KR102165966B1 - Undercoat agent and pattern forming method - Google Patents

Abstract

A brush used to phase-separate a layer containing a block copolymer in which a plurality of types of blocks formed on a substrate are bonded, containing a resin component, the resin component having a structural unit having an aromatic group, and a hydroxyalkyl group A brush containing a structural unit having and a structural unit not having an aromatic group and a hydroxyalkyl group.

Description

Base agent and pattern formation method {UNDERCOAT AGENT AND PATTERN FORMING METHOD}

The present invention relates to a brush and a method for forming a pattern.

This application claims priority based on Japanese Patent Application No. 2013-031418 filed in Japan on February 20, 2013 and Japanese Patent Application No. 2013-260594 filed in Japan on December 17, 2013, Won here.

In recent years, as large-scale integrated circuits (LSIs) are further refined, a technique for processing a more delicate structure is required. In response to such a request, attempts to form a finer pattern using a phase-separated structure formed by self-assembly of a block copolymer in which incompatible blocks are bonded to each other are being started.

In order to use the phase separation of the block copolymer, it is essential to form the self-organizing nanostructure formed by microphase separation only in a specific region and arrange it in a desired direction. In order to realize such position control and orientation control, methods such as grapho epitaxy, which controls the phase separation pattern by guide patterns, and chemical epitaxy, which control the phase separation pattern by the difference in the chemical state of the substrate, have been proposed. Yes (see, for example, Non-Patent Document 1).

As one of the methods for forming a fine pattern by good phase separation of the block copolymer, the block on the substrate is formed by forming a neutral layer of the intermediate surface free energy of the surface free energy of two block chains on the substrate. A method is disclosed in which a surface in contact with a copolymer is set to a surface free energy having an intermediate value of the surface free energy of two block chains (for example, see Patent Document 1).

Japanese Patent Application Laid-Open No. 2008-36491

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

However, in the method described in Patent Document 1, it is necessary to control the surface free energy of the neutral layer by selecting a neutral layer material for which the surface free energy becomes a desired value each time depending on the type of block copolymer to be used. Therefore, as a brush that can obtain a good pattern by phase separation of the block copolymer, a brush that can be used more conveniently has been required.

In addition, conventional brushing agents have insufficient control of the surface condition of the brushing agent, and it was difficult to make it a brush with a wide temperature margin.

The present invention was made in view of the above circumstances, and as a brushing agent capable of manufacturing a substrate having a nanostructure designed with more freedom in position and orientation on the surface of the substrate by using phase separation of a block copolymer, temperature An object of the present invention is to provide a brush having a wide margin and a method for forming a pattern of a layer containing a block copolymer using the brush.

A first aspect of the present invention is a brushing agent used to phase-separate a layer containing a block copolymer in which a plurality of types of blocks formed on a substrate are bonded, and contains a resin component, and the resin component comprises an aromatic group. It is a brushing agent characterized by containing a structural unit which has, a structural unit which has a hydroxyalkyl group, and a structural unit which does not have an aromatic group and a hydroxyalkyl group. In the first aspect of the present invention, it is preferable that 10% or less of the structural units of the entire resin component are structural units having a hydroxyalkyl group.

The second aspect of the present invention is a step of applying the brush of the first aspect of the present invention on a substrate to form a layer made of the brush, and a block in which a plurality of types of polymers are bonded on the layer made of the brush. It is a pattern formation method characterized by including a step of forming a layer containing a copolymer and a step of phase-separating the layer containing the block copolymer.

In the present specification and claims, the term "aliphatic" is a relative concept with respect to aromatics, and is defined as meaning a group, compound, etc. that do not have aromaticity.

The "alkyl group" shall include a linear, branched and cyclic monovalent saturated hydrocarbon group unless otherwise specified.

The "alkylene group" shall include a linear, branched and cyclic divalent saturated hydrocarbon group unless otherwise specified. The alkyl group in the alkoxy group is also the same.

The "halogenated alkyl group" is a group in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The "fluorinated alkyl group" or the "fluorinated alkylene group" refers to a group in which some or all of the hydrogen atoms of the alkyl group or the alkylene group are substituted with fluorine atoms.

The "constituent unit" means a monomer unit (monomer unit) constituting a high molecular compound (resin, polymer, copolymer).

The "constituent unit derived from an acrylic acid ester" means a structural unit constituted by cleaving an ethylenic double bond of an acrylic acid ester.

"Acrylic acid ester" is a compound in which the hydrogen atom at the terminal of the carboxyl group of acrylic acid (CH ₂ =CH-COOH) is substituted with an organic group.

In the acrylic acid ester, a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent. The substituent that replaces the hydrogen atom bonded to the carbon atom at the α-position is an atom or group other than a hydrogen atom, and examples thereof include an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group. . In addition, unless otherwise noted, the carbon atom at the α-position of the acrylic acid ester refers to a carbon atom to which a carbonyl group is bonded.

Hereinafter, an acrylic acid 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 acrylic acid ester. In addition, acrylic acid esters and α-substituted acrylic acid esters are included and may be referred to as "(α-substituted) acrylic acid esters".

The "constituent unit derived from hydroxystyrene or a hydroxystyrene derivative" means a structural unit formed by cleaving an ethylenic double bond of a hydroxystyrene or a hydroxystyrene derivative.

The term "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 a halogenated alkyl group, and derivatives thereof. As their derivatives, the hydrogen atom of the hydroxyl group of hydroxystyrene in which the hydrogen atom at the α-position may be substituted with an organic group is substituted with an organic group, and a hydroxyl group in the benzene ring of the hydroxystyrene in which the hydrogen atom at the α-position may be substituted with a substituent. And those with other substituents bonded thereto. In addition, the α-position (a carbon atom in the α-position) refers to a carbon atom to which a benzene ring is bonded, unless otherwise noted.

Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include the same as those exemplified as the substituent at the α-position in the α-substituted acrylate ester.

The "constituent unit derived from a vinylbenzoic acid or a vinylbenzoic acid derivative" means a structural unit constituted by cleavage of an ethylenic double bond of a vinylbenzoic acid or a vinylbenzoic acid derivative.

The term "vinylbenzoic acid derivative" is a concept in which a hydrogen atom at the α-position of vinylbenzoic acid is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As their derivatives, the hydrogen atom of the carboxyl group of vinylbenzoic acid in which the hydrogen atom at the α-position may be substituted with an organic group, and the hydroxyl group and carboxyl group in the benzene ring of the vinylbenzoic acid in which the hydrogen atom at the α-position may be substituted with a substituent. And those with other substituents bonded thereto. In addition, the α-position (a carbon atom in the α-position) refers to a carbon atom to which a benzene ring is bonded, unless otherwise noted.

The term "styrene" is a concept including styrene and those in which the hydrogen atom at the α-position of styrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group.

The "constituent units derived from styrene" and "constituent units derived from a styrene derivative" mean a structural unit constituted 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, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pen And a butyl group, an isopentyl group, and a neopentyl group.

Further, specific examples of the halogenated alkyl group as the substituent at the α-position include a group in which some or all of the hydrogen atoms in the “alkyl group as the substituent at the α-position” are substituted with a halogen atom. 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.

Further, specifically, the hydroxyalkyl group as the substituent at the α-position includes a group in which a part or all of the hydrogen atoms of the “alkyl group as the substituent at the α-position” is substituted with a hydroxyl group. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.

"Exposure" is a concept that includes the entire irradiation of radiation.

According to the present invention, as a brushing agent that can easily manufacture a substrate having a nanostructure designed with more freedom in position and orientation on the surface of the substrate by using phase separation of a block copolymer, a substrate having a wide temperature margin It is possible to provide a method for forming a pattern of a layer containing an agent and a block copolymer using the brush.

1 is a schematic process chart for explaining an embodiment example of a second aspect of the present invention.

<< not subject >>

The brush agent of the present invention is a brush agent used to phase-separate a layer containing a block copolymer in which a plurality of types of blocks formed on a substrate are bonded, and contains a resin component, and the resin component has an aromatic group. It is characterized by containing a structural unit, a structural unit having a hydroxyalkyl group, and a structural unit not having an aromatic group and a hydroxyalkyl group.

The brushing agent of the present invention is used to phase-separate a layer containing a block copolymer to which a plurality of types of polymers are bonded formed on a substrate. Specifically, the brushing agent of the present invention is applied on a substrate to form a layer made of a brushing agent (also referred to as a neutralizing film), and then a layer containing a plurality of types of block copolymers is formed thereon. , The substrate surface on which the layer made of the brush is formed on the surface can be made to 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 formation method of the layer containing the block copolymer, which can use the brush of the present invention, will be described in the second aspect of the present invention.

