when the number of hydroxyl groups is one, any one of 5 to 7 positions of the naphthalene ring is preferable, and 5 or 6 positions are preferable. When the number of hydroxyl groups is an integer of 2 or more, any bonding position can be combined.
Examples of the substituent which may be bonded to the naphthalene ring of vinyl naphthalene or a derivative thereof are the same as those described above as the substituent which may be bonded to the benzene ring of the (α-substituted) styrene.

  As "vinyl anthracene or a derivative thereof", the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and the hydrogen atom bonded to the anthracene ring is substituted with a substituent other than a hydroxyl group. Also good vinyl anthracene. The substituent is the same as the substituent such as the α-substituted styrene.

“Acrylic acid ester” is a compound in which the hydrogen atom at the carboxy group terminal of acrylic acid (CH ₂ ═CH—COOH) is substituted with an organic group.
The hydrogen atom bonded to the carbon atom at the α-position is bonded to the carbon atom at the α-position of the acrylic acid which may be substituted with a substituent (hereinafter sometimes referred to as “(α-substituted) acrylic acid”) or an ester thereof. Examples of the substituent are the same as those in the α-substituted styrene and the like in α-substituted vinylnaphthalene and α-substituted vinyl (hydroxynaphthalene). Note that the α-position (α-position carbon atom) of a structural unit derived from an acrylate ester means a carbon atom to which a carbonyl group is bonded, unless otherwise specified.
The organic group of the (α-substituted) acrylic acid ester is not particularly limited.

  As the structural unit (a1 ′), structural units represented by any of the following formulas (a1′-1) to (a1′-4) are particularly preferable.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。Ｘ^ｃ、Ｘ^ｄはそれぞれ独立に水素原子、水酸基、シアノ基または有機基である。Ｒ^ｃおよびＲ^ｄはそれぞれ独立にハロゲン原子、−ＣＯＯＸ^ｅ（Ｘ^ｅは水素原子または有機基である。）、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。ｐｘは０〜３の整数であり、ｑｘは０〜５の整数であり、ｐｘ＋ｑｘは１〜５である。ｑｘが２以上の整数である場合、複数のＲ^ｃはそれぞれ同じであっても異なってもよい。ｘは０〜３の整数であり、ｙは０〜３の整数であり、ｙ’は０〜２の整数であり、ｚは０〜４の整数であり、式（ａ１’−２）におけるｘ＋ｙ＋ｚは１〜７であり、式（ａ１’−３）におけるｘ＋ｙ＋ｙ’＋ｚは１〜７である。ｙ＋ｚ又はｙ＋ｙ’＋ｚが２以上の整数である場合、複数のＲ^ｄはそれぞれ同じであっても異なってもよい。Ｘ^Ａｒは芳香環を有する１価の有機基である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. X ^c and X ^d each independently represent a hydrogen atom, a hydroxyl group, a cyano group, or an organic group. R ^c and R ^d are each independently a halogen atom, —COOX ^e (X ^e is a hydrogen atom or an organic group), an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. . px is an integer of 0 to 3, qx is an integer of 0 to 5, and px + qx is 1 to 5. When qx is an integer of 2 or more, the plurality of R ^c may be the same or different. x is an integer of 0 to 3, y is an integer of 0 to 3, y ′ is an integer of 0 to 2, z is an integer of 0 to 4, and x + y + z in formula (a1′-2) Is 1-7, and x + y + y ′ + z in the formula (a1′-3) is 1-7. When y + z or y + y ′ + z is an integer of 2 or more, the plurality of R ^d may be the same or different. X ^Ar is a monovalent organic group having an aromatic ring. ]

  In the formula, the alkyl group and the halogenated alkyl group represented by R are the alkyl group, the halogenated alkyl group, and the like, which are mentioned as the substituents that may be bonded to the α-position carbon atom in the description of the α-substituted styrene and the like. The same thing is mentioned. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, and most preferably a hydrogen atom or a methyl group.

In the formula, the organic group of X ^c and X ^d is not particularly limited as long as it is a group containing a carbon atom. (Fluorine atom, chlorine atom, etc.), silicon atom, etc.).
As the organic group for ^Xc and ^Xd, a hydrocarbon group which may have a substituent is preferable, and an alkyl group which may have a substituent is more preferable.
Examples of the alkyl group which may have a substituent include an unsubstituted alkyl group and a substituted alkyl group in which part or all of the hydrogen atoms of the unsubstituted alkyl group are substituted with a substituent. .
The unsubstituted alkyl group may be linear, branched or cyclic. From the point which is excellent in resolution, a C1-C10 alkyl group is preferable and a C1-C5 alkyl group is more preferable. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decyl group. .
Examples of the substituent in the substituted alkyl group include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (═O), a cyano group, and the like.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
Further, it may be substituted with a substituent containing a partial hetero atom of carbon atoms constituting the unsubstituted or substituted alkyl group. Examples of the substituent containing the hetero atom include —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, —S (═O) ₂ —O—, —Si. -Is preferred.

In the formula, examples of the halogen atom represented by R ^c and R ^d include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
In -COOX ^e of R ^c and R ^d , X ^e is a hydrogen atom or an organic group, and the organic group is the same as the organic group of X ^c and X ^d described above.
Examples of the alkyl group having 1 to 5 carbon atoms and the halogenated alkyl group having 1 to 5 carbon atoms of R ^c and R ^d include the alkyl group having 1 to 5 carbon atoms and the halogenated alkyl group having 1 to 5 carbon atoms. Is the same.

X ^Ar is a monovalent organic group having an aromatic ring, and examples thereof include a group in which one or more hydrogen atoms have been removed from the above-described aromatic ring, from benzene, naphthalene or anthracene which may have a substituent. A group in which one hydrogen atom is removed is preferable.

As the structural unit (a1 ′) contained in the component (A ′), 1 type of structural unit may be used, or 2 or more types may be used.
In the component (A ′), the proportion of the structural unit (a1 ′) is preferably 10 to 95 mol%, more preferably 20 to 90 mol%, based on all the structural units constituting the component (A ′). 90 mol% is more preferable, and 50 to 85 mol% is most preferable.
By setting the proportion of the structural unit (a1 ′) to the lower limit value or more, the layer containing the block copolymer as the upper layer can be favorably phase-separated. Moreover, it becomes easy to balance with the structural unit (a2 ') mentioned later by setting it as below an upper limit.

<Optional component>
In the present invention, the component (A ′) is a structural unit having an ether-containing cyclic group (hereinafter sometimes referred to as “structural unit (a14)”), a structural unit having no aromatic ring (hereinafter referred to as “structural unit”). (A2 ') ") may be included.

[Structural unit (a14)]
The structural unit (a14) is a structural unit having an ether-containing cyclic group. In the present invention, it may have a 3- to 7-membered ether-containing cyclic group. Here, the “ether-containing cyclic group” means a cyclic group containing a structure (cyclic ether) in which carbon of a cyclic hydrocarbon is substituted with oxygen. Specifically, those represented by the following formulas (e-1) and (e-2) are preferable.

［式中、Ｒは前記同様であり、Ｘは単結合または炭素数１〜３のアルキレン基であり、ｎは１〜５であり、Ｒ_ｍは水素又は炭素数１〜５のアルキル基であり、ｎ’は０〜２であり、ｎ”は０〜２である。］

In the formula, R is the same as defined above, X is a single bond or an alkylene group having 1 to 3 carbon atoms, n is 1-5, R _m is alkyl group of 1 to 5 hydrogen or carbon , N ′ is 0 to 2, and n ″ is 0 to 2.]

  Among the structural units represented by the formulas (e-1) to (e-3), preferred specific examples are shown below.

［式中、Ｒは前記同様である。］

[Wherein, R is the same as defined above. ]

  In the present invention, the component (A) may have a structural unit having no aromatic ring (hereinafter sometimes referred to as “structural unit (a2)”).

[Structural unit (a2 ′)]
The structural unit (a2 ′) is a structural unit having no aromatic ring. The component (A ′) may be contained together with the structural unit (a1 ′) and the structural unit (a2 ′). By containing together with the structural unit (a1 ′) and the structural unit (a2 ′), it can have affinity for various structural units of the block copolymer.
The structural unit (a2 ′) is not particularly limited as long as it does not have the aromatic ring described in the structural unit (a1 ′) in its structure.
A structural unit derived from acrylic acid or an ester thereof in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and having no aromatic ring;
A structural unit derived from acrylamide or a derivative thereof in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and having no aromatic ring;
A structural unit derived from a cycloolefin or a derivative thereof having no aromatic ring;
-A structural unit derived from a vinyl sulfonic acid ester, which does not have an aromatic ring;

  Among these, a structural unit derived from acrylic acid or an ester thereof in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and the hydrogen atom bonded to the carbon atom at the α-position is a substituent. A structural unit derived from an optionally substituted acrylamide or a derivative thereof is preferred.

Examples of “acrylamide or a derivative thereof” include an acrylamide in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent (hereinafter sometimes referred to as (α-substituted) acrylamide), (α-substituted) acrylamide. Amino groups (compounds in which one or both of the terminal hydrogen atoms are substituted with a substituent, and the like).
Examples of the substituent that may be bonded to the α-position carbon atom of acrylamide or a derivative thereof are the same as those described as the substituent bonded to the α-position carbon atom of the α-substituted styrene.
As the substituent that substitutes one or both of the hydrogen atoms at the amino group terminal of (α-substituted) acrylamide, an organic group is preferable. Although it does not specifically limit as this organic group, For example, the thing similar to the organic group which the said ((alpha) substituted) acrylate ester has is mentioned.
As the compound in which one or both of the hydrogen atoms at the terminal of the amino group of (α-substituted) acrylamide are substituted with a substituent, for example, —C (= bonded to the α-position carbon atom in the above (α-substituted) acrylate ester O) —O—, —C (═O) —N (R ^b ) — [wherein R ^b is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ] Are substituted.
In the formula, the alkyl group in R ^b is preferably linear or branched.

  As the structural unit (a2 ′), structural units represented by general formula (a2′-1) or (a2′-2) shown below are particularly preferable.

［式中、Ｒは前記同様であり、Ｘ^ａ、Ｘ^ｂはそれぞれ独立に水素原子または芳香環を有しない有機基である。Ｒ^ｂは水素原子または炭素数１〜５のアルキル基である。］

[Wherein, R is the same as defined above, and X ^a and X ^b are each independently an organic group having no hydrogen atom or aromatic ring. R ^b is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. ]

In the formula, X ^a and X ^b are each independently a hydrogen atom or an organic group. The organic group is not particularly limited as long as it does not have an aromatic ring and contains a carbon atom. An atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom ( A fluorine atom, a chlorine atom, etc.), a silicon atom, etc.). Specific examples of the organic group for X ^a and X ^b include the same groups as those described for the organic group for X ^c and X ^d .
In the formula, the alkyl group having 1 to 5 carbon atoms of R ^b is the same as the alkyl group having 1 to 5 carbon atoms of R.

As the structural unit (a2 ′) contained in the component (A ′), 1 type may be used, or 2 or more types may be used.
In the component (A), the proportion of the structural unit (a2 ′) is preferably from 5 to 90 mol%, more preferably from 10 to 80 mol%, more preferably from 10 to 70, based on all structural units constituting the component (A ′). More preferred is mol%, and most preferred is 15 to 50 mol%.
By setting the proportion of the structural unit (a2 ′) to the lower limit value or more, the layer containing the block copolymer as the upper layer can be favorably phase-separated. Moreover, it becomes easy to balance with a structural unit (a1 ') by setting it as below an upper limit.

{Substrate interaction group}
The component (A ′) of the present invention may have a substrate interaction group. When the component (A ′) has a substrate interaction group, the base agent containing the component (A ′) interacts with the substrate, and a strong film (a layer made of the base agent) is formed on the substrate. As a result, it is considered that the layer made of the block copolymer is excellently phase-separated on the layer made of the base agent.
In the present invention, the “group capable of interacting with a substrate” and the “substrate interacting group” are groups capable of chemically or physically interacting with a substrate, depending on the type of the substrate. It can be selected appropriately. The type of interaction between the substrate and the substrate interaction group includes covalent interaction, ionic bond interaction, hydrogen bond interaction, electrostatic interaction, hydrophobic interaction, van der Waals force bonding, etc. Is mentioned.
Specific examples of the substrate interaction group include a carboxy group, a cyano group, an amino group or a trialkoxysilyl group, a dialkoxysilyl group, a monoalkoxysilyl group, and the like. Among them, a carboxy group, a cyano group, an amino group, or a trialkoxy group. A silyl group is preferred. As the alkoxy group in the trialkoxysilyl group, a methoxy group or an ethoxy group is preferable, and a methoxy group is particularly preferable.

In the present invention, the substrate interaction group is preferably a lactone-containing cyclic group.
The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing —O—C (═O) — in the ring skeleton. The lactone ring is counted as the first ring. When only the lactone ring is present, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group as the cyclic hydrocarbon group as the substrate interaction group is not particularly limited, and any one can be used. Specific examples include groups represented by the following general formulas (lc-r-1) to (lc-r-7). Hereinafter, “*” represents a bond.

［式中、Ｒａ’^２１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０〜２の整数であり、ｍ’は０または１である。］

[Wherein, Ra ′ ²¹ each independently represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group. Yes; R ″ is a hydrogen atom or an alkyl group; A ″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n ′ is 0 to 2 And m ′ is 0 or 1. ]

In the general formulas (lc-r-1) to (lc-r-7), A ″ has 1 to 5 carbon atoms which may contain an oxygen atom (—O—) or a sulfur atom (—S—). The alkylene group having 1 to 5 carbon atoms in A ″ is preferably a linear or branched alkylene group, a methylene group, an ethylene group, an n-propylene group, An isopropylene group etc. are mentioned. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which —O— or —S— is interposed between the terminal or carbon atoms of the alkylene group, such as —O—CH _{2. -, - CH 2 -O-CH} 2 -, - S-CH 2 -, - CH 2 -S-CH 2 - , and the like. A ″ is preferably an alkylene group having 1 to 5 carbon atoms or —O—, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group. Ra ′ ²¹ independently represents an alkyl group or an alkoxy group. A group, a halogen atom, a halogenated alkyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group.
The alkyl group in ra ^'21, preferably an alkyl group having 1 to 5 carbon atoms.
The alkoxy group in the ra ^'21, preferably an alkoxy group having 1 to 6 carbon atoms.
The alkoxy group is preferably linear or branched. Specifically, groups of the the Ra 'group and an oxygen atom mentioned as the alkyl group in ²¹ (-O-) are linked and the like.
Examples of the halogen atom in Ra ′ ²¹ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
'Examples of the halogenated alkyl group for ^21, the Ra' Ra part or all of the hydrogen atoms of the alkyl group in ²¹ can be mentioned it has been substituted with the aforementioned halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.

In —COOR ″ and —OC (═O) R ″ in Ra ′ ²¹ , R ″ is a hydrogen atom or an alkyl group.

  In the present invention, among the above, a group represented by (lc-r-1) or (lc-r-2) is preferable.