<Resin component (A)>

The brush composition of the present invention contains a resin component (A) (hereinafter, sometimes referred to as ``resin component (A)''), and the resin component (A) is a structural unit having an aromatic group and a hydroxyalkyl group It contains a structural unit which has and does not have an aromatic group and a hydroxyalkyl group.

In the present specification and the claims, the "resin component" means a polymer having a molecular weight of 1000 or more. As the molecular weight of the polymer, the mass average molecular weight in terms of polystyrene by GPC (gel permeation chromatography) is used.

[Constituent unit having an aromatic group]

In the present invention, the resin component (A) contains a structural unit having an aromatic group (hereinafter, it may be referred to as "structural unit (a1)").

[Constituent unit (a1)]

The structural unit (a1) is a structural unit which has an aromatic ring. The component (A) contains a structural unit having an aromatic ring as the structural unit (a1), so that even when a block copolymer having blocks having various properties is used, it should have an appropriate affinity for the block copolymer. I can.

The aromatic ring is preferably C6-C18, and specifically, aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene and phenanthrene; An aromatic heterocycle in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom; And the like. Examples of the hetero atom in the aromatic heterocycle 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,

An aromatic compound having a vinyl group (a compound containing an aromatic ring);

-Aromatic compound having a (meth)acryloyl group;

-Phenol compounds which are constituents of a novolac resin, etc. are mentioned.

Among them, structural units derived from compounds in which one of the hydrogen atoms bonded to the carbon atoms forming the ring in the aromatic ring which may have a substituent group is substituted with a vinyl group; Alternatively, as 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, a structural unit having an aromatic ring is exemplified as a preferable one. Here, the vinyl group may be one in which a carbon atom bonded to an aromatic ring among the carbon atoms 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 vinyl anthracene or a derivative thereof is particularly preferable.

As ``styrene or a derivative thereof,'' styrene 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 benzene ring may be substituted with a substituent other than a hydroxyl group (hereinafter, styrene bonded to the carbon atom at the α-position Styrene in which a hydrogen atom is substituted with a substituent is sometimes referred to as “α-substituted styrene”, and styrene and α-substituted styrene whose positions are not substituted are sometimes referred to as “(α-substituted) styrene.” The same applies to other similar compounds. (A), hydroxystyrene 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 benzene ring may be substituted with a substituent other than a hydroxyl group (hereinafter referred to as ``(α-substituted) hydroxystyrene'' In some cases), (α substitution) A compound in which the hydrogen atom of the hydroxyl group of hydroxystyrene 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 other than the hydroxyl group and the carboxyl group. Vinylbenzoic acid which may be substituted with a substituent (hereinafter, sometimes referred to as (α-substituted) vinylbenzoic acid), a compound in which a hydrogen atom of the carboxyl group of (α-substituted) vinylbenzoic acid is substituted with an organic group.

In α-substituted styrene, α-substituted hydroxystyrene and α-substituted vinylbenzoic acid, the substituent bonded to the carbon atom at the α-position is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, 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 from the viewpoint of industrial availability.

The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, and specifically, a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pen And a butyl group, an isopentyl group, and a neopentyl group.

Further, specific examples of the halogenated alkyl group as the substituent at the α-position include a group in which some or all of the hydrogen atoms of the “alkyl group as the substituent at the α-position” 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.

Hydroxystyrene is a compound in which one vinyl group and at least one hydroxyl group are bonded to a benzene ring. The number of hydroxyl groups bonded to the benzene ring is preferably 1 to 3, and particularly preferably 1. The bonding position of the hydroxyl group in the benzene ring is not particularly limited. When the number of hydroxyl groups is 1, the para 4 position of the bonding position of the vinyl group is preferable. When the number of hydroxyl groups is an integer of 2 or more, arbitrary bonding positions can be combined.

Vinylbenzoic 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.

It is not particularly limited as a substituent other than a hydroxyl group and a carboxyl group that may be bonded to the benzene ring of styrene or its derivatives, and examples thereof include a halogen atom, an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, etc. have. 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'', 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 naphthalene ring may be substituted with a substituent other than a hydroxyl group (hereinafter, ``(α substituted) vinyl Naphthalene''), vinyl (hydroxynaphthalene) 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 naphthalene ring may be substituted with a substituent other than a hydroxyl group (hereinafter, ``( (alpha) substitution) vinyl (hydroxynaphthalene)" in some cases), (α substitution) a compound in which the hydrogen atom of the hydroxyl group of vinyl (hydroxynaphthalene) is substituted with a substituent. In α-substituted vinylnaphthalene and α-substituted vinyl (hydroxynaphthalene), the substituent for substituting a hydrogen atom bonded to a carbon atom at the α-position is the same as a 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. The number of hydroxyl groups bonded to the naphthalene ring is preferably 1 to 3, and particularly preferably 1. The bonding position of the hydroxyl group in the naphthalene ring is not particularly limited. When a vinyl group is bonded to the position 1 or 2 of the naphthalene ring, any of the positions 5 to 8 of the naphthalene ring is preferable. In particular, when the number of hydroxyl groups is one, any of the 5 to 7 positions of the naphthalene ring is preferable, and the 5 or 6 position is preferable. When the number of hydroxyl groups is an integer of 2 or more, arbitrary bonding positions can be combined.

Examples of the substituents that may be bonded to the naphthalene ring of vinyl naphthalene or its derivatives include those exemplified as the substituents that may be bonded to the benzene ring of the above (α-substituted) styrene.

Examples of "vinyl anthracene or a derivative thereof" include vinyl anthracene 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 anthracene ring may be substituted with a substituent other than a hydroxyl group. As a substituent, it is the same as a substituent such as α-substituted styrene.

"Acrylic acid ester" is a compound in which the hydrogen atom at the terminal of the carboxyl group of acrylic acid (CH ₂ =CH-COOH) is substituted with an organic group.

Acrylic acid in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent (hereinafter sometimes referred to as ``(α-substituted) acrylic acid”) or a substituent bonded to the carbon atom at the α-position of the ester is α-substituted vinyl In naphthalene and α-substituted vinyl (hydroxynaphthalene), it is the same as a substituent such as α-substituted styrene. In addition, the α-position (carbon atom in the α-position) of a structural unit derived from an acrylic acid ester means a carbon atom to which a carbonyl group is bonded, unless otherwise noted.

(α substitution) It does not specifically limit as an organic group which the acrylic acid ester has.

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

[Formula 1]

[In the formula, 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. X ^c and X ^d are each independently 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, a plurality of R ^c may be the same or different, respectively. 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 to It is 7, and x+y+y'+z in Formula (a1-3) is 1-7. When y+z or y+y'+z is an integer of 2 or more, a plurality of R ^d may be the same or different, respectively. X ^Ar is a monovalent organic group having an aromatic ring.]

In the formula, the alkyl group and the halogenated alkyl group of R are the same as the alkyl group and the halogenated alkyl group exemplified as the substituent which may be bonded to the carbon atom at the α-position in the above description of the α-substituted styrene and the like. As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable.

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, and 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, Chlorine atom, etc.), silicon atom, etc.).

As the organic group of X ^c and X ^d , 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 some or all of the hydrogen atoms of the unsubstituted alkyl group are substituted with a substituent.

As the unsubstituted alkyl group, any of linear, branched and cyclic may be used. From the viewpoint of excellent resolution, an alkyl group having 1 to 10 carbon atoms is preferable, and an alkyl group having 1 to 5 carbon atoms is more preferable. Specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, n-pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, nonyl group, decyl group, etc. I can.

As a substituent in a substituted alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxo group (=O), a cyano group, etc. are mentioned, for example.

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, and a tert-butoxy group, and a methoxy group, The ethoxy group is most preferred.

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 a group in which some or all of the hydrogen atoms of the alkyl group are substituted with the halogen atoms.

Further, some of the carbon atoms constituting the unsubstituted or substituted alkyl group 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 -, -S(=O) ₂ -O-, -Si -Is preferred.

In the formula, examples of the halogen atom for 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 .

The C1-C5 alkyl group and the C1-C5 halogenated alkyl group of R ^c and R ^d are the same as the C1-C5 alkyl group and the C1-C5 halogenated alkyl group of R.

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

The structural unit (a1) contained in the component (A) may be one or two or more.

The proportion of the structural unit (a1) in the component (A) is preferably 10 to 95 mol%, more preferably 20 to 90 mol%, and more preferably 30 to 90 mol% with respect to all the structural units constituting the component (A). Is more preferable, and 50-85 mol% is most preferable.

By making the ratio of the structural unit (a1) more than the lower limit, the layer containing the block copolymer serving as the upper layer can be phase-separated favorably. Moreover, it becomes easy to balance with the structural unit (a2) by setting it as below an upper limit.

[Structural unit having a hydroxyalkyl group]

In the present invention, the resin component (A) contains a structural unit having a hydroxyalkyl group (hereinafter, it may be referred to as "structural unit (a15)"). In the present invention, the structural unit (a15) is not particularly limited as long as it has a hydroxyalkyl group, but for example, a structural unit derived from an acrylic acid ester having a hydroxyl group-containing alkyl group (hereinafter, described as ``constituent unit (a150)'' May be) is preferably used. However, among the structural units corresponding to the structural unit (a15), those corresponding to the structural unit having an aromatic group correspond to the structural unit (a1), and do not correspond to the structural unit (a15). As the structural unit (a150), a structural unit represented by the following general formula (a150-1) is preferable.

[Formula 2]

[In the formula, 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, and Y ¹ is an alkyl group having 1 to 5 carbon atoms.]

In formula (a150-1), R is the same as above. Y1 is a C1-C5 alkyl group, and it is preferable that it is an unsubstituted alkyl group. As the unsubstituted alkyl group, any of linear, branched and cyclic may be sufficient, but it is preferably a linear alkyl group.

Specifically, a methylene group, an ethylene group, an n-propylene group, and an n-butylene group are exemplified, and a methylene group or an ethylene group is preferable.

The structural unit (a15) contained in the component (A) may be one or two or more.

In the component (A), the proportion of the structural unit (a15) is preferably 15 mol% or less, more preferably 8 mol% or less, and further 6 mol% or less with respect to all the structural units constituting the component (A). It is preferred, and 5 mol% is most preferred.

It is considered that by making the ratio of the structural unit (a15) equal to or less than the upper limit, it becomes easy to balance the structural unit (a1) and the structural unit (a2) described later. In addition, by setting the content of the structural unit (a15) in the above range, it is speculated that the surface state of the brush is more stable.

[Structural unit not having an aromatic group and a hydroxyalkyl group]

In the present invention, the component (A) contains a structural unit that does not have an aromatic group and a hydroxyalkyl group (hereinafter, sometimes referred to as "structural unit (a2)").

[Constituent unit (a2)]

The structural unit (a2) is a structural unit which does not have an aromatic group and a hydroxyalkyl group. The component (A) can have affinity for various structural units of a block copolymer by containing the structural unit (a1), the structural unit (a15), and the structural unit (a2) together.

The structural unit (a2) is not particularly limited as long as it does not have the aromatic group and hydroxyalkyl group described in the structural unit (a1) and structural unit (a15) in its structure, but, for example,

-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, which does not have an aromatic group or a hydroxyalkyl group;

-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, which does not have an aromatic group and a hydroxyalkyl group;

-A structural unit derived from a cycloolefin or a derivative thereof, which does not have an aromatic group and a hydroxyalkyl group;

-A structural unit derived from a vinyl sulfonic acid ester, which does not have an aromatic group and a hydroxyalkyl group; And the like.

Among these, constituent units derived from acrylic acid or esters thereof in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent, and 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. The constitutional unit to be used is preferable.

As ``acrylamide or a derivative thereof'', acrylamide in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent (hereinafter, it may be referred to as (α substitution) acrylamide), (α substitution) amino group of acrylamide And compounds in which one or both of the terminal hydrogen atoms are substituted with a substituent.

Examples of the substituents that may be bonded to the carbon atom at the α-position of acrylamide or its derivatives include those exemplified as the substituents bonded to the carbon atom at the α-position of the α-substituted styrene.

(α Substitution) An organic group is preferable as a substituent for substituting one or both hydrogen atoms at the terminal of the amino group of acrylamide. Although it does not specifically limit as this organic group, For example, the thing similar to the organic group which the said (α-substituted) acrylic acid ester has is mentioned.

(α substitution) As a compound in which one or both of the hydrogen atoms at the end of the amino group of acrylamide are substituted with a substituent, for example, -C (=O) bonded to the carbon atom at the α position in the (α substitution) acrylic acid ester -O-, -C(=O)-N(R ^b )- [in the formula, R ^b Is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms].

In the formula, R ^b It is preferable that the alkyl group in is linear or branched.

As the structural unit (a2), a structural unit represented by the following formula (a2-1) or (a2-2) is particularly preferable.

[Formula 3]

[In the formula, R is the same as above, and X ^a , X ^b Are each independently a hydrogen atom or an organic group which does not have an aromatic group and a hydroxyalkyl group. R ^b Is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.]

In the formula, X ^a , X ^b Each independently represents a hydrogen atom or an organic group. The organic group does not have an aromatic group and a hydroxyalkyl group, and is not particularly limited as long as it is a group containing a carbon atom, and atoms other than carbon atoms (for example, hydrogen atom, oxygen atom, nitrogen atom, sulfur atom, halogen atom ( A fluorine atom, a chlorine atom, etc.), a silicon atom, etc.) may be included. As the organic group of X ^a and X ^b , specifically, among the groups described as the organic group of X ^c and X ^d , a group which does not have an aromatic group and a hydroxyalkyl group can be mentioned.

In the formula, the alkyl group having 1 to 5 carbon atoms for R ^b is the same as the alkyl group having 1 to 5 carbon atoms for R described above.

The structural unit (a2) contained in the component (A) may be one type or two or more types.

The proportion of the structural unit (a2) in the component (A) is preferably 5 to 90 mol%, more preferably 10 to 80 mol%, and more preferably 10 to 70 mol% with respect to all the structural units constituting the component (A). Is more preferable, and 14-50 mol% is most preferable.

By making the ratio of the structural unit (a2) more than the lower limit, the layer containing the block copolymer serving as the upper layer can be phase-separated favorably. Moreover, by setting it as the upper limit or less, it becomes easy to balance|balance with the structural unit (a1) and the structural unit (a15).

The mass average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography (GPC)) of the component (A) is not particularly limited, and is preferably 1000 to 200000, more preferably 1500 to 200000, and 2000 to 150000 is most preferred. If it is less than or equal to the upper limit of this range, it is sufficiently dissolved in the organic solvent described later, so that the coating property to the substrate is excellent, and if it is more than the lower limit of this range, the composition is excellent in the production stability of the polymer and also excellent in coating property to the substrate. do.

The degree of dispersion (Mw/Mn) is not particularly limited, and 1.0 to 5.0 are preferable, 1.0 to 3.0 are more preferable, and 1.0 to 2.5 are most preferable. Moreover, Mn represents a number average molecular weight.

The component (A) can be obtained by polymerizing a monomer that induces each structural unit by a known radical polymerization or the like using a radical polymerization initiator such as azobisisobutyronitrile (AIBN).

Further, in the component (A), at the time of the polymerization, for example, by using a chain transfer agent such as HS-CH ₂ -CH ₂ -CH ₂ -C(CF ₃ ) ₂ -OH in combination, -C ( You may introduce a CF ₃ ) ₂ -OH group.

As the monomer for inducing each structural unit, a commercially available monomer may be used, or may be synthesized using a known method.

In the brush composition of the present invention, the component (A) may be used alone or in combination of two or more.

When two or more types of component (A) are used in combination, the proportion of the structural unit (a1) in the component (A) is preferably 60 to 95 mol% with respect to all the structural units constituting the component (A), and 70 It is more preferable that it is -92 mol%.

When two or more types of (A) component are used in combination, the proportion of the structural unit (a2) in the component (A) is preferably 30 mol% or less, and 25 mol% with respect to all the structural units constituting the component (A). It is more preferable that it is the following.

When two or more types of component (A) are used in combination, the proportion of the structural unit (a15) in the component (A) is preferably 10 mol% or less, and 9 mol% with respect to all the structural units constituting the component (A). It is more preferable that it is the following.

In the brush composition of the present invention, the content of the component (A) may be appropriately adjusted according to the desired film thickness of the layer made of the brush.

The brush composition of the present invention contains the above-described structural unit (a1), structural unit (a15), and structural unit (a2), thereby forming a layer containing a block copolymer in which a plurality of types of blocks formed on a substrate are bonded. When used as a brushing agent used for phase separation, it is possible to more stably control the surface state of the brushing agent, and it is considered that a brushing agent having a wide temperature margin can be used.

<optional ingredient>

[Acid generator component; (B) component]

The brush composition of the present invention may further contain an acid generator component (B) (hereinafter, sometimes referred to as "component (B)"). The component (B) generates an acid by heating or exposing. The component (B) itself does not need to have acidity, but may be decomposed by heat or light to function as an acid.

The component (B) is not particularly limited, and what has been proposed as an acid generator for chemically amplified resists so far can be used.

Examples of such acid generators include thermal acid generators that generate acid by heating, photoacid generators that generate acid by exposure, and the like. Until now, onium salt-based acid generators such as iodonium salts and sulfonium salts , Oxime sulfonate acid generator, diazomethane acid generator such as bisalkyl or bisarylsulfonyldiazomethane, poly(bissulfonyl)diazomethane, nitrobenzylsulfonate acid generator , Iminosulfonate-based acid generators, disulfone-based acid generators and the like are known.