  Specific examples of groups represented by general formulas (lc-r-1) to (lc-r-7) are given below.

  In the present invention, examples of the lactone-containing cyclic group include (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r- group represented by lc-2-13) is preferable, and groups represented by (r-lc-1-1) to (r-lc-1-7) are particularly preferable.

In the present invention, the substrate interaction group may be an organic group containing a fluorine atom. The organic group containing a fluorine atom is preferably a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms. The carbon number of 1 to 10 is particularly preferable.
The hydrocarbon group containing a fluorine atom preferably has 25% or more of the hydrogen atoms in the hydrocarbon group fluorinated, more preferably 50% or more fluorinated, and 60% or more. Fluorination is particularly preferable because the hydrophobicity of the resist film during immersion exposure is increased.
Among them, in the present invention, particularly preferably a fluorinated hydrocarbon group having 1 to 5 carbon atoms, a methyl _{group, -CH 2 -CF 3, -CH 2} -CF 2 -CF 3, -CH (CF 3) 2 _{, -CH} 2 _-CH 2 _-CF 3, and most preferably _{-CH 2 -CH 2 -CF 2 -CF 2} -CF 2 -CF 3.

The substrate interaction group may be included in the structural unit (a1 ′) or the structural unit (a2 ′). Especially, it is preferable that a structural unit (a2 ') has a board | substrate interaction group. Hereinafter, the structural unit (a2 ′) having a substrate interaction group is referred to as a structural unit (a21).
As the structural unit (a21), structural units represented by general formulas (a21-1) to (a21-2) shown below are preferable.

［式中、Ｒ、Ｒ^ｂは前記同様であり、Ｙ^０１は単結合、又は、芳香環を有しない２価の連結基であり、Ｘ^０１は水素原子、カルボキシ基、シアノ基、アミノ基又はトリアルコキシシリル基である。但し、Ｘ^０１が水素原子の場合、Ｙ^０１は単結合となり、Ｘ^０１がカルボキシ基、シアノ基、アミノ基又はトリアルコキシシリル基の場合、Ｙ^０１は芳香環を有しない２価の連結基となる。Ｙ^０２は芳香環を有しない２価の連結基であり、Ｘ^０２はカルボキシ基、シアノ基、アミノ基又はトリアルコキシシリル基である。］

[Wherein, R and R ^b are the same as above, Y ⁰¹ is a single bond or a divalent linking group having no aromatic ring, and X ⁰¹ is a hydrogen atom, a carboxy group, a cyano group, an amino group or It is a trialkoxysilyl group. However, when X ⁰¹ is a hydrogen atom, Y ⁰¹ is a single bond, and when X ⁰¹ is a carboxy group, a cyano group, an amino group, or a trialkoxysilyl group, Y ⁰¹ is a divalent linking group having no aromatic ring. Become. Y ⁰² is a divalent linking group having no aromatic ring, and X ⁰² is a carboxy group, a cyano group, an amino group, or a trialkoxysilyl group. ]

In the above formula, Y ⁰¹ may be a single bond or a divalent linking group having no aromatic ring. The divalent linking group for Y ⁰¹ is not particularly limited as long as it does not have an aromatic ring, but may have a substituent, a divalent hydrocarbon group that does not have an aromatic ring; Preferred examples include a divalent linking group containing no aromatic ring.

(Divalent hydrocarbon group which may have a substituent)
The hydrocarbon group as a divalent linking group having no aromatic ring is preferably an aliphatic hydrocarbon group.
An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in the structure, and the like.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 5 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as - _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.
The linear or branched aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and an oxo group (═O).

As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (excluding two hydrogen atoms from the aliphatic hydrocarbon ring) Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is a linear or branched chain fatty acid. Group intervening in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those described above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic aliphatic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, Examples include norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The cyclic aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (═O).
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, and —S (═O) ₂ —O— are preferable.

(Divalent linking group containing a hetero atom)
The hetero atom in the “divalent linking group containing a hetero atom” of Y ⁰ is an atom other than a carbon atom and a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom.
Examples of the divalent linking group containing a hetero atom include -O-, -C (= O) -O-, -C (= O)-, -O-C (= O) -O-, -C (= O) —NH—, —NH— (H may be substituted with a substituent such as an alkyl group, an acyl group, etc.), —S—, —S (═O) ₂ —, —S (═O) _{2 -O -, - NH-C} (= O) -, = N-, the formula ^{-Y 21 -O-Y 22 -,} - [Y 21 -C (= O) -O] m '-Y 22 - , —C (═O) —O—Y ²² — or —Y ²¹ —O—C (═O) —Y ²² —, wherein Y ²¹ and Y ²² are each independently a substituent. Is a divalent hydrocarbon group which may have, O is an oxygen atom, and m ′ is an integer of 0-3. ] Etc. are mentioned.
When Y ⁰ is —NH—, the H may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, aryl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same groups as those described above as the “divalent hydrocarbon group optionally having substituent (s)” for Y ⁰ .
Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, and more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² —, m ′ is an integer of 0 to 3, preferably an integer of 0 to 2, Or 1 is more preferable, and 1 is particularly preferable. That is, the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — is represented by the formula —Y ²¹ —C (═O) —O—Y ²² —. The group is particularly preferred. Among these, a group represented by the formula — (CH ₂ ) _{a ′} —C (═O) —O— (CH ₂ ) _{b ′} — is preferable. In the formula, a ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1.
Examples of the divalent linking group containing a hetero atom, a linear group containing an oxygen atom as a hetero atom, for example, a group containing an ether bond or an ester bond, are preferred, the formula -Y 21 ^-O-Y 22 ^-, A group represented by — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (═O) —Y ²² — is more preferable.

Among these, as the divalent linking group for Y ⁰¹ , in particular, a linear or branched alkylene group, a divalent alicyclic hydrocarbon group, or a divalent linking group containing a hetero atom is included. preferable. Among these, a linear or branched alkylene group or a divalent linking group containing an ester bond (—C (═O) —O—) is preferable.

In the formula, X ⁰¹ is a hydrogen atom, a carboxy group, a cyano group, an amino group or a trialkoxysilyl group, the alkoxy group in the trialkoxysilyl group is the same as described above, and the trialkoxysilyl group is a trimethoxysilyl group. Groups are preferred.
Wherein, Y ⁰² is a divalent linking group having no aromatic ring, the same as the divalent linking group having no aromatic ring of the Y ^01.
Trialkoxysilyl groups X ⁰² are the same as trialkoxysilyl groups of the X ^01.

  Specific examples of the structural unit (a21) are shown below. In the formula, R is the same as described above.

As the structural unit (a21), one type may be used alone, or two or more types may be used in combination.
5-100 mol% is preferable and, as for the ratio of the structural unit (a21) in a structural unit (a2 '), 10-100 mol% is more preferable. That is, the structural unit (a2 ′) may be composed only of the structural unit (a21).

The mass average molecular weight (Mw) of the component (A ′) (polystyrene conversion standard by gel permeation chromatography (GPC)) is not particularly limited, preferably 1000 to 200000, more preferably 1500 to 200000, 2000 ˜150,000 is most preferred. If it is below the upper limit of this range, it will be sufficiently dissolved in an organic solvent as will be described later, so it is excellent in coatability to the substrate, and if it is above the lower limit of this range, it will be excellent in polymer production stability, and It becomes the composition excellent in the applicability | paintability to a board | substrate.
The dispersity (Mw / Mn) is not particularly limited, but is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.0 to 2.5. In addition, Mn shows a number average molecular weight.

The component (A ′) can be obtained by polymerizing a monomer for deriving each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN). .
In addition, for the component (A ′), in the polymerization, a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH is used in combination, -C terminated _{(CF 3)} may be introduced 2 -OH group.
A commercially available monomer may be used as the monomer for deriving each structural unit, or the monomer may be synthesized using a known method.

In the base agent of the present invention, as the component (A ′), one type may be used alone, or two or more types may be used in combination.
What is necessary is just to adjust suitably content of (A ') component in the base agent of this invention according to the desired film thickness etc. of the layer which consists of base agents.

<Acid generator component; (B) component>
The resist composition of the present invention contains an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as (B) component). The component (B) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resists can be used.
Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, and diazomethanes such as poly (bissulfonyl) diazomethanes. Examples include an acid generator, a nitrobenzyl sulfonate acid generator, an imino sulfonate acid generator, and a disulfone acid generator. Of these, it is preferable to use an onium salt acid generator.

  Examples of the onium salt-based acid generator include a compound represented by the following general formula (b-1) (hereinafter also referred to as “(b-1) component”) and a general formula (b-2). A compound (hereinafter also referred to as “(b-2) component”) or a compound represented by the general formula (b-3) (hereinafter also referred to as “(b-3) component”) can be used.

［式中、Ｒ^１０１、Ｒ^１０４〜Ｒ^１０８はそれぞれ独立に置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基である。Ｒ^１０４、Ｒ^１０５は、相互に結合して環を形成していてもよい。Ｒ^１０６〜Ｒ^１０７のいずれか２つは、相互に結合して環を形成していてもよい。Ｒ^１０２はフッ素原子または炭素数１〜５のフッ素化アルキル基である。Ｙ^１０１は単結合または酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３はそれぞれ独立に単結合、アルキレン基、またはフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２はそれぞれ独立に単結合または酸素原子である。Ｌ^１０３〜Ｌ^１０５はそれぞれ独立に単結合、−ＣＯ−又は−ＳＯ_２−である。Ｍ’^ｍ＋はｍ価の有機カチオンである（前記式（ｂ１−１）の化合物におけるカチオンを除く）。］

[Wherein, R ¹⁰¹ and R ^{104 to} R ¹⁰⁸ each independently has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. A chain alkenyl group which may be present. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring. Any two of R ^{106 to} R ¹⁰⁷ may be bonded to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ^{101 to} V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group. L ^{101 to} L ¹⁰² are each independently a single bond or an oxygen atom. L ^{103 to} L ¹⁰⁵ are each independently a single bond, —CO— or —SO ₂ —. M ′ ^{m +} is an m-valent organic cation (excluding the cation in the compound of the formula (b1-1)). ]

{Anion part}
-Anion moiety of component (b-1) In formula (b-1), R ¹⁰¹ represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, Alternatively, a chain alkenyl group which may have a substituent.

(Cyclic group which may have a substituent)
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group.
The aromatic hydrocarbon group in R ¹⁰¹ is an aromatic hydrocarbon ring mentioned in the divalent aromatic hydrocarbon group in Va ¹ of formula (a1-1) described later, or an aromatic compound containing two or more aromatic rings. An aryl group in which one hydrogen atom is removed from the aryl group, and a phenyl group and a naphthyl group are preferable.
The cyclic aliphatic hydrocarbon group in R ¹⁰¹ is obtained by removing one hydrogen atom from the monocycloalkane or polycycloalkane mentioned in the divalent aliphatic hydrocarbon group in Va ¹ of formula (a1-1) described later. Group, and an adamantyl group and a norbornyl group are preferable.
In addition, the cyclic hydrocarbon group in R ¹⁰¹ may contain a hetero atom such as a heterocycle, and specifically, in the general formulas (a2-r-1) to (a2-r-7) described later, respectively. Lactone-containing cyclic groups represented by formulas, —SO ₂ -containing cyclic groups represented by general formulas (a5-r-1) to (a5-r-4) described later, and other heterocyclic groups listed below. Is mentioned.

Examples of the substituent in the cyclic hydrocarbon group of R ¹⁰¹ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group.
The alkyl group as a substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
As the halogenated alkyl group as a substituent, a part or all of hydrogen atoms such as an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group, And a group substituted with a halogen atom.

(A chain alkyl group which may have a substituent)
The chain alkyl group for R ¹⁰¹ may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group Group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group and the like.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

(Chain-like alkenyl group which may have a substituent)
The chain alkenyl group for R ¹⁰¹ may be either linear or branched, preferably has 2 to 10 carbon atoms, more preferably 2 to 5, still more preferably 2 to 4, more preferably 3 Is particularly preferred. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched alkenyl group include a 1-methylpropenyl group and a 2-methylpropenyl group.
Among the above, the chain alkenyl group is particularly preferably a propenyl group.

Examples of the substituent in the chain alkyl group or alkenyl group of R ¹⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and the cyclic group in R ¹⁰¹ described above. Can be mentioned.

Among these, R ¹⁰¹ is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, each group is represented by a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and formulas (a2-r-1) to (a2-r-7) described later. Lactone-containing cyclic groups, —SO ₂ -containing cyclic groups represented by general formulas (a5-r-1) to (a5-r-4) described later, and the like are preferable.

In formula (b-1), Y ¹⁰¹ represents a single bond or a divalent linking group containing an oxygen atom.
When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, Y ¹⁰¹ may contain an atom other than an oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: —O—), an ester bond (—C (═O) —O—), and an oxycarbonyl group (—O—C (═O). )-), Amide bond (—C (═O) —NH—), carbonyl group (—C (═O) —), carbonate bond (—O—C (═O) —O—), etc. A combination of a non-hydrocarbon oxygen atom-containing linking group and an alkylene group; and the like. A sulfonyl group (—SO ₂ —) may be further linked to the combination. Examples of the combination include linking groups represented by the following formulas (y-al-1) to (y-al-7), respectively.

［式中、Ｖ’^１０１は単結合または炭素数１〜５のアルキレン基であり、Ｖ’^１０２は炭素数１〜３０の２価の飽和炭化水素基である。］

[Wherein, V ′ ¹⁰¹ is a single bond or an alkylene group having 1 to 5 carbon atoms, and V ′ ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms. ]

The divalent saturated hydrocarbon group for V ′ ¹⁰² is preferably an alkylene group having 1 to 30 carbon atoms.

The alkylene group for V ′ ¹⁰¹ and V ′ ¹⁰² may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferred.
Specific examples of the alkylene group in V ′ ¹⁰¹ and V ′ ¹⁰² include a methylene group [—CH ₂ —]; —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as ethylene Groups [—CH ₂ CH ₂ —]; —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH (CH ₃ ) —, —C (CH ₃ ) ₂ CH ₂ —, —CH (CH ₂ CH - ₃₎ CH ₂ alkyl groups such as, trimethylene group (n- propylene _{group) [- CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 -, - CH 2 CH (CH 3) CH ₂ - and the like alkyl trimethylene group; tetramethylene _{[-CH 2 CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 CH 2 - alkyl tetramethylene group and the like; pentamethylene group _{[-CH 2 CH 2 CH 2 CH} 2 CH 2 -] , and the like.
Moreover, some methylene groups in the alkylene group in V ′ ¹⁰¹ or V ′ ¹⁰² may be substituted with a C 5-10 divalent aliphatic cyclic group. The aliphatic cyclic group is preferably a divalent group obtained by further removing one hydrogen atom from the cyclic aliphatic hydrocarbon group of Ra ′ ³ in formula (a1-r-1) described later. A group, 1,5-adamantylene group or 2,6-adamantylene group is more preferable.