These acid generator components are generally known as photoacid generators (PAG), but also function as thermal acid generators (TAG). Therefore, as the acid generator component that can be used in the present invention, any of those conventionally known as acid generators for chemically amplified resist compositions can be used.

In addition, the "thermal acid generator that generates an acid by heating" specifically refers to a component that generates an acid by heating at 200°C or less, more preferably 50 to 150°C. By setting it as 200 degrees C or less, control of the generation|occurrence|production of an acid becomes easy. More preferably, by setting it as 50 degreeC or more, stability in a brush agent becomes favorable.

As the onium salt-based acid generator of component (B), in the anion moiety, sulfonic acid anion, carboxylic acid anion, sulfonylimide anion, bis(alkylsulfonyl)imide anion, and tris(alkylsulfonyl) It is preferable to have at least one anion group selected from the group consisting of methide anion and fluorinated antimony acid ion.

Moreover, what is represented by the following general formula (b-c1) or a general formula (b-c2) is mentioned as a cation part.

[Formula 4]

[In the formula, R ^{1 ″} to R ^{3 ″} and R ^{5 ″} to R ^{6 ″} each independently represent an aryl group, an alkyl group, or an alkenyl group which may have a substituent. Any two of R ^{1 "} to R ^{3 "} in the formula (b-c1) may be bonded to each other to form a ring together with the sulfur atom in the formula.]

In formula (b-c1), R ^{1 ″} to R ^{3 ″} each independently represent an aryl group, an alkyl group, or an alkenyl group which may have a substituent. Any two of R ^{1 "} to R ^{3 " may} be bonded to each other to form a ring together with the sulfur atom in the formula.

Examples of the aryl group for R ^{1 "} to R ^3" include an unsubstituted aryl group having 6 to 20 carbon atoms; Some or all of the hydrogen atoms of the unsubstituted aryl group are an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, an oxo group (=O), an aryl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, -C(=O) )-OR ^6' , -OC(=O)-R ^7' , -OR ^8' And a substituted aryl group substituted with the like. R ^6' , R ^7'and R ^8'are each a C 1 to C 25 linear, branched, or C 3 to C 20 cyclic saturated hydrocarbon group, or a C 2 to C 5 linear or branched chain It is an aliphatic unsaturated hydrocarbon group.

As the unsubstituted aryl group for R ^{1 ″} to R ^{3 ″} , an aryl group having 6 to 10 carbon atoms is preferable because it can be synthesized inexpensively. Specifically, a phenyl group and a naphthyl group are mentioned, for example.

As the alkyl group as a substituent in the substituted aryl group for R ^{1 "} to R ^3" , an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are most preferable.

The alkoxy group as the substituent in the substituted aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and is a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group. Most preferred.

The halogen atom as the substituent in the substituted aryl group is preferably a fluorine atom.

Examples of the aryl group as the substituent in the substituted aryl group include those similar to the aryl groups of the above R ^{1 "} to R ^{3 "} .

As the alkoxyalkyloxy group in the substituted aryl group, for example,

General formula: -OC(R ⁴⁷ )(R ⁴⁸ )-OR ⁴⁹

[In the formula, R ⁴⁷ , R ⁴⁸ Are each independently a hydrogen atom or a linear or branched alkyl group, R ⁴⁹ Is an alkyl group].

R ⁴⁷ , R ⁴⁸ WHEREIN: The number of carbon atoms of the alkyl group is preferably 1 to 5, and may be either a linear or branched chain, an ethyl group or a methyl group is preferable, and a methyl group is most preferable.

R ⁴⁷ , R ⁴⁸ It is preferable that at least one of silver is a hydrogen atom. In particular, it is more preferable that one is a hydrogen atom and the other is a hydrogen atom or a methyl group.

The alkyl group for R ⁴⁹ preferably has 1 to 15 carbon atoms and may be linear, branched or cyclic.

R ⁴⁹ The linear or branched alkyl group in is preferably having 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group.

R ⁴⁹ The cyclic alkyl group in is preferably 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, at least one hydrogen from polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, tetracycloalkane, which may or may not be substituted with an alkyl group having 1 to 5 carbon atoms, or a fluorine atom or a fluorinated alkyl group. And a group from which an atom has been removed. Cyclopentane, cyclohexane, etc. are mentioned as a monocycloalkane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like. Among them, a group in which at least one hydrogen atom has been removed from adamantane is preferable.

As the alkoxycarbonylalkyloxy group in the substituted aryl group, for example,

General formula: -OR ⁵⁰ -C(=O)-OR ⁵⁶

[In the formula, R ⁵⁰ is a linear or branched alkylene group, and R ⁵⁶ Is a tertiary alkyl group].

R ⁵⁰ The linear or branched alkylene group in is preferably 1 to 5 carbon atoms, for example, methylene group, ethylene group, trimethylene group, tetramethylene group, 1,1-dimethylethylene group And the like.

R ⁵⁶ As the tertiary alkyl group in, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-methyl-1-cyclopentyl group, 1-ethyl-1-cyclopentyl group, 1-methyl-1-cyclohexyl group, 1-ethyl-1-cyclohexyl group, 1-(1-adamantyl)-1-methylethyl group, 1-(1-adamantyl)-1-methylpropyl group , 1-(1-adamantyl)-1-methylbutyl group, 1-(1-adamantyl)-1-methylpentyl group; 1-(1-cyclopentyl)-1-methylethyl group, 1-(1-cyclopentyl)-1-methylpropyl group, 1-(1-cyclopentyl)-1-methylbutyl group, 1-(1-cyclo Pentyl)-1-methylpentyl group; 1-(1-cyclohexyl)-1-methylethyl group, 1-(1-cyclohexyl)-1-methylpropyl group, 1-(1-cyclohexyl)-1-methylbutyl group, 1-(1-cyclo Hexyl)-1-methylpentyl group, tert-butyl group, tert-pentyl group, tert-hexyl group, etc. are mentioned.

Further, the general formula: -OR ⁵⁰ -C(=O)-OR ⁵⁶ The group in which R ⁵⁶ is substituted with R ^56' is also mentioned. R ^56' is a hydrogen atom, an alkyl group, a fluorinated alkyl group, or an aliphatic cyclic group which may contain a hetero atom.

The alkyl group for R ^56' is the same as the alkyl group for R ⁴⁹ . The fluorinated alkyl group for R ^56' includes a group in which some or all of the hydrogen atoms in the alkyl group for R ⁴⁹ are substituted with fluorine atoms.

As the aliphatic cyclic group which may contain a hetero atom for R ^56' , an aliphatic cyclic group not containing a hetero atom, an aliphatic cyclic group containing a hetero atom in the ring structure, or a hydrogen atom in the aliphatic cyclic group is a hetero atom. And substituted ones.

Regarding R ^56' , examples of the aliphatic cyclic group that does not contain a hetero atom include groups in which one or more hydrogen atoms have been removed from polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. I can. Cyclopentane, cyclohexane, etc. are mentioned as a monocycloalkane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like. Among them, a group in which at least one hydrogen atom has been removed from adamantane is preferable.

Regarding R ^56' , specific examples of the aliphatic cyclic group containing a hetero atom in the ring structure include the following formulas (L1) to (L6), (S1) to (S4) and the like.

[Formula 5]

[In the formula, Q" is an alkylene group having 1 to 5 carbon atoms, -O-, -S-, -OR ⁹⁴ -or -SR ⁹⁵ -, and R ⁹⁴ and R ⁹⁵ are each independently an alkylene group having 1 to 5 carbon atoms And m is an integer of 0 or 1]

In the formula, the alkylene group for Q", R ⁹⁴ and R ⁹⁵ preferably has 1 to 5 carbon atoms. For example, a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, 1,1 -Dimethylethylene group, etc. are mentioned.

In these aliphatic cyclic groups, a part of the hydrogen atoms bonded to the carbon atoms constituting the ring structure may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (=O).

The alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably a methyl group, ethyl group, propyl group, n-butyl group, or 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, and a tert-butoxy group, and a methoxy group, The ethoxy group is most preferred.

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.

Regarding R ^56' , the hydrogen atom in the aliphatic cyclic group is substituted with a hetero atom, and specifically, a hydrogen atom in the aliphatic cyclic group is substituted with an oxygen atom (=O), and the like.

^{-C (= O) -OR 6 '} , -OC (= O) -R 7', -OR 8, R 7 ', R 8' are each shaped straight-chain having a carbon number of 1 ~ 25 ^{'R 6} in the ^" , A branched chain or a C 3 to C 20 cyclic saturated hydrocarbon group, or a C 2 to C 5 linear or branched aliphatic unsaturated hydrocarbon group.

The linear or branched saturated hydrocarbon group has 1 to 25 carbon atoms, preferably 1 to 15 carbon atoms, and more preferably 4 to 10 carbon atoms.

As a linear saturated hydrocarbon group, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, etc. are mentioned, for example.

Excluding the tertiary alkyl group as a branched chain saturated hydrocarbon group, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3- A methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, etc. are mentioned.

The linear or branched saturated hydrocarbon group may have a substituent. Examples of the substituent include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O), a cyano group, and a carboxyl group.

The alkoxy group as a substituent of the linear or branched saturated hydrocarbon group is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, A tert-butoxy group is preferable, and a methoxy group and an ethoxy group are most preferable.

Examples of the halogen atom as a substituent of the linear or branched saturated hydrocarbon group 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 a substituent of the linear or branched saturated hydrocarbon group include a group in which some or all of the hydrogen atoms of the linear or branched saturated hydrocarbon group are substituted with the halogen atoms.

As the C3-C20 cyclic saturated hydrocarbon group for R ^6' , R ^7'and R ^8' , either a polycyclic group or a monocyclic group may be used. For example, one hydrogen atom from a monocycloalkane Group to remove; And a group in which one hydrogen atom has been removed from a polycycloalkane such as a bicycloalkane, a tricycloalkane, and a tetracycloalkane. More specifically, from monocycloalkanes such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. And groups from which two hydrogen atoms have been removed.

The cyclic saturated hydrocarbon group may have a substituent. For example, some of the carbon atoms constituting the ring of the cyclic alkyl group may be substituted with a hetero atom, or the hydrogen atom bonded to the ring of the cyclic alkyl group may be substituted with a substituent.

Examples of the former include groups in which at least one hydrogen atom has been removed from a heterocycloalkane in which a part of the carbon atoms constituting the ring of the monocycloalkane or polycycloalkane is substituted with a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom. I can. Moreover, you may have an ester bond (-C(=O)-O-) in the structure of the said ring. Specifically, lactone-containing monocyclic groups such as a group in which one hydrogen atom has been removed from γ-butyrolactone, and groups in which one hydrogen atom has been removed from a lactone ring-containing bicycloalkane, tricycloalkane, or tetracycloalkane. And lactone-containing polycyclic groups.

As the substituent in the latter example, the same as those exemplified as the substituents which the above-described linear or branched alkyl group may have, a lower alkyl group, and the like can be mentioned.

In ^{addition, R 6 ', R 7'} , R 8 ' may be a combination of a linear or branched alkyl group and cyclic alkyl group.

As a combination of a linear or branched alkyl group and a cyclic alkyl group, a group in which a cyclic alkyl group is bonded as a substituent to a linear or branched alkyl group, a linear or branched chain as a substituent to a cyclic alkyl group The group to which an alkyl group is bonded, etc. are mentioned.

^{R 6 ', R 7',} R 8 ' linear aliphatic unsaturated hydrocarbon group in, for example, there may be mentioned a vinyl group, a propenyl group (allyl group), a butynyl group and the like.

^{R 6 ', R 7',} R 8 ' branched aliphatic unsaturated hydrocarbon group in, for example, and 1-methyl propenyl group, 2-propenyl group.

The linear or branched aliphatic unsaturated hydrocarbon group may have a substituent. Examples of the substituent include the same as those exemplified as the substituents which the linear or branched alkyl group may have.

R ^{7 ',} R ^8' in In, among the above, the lithographic properties, the resist in that the pattern shape is good, having from 1 to 15 carbon atoms in the linear or branched saturated hydrocarbon group, or cyclic having 3 to 20 carbon atoms Saturated hydrocarbon groups are preferred.

Examples of the alkyl group for R ^{1 "} to R ^3" include a C 1 to C 10 linear, branched or cyclic alkyl group. Among them, it is preferable to have 1 to 5 carbon atoms in terms of excellent resolution. Specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, n-pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, nonyl group, decyl group, etc. A methyl group is mentioned as a preferable thing from the point that it can be used, is excellent in resolution, and can be synthesized inexpensively.

In the alkyl group of R ^{1 "} to R ^3" , some or all of the hydrogen atoms are alkoxy groups, halogen atoms, hydroxyl groups, oxo groups (=O), aryl groups, alkoxyalkyloxy groups, alkoxycarbonylalkyloxy groups,- C (= O) -OR ⁶ or may ^{', -OC (= O) -R} 7', is substituted by -OR ^{8 '.} As an alkoxy group, a halogen atom, an aryl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, -C(=O)-OR ^6' , -OC(=O)-R ^7' , -OR ^8' , R ^{It is the} same as the substituent of the aryl group of ^{1 "} to R ^3" .

As the alkenyl group for R ^{1 "} to R ^{3 "} , for example, it is preferably 2 to 10 carbon atoms, more preferably 2 to 5, and still more preferably 2 to 4. Specifically, a vinyl group, a propenyl group (allyl group), a butynyl group, a 1-methylpropenyl group, a 2-methylpropenyl group, etc. are mentioned.

When any two of R ^{1 "} to R ^{3 "} are bonded to each other to form a ring with a sulfur atom in the formula, it is preferable to form a 3 to 10 membered ring including a sulfur atom, and a 5 to 7 membered ring It is particularly preferable to form.

Among the cation moieties in the compound represented by the above formula (b-c1), the ones specifically shown below are exemplified.

[Formula 6]

[Formula 7]

[Formula 8]

[In the formula, g1, g2, g3 represents a repeating number, g1 is an integer from 1 to 5, g2 is an integer from 0 to 20, and g3 is an integer from 0 to 20]

[Formula 9]

In formula (ca-1-47), R ^d is a substituent. As the substituent, the substituent exemplified in the description of the substituted aryl group (alkyl group, alkoxy group, alkoxyalkyloxy group, alkoxycarbonylalkyloxy group, halogen atom, hydroxyl group, oxo group (=O), aryl group, -C (=O)-OR ^{6 "} , -OC(=O)-R ^7" , -OR ^{8 "} ) can be mentioned.

In the formula (b-c2), R ^{5 ″} to R ^{6 ″} each independently represent an aryl group, an alkyl group, or an alkenyl group which may have a substituent.

Examples of the aryl group for R ^{5 ″} to R ^{6 ″ include} the same aryl groups for R ^{1 ″} to R ^{3 ″} .

Examples of the alkyl group for R ^{5 ″} to R ^{6 ″ include} the same alkyl groups for R ^{1 ″} to R ^{3 ″} .

Examples of the alkenyl group for R ^{5 ″} to R ^{6 ″ include} the same alkenyl groups for R ^{1 ″} to R ^{3 ″} .

Specific examples of the cation moiety in the compound represented by the formula (b-c2) include diphenyliodonium, bis(4-tert-butylphenyl)iodonium, and the like.

In the present specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid by irradiation (exposure) of radiation. Such an oxime sulfonate-based acid generator can be arbitrarily selected and used from those commonly used for chemically amplified resist compositions.

[Formula 10]

(In formula (B-1), R ³¹ and R ³² each independently represent an organic group)

The organic group of R ³¹ and R ³² is a group containing a carbon atom, and has an atom other than a carbon atom (e.g., a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (a fluorine atom, a chlorine atom, etc.)) You may have it.

As the organic group for R ³¹ , a linear, branched or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. The substituent is not particularly limited, and examples thereof include a fluorine atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms. Here, "having a substituent" means that some or all of the hydrogen atoms of the alkyl group or the aryl group are substituted with a substituent.

As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is still more preferable, C1-C6 is especially preferable, and C1-C4 is most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. In addition, a partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and a completely halogenated alkyl group means an alkyl group in which all of the hydrogen 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. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.

The aryl group has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferred. In addition, the partially halogenated aryl group means an aryl group in which some of the hydrogen atoms are replaced with halogen atoms, and the completely halogenated aryl group means an aryl group in which all of the hydrogen atoms are replaced with halogen atoms.

In particular, as R ³¹ , a C 1 to C 4 alkyl group or a C 1 to C 4 fluorinated alkyl group without a substituent is preferable.

As the organic group for R ³² , a linear, branched or cyclic alkyl group, aryl group or cyano group is preferable. Examples of the alkyl group and aryl group for R ³² include those similar to the alkyl group and aryl group exemplified in R ³¹ above.

Especially as R ³² , a cyano group, a C1-C8 alkyl group which does not have a substituent, or a C1-C8 fluorinated alkyl group is preferable.

As more preferable thing as an oxime sulfonate type acid generator, the compound represented by the following general formula (B-2) or (B-3) is mentioned.