Y ¹⁰¹ is preferably a divalent linking group containing an ester bond or an ether bond, and linking groups represented by the above formulas (y-al-1) to (y-al-5) are preferred.

In formula (b-1), V ¹⁰¹ represents a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group and fluorinated alkylene group for V ¹⁰¹ preferably have 1 to 4 carbon atoms. ^Examples of the fluorinated alkylene group for V ¹⁰¹ include groups in which some or all of the hydrogen atoms of the alkylene group for V ¹⁰¹ have been substituted with fluorine atoms. Among ^{them, V 101} is preferably a single bond, or a fluorinated alkylene group having 1 to 4 carbon atoms.

In formula (b-1), R ¹⁰² represents a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰² is preferably a fluorine atom or a C 1-5 perfluoroalkyl group, and more preferably a fluorine atom.

As a specific example of the anion part of the component (b-1), for example,
When Y ¹⁰¹ is a single bond, fluorinated alkyl sulfonate anions such as trifluoromethane sulfonate anion and perfluorobutane sulfonate anion can be mentioned; when Y ¹⁰¹ is a divalent linking group containing an oxygen atom, the following formula (an An anion represented by any one of (-1) to (an-3).

［式中、Ｒ”^１０１は、置換基を有していてもよい脂肪族環式基、前記式（ｒ−ｈｒ−１）〜（ｒ−ｈｒ−６）でそれぞれ表される基、又は置換基を有していてもよい鎖状のアルキル基であり；Ｒ”^１０２は、置換基を有していてもよい脂肪族環式基、後述の式（ａ２−ｒ−１）〜（ａ２−ｒ−７）でそれぞれ表されるラクトン含有環式基、又は後述の一般式（ａ５−ｒ−１）〜（ａ５−ｒ−４）でそれぞれ表される−ＳＯ_２−含有環式基であり；Ｒ”^１０３は、置換基を有していてもよい芳香族環式基、置換基を有していてもよい脂肪族環式基、又は置換基を有していてもよい鎖状のアルケニル基であり；Ｖ”^１０１は、フッ素化アルキレン基であり；Ｌ”^１０１は、−Ｃ（＝Ｏ）−又は−ＳＯ_２−であり；ｖ”はそれぞれ独立に０〜３の整数であり、ｑ”はそれぞれ独立に１〜２０の整数であり、ｎ”は０または１である。］

[Wherein R ″ ¹⁰¹ represents an aliphatic cyclic group which may have a substituent, a group represented by each of the above formulas (r-hr-1) to (r-hr-6), or a substituent. A chain-like alkyl group which may have a group; R ″ ¹⁰² represents an aliphatic cyclic group which may have a substituent, and the following formulas (a2-r-1) to (a2- a lactone-containing cyclic group represented by each of r-7), or a —SO ₂ -containing cyclic group represented by each of general formulas (a5-r-1) to (a5-r-4) described later. R ″ ¹⁰³ represents an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl which may have a substituent; a ^{group; V "101} is an fluorinated alkylene ^{group; L" 101} is, -C (= O) - or -SO ₂ - a and; v "each independently 0 Is 3 integer, q "are each independently an integer of 1 to 20, n" is 0 or 1. ]

The aliphatic cyclic group which may have a substituent of R ″ ¹⁰¹ , R ″ ¹⁰² and R ″ ¹⁰³ is preferably the group exemplified as the cyclic aliphatic hydrocarbon group in R ¹⁰¹ . Examples of the substituent include the same substituents that may substitute the cyclic aliphatic hydrocarbon group in R ¹⁰¹ .

The aromatic cyclic group which may have a substituent in R ″ ¹⁰³ is preferably the group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in R ¹⁰¹ . , R ¹⁰¹ and the same substituents that may be substituted for the aromatic hydrocarbon group.

The chain alkyl group which may have a substituent in R ″ ¹⁰¹ is preferably the group exemplified as the chain alkyl group in R ^101. The chain in R ″ ¹⁰³ has a substituent. The good chain alkenyl group is preferably the group exemplified as the chain alkenyl group in R ¹⁰¹ . V ″ ¹⁰¹ is preferably a fluorinated alkylene group having 1 to 3 carbon atoms, and particularly preferably —CF ₂ —, —CF ₂ CF ₂ —, —CHFCF ₂ —, —CF (CF ₃ ) CF ₂ —. , —CH (CF ₃ ) CF ₂ —.

-Anion part of component (b-2) In formula (b-2), R ¹⁰⁴ and R ¹⁰⁵ may each independently have a cyclic group which may have a substituent or a substituent. Examples thereof include a good chain alkyl group or a chain alkenyl group which may have a substituent, and examples thereof include the same as those described above for R ¹⁰¹ in formula (b-1). However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring.
R ¹⁰⁴ and R ¹⁰⁵ are preferably a chain alkyl group which may have a substituent, and are a linear or branched alkyl group, or a linear or branched fluorinated alkyl group. It is more preferable.
The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and still more preferably 1 to 3 carbon atoms. The carbon number of the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible for reasons such as good solubility in a resist solvent within the above carbon number range. In addition, in the chain alkyl group of R ¹⁰⁴ and R ^105, the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, and against high-energy light and electron beams of 200 nm or less Since transparency improves, it is preferable. The proportion of fluorine atoms in the chain alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are substituted with fluorine atoms. Perfluoroalkyl group.
In formula (b-2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and each of them is the same as V ¹⁰¹ in formula (b-1). Can be mentioned.
In formula (b-2), L ^{101 to} L ¹⁰² each independently represents a single bond or an oxygen atom.

-Anion part of (b-3) component In formula (b-3), R < ¹⁰⁶ > -R < ¹⁰⁸ > may have the cyclic group which may have a substituent, and a substituent each independently. Examples thereof include a good chain alkyl group or a chain alkenyl group which may have a substituent, and examples thereof include the same as those described above for R ¹⁰¹ in formula (b-1).
L ^{103 to} L ¹⁰⁵ are each independently a single bond, —CO— or —SO ₂ —.

{Cation part}
In the formulas (b-1), (b-2) and (b-3), M ′ ^{m +} is an m-valent organic cation other than the cation in the compound of the formula (b1-1), and in particular, a sulfonium cation Or it is preferable that it is an iodonium cation, and the cation respectively represented by the following general formula (ca-1)-(ca-4) is especially preferable.

［式中、Ｒ^２０１〜Ｒ^２０７、およびＲ^２１１〜Ｒ^２１２は、それぞれ独立に置換基を有していてもよいアリール基、アルキル基またはアルケニル基を表し、Ｒ^２０１〜Ｒ^２０３、Ｒ^２０６〜Ｒ^２０７、Ｒ^２１１〜Ｒ^２１２は、相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｒ^２０８〜Ｒ^２０９はそれぞれ独立に水素原子または炭素数１〜５のアルキル基を表し、Ｒ^２１０は置換基を有していてもよいアリール基、アルキル基、アルケニル基、又は−ＳＯ_２−含有環式基であり、Ｌ^２０１は−Ｃ（＝Ｏ）−または−Ｃ（＝Ｏ）−Ｏ−を表し、Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基またはアルケニレン基を表し、ｘは１または２であり、Ｗ^２０１は（ｘ＋１）価の連結基を表す。］

[Wherein, R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² each independently represents an aryl group, an alkyl group or an alkenyl group which may have a substituent, and R ^{201 to} R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ and R ^{211 to} R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ²¹⁰ is an aryl group, alkyl group, alkenyl group, or —SO ₂ — containing an optionally substituted substituent. A cyclic group, L ²⁰¹ represents —C (═O) — or —C (═O) —O—, Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group, and x represents 1 or 2 and W ²⁰¹ represents a (x + 1) -valent linking group. ]

Examples of the aryl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.
The alkyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² is a chain or cyclic alkyl group and preferably has 1 to 30 carbon atoms.
The alkenyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² preferably has 2 to 10 carbon atoms.
Examples of the substituent that R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and an arylthio group. And groups represented by the following formulas (ca-r-1) to (ca-r-7).
The aryl group in the arylthio group as a substituent is the same as that described for R ¹⁰¹ , and specifically includes a phenylthio group or a biphenylthio group.

［式中、Ｒ’^２０１はそれぞれ独立に、水素原子、置換基を有していてもよい環式基、鎖状のアルキル基、または鎖状のアルケニル基である。］

[Wherein, R ′ ²⁰¹ each independently represents a hydrogen atom, an optionally substituted cyclic group, a chain alkyl group, or a chain alkenyl group. ]

The cyclic group which may have a substituent of R ′ ^201, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent are as described above. In addition to those similar to R ^{101 in} formula (b-1), the cyclic group which may have a substituent or the chain alkyl group which may have a substituent may have the following formula: The same thing as the acid dissociable group represented by (a1-r-2) is also mentioned.

^{R 201 ~R 203, R 206 ~R} 207, R 211 ~R 212 , when bonded to each other to form a ring with the sulfur atom, a sulfur atom, an oxygen atom, or a hetero atom such as nitrogen atom, carbonyl _{group, -SO -, - SO 2 -} , - SO 3 -, - COO -, - CONH- , or -N _(R N) - (. the _{R N} is an alkyl group having 1 to 5 carbon atoms), etc. You may couple | bond through the functional group of. As the ring to be formed, one ring containing a sulfur atom in the ring skeleton in the formula is preferably a 3- to 10-membered ring, particularly a 5- to 7-membered ring, including the sulfur atom. preferable. Specific examples of the ring formed include, for example, thiophene ring, thiazole ring, benzothiophene ring, thianthrene ring, benzothiophene ring, dibenzothiophene ring, 9H-thioxanthene ring, thioxanthone ring, thianthrene ring, phenoxathiin ring, tetrahydro A thiophenium ring, a tetrahydrothiopyranium ring, etc. are mentioned.

R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when formed into an alkyl group, they are bonded to each other to form a ring. May be formed.

R ²¹⁰ may have an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent. -SO ₂ - containing cyclic group.
The aryl group in R ^210, include unsubstituted aryl group having 6 to 20 carbon atoms, a phenyl group, a naphthyl group.
The alkyl group for R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group for R ²¹⁰ preferably has 2 to 10 carbon atoms.
The —SO ₂ — containing cyclic group which may have a substituent in R ²¹⁰ is the same as the “—SO ₂ — containing cyclic group” of Ra ^{21 in} the general formula (a2-1). The group represented by the general formula (a5-r-1) is preferable.

Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group.
Examples of the arylene group for Y ²⁰¹ include a group in which one hydrogen atom has been removed from the aryl group exemplified as the aromatic hydrocarbon group for R ¹⁰¹ in the above formula (b-1).
As the alkylene group and alkenylene group for Y ²⁰¹ , the same aliphatic hydrocarbon groups as divalent hydrocarbon groups for Va ¹ in the general formula (a1-1) described later can be used.

In the formula (ca-4), x is 1 or 2.
W ²⁰¹ is a (x + 1) valent, that is, a divalent or trivalent linking group.
The divalent linking group in W ²⁰¹ is preferably a divalent hydrocarbon group which may have a substituent, and examples thereof include the same hydrocarbon groups as Ya ²¹ in the general formula (a2-1). The divalent linking group in W ²⁰¹ may be linear, branched or cyclic, and is preferably cyclic. Of these, a group in which two carbonyl groups are combined at both ends of the arylene group is preferable. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferable.
^Examples of the trivalent linking group in W ²⁰¹ include a group obtained by removing one hydrogen atom from the divalent linking group in W ²⁰¹ , a group in which the divalent linking group is further bonded to the divalent linking group, and the like. Can be mentioned. The trivalent linking group in W ²⁰¹ is preferably a group in which two carbonyl groups are bonded to an arylene group.

  Specific examples of suitable cations represented by the formula (ca-1) include cations represented by the following formulas (ca-1-1) to (ca-1-63), respectively.

［式中、ｇ１、ｇ２、ｇ３は繰返し数を示し、ｇ１は１〜５の整数であり、ｇ２は０〜２０の整数であり、ｇ３は０〜２０の整数である。］

[Wherein, g1, g2, and g3 represent the number of repetitions, g1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20. ]

［式中、Ｒ”^２０１は水素原子又は置換基であって、置換基としては前記Ｒ^２０１〜Ｒ^２０７、およびＲ^２１０〜Ｒ^２１２が有していてもよい置換基として挙げたものと同様である。］

[Wherein R ″ ²⁰¹ is a hydrogen atom or a substituent, and the substituent is the same as the substituents that R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have. is there.]

  Specific examples of suitable cations represented by the formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

  Specific examples of suitable cations represented by the formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

As the component (B), one type of acid generator described above may be used alone, or two or more types may be used in combination.
It is preferable that the base agent of this invention contains 5-50 mass parts of acid generator components (B) with respect to 100 mass parts of said resin components (A '). Moreover, it is more preferable that 10-50 mass parts of acid generator components (B) are included with respect to 100 mass parts of said resin component (A ').

When using the base agent of this invention by the pattern formation method 1 mentioned later, it is preferable that 5-50 mass parts of acid generator components (B) are included with respect to 100 mass parts of said resin components (A '), 20 It is more preferable to contain -50 mass parts, and it is especially preferable to contain 25-50 mass parts.
When using the base agent of this invention by the pattern formation method 2 mentioned later, it is preferable that 5-50 mass parts of acid generator components (B) are included with respect to 100 mass parts of said resin components (A '), 8 It is more preferable to contain -50 mass parts, and it is especially preferable to contain 10-50 mass parts.

  In the present invention, by setting the content of the acid generator (B) in the base agent within the above range, when the guide pattern is used in the pattern forming method of the present invention to be described later, the acid is also removed from the base agent during exposure. It is considered that the deprotection of the guide pattern is promoted and the scum of the guide pattern can be reduced. In addition, by making the content of the acid generator within the above range, the hydrophilicity of the surface of the base agent can be improved moderately, the hydrophilicity can be controlled, and the layer containing the block copolymer is phase-separated. It is considered that the phase separation shape can be controlled when used as a base agent.

  The base agent of the present invention may further include a miscible additive, for example, an additional resin for improving the performance of the layer made of the base agent, a surfactant for improving coatability, and a dissolution inhibitor, as desired. Further, a plasticizer, a stabilizer, a colorant, an antihalation agent, a dye, a sensitizer, a base proliferating agent, a basic compound, a nitrogen-containing basic compound such as imidazole, and the like can be appropriately added and contained.

[Organic solvent; component (S)]
The base agent of the present invention can be produced by dissolving the material in an organic solvent (hereinafter also referred to as “(S) component”).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution. One or two or more can be appropriately selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; Monohydric alcohols; compounds having an ester bond, such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl of the polyhydric alcohols or compound having the ester bond Ether alkyl such as ether, monopropyl ether, monobutyl ether or monophenyl ether Derivatives of polyhydric alcohols such as compounds having a propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME) among these]; cyclic ethers such as dioxane, methyl lactate, Esters such as ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, Aromatic organics such as dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene A solvent etc. can be mentioned.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range. For example, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3. When PGME and cyclohexanone are blended as polar solvents, the mass ratio of PGMEA: (PGME + cyclohexanone) is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, and still more preferably 3. : 7 to 7: 3.
In addition, as the component (S), PGMEA, EL or a mixed solvent of PGMEA and a polar solvent and a mixed solvent of γ-butyrolactone are also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of the component (S) used is not particularly limited and is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. In general, the solid content concentration of the base agent is 1 -20% by mass, preferably 2-15% by mass.

<< Pattern Forming Method 1 >>
In a second aspect of the present invention, a step of applying the base agent on a substrate to form a layer made of the base agent, and then generating an acid on the layer made of the base agent by exposure. A step of forming a resist film by applying a resist composition whose solubility in a developer is changed by the action of an acid; a step of exposing the resist film; and a step of developing the resist film to form a resist pattern And forming a layer containing a block copolymer in which a plurality of types of blocks are bonded on the layer made of the base material on which the resist pattern is formed, and then phase-separating the layer containing the block copolymer, and A step of selectively removing a phase composed of at least one block of a plurality of types of blocks constituting the block copolymer from the layer containing the block copolymer; A pattern forming method characterized by having.
Hereinafter, the pattern forming method of the present invention will be specifically described with reference to FIG. However, the present invention is not limited to this.

[Step of coating the base material on the substrate and forming a layer comprising the base material]
In the pattern forming method of the present invention, first, the base agent is applied onto a substrate to form a layer made of the base agent.

<Board>
If the board | substrate 11 can apply | coat the solution containing a block copolymer on the surface, the kind will not be specifically limited. For example, metals such as silicon, copper, chromium, iron, and aluminum, substrates made of inorganic materials such as glass, titanium oxide, silica, and mica, substrates made of organic compounds such as acrylic plates, polystyrene, cellulose, cellulose acetate, and phenol resins Is mentioned.
Moreover, the magnitude | size and shape of the board | substrate 1 used in this invention are not specifically limited. The substrate 11 does not necessarily have a smooth surface, and substrates of various materials and shapes can be appropriately selected. For example, a substrate having a curved surface, a flat plate having an uneven surface, and a substrate having various shapes such as a thin piece can be used.

In addition, an inorganic and / or organic film may be provided on the surface of the substrate 11. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include an organic antireflection film (organic BARC).
The inorganic film can be formed, for example, by coating an inorganic antireflection film composition such as a silicon-based material on a substrate and baking.
The organic film is, for example, a material for forming an organic film in which a resin component or the like constituting the film is dissolved in an organic solvent is applied onto a substrate with a spinner or the like, preferably 200 to 300 ° C., preferably 30 to 300. It can be formed by baking for 2 seconds, more preferably 60 to 180 seconds. The organic film forming material used at this time does not necessarily require sensitivity to light or an electron beam, such as a resist film, and may or may not have such sensitivity. Good. Specifically, resists and resins generally used in the manufacture of semiconductor elements and liquid crystal display elements can be used.
In addition, the organic film forming material can be etched, particularly dry-etched so that the organic film can be formed by etching the organic film using a block copolymer pattern to transfer the pattern to the organic film. A material capable of forming an organic film is preferable. Among these, a material capable of forming an organic film capable of etching such as oxygen plasma etching is preferable. Such an organic film forming material may be a material conventionally used for forming an organic film such as an organic BARC. Examples include the ARC series manufactured by Brewer Science, the AR series manufactured by Rohm and Haas, and the SWK series manufactured by Tokyo Ohka Kogyo.

Before forming the layer 12 made of the base agent of the first aspect of the present invention on the substrate, the surface of the substrate 11 may be cleaned in advance. By cleaning the substrate surface, the base agent may be applied satisfactorily.
As the cleaning treatment, a conventionally known method can be used, and examples thereof include oxygen plasma treatment, ozone oxidation treatment, acid-alkali treatment, and chemical modification treatment.

The method for applying the base agent of the first aspect onto the substrate 11 to form the layer 12 made of the base agent is not particularly limited, and can be formed by a conventionally known method.
For example, the layer 12 made of the base agent can be formed by applying the base agent onto the substrate 11 by a conventionally known method such as spin coating or using a spinner to form a coating film and drying it. Details of the base agent will be described later.
As a method for drying the coating film, it is sufficient if the organic solvent contained in the base material can be volatilized, and examples thereof include a baking method.
The baking temperature is preferably 80 to 300 ° C, more preferably 100 to 270 ° C, and further preferably 120 to 250 ° C. The baking time is preferably 30 to 500 seconds, and more preferably 60 to 240 seconds.
By providing the base material layer 12 on the surface of the substrate 11, the surface of the substrate 11 is neutralized, and among the layer 13 made of a block copolymer provided on the upper layer, only the phase made of a specific block is in contact with the substrate surface. Can be suppressed. As a result, it is possible to form a cylinder structure, a lamellar structure, a dot structure, a gyroid structure, a spherical dispersion structure, or the like that is freely oriented with respect to the substrate surface by phase separation of the layer 13 containing the block copolymer.

[Process for forming a resist pattern by applying a resist composition that generates acid upon exposure and changes its solubility in a developing solution by the action of an acid on a layer comprising a base material]
In the present invention, after [the step of applying the base agent on the substrate and forming a layer made of the base agent], an acid is generated by exposure on the layer 12 made of the base agent, and the acid The resist pattern 14 is formed by applying a resist composition whose solubility in the developing solution is changed by the action.

  Specifically, first, a resist composition to be described later is applied onto the layer 12 made of the base agent with a spinner or the like, and baking (post-apply bake (PAB)) treatment is performed at a temperature condition of 80 to 150 ° C. A resist film is formed by applying for 120 seconds, preferably 60 to 90 seconds.

  Next, the resist film is exposed through a mask (mask pattern) on which a predetermined pattern is formed using an exposure apparatus such as an ArF exposure apparatus, an electron beam drawing apparatus, or an EUV exposure apparatus, or a mask pattern. After performing selective exposure by drawing or the like by direct irradiation with an electron beam without passing through, baking (post-exposure baking (PEB)) treatment is performed, for example, at a temperature of 80 to 150 ° C. for 40 to 120 seconds, preferably 60 Apply for ~ 90 seconds.

The wavelength used for the exposure is not particularly limited, and ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. Can be done using radiation. The resist composition is highly useful for KrF excimer laser, ArF excimer laser, EB or EUV.

The exposure method of the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or may be immersion exposure (Liquid Immersion Lithography).
In immersion exposure, the space between the resist film and the lens at the lowest position of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than that of air, and exposure (immersion exposure) is performed in that state. It is an exposure method.
As the immersion medium, a solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film to be exposed is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.
Examples of the solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent.
Specific examples of the fluorine-based inert liquid include a fluorine-based compound such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as a main component. Examples thereof include liquids, and those having a boiling point of 70 to 180 ° C are preferable, and those having a boiling point of 80 to 160 ° C are more preferable. It is preferable that the fluorine-based inert liquid has a boiling point in the above range since the medium used for immersion can be removed by a simple method after the exposure is completed.
As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.
More specifically, examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point: 102 ° C.). Examples of the perfluoroalkylamine compound include perfluorotributylamine ( Boiling point of 174 ° C.).
As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility, and the like.
Next, the resist film is developed.

After the step, the resist film is developed to form a resist pattern 14.
The development treatment is performed using an alkaline developer in the case of an alkali development process, and using a developer (organic developer) containing an organic solvent in the case of a solvent development process.
A rinsing treatment is preferably performed after the development treatment. The rinse treatment is preferably a water rinse using pure water in the case of an alkali development process, and is preferably a rinse solution containing an organic solvent in the case of a solvent development process.
In the case of a solvent development process, after the development process or the rinse process, a process of removing the developer or rinse liquid adhering to the pattern with a supercritical fluid may be performed.
Drying is performed after development or rinsing. In the present invention, it is preferable to perform a baking process (post baking) after the development process.

Examples of the alkali developer used for the development treatment in the alkali development process include 0.1 to 10% by mass tetramethylammonium hydroxide (TMAH) aqueous solution.
The organic solvent contained in the organic developer used for the development process in the solvent development process is not particularly limited as long as it can dissolve the component (A) (component (A) before exposure). It can be selected as appropriate. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents can be used.
A known additive can be blended in the organic developer as required. Examples of the additive include a surfactant. The surfactant is not particularly limited. For example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used.
When the surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0. 5 mass% is more preferable.

  The development process can be performed by a known development method. For example, a method in which a support is immersed in a developer for a certain period of time (dip method), a developer is raised on the surface of the support by surface tension, and is left for a certain period of time. (Paddle method), spraying developer on the surface of the support (spray method), coating the developer while scanning the developer coating nozzle at a constant speed on the support rotating at a constant speed The method to continue (dynamic dispensing method) etc. are mentioned.

  The rinse treatment (washing treatment) using the rinse liquid can be performed by a known rinse method. Examples of the method include a method of continuously applying a rinsing liquid on a support rotating at a constant speed (rotary coating method), a method of immersing the support in a rinsing liquid for a predetermined time (dip method), and the surface of the support. And a method of spraying a rinse liquid (spray method).

[Step of forming a layer containing a block copolymer in which a plurality of types of blocks are bonded on the layer made of the base agent on which the resist pattern is formed]
First, the layer 13 containing a block copolymer is formed on the substrate surface. Specifically, a block copolymer dissolved in an applicable organic solvent is applied to the surface of the substrate 11 on which the layer 12 and the layer 14 made of a base agent are formed using a spinner or the like.
The organic solvent for dissolving the block copolymer will be described later.

The thickness of the layer 13 containing the block copolymer formed on the substrate surface depends on the molecular weight (polymer cycle) of the block copolymer, and is generally applied in the range of 0.5 to 4.0 times the polymer cycle.
In the present invention, the thickness of the layer 13 containing the block copolymer may be sufficient to cause phase separation, and the lower limit of the thickness is not particularly limited, but the strength of the nanostructure, the nanostructure Considering the uniformity of the substrate on which the body is formed, it is preferably 3 nm or more, more preferably 5 nm or more.

<Block copolymer>
Block copolymer In the present invention, the block copolymer is a polymer in which a plurality of partial constituent components (blocks) in which only structural units of the same kind are bonded. There may be two types of blocks constituting the block copolymer, or three or more types. In the present invention, the plural types of blocks constituting the block copolymer are not particularly limited as long as they are combinations in which phase separation occurs, but are preferably combinations of blocks that are incompatible with each other. Moreover, it is preferable that the phase which consists of at least 1 type block in the multiple types of block which comprises a block copolymer is a combination which can be selectively removed easily rather than the phase which consists of other types of block.

Examples of block copolymers include:
A block copolymer in which a block of structural units derived from styrene or a derivative thereof and a block of structural units derived from an (α-substituted) acrylate ester are combined;
A block copolymer obtained by combining a block of a structural unit derived from styrene or a derivative thereof and a block of a structural unit derived from siloxane or a derivative thereof;
-A block copolymer in which a block of a structural unit derived from an alkylene oxide and a block of a structural unit derived from an (α-substituted) acrylate ester are combined.

The structural unit derived from styrene or a derivative thereof and the structural unit derived from an (α-substituted) acrylate ester are the same as described above.
Examples of the siloxane derivative include dimethylsiloxane, diethylsiloxane, diphenylsiloxane, methylphenylsiloxane, and the like.
Examples of the alkylene oxide include ethylene oxide, propylene oxide, isopropylene oxide, and butylene oxide.

Among these, as the block copolymer, it is preferable to use a block copolymer obtained by bonding a block of a structural unit derived from styrene or a derivative thereof and a block of a structural unit derived from a (meth) acrylate ester.
Specifically, polystyrene-polymethyl methacrylate (PS-PMMA) block copolymer, polystyrene-polyethyl methacrylate block copolymer, polystyrene- (poly-t-butyl methacrylate) block copolymer, polystyrene-polymethacrylic acid block copolymer, polystyrene-poly. Examples thereof include a methyl acrylate block copolymer, a polystyrene-polyethyl acrylate block copolymer, a polystyrene- (poly-t-butyl acrylate) block copolymer, a polystyrene-polyacrylic acid block copolymer, and it is particularly preferable to use a PS-PMMA block copolymer. .

The mass average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of each polymer constituting the block copolymer is not particularly limited as long as it is a size capable of causing phase separation. To 50,000,000 are preferable, 5,000 to 400,000 are more preferable, and 5,000 to 300,000 are more preferable.
Further, the dispersity (Mw / Mn) of the block copolymer is preferably 1.0 to 3.0, more preferably 1.0 to 1.5, and still more preferably 1.0 to 1.2. In addition, Mn shows a number average molecular weight.

  In addition to the above-mentioned block copolymer, the composition containing the block copolymer further improves, if desired, an additive resin for improving the performance of a layer made of a miscible additive, for example, a base agent, and coatability. Surfactants, dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, dyes, sensitizers, base proliferating agents, basic compounds, and the like can be appropriately added and contained.

-Organic solvent The composition containing a block copolymer can be prepared by dissolving the block copolymer in an organic solvent. Any organic solvent may be used as long as it can dissolve each component to be used to form a uniform solution. Conventionally, an arbitrary solvent can be selected from among known solvents for resin-based film compositions. One or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; Monohydric alcohols; compounds having an ester bond, such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl of the polyhydric alcohols or compound having the ester bond Ether alkyl such as ether, monopropyl ether, monobutyl ether or monophenyl ether Derivatives of polyhydric alcohols such as compounds having a propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME) among these]; cyclic ethers such as dioxane, methyl lactate, Esters such as ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, Aromatic organics such as dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene A solvent etc. can be mentioned.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range. For example, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3. When PGME and cyclohexanone are blended as polar solvents, the mass ratio of PGMEA: (PGME + cyclohexanone) is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, and still more preferably 3. : 7 to 7: 3.

In addition, as the organic solvent in the composition containing the block copolymer, PGMEA, EL, or a mixed solvent of PGMEA and a polar solvent and a mixed solvent of γ-butyrolactone are also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of the organic solvent used in the composition containing the block copolymer is not particularly limited, and can be appropriately set according to the coating film thickness at a coatable concentration. Is used in such a manner that the solid content concentration is 0.2 to 70% by mass, preferably 0.2 to 50% by mass.

In the following, among the blocks constituting the block copolymer, after the block P _A blocks not be selectively removed in step, the blocks are selectively removed as P _B block. For example, after phase-separating a layer containing PS-PMMA block copolymer, a phase composed of PMMA is selectively removed by performing oxygen plasma treatment, hydrogen plasma treatment, or the like on the layer. In this case, PS is a block _{P A,} PMMA is _{P B} block.

In the present invention, phase is selectively removed (i.e., P _B of blocks phase 4a) shape and size of the component ratio or the blocks constituting the block copolymer is defined by the molecular weight of the block copolymer. For example, by a relatively small component ratio per volume of the block P _B occupied in the block copolymer, forming a cylindrical structure phase 4a made of block P _B into phase 13b consisting of P _A block is present in the cylindrical Can be made. On the other hand, by the component ratio per volume of the block P _B and P _A block occupied in the block copolymer to the same extent, and the phase 4a of phase 4b and P _B block consisting of block P _A stacked alternately A lamellar structure can be formed. In addition, the size of each phase can be increased by increasing the molecular weight of the block copolymer.