[Formula 11]

[In formula (B-2), R ³³ is a cyano group, an alkyl group without a substituent, or a halogenated alkyl group. R ³⁴ is a group containing an aryl group. R ³⁴ alkyl group or a halogenated alkyl group and R ³⁵ of the combined may form a ring. R ³⁵ is an alkyl group having no substituent or a halogenated alkyl group]

[Formula 12]

[In formula (B-3), R ³⁶ is a cyano group, an alkyl group not having a substituent, or a halogenated alkyl group. R ³⁷ is a di or trivalent aromatic hydrocarbon group. R ³⁸ is an alkyl group having no substituent or a halogenated alkyl group. p" is 2 or 3.]

In the above general formula (B-2), the alkyl group or halogenated alkyl group having no substituent of R ³³ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms. .

As R ³³ , a halogenated alkyl group is preferable, and a fluorinated alkyl group is more preferable.

The fluorinated alkyl group for R ³³ is preferably 50% or more fluorinated, more preferably 70% or more fluorinated, and particularly preferably 90% or more fluorinated hydrogen atoms in the alkyl group.

^Examples of the group containing the aryl group of R ³⁴ include a hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. A group from which 1 is removed, and those containing a heteroaryl group in which some of the carbon atoms constituting the ring of these groups are substituted with a hetero atom such as an oxygen atom, a sulfur atom, and a nitrogen atom, etc. are mentioned. Among these, a fluorenyl group is preferable.

The group containing the aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group or an alkoxy group. The alkyl group or the halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. Further, the halogenated alkyl group is preferably a fluorinated alkyl group.

The alkyl group or halogenated alkyl group which does not have a substituent for R ³⁵ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.

As R ^{35, a} halogenated alkyl group is preferable and a fluorinated alkyl group is more preferable.

The fluorinated alkyl group for R ³⁵ is preferably 50% or more fluorinated hydrogen atoms of the alkyl group, more preferably 70% or more fluorinated, and 90% or more fluorinated one increases the strength of the generated acid. desirable. Most preferably, the hydrogen atom is a 100% fluorine-substituted fully fluorinated alkyl group.

In the general formula (B-3), examples of the alkyl group or halogenated alkyl group having no substituent for R ^{36 include} the same alkyl group or halogenated alkyl group having no substituent for R ³³ .

Examples of the divalent or trivalent aromatic hydrocarbon group for R ^{37 include} a group in which one or two hydrogen atoms have been further removed from the aryl group for R ³⁴ .

Examples of the alkyl group or halogenated alkyl group having no substituent for R ^{38 include} the same alkyl group or halogenated alkyl group having no substituent for R ³⁵ .

p" is preferably 2.

Specific examples of the oxime sulfonate acid generator include α-(p-toluenesulfonyloxyimino)-benzyl cyanide, α-(p-chlorobenzenesulfonyloxyimino)-benzyl cyanide, α-( 4-nitrobenzenesulfonyloxyimino)-benzyl cyanide, α-(4-nitro-2-trifluoromethylbenzenesulfonyloxyimino)-benzyl cyanide, α-(benzenesulfonyloxyimino)-4- Chlorobenzyl cyanide, α-(benzenesulfonyloxyimino)-2,4-dichlorobenzyl cyanide, α-(benzenesulfonyloxyimino)-2,6-dichlorobenzyl cyanide, α-(benzenesulfonyloxyimino) Mino)-4-methoxybenzyl cyanide, α-(2-chlorobenzenesulfonyloxyimino)-4-methoxybenzyl cyanide, α-(benzenesulfonyloxyimino)-thien-2-ylacetonitrile, α-(4-dodecylbenzenesulfonyloxyimino)-benzyl cyanide, α-[(p-toluenesulfonyloxyimino)-4-methoxyphenyl]acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) Mino)-4-methoxyphenyl]acetonitrile, α-(tosyloxyimino)-4-thienyl cyanide, α-(methylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(methylsulfur Phonyloxyimino)-1-cyclohexenylacetonitrile, α-(methylsulfonyloxyimino)-1-cycloheptenylacetonitrile, α-(methylsulfonyloxyimino)-1-cyclooctenylacetonitrile, α -(Trifluoromethylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(trifluoromethylsulfonyloxyimino)-cyclohexylacetonitrile, α-(ethylsulfonyloxyimino)-ethylaceto Nitrile, α-(propylsulfonyloxyimino)-propylacetonitrile, α-(cyclohexylsulfonyloxyimino)-cyclopentylacetonitrile, α-(cyclohexylsulfonyloxyimino)-cyclohexylacetonitrile, α- (Cyclohexylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(ethylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(isopropylsulfonyloxyimino)-1-cyclophene Tenylacetonitrile, α-(n-butylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(ethylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(isopropylsulfonyloxyimino) Mino)-1-cyclohexenylacetonitrile, α-(n-butylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(methyl Sulfonyloxyimino)-phenylacetonitrile, α-(methylsulfonyloxyimino)-p-methoxyphenylacetonitrile, α-(trifluoromethylsulfonyloxyimino)-phenylacetonitrile, α-(trifluoro Romethylsulfonyloxyimino)-p-methoxyphenylacetonitrile, α-(ethylsulfonyloxyimino)-p-methoxyphenylacetonitrile, α-(propylsulfonyloxyimino)-p-methylphenylacetonitrile, α-(methylsulfonyloxyimino)-p-bromophenylacetonitrile, and the like.

In addition, the oxime sulfonate acid generator disclosed in Japanese Patent Application Laid-Open No. Hei 9-208554 (paragraphs [0012] to [0014] of [Chemical Formulas 18] to [Chemical Formulas 19]), International Publication No. 04/074242 The oxime sulfonate acid generator disclosed in the heading (Examples 1 to 40 on pages 65 to 85) can also be preferably used.

Moreover, the following can be illustrated as a preferable thing.

[Formula 13]

Among the diazomethane-based acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis(isopropylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis (1,1-dimethylethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(2,4-dimethylphenylsulfonyl)diazomethane, and the like.

In addition, diazomethane-based acid generators disclosed in Japanese Laid-Open Patent Publication No. Hei 11-035551, Japanese Laid-Open Patent Publication No. Hei 11-035552, and Japanese Laid-Open Patent Publication No. Hei 11-035573 can also be preferably used.

Further, as poly(bissulfonyl)diazomethanes, for example, 1,3-bis(phenylsulfonyldiazomethylsulfonyl)propane disclosed in Japanese Laid-Open Patent Publication No. Hei 11-322707, 1,4-bis(phenylsulfonyldiazomethylsulfonyl)butane, 1,6-bis(phenylsulfonyldiazomethylsulfonyl)hexane, 1,10-bis(phenylsulfonyldiazomethylsulfonyl)decane , 1,2-bis(cyclohexylsulfonyldiazomethylsulfonyl)ethane, 1,3-bis(cyclohexylsulfonyldiazomethylsulfonyl)propane, 1,6-bis(cyclohexylsulfonyldiazomethyl) Sulfonyl) hexane, 1,10-bis (cyclohexyl sulfonyl diazomethylsulfonyl) decane, etc. are mentioned.

As for the component (B), the above-described acid generator may be used alone, or two or more types may be used in combination.

When the brush agent contains the component (B), the content of the component (B) in the brush agent is preferably 0.5 to 30 parts by mass relative to 100 parts by mass of the component (A), and when the component (B) is a thermal acid generator, , 1 to 20 parts by mass is more preferable. When the component (B) is a photoacid generator, 0.5 to 30 parts by mass is preferable, and 1 to 20 parts by mass is more preferable. By setting it as the above range, the effect of the present invention can be sufficiently obtained, and if the content of the component (B) is equal to or greater than the lower limit, the content of the component (A) in the brush does not decrease, which is preferable.

In the brush composition of the present invention, additives with miscibility as desired, for example, additional resins for improving the performance of the layer made of brush, surfactants for improving coating properties, dissolution inhibitors, plasticizers, stabilizers , A colorant, an antihalation agent, a dye, a sensitizer, a base proliferative agent, a basic compound, and a nitrogen-containing basic compound such as imidazole may be appropriately added and contained.

[Organic solvents; (S) component]

The brush formulation of the present invention can be produced by dissolving a material in an organic solvent (hereinafter, also referred to as "(S) component").

As the (S) component, any one or two or more types of any one or two or more solvents known as solvents for film compositions containing resin as a main component in the past can be used as long as it can dissolve each component to be used as a uniform solution. You can choose and use it.

Lactones such as γ-butyrolactone; Ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; Polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; Compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, monomethyl ether, monoethyl ether of the polyhydric alcohols or compounds having the ester bond, Derivatives of polyhydric alcohols, such as monoalkyl ethers such as monopropyl ether and monobutyl ether, or compounds having an ether bond such as monophenyl ether [In particular, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) is preferable]; Cyclic ethers such as dioxane, esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; Anisole, ethylbenzyl ether, cresylmethyl ether, diphenyl ether, dibenzyl ether, phenethyl, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene Aromatic organic solvents, such as, etc. are mentioned.