[Step of phase-separating the layer containing the block copolymer on the pattern and the neutralized film]
In the present invention, after the step (a step of forming a layer including a block copolymer in which a plurality of types of polymers are bonded so as to cover the pattern and the neutralized film on the pattern), a layer 13 including a block copolymer is formed. Phase separate.

The phase separation of the layer 13 containing the block copolymer is performed after the layer 13 containing the block copolymer is formed, thereby forming a phase separation structure. The temperature of the heat treatment is preferably higher than the glass transition temperature of the layer containing the block copolymer to be used and lower than the thermal decomposition temperature. For example, when the block copolymer is PS-PMMA (Mw: 18k-18k), heat treatment is preferably performed at 160 to 270 ° C. for 30 to 3600 seconds.
The heat treatment is preferably performed in a gas having low reactivity such as nitrogen.

[Step of selectively removing a phase composed of at least one block out of a plurality of types of blocks constituting the block copolymer in the layer containing the block copolymer]
A pattern is formed by selectively removing the phase 13a composed of at least one block among a plurality of types of blocks constituting the block copolymer in the layer 13 containing the block copolymer.
Specifically, the phase of the layers 13 containing the block copolymer on a substrate after the separation structure was formed, to selectively remove at least some of the blocks of the phase in consisting of block P _B (low molecular weight) . By pre selectively removing portions of the block P _B, results enhanced dissolution in a developer, tends to selectively remove than the phase 13b to phase 13a consisting of block P _B is formed of a block P _A .

Such selective removal process does not affect relative block P _A, if a process capable of decomposing and removing the block P _B, is not particularly limited, the technique used for the removal of the resin film from within, according to the type of block P _a and P _B block can be performed appropriately selected. Also, when the pre-neutralization film is formed on the substrate surface, the neutralization film is also removed as well as phase consisting block P _B. Examples of such removal treatment include oxygen plasma treatment, ozone treatment, UV irradiation treatment, thermal decomposition treatment, and chemical decomposition treatment.

  Although the substrate on which the pattern 13b is formed by phase separation of the layer 13 made of the block copolymer as described above can be used as it is, the shape of the polymer nanostructure on the substrate can be changed by further heat treatment. It can also be changed. The temperature of the heat treatment is preferably higher than the glass transition temperature of the block copolymer used and lower than the thermal decomposition temperature. The heat treatment is preferably performed in a gas having low reactivity such as nitrogen.

<< Pattern Formation Method 2 >>
In the third aspect of the present invention, a step of applying the base agent on a substrate to form a layer made of the base agent, and then a plurality of types of polymers are bonded on the layer made of the base agent. A pattern forming method comprising: a step of forming a layer containing the block copolymer; and a step of phase-separating the layer containing the block copolymer. Hereinafter, the pattern forming method 2 of the present invention will be specifically described with reference to FIG. However, the present invention is not limited to this.

[Step of applying a base agent and forming a layer comprising the base agent]
In the present invention, first, the base material of the first aspect of the present invention is applied on the substrate 1 to form the layer 2 made of the base material. The explanation about the substrate 1 and the explanation of the coating method of the base material 2 are the same as the explanation in << Pattern Forming Method 1 >>.

[Step of forming a layer containing a block copolymer in which a plurality of types of polymers are bonded on a layer made of a base material]
In the present invention, a layer 3 containing a block copolymer is formed on the layer 2 made of a base agent. The explanation about the block copolymer and the coating method thereof is the same as the explanation in << Pattern Forming Method 1 >>.

[Step of phase-separating layer containing block copolymer]
In the present invention, after the above step, the layer 3 containing the block copolymer is phase-separated into phase 3a and phase 3b. The explanation about the phase separation is the same as the explanation in << Pattern Forming Method 1 >>.

<Optional process>
In the pattern forming method 2 described above, after the step of phase-separating the layer containing the block copolymer, among the layers containing the block copolymer, the pattern forming method 2 includes at least one kind of blocks among the plurality of types of blocks constituting the block copolymer. The phase may be selectively removed.
Specifically, the pattern can be formed by removing the phase 3a including the block copolymer on the substrate after forming the phase separation structure. The description of such a selective removal process is the same as that described in << Pattern Forming Method 1 >>.

<Resist composition>
In the present invention, the resist composition is a resist composition that generates an acid upon exposure and changes its solubility in a developer by the action of an acid, and is a base material component whose solubility in a developer changes by the action of an acid (A) (hereinafter also referred to as “component (A)”) is preferably contained.
When a resist film is formed using such a resist composition and the resist film is selectively exposed, an acid is generated in the exposed portion, and the action of the acid causes the solubility of the component (A) in the developer. On the other hand, since the solubility of the component (A) in the developer does not change in the unexposed area, a difference in solubility in the developer occurs between the exposed and unexposed areas. Therefore, when the resist film is developed, when the resist composition is positive, the exposed portion is dissolved and removed to form a positive resist pattern, and when the resist composition is negative, the unexposed portion is dissolved. This is removed to form a negative resist pattern.
In this specification, a resist composition in which an exposed portion is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition that forms a negative resist pattern in which an unexposed portion is dissolved and removed. Is referred to as a negative resist composition.
In the present invention, the resist composition may be a positive resist composition or a negative resist composition.
In the present invention, the resist composition may be used for an alkali development process using an alkali developer for the development process at the time of forming a resist pattern, and a developer (organic developer) containing an organic solvent in the development process. It may be for a solvent development process using

In the present invention, the resist composition has an acid generating ability to generate an acid upon exposure, and the (A) component may generate an acid upon exposure, and is added separately from the (A) component. The agent component may generate an acid upon exposure.
Specifically, in the present invention, the resist composition is
(1) It may contain an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as “component (B)”);
(2) The component (A) may be a component that generates an acid upon exposure;
(3) The component (A) is a component that generates an acid upon exposure, and may further contain a component (B).
That is, in the case of the above (2) and (3), the component (A) is a “base material component that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid”. When the component (A) is a base material component that generates an acid upon exposure and changes its solubility in a developer due to the action of the acid, the component (A1) described later generates an acid upon exposure, and A polymer compound whose solubility in a developing solution is changed by the action of an acid is preferable. As such a polymer compound, a resin having a structural unit that generates an acid upon exposure can be used. A well-known thing can be used as a structural unit which generate | occur | produces an acid by exposure.
In the present invention, the resist composition is particularly preferably the case (1).

<(A) component>
In the present invention, the “base component” is an organic compound having a film forming ability, and preferably an organic compound having a molecular weight of 500 or more is used. When the molecular weight of the organic compound is 500 or more, the film forming ability is improved, and in addition, a nano-level resist pattern is easily formed.
Organic compounds used as the base material component are roughly classified into non-polymers and polymers.
As the non-polymer, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, the “low molecular compound” refers to a non-polymer having a molecular weight of 500 or more and less than 4000.
As the polymer, those having a molecular weight of 1000 or more are usually used. Hereinafter, the term “resin” refers to a polymer having a molecular weight of 1000 or more.
As the molecular weight of the polymer, a polystyrene-reduced weight average molecular weight by GPC (gel permeation chromatography) is used.
As the component (A), a resin may be used, a low molecular compound may be used, or these may be used in combination.
Component (A) may have increased solubility in a developer due to the action of an acid, or may decrease solubility in a developer due to the action of an acid.
In the present invention, the component (A) may generate an acid upon exposure.

In the present invention, the component (A) is a structural unit containing an acid-decomposable group whose polarity is increased by the action of an acid (hereinafter sometimes referred to as “structural unit (a1)”), a —SO ₂ -containing cyclic group. A structural unit derived from an acrylate ester containing a group (hereinafter sometimes referred to as “structural unit (a2)”), a structural unit containing a polar group-containing aliphatic hydrocarbon group (hereinafter referred to as “structural unit (a3)”) ), A structural unit containing a non-acid-dissociable cyclic group (hereinafter sometimes referred to as “structural unit (a4)”) and a lactone-containing cyclic group or a carbonate-containing cyclic group The polymer compound (A1) having a unit (hereinafter sometimes referred to as “structural unit (a5)”) is preferably included.

(Structural unit (a1))
The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity is increased by the action of an acid.
The “acid-decomposable group” is an acid-decomposable group that can cleave at least part of bonds in the structure of the acid-decomposable group by the action of an acid.
Examples of the acid-decomposable group whose polarity increases by the action of an acid include a group that decomposes by the action of an acid to generate a polar group.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, a sulfo group (—SO ₃ H), and the like. Among these, a polar group containing —OH in the structure (hereinafter sometimes referred to as “OH-containing polar group”) is preferable, a carboxy group or a hydroxyl group is preferable, and a carboxy group is particularly preferable.
More specifically, examples of the acid-decomposable group include groups in which the polar group is protected with an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).
Here, “acid-dissociable group” means
(I) an acid-dissociable group capable of cleaving a bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group by the action of an acid, or
(Ii) a group capable of cleaving a bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group by further decarboxylation reaction after partial bond cleavage by the action of an acid ,
Both.
The acid-dissociable group constituting the acid-decomposable group must be a group having a lower polarity than the polar group generated by dissociation of the acid-dissociable group. Is dissociated, a polar group having a polarity higher than that of the acid dissociable group is generated to increase the polarity. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developer changes relatively, and when the developer is an organic developer, the solubility decreases.

The acid-dissociable group is not particularly limited, and those that have been proposed as acid-dissociable groups for base resins for chemically amplified resists can be used.
Among the polar groups, examples of the acid dissociable group that protects a carboxy group or a hydroxyl group include an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter referred to as “acetal acid dissociable for convenience”). Group ”).

［式中、Ｒａ’^１、Ｒａ’^２は水素原子またはアルキル基、Ｒａ’^３は炭化水素基、Ｒａ’^３は、Ｒａ’^１、Ｒａ’^２のいずれかと結合して環を形成してもよい。］

[Wherein, Ra ′ ¹ and Ra ′ ² are hydrogen atoms or alkyl groups, Ra ′ ³ is a hydrocarbon group, and Ra ′ ³ may be bonded to either Ra ′ ¹ or Ra ′ ² to form a ring. Good. ]

In formula (a1-r-1), Ra ′ ¹ and Ra ′ ² are exemplified as the substituents that may be bonded to the α-position carbon atom in the description of the α-substituted acrylate ester. Examples thereof include the same as the alkyl group, preferably a methyl group or an ethyl group, and most preferably a methyl group.

The hydrocarbon group for Ra ′ ³ is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms; a linear or branched alkyl group is preferable, specifically , Methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, 1,1-dimethylethyl group, 1,1-diethylpropyl group 2,2-dimethylpropyl group, 2,2, -dimethylbutyl group and the like can be mentioned.

When Ra ′ ³ is a cyclic hydrocarbon group, it may be aliphatic or aromatic, may be polycyclic, or may be monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane preferably has 3 to 8 carbon atoms, and specific examples include cyclopentane, cyclohexane and cyclooctane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

In the case of an aromatic hydrocarbon group, specific examples of the aromatic ring contained include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene; carbon atoms constituting the aromatic hydrocarbon ring. An aromatic heterocycle partially substituted with a heteroatom; and the like. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon group is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group); a group in which one of the hydrogen atoms of the aryl group is substituted with an alkylene group (for example, Benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, arylalkyl group such as 2-naphthylethyl group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

When Ra ′ ³ is bonded to either Ra ′ ¹ or Ra ′ ² to form a ring, the cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

  Among the polar groups, examples of the acid dissociable group that protects the carboxy group include an acid dissociable group represented by the following general formula (a1-r-2) (the following formula (a1-r-2) Among the acid dissociable groups represented by), those composed of an alkyl group may hereinafter be referred to as “tertiary alkyl ester type acid dissociable groups” for convenience).

［式中、Ｒａ’^４〜Ｒａ’^６は炭化水素基であり、Ｒａ’^５、Ｒａ’^６は互いに結合して環を形成してもよい。］

[Wherein, Ra ′ ^{4 to} Ra ′ ⁶ are hydrocarbon groups, and Ra ′ ⁵ and Ra ′ ⁶ may be bonded to each other to form a ring. ]

As the hydrocarbon group for Ra ′ ^{4 to} Ra ′ ^6, the same groups as those described above for Ra ′ ³ can be mentioned. Ra ′ ⁴ is preferably an alkyl group having 1 to 5 carbon atoms. In the case where Ra ′ ⁵ and Ra ′ ⁶ are bonded to each other to form a ring, a group represented by general formula (a1-r2-1) shown below can be given.
On the other hand, when Ra ′ ^{4 to} Ra ′ ⁶ are not bonded to each other and are independent hydrocarbon groups, groups represented by the following general formula (a1-r2-2) are exemplified.

［式中、Ｒａ’^１０は炭素数１〜１０のアルキル基、Ｒａ’^１１はＲａ’^１０が結合した炭素原子と共に脂肪族環式基を形成する基、Ｒａ’^１２〜Ｒａ’^１４は、それぞれ独立に炭化水素基を示す。］

[Wherein, Ra ′ ¹⁰ is an alkyl group having 1 to ¹⁰ carbon atoms, Ra ′ ¹¹ is a group that forms an aliphatic cyclic group together with a carbon atom to which Ra ′ ¹⁰ is bonded, and Ra ′ ^{12 to} Ra ′ ¹⁴ are Independently represents a hydrocarbon group. ]

In formula (a1-r2-1), the alkyl group of the alkyl group having 1 to ¹⁰ carbon atoms of Ra ′ ¹⁰ is a linear or branched alkyl group of Ra ′ ³ in formula (a1-r-1) The groups mentioned as are preferred. Wherein (a1-r2-1), Ra 'aliphatic cyclic ^{group 11} is configured, Ra in formula (a1-r-1)' group listed as a cyclic alkyl group of ³ is preferred.

In formula (a1-r2-2), Ra ′ ¹² and Ra ′ ¹⁴ are preferably each independently an alkyl group having 1 to 10 carbon atoms, and the alkyl group is represented by Ra in formula (a1-r-1). 'The group mentioned as a linear or branched alkyl group of ³ is more preferable, It is more preferable that it is a C1-C5 linear alkyl group, It is especially preferable that it is a methyl group or an ethyl group .
In formula (a1-r2-2), Ra ′ ¹³ is a linear, branched or cyclic alkyl group exemplified as the hydrocarbon group for Ra ′ ³ in formula (a1-r-1). Is preferred. Among these, a group exemplified as the cyclic alkyl group for Ra ′ ³ is more preferable.

  Specific examples of the formula (a1-r2-1) are given below. In the following formula, “*” indicates a bond.

  Specific examples of the formula (a1-r2-2) are given below.

  Examples of the acid dissociable group for protecting the hydroxyl group among the polar groups include, for example, an acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as “tertiary alkyloxycarbonyl acid for convenience”). Sometimes referred to as a “dissociable group”).

［式中、Ｒａ’^７〜Ｒａ’^９はアルキル基を示す。］

[Wherein, Ra ′ ^{7 to} Ra ′ ⁹ represent an alkyl group. ]

In formula (a1-r-3), Ra ′ ^{7 to} Ra ′ ⁹ are preferably an alkyl group having 1 to 5 carbon atoms, and more preferably 1 to 3 groups.
Moreover, it is preferable that the total carbon number of each alkyl group is 3-7, it is more preferable that it is 3-5, and it is most preferable that it is 3-4.

  The structural unit (a1) is a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and an acid whose polarity is increased by the action of an acid. A structural unit containing a decomposable group; a structural unit in which at least a part of hydrogen atoms in the hydroxyl group of a structural unit derived from hydroxystyrene or a hydroxystyrene derivative is protected by a substituent containing the acid-decomposable group; vinylbenzoic acid or Examples include a structural unit in which at least a part of hydrogen atoms in —C (═O) —OH of a structural unit derived from a vinylbenzoic acid derivative is protected by a substituent containing the acid-decomposable group.

Among the above, the structural unit (a1) is preferably a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent.
As the structural unit (a1), structural units represented by general formula (a1-1) or (a1-2) shown below are preferred.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。Ｖａ^１はエーテル結合、ウレタン結合、又はアミド結合を有していてもよい２価の炭化水素基であり、ｎ_ａ１は０〜２であり、
Ｒａ^１は上記式（ａ１−ｒ−１）〜（ａ１−ｒ−２）で表される酸解離性基である。
Ｗａ^１はｎ_ａ２＋１価の炭化水素基であり、ｎ_ａ２は１〜３であり、
Ｒａ^２は上記式（ａ１−ｒ−１）または（ａ１−ｒ−３）で表される酸解離性基である。］

[Wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group which may have an ether bond, a urethane bond, or an amide bond, _na1 is 0 to 2,
Ra ¹ is an acid dissociable group represented by the above formulas (a1-r-1) to (a1-r-2).
Wa ¹ is n _a2 +1 valent hydrocarbon group, n _a2 is 1 to 3,
Ra ² is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-3). ]

In the general formula (a1-1), the alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically, a methyl group, an ethyl group, Examples include propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and is most preferably a hydrogen atom or a methyl group in terms of industrial availability.
The hydrocarbon group for Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group as a divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is usually preferably saturated.
Specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in the structure, and the like.
Examples of Va ¹ include those in which the divalent hydrocarbon group is bonded through an ether bond, a urethane bond, or an amide bond.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, more preferably 1 to 4, and most preferably 1 to 3.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group [—CH ₂ —], an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [ — (CH ₂ ) ₃ —], tetramethylene group [— (CH ₂ ) ₄ —], pentamethylene group [— (CH ₂ ) ₅ —] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ). _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as - _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH _{3) 2} -CH ₂ - alkyl groups such _{as; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such as; -CH _(CH 3) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group that is linear or branched. Examples thereof include a group bonded to the end of a chain aliphatic hydrocarbon group and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring.
The aromatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, and 6 to 6 carbon atoms. 15 is particularly preferable, and 6 to 10 is most preferable. However, the carbon number does not include the carbon number in the substituent.
Specific examples of the aromatic ring possessed by the aromatic hydrocarbon group include aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; some of the carbon atoms constituting the aromatic hydrocarbon ring are heterogeneous. Aromatic heterocycles substituted with atoms; and the like. Examples of the hetero atom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, the aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group) ) In which one of the hydrogen atoms is substituted with an alkylene group (for example, arylalkyl such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthylethyl, etc.) Group in which one hydrogen atom is further removed from the aryl group in the group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

In the formula (a1-2), the n _a2 +1 valent hydrocarbon group in Wa ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group including a ring in the structure, or a linear or branched aliphatic hydrocarbon group. It includes a group formed by combining an aliphatic hydrocarbon group in the structure containing a ring, and specific examples thereof include the same groups as Va ¹ of the aforementioned formula (a1-1).
The n _a2 +1 valence is preferably 2 to 4, and more preferably 2 or 3.

  As the formula (a1-2), a structural unit represented by general formula (a1-2-01) shown below is particularly desirable.

In formula (a1-2-01), Ra ² is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-3). n _a2 is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. c is an integer of 0 to 3, preferably 0 or 1, and more preferably 1. R is the same as described above.
Specific examples of the above formulas (a1-1) and (a1-2) are shown below. In the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

  The proportion of the structural unit (a1) in the component (A) is preferably from 20 to 80 mol%, more preferably from 20 to 75 mol%, more preferably from 25 to 70 mol%, based on all structural units constituting the component (A). Is more preferable. By setting the lower limit value or more, lithography properties such as sensitivity, resolution, and LWR are also improved. Moreover, the balance with another structural unit can be taken by making it below an upper limit.

(Structural unit (a2))
The structural unit (a2) is a structural unit containing a —SO ₂ — containing cyclic group.
The —SO ₂ — containing cyclic group of the structural unit (a2) is effective for enhancing the adhesion of the resist film to the substrate when the component (A1) is used for forming the resist film.
In addition, when the structural unit (a1) includes a —SO ₂ — containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a2). It corresponds to a1) and does not correspond to the structural unit (a2).

  The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｙａ^２１は単結合または２価の連結基であり、Ｌａ^２１は−Ｏ−、−ＣＯＯ−、−ＣＯＮ（Ｒ’）−、−ＯＣＯ−、−ＣＯＮＨＣＯ−又は−ＣＯＮＨＣＳ−であり、Ｒ’は水素原子またはメチル基を示す。ただしＬａ^２１が−Ｏ−の場合、Ｙａ^２１は−ＣＯ−にはならない。Ｒａ^２１は−ＳＯ_２−含有環式基である。］

[Wherein, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, Ya ²¹ is a single bond or a divalent linking group, and La ²¹ is —O -, -COO-, -CON (R ')-, -OCO-, -CONHCO- or -CONHCS-, wherein R' represents a hydrogen atom or a methyl group. However, when La ²¹ is —O—, Ya ²¹ is not —CO—. Ra ²¹ is a —SO ₂ — containing cyclic group. ]

The divalent linking group of Ya ²¹ is not particularly limited, and preferred examples thereof include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom.

(Divalent hydrocarbon group which may have a substituent)
The hydrocarbon group as the divalent linking group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like. Specifically, the above-described formula (a1- The group illustrated by Va ¹ in 1) is mentioned.

  The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (excluding two hydrogen atoms from the aliphatic hydrocarbon ring) Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is a linear or branched chain fatty acid. Group intervening in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include those described above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
Specific examples of the cyclic aliphatic hydrocarbon group include the groups exemplified for Va ¹ in the above formula (a1-1).
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Most preferred is an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. As the substituent containing the hetero atom, —O—, —C (═O) —O—, —S—, —S (═O) ₂ —, and —S (═O) ₂ —O— are preferable.

Specific examples of the aromatic hydrocarbon group as the divalent hydrocarbon group include groups exemplified by Va ¹ in the above formula (a1-1).
In the aromatic hydrocarbon group, a hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the alkoxy group, the halogen atom and the halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

(Divalent linking group containing a hetero atom)
The hetero atom in the divalent linking group containing a hetero atom is an atom other than a carbon atom and a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom.

When Ya ²¹ is a divalent linking group containing a hetero atom, preferred examples of the linking group include —O—, —C (═O) —O—, —C (═O) —, and —O—C. (═O) —O—, —C (═O) —NH—, —NH—, —NH—C (═NH) — (H may be substituted with a substituent such as an alkyl group or an acyl group). _{.), - S -, -} S (= O) 2 -, - S (= O) 2 -O-, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 - C (═O) —O—, —C (═O) —O—Y ²¹ , [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (= O) a group represented by —Y ²² —, wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, m 'is an integer of 0-3. ] Etc. are mentioned.
When the divalent linking group containing a hetero atom is —C (═O) —NH—, —NH—, —NH—C (═NH) —, H is a substituent such as an alkyl group or acyl. May be substituted. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - C (= O) -O - Y 21, - [Y 21 -C (═O) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (═O) —Y ²² —, wherein Y ²¹ and Y ²² each independently have a substituent. It is also a good divalent hydrocarbon group. Examples of the divalent hydrocarbon group include those similar to the “divalent hydrocarbon group optionally having substituent (s)” mentioned in the description of the divalent linking group.
Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group. preferable.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, and more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² —, m ′ is an integer of 0 to 3, preferably an integer of 0 to 2, Or 1 is more preferable, and 1 is particularly preferable. That is, the group represented by the formula — [Y ²¹ —C (═O) —O] _{m ′} —Y ²² — is represented by the formula —Y ²¹ —C (═O) —O—Y ²² —. The group is particularly preferred. Among these, a group represented by the formula — (CH ₂ ) _{a ′} —C (═O) —O— (CH ₂ ) _{b ′} — is preferable. In the formula, a ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1.

In the present invention, Ya ²¹ is a single bond, an ester bond [—C (═O) —O—], an ether bond (—O—), a linear or branched alkylene group, or a combination thereof. Preferably there is.

In the formula (a2-1), Ra ²¹ is a —SO ₂ — containing cyclic group.

The “—SO ₂ -containing cyclic group” refers to a cyclic group containing a ring containing —SO ₂ — in the ring skeleton, specifically, the sulfur atom (S) in —SO ₂ — is It is a cyclic group that forms part of the ring skeleton of the cyclic group. The ring containing —SO ₂ — in the ring skeleton is counted as the first ring, and when it is only the ring, it is a monocyclic group, and when it has another ring structure, it is a polycyclic group regardless of the structure. Called. The —SO ₂ — containing cyclic group may be monocyclic or polycyclic.
The —SO ₂ — containing cyclic group as the cyclic hydrocarbon group in R ¹ is particularly a cyclic group containing —O—SO ₂ — in its ring skeleton, that is, —O— in —O—SO ₂ —. -S- is preferably a cyclic group containing a sultone ring that forms part of the ring skeleton. More specifically, examples of the —SO ₂ -containing cyclic group include groups represented by the following general formulas (a5-r-1) to (a5-r-4).

［式中、Ｒａ’^５１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０〜２の整数である。］

[Wherein, Ra ′ ⁵¹ independently represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group. Yes; R ″ is a hydrogen atom or an alkyl group; A ″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n ′ is 0 to 2 Is an integer. ]

In the general formulas (a5-r-1) to (a5-r-4), A ″ is the same as A ″ in the general formulas (a2-r-1) to (a2-r-7). As the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in Ra ′ ⁵¹ , the above general formulas (a2-r-1) to (a2 The same as Ra ′ ²¹ in −r-7).

  Specific examples of groups represented by general formulas (a5-r-1) to (a5-r-4) are given below. “Ac” in the formula represents an acetyl group.

As the —SO ₂ — containing cyclic group, among the above, a group represented by the general formula (a5-r-1) is preferable, and the chemical formulas (r-sl-1-1) and (r-sl— It is more preferable to use at least one selected from the group consisting of groups represented by any one of 1-18), (r-sl-3-1) and (r-sl-4-1), The group represented by (r-sl-1-1) is most preferable.

The structural unit (a2) contained in the component (A1) may be one type or two or more types.
When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 1 to 80 mol% with respect to the total of all the structural units constituting the component (A1). It is more preferably 5 to 70 mol%, further preferably 10 to 65 mol%, and particularly preferably 10 to 60 mol%. By making it the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by making it the upper limit value or less, it is possible to balance with other structural units, and various lithography characteristics and patterns Good shape.

(Structural unit (a3))
The structural unit (a3) is a structural unit containing a polar group-containing aliphatic hydrocarbon group (except for those corresponding to the structural units (a1) and (a2) described above).
It is considered that when the component (A1) has the structural unit (a3), the hydrophilicity of the component (A) is increased and the resolution is improved.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group is substituted with a fluorine atom. A hydroxyl group is particularly preferable.
Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group. For example, a resin for a resist composition for an ArF excimer laser can be appropriately selected from those proposed. The cyclic group is preferably a polycyclic group, and more preferably 7 to 30 carbon atoms.
Among them, a structural unit derived from an acrylate ester containing an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of hydrogen atoms of a hydroxyl group, a cyano group, a carboxy group, or an alkyl group is substituted with a fluorine atom Is more preferable. Examples of the polycyclic group include groups in which two or more hydrogen atoms have been removed from bicycloalkane, tricycloalkane, tetracycloalkane and the like. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane. Industrially preferable.

The structural unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any structural unit can be used.
The structural unit (a3) is a structural unit derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and includes a polar group-containing aliphatic hydrocarbon group A structural unit is preferred.
The structural unit (a3) is derived from a hydroxyethyl ester of acrylic acid when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms. When the hydrocarbon group is a polycyclic group, the structural unit represented by the following formula (a3-1), the structural unit represented by the formula (a3-2), the formula ( The structural unit represented by a3-3) is preferred.

［式中、Ｒは前記と同じであり、ｊは１〜３の整数であり、ｋは１〜３の整数であり、ｔ’は１〜３の整数であり、ｌは１〜５の整数であり、ｓは１〜３の整数である。］

[Wherein, R is the same as above, j is an integer of 1 to 3, k is an integer of 1 to 3, t ′ is an integer of 1 to 3, and l is an integer of 1 to 5] And s is an integer of 1 to 3. ]

In formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.
j is preferably 1, and it is particularly preferred that the hydroxyl group is bonded to the 3-position of the adamantyl group.

In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.
In formula (a3-3), t ′ is preferably 1. l is preferably 1. s is preferably 1. In these, a 2-norbornyl group or a 3-norbornyl group is preferably bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5th or 6th position of the norbornyl group.

As the structural unit (a3) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
In the component (A1), the proportion of the structural unit (a3) is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, based on the total of all structural units constituting the resin component (A1). Preferably, 5 to 25 mol% is more preferable.
By setting the proportion of the structural unit (a3) to the lower limit value or more, the effect of including the structural unit (a3) can be sufficiently obtained, and by setting the proportion of the structural unit (a3) to the upper limit value or less, balance with other structural units can be obtained. It becomes easy.

(Structural unit (a4))
The structural unit (a4) is a structural unit containing an acid non-dissociable cyclic group. When the component (A1) has the structural unit (a4), the dry etching resistance of the formed resist pattern is improved. Moreover, the hydrophobicity of (A1) component increases. The improvement in hydrophobicity is thought to contribute to the improvement of resolution, resist pattern shape, etc., particularly in the case of organic solvent development.
The “acid non-dissociable cyclic group” in the structural unit (a4) means that when an acid is generated from the later-described component (B) by exposure, it is not dissociated even if the acid acts on the structural unit. The remaining cyclic group.
As the structural unit (a4), for example, a structural unit derived from an acrylate ester containing a non-acid-dissociable aliphatic cyclic group is preferable. Examples of the cyclic group include those similar to those exemplified for the structural unit (a1), such as for ArF excimer laser, for KrF excimer laser (preferably for ArF excimer laser), etc. A number of hitherto known materials can be used as the resin component of the resist composition.
In particular, at least one selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group is preferable in terms of industrial availability. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.
Specific examples of the structural unit (a4) include those having the structures of the following general formulas (a4-1) to (a4-7).