These organic solvents may be used alone or as a mixed solvent of two or more.

Among them, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, and EL are preferred.

Further, a mixed solvent in which PGMEA and a polar solvent are mixed is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility of PGMEA and the polar solvent, but it is preferably in the range of 1:9 to 9:1, more preferably 2:8 to 8:2. Do. For example, in the case of blending EL as a polar solvent, the mass ratio of PGMEA:EL is preferably 1:9 to 9:1, more preferably 2:8 to 8:2. In addition, in the case of blending PGME as a polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, still more preferably 3:7 to 7 : 3. In addition, when mixing PGME and cyclohexanone as a polar solvent, the mass ratio of PGMEA: (PGME + cyclohexanone) is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, More preferably, they are 3:7 to 7:3.

In addition, as the component (S), PGMEA, EL, or a mixed solvent of the PGMEA and a polar solvent and a mixed solvent of γ-butyrolactone are also preferable. In this case, as the mixing ratio, the mass ratio of the former and the latter is preferably 70:30 to 95:5.

The amount of the component (S) is not particularly limited, and is a concentration applicable to a substrate or the like, and is appropriately set depending on the thickness of the coating film, but in general, the solid content concentration of the brush is 1 to 20% by mass, preferably 2 to 15. It is used so that it may fall within the range of mass%.

≪How to form a pattern≫

The second aspect of the present invention is a step of applying the brush of the first aspect of the present invention on a substrate to form a layer made of the brush, and a block in which a plurality of types of polymers are bonded on the layer made of the brush. It is a pattern formation method characterized by including a step of forming a layer containing a copolymer and a step of phase-separating the layer containing the block copolymer. Hereinafter, the pattern formation method of the present invention will be described in detail with reference to FIG. 1. However, the present invention is not limited to this.

[Process of forming a layer made of the brush by applying the brush on a substrate]

In the pattern formation method of the present invention, first, the brush is applied on a substrate to form a layer made of the brush.

<Substrate>

The type of the substrate 1 is not particularly limited as long as it is capable of applying a solution containing a block copolymer on its surface, or as long as the brushing agent according to the present invention can be applied. For example, substrates made of metals such as silicon, copper, chromium, iron, aluminum, inorganic substances such as glass, titanium oxide, silica, mica, etc., substrates having a nitride oxide film such as SiON, acrylic plates, polystyrene, cellulose, cellulose acetate And a substrate made of an organic compound such as a phenol resin.

In addition, the size and shape of the substrate 1 used in the present invention are not particularly limited. The substrate 1 does not necessarily have a smooth surface, and substrates of various materials and shapes can be appropriately selected. For example, it can be used in various shapes, such as a substrate having a curved surface, a flat plate having an uneven surface, and a flake shape.

Moreover, an inorganic and/or organic film may be formed on the surface of the substrate 1. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). An organic antireflection film (organic BARC) is mentioned as an organic film.

The inorganic film can be formed by, for example, applying an inorganic antireflection film composition such as a silicon material on a substrate and firing.

For the organic film, for example, a material for forming an organic film in which a resin component constituting the film is dissolved in an organic solvent is applied on a substrate with a spinner or the like, and is preferably 200 to 300°C, preferably 30 to 300 seconds. , More preferably, it can be formed by baking treatment under heating conditions for 60 to 180 seconds. The material for forming an organic film used at this time does not necessarily require sensitivity to light or electron beams, such as a resist film, and may or may not have the sensitivity. Specifically, a resist or resin generally used in the manufacture of a semiconductor device or a liquid crystal display device can be used.

In addition, by etching the organic film using a pattern made of a block copolymer, the organic film forming material can form an organic film capable of etching, particularly dry etching, so that the pattern can be transferred to the organic film and an organic film pattern can be formed. It is preferable that it is a material. Among them, it is preferable that it is a material capable of forming an organic film capable of etching such as oxygen plasma etching. As such a material for forming an organic film, a material conventionally used to form an organic film such as organic BARC may be used. For example, the ARC series manufactured by Brewer Sciences, the AR series manufactured by Rom & Haas, and the SWK series manufactured by Tokyo Oka Industries, etc. can be mentioned.

Before the layer 2 made of the brush of the first aspect of the present invention is formed on the substrate, the surface of the substrate 1 may be cleaned in advance. By cleaning the surface of the substrate, there may be a case where the application of the brush can be satisfactorily performed.

As the cleaning treatment, a conventionally known method can be used, for example, oxygen plasma treatment, ozone oxidation treatment, acid alkali treatment, chemical modification treatment, and the like.

The method of forming the layer 2 made of the brush by applying the brush of the first aspect on the substrate 1 is not particularly limited, and may be formed by a conventionally known method.

For example, the layer 2 made of the brush can be formed by applying a brushing agent on the substrate 1 by a conventionally known method such as spin coat or spinner to form a coating film and drying it. .

As a method of drying the coating film, the organic solvent contained in the brush may be volatilized, and for example, a method of baking may be mentioned.

The baking temperature is preferably 80 to 300°C, more preferably 100 to 270°C, and still more preferably 120 to 250°C. The baking time is preferably from 30 to 500 seconds, and more preferably from 60 to 240 seconds.

In the present invention, a step of washing an uncrosslinked portion in the coating film may be included by applying a brush to form a coating film and then rinsing with a rinse liquid such as a solvent. By forming the layer (2) made of a brush by the cleaning step, since uncrosslinked portions and the like can be removed, the affinity with at least one polymer (block) constituting the block copolymer is improved, and the substrate surface It becomes easy to form a phase-separated structure composed of a lamellar structure or a cylinder structure oriented in a direction perpendicular to the? In addition, the rinse liquid should just dissolve the uncrosslinked part, and solvents, such as PGMEA, PGME, EL, or a commercially available thinner liquid can be used. Further, after the washing step, in order to volatilize the rinse liquid, a drying step such as post-baking at about 80 to 150 degrees may be performed.

By forming a layer 2 made of a base material on the surface of the substrate 1, the surface of the substrate 1 is neutralized, so that only a phase made of a specific block among the layers 3 made of a block copolymer formed on the upper layer thereof is Contact with the substrate surface can be suppressed. As a result, a cylinder structure, a lamella structure, a dot structure, a gyroid structure, a spherical dispersion structure, etc. are formed freely oriented with respect to the substrate surface by phase separation of the layer (3) containing the block copolymer. It becomes possible to do.

[Process 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]

The method of forming the layer (3) containing a block copolymer to which a plurality of types of polymers are bonded on the layer (2) made of the brush is not particularly limited, for example, a composition containing a block copolymer , It can be formed by coating on the layer (2) made of a brush. As a coating method, the same thing as a base agent is mentioned.

In the present invention, the thickness of the layer (3) containing the block copolymer may be a thickness sufficient to cause phase separation, and the lower limit of the thickness is not particularly limited, but the structural period size of the phase separation structure to be formed, Considering the uniformity of the nanostructure and the like, it is preferably 5 nm or more, and more preferably 10 nm or more.

(Composition containing 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 type are bonded are bonded. The types of blocks constituting the block copolymer may be two or three or more. In the present invention, the plurality of types of blocks constituting the block copolymer are not particularly limited as long as it is a combination in which phase separation occurs, but a combination of blocks that are incompatible with each other is preferable. In addition, it is preferable that a phase composed of at least one type of block among a plurality of types of blocks constituting the block copolymer is a combination capable of being selectively removed more easily than a phase composed of other types of blocks.

As a block copolymer, for example,

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 substitution) acrylic acid ester are bonded together;

Block copolymers in which a block of structural units derived from styrene or a derivative thereof and a block of structural units derived from siloxane or a derivative thereof are bonded together;

• A block copolymer in which a block of structural units derived from alkylene oxide and a block of structural units derived from (α substitution) acrylic acid esters are bonded to each other.

Constituent units derived from styrene or a derivative thereof, and constituent units derived from (α-substituted) acrylic acid esters are the same as described above.

Examples of the siloxane derivatives include dimethylsiloxane, diethylsiloxane, diphenylsiloxane, and methylphenylsiloxane.

Examples of the alkylene oxide include ethylene oxide, propylene oxide, isopropylene oxide, and butylene oxide.

Among them, 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)acrylic acid ester.

Specifically, polystyrene-polymethylmethacrylate (PS-PMMA) block copolymer, polystyrene-polyethylmethacrylate block copolymer, polystyrene-(poly-t-butylmethacrylate) block copolymer, polystyrene-poly Methacrylic acid block copolymer, polystyrene-polymethylacrylate block copolymer, polystyrene-polyethylacrylate block copolymer, polystyrene-(poly-t-butylacrylate) block copolymer, polystyrene-polyacrylic acid block copolymer, etc. And, in particular, it is preferable to use a PS-PMMA block copolymer.