［式中、Ｒ^αは、水素原子、メチル基またはトリフルオロメチル基を示す。］

[Wherein, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group. ]

As the structural unit (a4) contained in the component (A1), 1 type of structural unit may be used, or 2 or more types may be used.
When the structural unit (a4) is contained in the component (A1), the proportion of the structural unit (a4) is preferably 1 to 30 mol% with respect to the total of all the structural units constituting the component (A1). More preferably, it is 10-20 mol%.

(Structural unit (a5))
The structural unit (a5) is a structural unit containing a lactone-containing cyclic group or a carbonate-containing cyclic group.
The lactone-containing cyclic group or carbonate-containing cyclic group of the structural unit (a5) is effective in enhancing the adhesion of the resist film to the substrate when the component (A1) is used for forming the resist film. is there.
In addition, when the structural unit (a1) includes a lactone-containing cyclic group or a carbonate-containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a5). It corresponds to the structural unit (a1) and does not correspond to the structural unit (a5).

The structural unit (a5) is preferably a structural unit in which Ra ²¹ in the formula (a2-1) is a lactone-containing cyclic group or a carbonate-containing cyclic group.

  Examples of the “lactone-containing cyclic group” include the same groups as the “lactone-containing cyclic group” mentioned as the substrate interaction group that the component (A ′) may have.

The “carbonate-containing cyclic group” refers to a cyclic group containing a ring (carbonate ring) containing —O—C (═O) —O— in the ring skeleton. When the carbonate ring is counted as the first ring, the carbonate ring alone is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.
The carbonate ring-containing cyclic group as the cyclic hydrocarbon group for R ¹ is not particularly limited, and any one can be used. Specific examples include groups represented by the following general formulas (ax3-r-1) to (ax3-r-3).

［式中、Ｒａ’^ｘ３１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子でありｑ’は０または１である。］

[ ^Wherein , Ra ′ ^x31 each independently represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, —COOR ″, —OC (═O) R ″, a hydroxyalkyl group or a cyano group. Yes; R ″ is a hydrogen atom or an alkyl group; A ″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and q ′ is 0 or 1. is there. ]

In the general formulas (ax3-r-1) to (ax3-r-3), A ″ is the same as A ″ in the general formula (a2-r-1).
As the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, —COOR ″, —OC (═O) R ″, and hydroxyalkyl group in Ra ′ ³¹ , the above general formulas (a2-r-1) to ( a2-r-7) as in the same as those exemplified in the description of the Ra ^'21 of the like.

  Specific examples of groups represented by general formulas (ax3-r-1) to (ax3-r-3) are given below.

  Among them, the lactone-containing cyclic group is preferably a group represented by the general formula (a5-r-1), and includes the chemical formulas (r-sl-1-1) and (r-sl-1-18). ) Is more preferred.

The structural unit (a5) contained in the component (A1) may be one type or two or more types.
When the component (A1) has the structural unit (a5), the proportion of the structural unit (a5) is preferably 1 to 80 mol% with respect to the total of all the structural units constituting the component (A1). It is more preferably 5 to 70 mol%, further preferably 10 to 65 mol%, and particularly preferably 10 to 60 mol%. The effect by containing the structural unit (a5) can be sufficiently obtained by setting it to the lower limit value or more, and it can be balanced with other structural units by setting it to the upper limit value or less, and various kinds of DOF, CDU, etc. The lithography characteristics and pattern shape of the film are improved.

  The component (A1) is preferably a copolymer having any one of (a1), (a2), (a3), (a4) or (a5), the structural units (a1) and (a2), A copolymer having units (a1), (a2) and (a3) or structural units (a1), (a2), (a3) and (a5) is more preferred.

  In the present invention, the weight average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of the component (A1) is not particularly limited, preferably 1000 to 50000, more preferably 1500 to 30000, 2000 ˜20,000 is most preferred. If it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and if it is above the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.

As the component (A1), one type may be used alone, or two or more types may be used in combination.
The proportion of the component (A1) in the substrate component (A) is preferably 25% by mass or more, more preferably 50% by mass, even more preferably 75% by mass with respect to the total mass of the substrate component (A). It may be mass%. When the proportion is 25% by mass or more, the lithography properties are further improved.

In the resist composition of the present invention, as the component (A), one type may be used alone, or two or more types may be used in combination.
In the resist composition of the present invention, the content of the component (A) may be adjusted according to the resist film thickness to be formed.

  In the present invention, the resist composition may contain an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as the component (B)). The explanation about the component (B) is the same as the explanation about the acid generator (B) contained in the base agent.

<Basic compound component; (D) component>
In addition to the component (A) or the components (A) and (B), the resist composition of the present invention further includes an acid diffusion controller component (hereinafter also referred to as “component (D)”). You may contain.
The component (D) acts as a quencher (acid diffusion controller) that traps acid generated by exposure from the component (B) and the like.
The component (D) in the present invention may be a photodegradable base (D1) (hereinafter referred to as “(D1) component”) that is decomposed by exposure and loses acid diffusion controllability. A non-corresponding nitrogen-containing organic compound (D2) (hereinafter referred to as “component (D2)”) may be used.

[(D1) component]
By forming the resist composition containing the component (D1), the contrast between the exposed portion and the non-exposed portion can be improved when forming a resist pattern.
The component (D1) is not particularly limited as long as it is decomposed by exposure and loses acid diffusion controllability, and is a compound represented by the following general formula (d1-1) (hereinafter referred to as “(d1-1) component”). ), A compound represented by the following general formula (d1-2) (hereinafter referred to as “(d1-2) component”) and a compound represented by the following general formula (d1-3) (hereinafter referred to as “(d1- One or more compounds selected from the group consisting of “3) component”) are preferred.
The components (d1-1) to (d1-3) are decomposed in the exposed part and lose acid diffusion controllability (basicity), and therefore do not act as a quencher, and act as a quencher in an unexposed part.

［式中、Ｒｄ^１〜Ｒｄ^４は置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基である。ただし、式（ｄ１−２）中のＲｄ^２における、Ｓ原子に隣接する炭素原子にはフッ素原子は結合していないものとする。Ｙｄ^１は単結合、または２価の連結基である。Ｍ^ｍ＋はそれぞれ独立にｍ価の有機カチオンである。］

[Wherein Rd ^{1 to} Rd ⁴ are a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain which may have a substituent. Of the alkenyl group. However, a fluorine atom is not bonded to a carbon atom adjacent to the S atom in Rd ² in the formula (d1-2). Yd ¹ is a single bond or a divalent linking group. M ^{m +} is each independently an m-valent organic cation. ]

{(D1-1) component}
During Anion formula (d1-1), Rd ¹ is have an optionally substituted cyclic group which may have a substituent chain alkyl group or a substituted group, Or a similar chain alkenyl group to the same as R ¹⁰¹ .
Among these, Rd ¹ may have an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent. A chain hydrocarbon group is preferred. The substituent that these groups may have is preferably a hydroxyl group, a fluorine atom or a fluorinated alkyl group.
The aromatic hydrocarbon group is more preferably a phenyl group or a naphthyl group.
The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane.
As the chain hydrocarbon group, a chain alkyl group is preferable. The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a nonyl group. A linear alkyl group such as a group or decyl group; 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group And branched chain alkyl groups such as 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, and the like.

When the chain alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms. The fluorinated alkyl group, which is more preferably ˜4, may contain an atom other than a fluorine atom. Examples of atoms other than fluorine atoms include oxygen atoms, carbon atoms, hydrogen atoms, sulfur atoms, and nitrogen atoms.
Rd ¹ is preferably a fluorinated alkyl group in which some or all of the hydrogen atoms constituting the linear alkyl group are substituted by fluorine atoms, and the hydrogen atom constituting the linear alkyl group It is preferable that all are fluorinated alkyl groups (linear perfluoroalkyl groups) substituted with fluorine atoms.

  Preferred specific examples of the anion moiety of the component (d1-1) are shown below.

-Cation part In formula (d1-1), Mm ⁺ is an m-valent organic cation.
The organic cation of M ^{m +} is not particularly limited, and examples thereof include those similar to the cations represented by the general formulas (ca-1) to (ca-4), respectively, and the formula (ca-1- Cations represented by 1) to (ca-1-63) are preferable.
As the component (d1-1), one type may be used alone, or two or more types may be used in combination.

{(D1-2) component}
· During anion formula (d1-2), Rd ² is has an optionally substituted cyclic group which may have a substituent chain alkyl group or a substituted group, A chain alkenyl group which may be the same as R ¹⁰¹ .
However, a fluorine atom is not bonded to a carbon atom adjacent to the S atom in Rd ² (not fluorine-substituted). Thereby, the anion of (d1-2) component turns into a moderate weak acid anion, and the quenching ability of (D) component improves.
Rd ² is preferably an aliphatic cyclic group which may have a substituent, and a group in which one or more hydrogen atoms have been removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane or the like. (It may have a substituent); it is more preferably a group obtained by removing one or more hydrogen atoms from camphor or the like.
The hydrocarbon group of Rd ² may have a substituent, and examples of the substituent include a hydrocarbon group (aromatic hydrocarbon group, aliphatic hydrocarbon group) in Rd ¹ of the formula (d1-1). The same thing as the substituent which may have is mentioned.

  Preferred specific examples of the anion moiety of the component (d1-2) are shown below.

-Cation part In formula (d1-2), Mm ⁺ is an m-valent organic cation, and is the same as Mm ⁺ in formula (d1-1).
As the component (d1-2), one type may be used alone, or two or more types may be used in combination.

{(D1-3) component}
During Anion formula (d1-3), Rd ³ is have an optionally substituted cyclic group which may have a substituent chain alkyl group or a substituted group, A chain alkenyl group that may be the same as R ^101, and is preferably a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group. Among them, a fluorinated alkyl group is preferable, and the same as the fluorinated alkyl group for Rd ¹ is more preferable.

In formula (d1-3), Rd ⁴ may have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. Examples of the chain alkenyl group include those similar to R ¹⁰¹ .
Among these, an alkyl group, an alkoxy group, an alkenyl group, or a cyclic group which may have a substituent is preferable.
The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group. Tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. A part of the hydrogen atoms of the alkyl group of Rd ⁴ may be substituted with a hydroxyl group, a cyano group, or the like.
The alkoxy group in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms. Specific examples of the alkoxy group having 1 to 5 carbon atoms include methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- Examples include butoxy group and tert-butoxy group. Of these, a methoxy group and an ethoxy group are preferable.

Examples of the alkenyl group in Rd ⁴ include those similar to R ¹⁰¹ described above, and a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group, and a 2-methylpropenyl group are preferable. These groups may further have, as a substituent, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

Examples of the cyclic group for Rd ⁴ include the same groups as those described above for R ^101, and one or more hydrogen atoms are removed from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. An alicyclic group or an aromatic group such as a phenyl group or a naphthyl group is preferred. When Rd ⁴ is an alicyclic group, the resist composition is well dissolved in an organic solvent, whereby the lithography properties are improved. In addition, when Rd ⁴ is an aromatic group, in lithography using EUV or the like as an exposure light source, the resist composition is excellent in light absorption efficiency, and sensitivity and lithography characteristics are good.

In formula (d1-3), Yd ¹ represents a single bond or a divalent linking group.
The divalent linking group in Yd ¹ is not particularly limited, but may be a divalent hydrocarbon group (aliphatic hydrocarbon group or aromatic hydrocarbon group) which may have a substituent, or a hetero atom containing 2 Valent linking groups and the like. These may be the same as those exemplified in the description of the divalent linking group of Ya ²¹ in the formula (a2-1).
Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is preferably a linear or branched alkylene group, and more preferably a methylene group or an ethylene group.

  Preferred specific examples of the anion moiety of the component (d1-3) are shown below.

-Cation part In formula (d1-3), Mm ⁺ is an m-valent organic cation, and is the same as Mm ⁺ in formula (d1-1).
As the component (d1-3), one type may be used alone, or two or more types may be used in combination.

As the component (D1), only one of the above components (d1-1) to (d1-3) may be used, or two or more may be used in combination.
The content of the component (D1) is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, with respect to 100 parts by mass of the component (A). More preferably, it is part by mass.
When the content of the component (D1) is not less than the preferable lower limit value, particularly good lithography characteristics and a resist pattern shape can be obtained. On the other hand, when it is not more than the upper limit value, the sensitivity can be maintained well and the throughput is also excellent.

  The manufacturing method of said (d1-1) component and (d1-2) component is not specifically limited, It can manufacture by a well-known method.

  The content of the component (D1) is preferably 0.5 to 10.0 parts by mass and more preferably 0.5 to 8.0 parts by mass with respect to 100 parts by mass of the component (A). 1.0 to 8.0 parts by mass is even more preferable. When it is at least the lower limit of the above range, particularly good lithography properties and resist pattern shape can be obtained. When the amount is not more than the upper limit of the above range, the sensitivity can be maintained satisfactorily and the throughput is excellent.

((D2) component)
(D) component may contain the nitrogen-containing organic compound component (henceforth (D2) component) which does not correspond to the said (D1) component.
The component (D2) is not particularly limited as long as it functions as an acid diffusion control agent and does not correspond to the component (D1), and any known component may be used. Of these, aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are preferred.
An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms.
Examples of the aliphatic amine include an amine (alkyl amine or alkyl alcohol amine) or a cyclic amine in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms.
Specific examples of alkylamines and alkyl alcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di- -Dialkylamines such as n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine , Trialkylamines such as tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, tri-n-dodecylamine; diethanolamine, triethanolamine, diisopropanolamine, Li isopropanolamine, di -n- octanol amines, alkyl alcohol amines tri -n- octanol amine. Among these, a trialkylamine having 5 to 10 carbon atoms is more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable. Specifically, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5. 4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane, and the like.

  Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, tris {2 -(1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris [2- {2- (2-hydroxy Ethoxy) ethoxy} ethyl] amine, triethanolamine triacetate and the like, and triethanolamine triacetate is preferable.

As the component (D2), an aromatic amine may be used.
Aromatic amines include aniline, pyridine, 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, diphenylamine, triphenylamine, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxy. And carbonylpyrrolidine.

(D2) A component may be used independently and may be used in combination of 2 or more type.
(D2) A component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component. By setting the content in the above range, the resist pattern shape, the stability over time, and the like are improved.

(D) A component may be used individually by 1 type and may be used in combination of 2 or more type.
When the resist composition of this invention contains (D) component, it is preferable that (D) component is 0.1-15 mass parts with respect to 100 mass parts of (A) component, 0.3- More preferably, it is 12 mass parts, and it is still more preferable that it is 0.5-12 mass parts. When it is at least the lower limit of the above range, lithography properties such as LWR are further improved when a resist composition is used. Further, a better resist pattern shape can be obtained. When the amount is not more than the upper limit of the above range, the sensitivity can be maintained satisfactorily and the throughput is excellent.

<Optional component>
[(E) component]
In the present invention, the resist composition includes organic carboxylic acid, phosphorus oxo acid and derivatives thereof as optional components for the purpose of preventing sensitivity deterioration and improving the resist pattern shape and stability with time. At least one compound (E) selected from the group (hereinafter referred to as component (E)) can be contained.
As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Examples of phosphorus oxo acids include phosphoric acid, phosphonic acid, and phosphinic acid. Among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include esters in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of phosphinic acid derivatives include phosphinic acid esters and phenylphosphinic acid.
(E) A component may be used individually by 1 type and may use 2 or more types together.
(E) A component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

[(F) component]
In the present invention, the resist composition may contain a fluorine additive (hereinafter referred to as “component (F)”) in order to impart water repellency to the resist film.
Examples of the component (F) include JP 2010-002870 A, JP 2010-032994 A, JP 2010-277043 A, JP 2011-13569 A, and JP 2011-128226 A. The described fluorine-containing polymer compound can be used.
More specifically, examples of the component (F) include a polymer having a structural unit (f1) represented by the following formula (f1-1). As the polymer, a polymer (homopolymer) consisting only of the structural unit (f1) represented by the following formula (f1-1); a structural unit (f1) represented by the following formula (f1-1); A copolymer with the structural unit (a1); a structural unit (f1) represented by the following formula (f1-1); a structural unit derived from acrylic acid or methacrylic acid; and the structural unit (a1) It is preferable that it is a copolymer. Here, as the structural unit (a1) copolymerized with the structural unit (f1) represented by the following formula (f1-1), 1-ethyl-1-cyclooctyl (meth) acrylate or the formula (a1) -2-01) is preferred.

［式中、Ｒは前記同様であり、Ｒｆ^１０２およびＲｆ^１０３はそれぞれ独立して水素原子、ハロゲン原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基を表し、Ｒｆ^１０２およびＲｆ^１０３は同じであっても異なっていてもよい。ｎｆ^１は１〜５の整数であり、Ｒｆ^１０１はフッ素原子を含む有機基である。］

[Wherein, R is the same as defined above, and Rf ¹⁰² and Rf ¹⁰³ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, Rf ¹⁰² and Rf ¹⁰³ may be the same or different. nf ¹ is an integer of ¹ to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom. ]

In formula (f1-1), R is the same as described above. R is preferably a hydrogen atom or a methyl group.
In formula (f1-1), examples of the halogen atom for Rf ¹⁰² and Rf ¹⁰³ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. Examples of the alkyl group having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ include the same as the alkyl group having 1 to 5 carbon atoms of R, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ include a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with a halogen atom. Can be mentioned. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. The inter alia ^{Rf 102} and ^{Rf 103,} hydrogen atom, a fluorine atom, or an alkyl group having 1-5 carbon atoms preferably, hydrogen atom, a fluorine atom, methyl group or ethyl group is preferred.
In formula (f1-1), nf ¹ is an integer of ¹ to 5, preferably an integer of 1 to 3, and more preferably 1 or 2.

In formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms. The carbon number of 1 to 10 is particularly preferable.
The hydrocarbon group containing a fluorine atom preferably has 25% or more of the hydrogen atoms in the hydrocarbon group fluorinated, more preferably 50% or more fluorinated, and 60% or more. Fluorination is particularly preferable because the hydrophobicity of the resist film during immersion exposure is increased.
Among ^these, as ^{Rf 101,} particularly preferably a fluorinated hydrocarbon group having 1 to 5 carbon atoms, a methyl _{group, -CH 2 -CF 3, -CH 2} -CF 2 -CF 3, -CH (CF 3) 2 _{, -CH} 2 _-CH 2 _-CF 3, and most preferably _{-CH 2 -CH 2 -CF 2 -CF 2} -CF 2 -CF 3.

(F) As for the weight average molecular weight (Mw) (polystyrene conversion reference | standard by gel permeation chromatography), 1000-50000 are preferable, 5000-40000 are more preferable, and 10000-30000 are the most preferable. If it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and if it is above the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
The dispersity (Mw / Mn) of the component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

(F) A component may be used individually by 1 type and may use 2 or more types together.
(F) A component is used in the ratio of 0.5-10 mass parts with respect to 100 mass parts of (A) component.

  In the present invention, the resist composition further contains an optional miscible additive, for example, an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, and an antihalation agent. A dye or the like can be added and contained as appropriate.

[(S) component]
In the present invention, the resist composition can be produced by dissolving the material in an organic solvent (hereinafter sometimes referred to as (S) component).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution. Conventionally, any one of known solvents for chemically amplified resists can be used. Two or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone (MEK), cyclohexanone, methyl-n-pentyl ketone (2-heptanone), methyl isopentyl ketone; ethylene glycol, diethylene glycol, propylene glycol, di- Polyhydric alcohols such as propylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, the polyhydric alcohols or compounds having the ester bond Monoalkyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether Derivatives of polyhydric alcohols such as compounds having an ether bond such as propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) among these; cyclic ethers such as dioxane, , Methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate, etc .; anisole, ethyl benzyl ether, cresyl methyl Ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene And aromatic organic solvents such as dimethyl sulfoxide (DMSO).
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Of these, PGMEA, PGME, γ-butyrolactone, and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
More specifically, when EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA: EL or cyclohexanone is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. . Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3.
In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
(S) The usage-amount of a component is not specifically limited, It is a density | concentration which can be apply | coated to a board | substrate etc., and is suitably set according to a coating film thickness. Generally, it is used so that the solid content concentration of the resist composition is in the range of 1 to 20% by mass, preferably 2 to 15% by mass.

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

[Preparation of base agent]
100 parts by mass of the following resin composition I (l / m = 71.2 / 28.8, Mw = 40400, Mw / Mn = 1.77) in propylene glycol monomethyl ether acetate (PGMEA) and the following compound (B) -1 was contained in the amount shown in Table 1 to prepare base materials 1 to 8 having a solid content concentration of 0.4 mass%.

[Measurement of contact angle of base materials 1 to 8]
Water was dropped on the surfaces of the base materials 1 to 8, and the contact angle (static contact angle) was measured using DROP MASTER-700 (product name, manufactured by Kyowa Interface Science Co., Ltd.) (Measurement of the contact angle) : 2 μL of water). The measured values are set as “contact angle (°)”, and the results are shown in Table 2.

Examples 1-5, Comparative Examples 1-3
An organic antireflection film composition “ARC29A” (trade name, manufactured by Brewer Science Co., Ltd.) is applied onto an 8-inch silicon wafer using a spinner, and baked at 205 ° C. for 60 seconds on a hot plate and dried. Thus, an organic antireflection film having a film thickness of 82 nm was formed.
Next, each base agent shown in Table 2 is applied onto the organic antireflection film using a spinner, and the layer made of the base agent having a film thickness of 10 nm is formed by baking at 250 ° C. for 1 minute and drying. Formed on a substrate.

  Next, block copolymer 1 of PS-PMMA (Mw 42,400, PS / PMMA composition ratio (molar ratio) 55/45, dispersity 1.07, period 26 nm) or block copolymer so as to cover the neutralized film part 2 (Mw 42,400, PS / PMMA composition ratio (molar ratio) 75/25, dispersity 1.07, period 26 nm) PGMEA solution (2 mass%) was spin-coated (rotation number 1500 rpm, 60 seconds). The substrate coated with the PS-PMMA block copolymer was annealed by heating at 240 ° C. for 60 seconds under a nitrogen stream, thereby forming a phase separation structure.

As a result, in Examples 1 to 5 and Comparative Examples 1 to 3, a structure including a phase separation structure on the neutralized film could be produced. In any case, a lamellar pattern was formed when the block copolymer 1 was used, and a cylinder pattern was formed when the block copolymer 2 was used.
The substrate on which phase separation has been formed is subjected to oxygen plasma treatment (200 mL / min, 40 Pa, 40 ° C., 200 W, 20 seconds) using TCA-3822 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) to selectively select a phase composed of PMMA. The surface of the obtained substrate was observed with a scanning electron microscope SEMSU8000 (manufactured by Hitachi High-Technologies Corporation). ◎ if a uniform pattern (vertical lamella pattern or cylinder pattern) is observed, ○ if the base material where a uniform pattern (vertical lamella pattern or cylinder pattern) is not formed is observed, ○, uniform pattern (vertical A base material in which no lamella pattern or cylinder pattern) was observed was evaluated as Δ. The results are shown in Table 2.

  In Examples 1 to 5 using the base materials 4 to 8 of the present invention, a uniform vertical lamella pattern or cylinder pattern was observed.

The following compounds were synthesized by a conventional method, and polymer compound 1 was synthesized by a conventional method.
Polymer compound 1:
(1) / (2) / (3) / (4) / (5) = 31.9 / 29.2 / 13.0 / 16.7 / 19.2
Mw = 7600, Mw / Mn = 1.62

  The following compound (B) -1 is 7.5 parts by mass, the following compound (D) -1 is 4.5 parts by mass, the following polymer compound (F) -1 ( (Molar ratio: 1 / m = 77/23), Mw 23100, Mw / Mn 1.78), 3.0 parts by mass, propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether / cyclohexanone = 45/30/25 It mixed and melt | dissolved in the mixed solvent of (mass ratio), and the resist composition 1 with a solid content concentration of 2.5 mass% was prepared.

Examples 6-7, Comparative Example 4
[Formation of resist pattern]
An organic antireflection film composition “ARC29A” (trade name, manufactured by Brewer Science Co., Ltd.) is applied onto an 8-inch silicon wafer using a spinner, and baked at 205 ° C. for 60 seconds on a hot plate and dried. Thus, an organic antireflection film having a film thickness of 82 nm was formed.
Next, each base agent shown in Table 3 is applied onto the organic antireflection film using a spinner, and the layer made of the base agent having a film thickness of 10 nm is formed by baking at 250 ° C. for 1 minute and drying. Formed on a substrate.

Then, the resist composition 1 is applied onto the layer made of the base agent using a spinner, prebaked (PAB) on a hot plate at 85 ° C. for 60 seconds, and dried. A resist film having a thickness of 75 nm was formed.
Next, an ArF immersion exposure apparatus NSR-S609 (manufactured by Nikon Corporation; NA (numerical aperture) = 1.07, Cross pole (in / out = 0.78 / 0.97) with Polaro), ArF excimer laser, Irradiated. Then, PEB treatment was performed at 115 ° C. for 60 seconds. Furthermore, solvent development is carried out with a 2.38 mass% TMAH aqueous solution (trade name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23 ° C. for 13 seconds, followed by water rinsing with pure water for 30 seconds, followed by shaking off and drying. went.
Subsequently, post-baking was performed on a hot plate at 100 ° C. for 60 seconds.

  As a result, in Examples 6 to 7 and Comparative Example 4, a line and space pattern having a line width of 160 nm and a pitch width of 320 nm was formed on the neutralization film. About the formed pattern, the height of the pattern and the width of the pattern were measured. The results are shown in Table 3.

[Evaluation of pattern height]
The height (nm) of the pattern was measured using a wafer shape / characteristic measuring device (trade name: SCD-XT, manufactured by KLA Tencor). The results are shown in Table 3.
[Evaluation of pattern width]
The width (nm) of the pattern was measured with a length measurement SEM (scanning electron microscope, acceleration voltage 300 V, trade name: S-9380, manufactured by Hitachi High-Technologies Corporation) from above the pattern. A triple value (3σ) of the standard deviation (σ) calculated from the measurement result was obtained. The results are shown in Table 3 as “pattern width (nm)”.
[Development defect evaluation]
About the resist pattern obtained as described above, surface development defects were visually observed from a photograph of a length measurement SEM (manufactured by Hitachi, Ltd., product name: S-9220). The results of evaluation based on the following criteria are shown in Table 3.
A: Visually no development defects.
A ′: 1-2 development defects visually.
B: 3 to 5 development defects visually.
D: Six or more development defects visually.

  In Examples 6 to 7 using the base agent of the present invention, compared to Comparative Example 4, the pattern height and pattern width were excellent, and there were few development defects.

DESCRIPTION OF SYMBOLS 1, 11 ... Substrate 2, 12 ... Neutralization film layer containing surface treating agent 3 ... Layer containing block copolymer 14 ... Resist pattern 3a, 13a ... Layer made of _B block 3b, the layer consisting 13b · · · _{P A} block

Claims (2)

On a substrate, comprising the steps of coating a lower Chizai, to form a layer made of the lower land agent,
Thereafter, a step of forming a resist film by applying a resist composition that generates an acid upon exposure and changes its solubility in a developing solution by the action of the acid on the layer made of the base agent;
Exposing the resist film;
Developing the resist film to form a resist pattern;
Forming a layer containing a block copolymer in which a plurality of types of blocks are bonded on the layer made of the base agent on which the resist pattern is formed, and then phase-separating the layer containing the block copolymer;
A step of selectively removing a phase composed of at least one block of a plurality of types of blocks constituting the block copolymer from the layer containing the block copolymer;
A Rupa turn forming method having a,
The base agent includes a resin component (A ′) having a structural unit derived from an aromatic ring-containing monomer, and an acid generator component (B) that generates an acid upon exposure, and 100 parts by mass of the resin component ( The pattern formation method characterized by including 5-50 mass parts of said acid generator components (B) with respect to A '). On a substrate, comprising the steps of coating a lower Chizai, to form a layer made of the lower land agent,
Thereafter, a step of forming a layer containing a block copolymer in which a plurality of types of polymers are bonded on the layer made of the base agent;
Phase-separating the layer containing the block copolymer;
A Rupa turn forming method having a,
The base agent includes a resin component (A ′) having a structural unit derived from an aromatic ring-containing monomer, and an acid generator component (B), and 100 parts by mass of the resin component (A ′), Including 5 to 50 parts by mass of the acid generator component (B),
The pattern forming method, wherein the acid generator component (B) includes an onium salt acid generator having a cation moiety represented by any one of the following general formulas (ca-1) to (ca-4) : .

[Wherein R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² are each independently an aryl having a substituent represented by any of the following formulas (ca-r-1) to (ca-r-7): Group, an alkyl group having a substituent represented by any of the following formulas (ca-r-1) to (ca-r-7), or the following formulas (ca-r-1) to (ca-r-7) an alkenyl group having a substituent represented by any one ^{of, R 201 ~R 203, R 206} ~R 207, R 211 ~R 212 is forms a ring with the sulfur atom bonded to each other May be. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ²¹⁰ is an aryl group, alkyl group, alkenyl group, or —SO ₂ — containing an optionally substituted substituent. A cyclic group, L ²⁰¹ represents —C (═O) — or —C (═O) —O—, Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group, and x represents 1 or 2 and W ²⁰¹ represents a (x + 1) -valent linking group. ]

[Wherein, R ′ ²⁰¹ each independently represents a hydrogen atom, an optionally substituted cyclic group, a chain alkyl group, or a chain alkenyl group. ]

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