The mass average molecular weight (Mw) of each polymer constituting the block copolymer (based on polystyrene conversion by gel permeation chromatography) is not particularly limited as long as it is a size capable of causing phase separation, but is preferably 5000 to 500000, and 5000 400000 are more preferable, and 5000-300000 are still more preferable.

Moreover, as for the dispersion degree (Mw/Mn) of a block copolymer, 1.0-3.0 are preferable, 1.0-1.5 are more preferable, and 1.0-1.2 are still more preferable. Moreover, Mn represents a number average molecular weight.

In the composition containing the block copolymer, in addition to the above block copolymer, additionally compatible additives as desired, for example, additional resins for improving the performance of the layer made of brush, and surfactants for improving coating properties. , A dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an anti-halation agent, a dye, a sensitizer, a base growth agent, a basic compound, and the like can be appropriately added and contained.

・Organic solvent

A composition containing a block copolymer can be prepared by dissolving the block copolymer in an organic solvent. As the organic solvent, the same organic solvent as the above-described component (S) can be used as an organic solvent that can be used for a brush.

The amount of the organic solvent used in the composition containing the block copolymer is not particularly limited, and it is a concentration that can be applied and is appropriately set depending on the thickness of the coating film, but in general, the solid content concentration of the block copolymer is 0.2 to 70% by mass, Preferably, it is used so as to fall within the range of 0.2 to 50% by mass.

[Step of phase-separating a layer containing a block copolymer]

Phase separation of the layer (3) containing the block copolymer is performed by thermally treating the substrate (1) provided with the layer (2) made of a brush, on which the layer (3) containing the block copolymer is formed, and in a subsequent step. By selective removal of the block copolymer of, at least a portion of the substrate surface is exposed to form a phase separation structure. It is preferable to perform the heat treatment at a temperature equal to or higher than the glass transition temperature of the block copolymer to be used and lower than the thermal decomposition temperature. For example, when the block copolymer is PS-PMMA (Mw: 40k-20k), it is preferable to perform heat treatment at 180 to 270°C for 30 to 3600 seconds.

In addition, the heat treatment is preferably performed in a gas having low reactivity such as nitrogen.

<arbitrary process>

[Step of selectively removing a phase consisting of at least one type of block among a plurality of types of blocks constituting the block copolymer from among the layer containing the block copolymer]

Of the layer (3) containing the block copolymer, a pattern may be formed by selectively removing a phase (3a) comprising at least one type of block from among a plurality of types of blocks constituting the block copolymer.

In the following, among blocks constituting the block copolymer, a block that is not selectively removed in a subsequent step is referred to as a P _A block, and a block that is selectively removed is referred to as a P _B block. For example, after the layer containing the PS-PMMA block copolymer is phase-separated, the layer made of PMMA is selectively removed by subjecting the layer to oxygen plasma treatment or hydrogen plasma treatment. In this case, PS is a P _A block and PMMA is a P _B block.

Subsequently, at least a part of the block in the phase consisting of P _B blocks is selectively removed (lower molecular weight) from the layer containing the block copolymer on the substrate after the phase separation structure has been formed. By selectively removing a part of the P _B block in advance, the solubility in the developer is increased, and as a result, the phase composed of the P _B block becomes easier to selectively remove than the phase composed of the P _A block.

This selective removing process, if the process to decompose and remove standing P _B blocks do not affect the P _A block is not particularly limited, the type of P _A block and P _B block from the method used for the resin film removed It can be appropriately selected and implemented according to. Further, in the case of the neutralizing film is previously formed on the substrate surface, the same is removed and the film is also made of the art neutralization P _B block. Examples of such removal treatment include oxygen plasma treatment, ozone treatment, UV irradiation treatment, thermal decomposition treatment, and chemical decomposition treatment.

The substrate on which the pattern (3b) was formed by phase separation of the block copolymer layer (3) as described above may be used as it is, but the shape of the polymer nanostructure on the substrate may be changed by performing additional heat treatment. have. The temperature of the heat treatment is preferably performed at a temperature equal to or higher than the glass transition temperature of the block copolymer to be used and lower than the thermal decomposition temperature. In addition, the heat treatment is preferably performed in a gas having low reactivity such as nitrogen.

[Guide pattern formation process]

In the pattern formation method of the present invention, after the [step of applying the brush on a substrate to form a layer made of the brush], a block copolymer in which a plurality of types of polymers are bonded is added to the layer made of the brush. Step of forming a containing layer] Before, a guide pattern in which a pattern is formed on the layer 2 made of a brush may be formed in advance. Thereby, it becomes possible to control the arrangement structure of the phase separation structure according to the shape and surface characteristics of the guide pattern. For example, in the absence of a guide pattern, even if it is a block copolymer in which a random fingerprint phase-separated structure is formed, a phase-separated structure oriented along the groove is obtained by introducing a groove structure of a resist film on the substrate surface. A guide pattern may be introduced using this principle. Further, since the surface of the guide pattern has affinity with any polymer constituting the block copolymer, it is possible to easily form a phase-separated structure composed of a lamella structure or a cylinder structure oriented in a direction perpendicular to the substrate surface.

Specifically, for example, a resist composition is applied on the surface of a substrate with a spinner or the like, and pre-baking (post-applied baking (PAB)) is performed for 40 to 120 seconds, preferably 60 under a temperature condition of 80 to 150°C. After carrying out for -90 seconds, for example, after selectively exposing ArF excimer laser light through a desired mask pattern by an ArF exposure apparatus or the like, under a temperature condition of 80 to 150°C, PEB (heating after exposure) was 40 It is carried out for -120 seconds, Preferably it is 60-90 seconds. Subsequently, this is developed using an alkali developer, for example, 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH) aqueous solution, and rinsed with water preferably using pure water and dried. In addition, in some cases, a bake treatment (post bake) may be performed after the development treatment. In this way, a guide pattern faithful to the mask pattern can be formed.

It is preferable that the height of the guide pattern from the surface of the substrate (or the surface of the neutralization film) is equal to or greater than the thickness of the layer containing the block copolymer formed on the surface of the substrate. The height of the guide pattern from the substrate surface (or the surface of the neutralization film) can be appropriately adjusted by, for example, the film thickness of the resist film formed by applying a resist composition for forming the guide pattern.

The resist composition for forming the guide pattern can be suitably selected from among resist compositions or modifications thereof that are generally used for forming a resist pattern and have affinity with any polymer constituting the block copolymer. The resist composition may be any of a positive resist composition forming a positive pattern in which an exposed portion is dissolved and removed, and a negative resist composition forming a negative pattern in which an unexposed portion is dissolved and removed, but the negative resist composition is desirable. The negative resist composition contains, for example, an acid generator and a base component whose solubility in a developer containing an organic solvent decreases due to the action of an acid, and the base component is decomposed by the action of an acid. A resist composition containing a resin component having a structural unit whose polarity is increased is preferred.

Further, after pouring a solution of the block copolymer onto the surface of the substrate on which the guide pattern is formed, heat treatment is performed to cause phase separation. For this reason, it is preferable that the resist composition for forming the guide pattern is capable of forming a resist film having excellent solvent resistance and heat resistance.

Example

Hereinafter, the present invention will be described in more detail by examples, but the present invention is not limited to the following examples.

[Preparation of the lower body agent-1]

The following monomers (1) to (3) were synthesized at the molar ratio shown in Table 1 to prepare resins 1 to 5, and resins 1 to 5 were each dissolved in propylene glycol monomethyl ether acetate (PGMEA), and solid content concentration was 0.4% by mass The base agents 1-5 were prepared.

[Formula 14]

Examples 1 to 8, Comparative Examples 1 to 12

On an 8-inch silicon wafer, an organic anti-reflection film composition "ARC29A" (trade name, manufactured by Brewer Science) was applied using a spinner, and then baked on a hot plate at 205°C for 60 seconds and dried to obtain a film thickness of 82 nm. An organic antireflection film was formed.

Subsequently, on the organic a/P antireflection film, each brushing agent shown in Table 2 was applied using a spinner, fired at each temperature shown in Table 2 for 1 minute, dried, and treated and dried with PGMEA to make the film thickness A layer made of a 10 nm brush was formed on the substrate.

Water was dripped on the surface of the base material, and the contact angle (static contact angle) was measured using DROP MASTER-700 (product name, manufactured by Kyowa Interface Science Co., Ltd.) (measurement of contact angle: water 2 μl). This measured value is referred to as "contact angle (°)", and the results are shown in Tables 2 to 3.

Then, block copolymer 1 of PS-PMMA (Mw 42,400, PS/PMMA composition ratio (molar ratio) 55/45, dispersion degree 1.07, period 26 nm) or block copolymer 2 (Mw 42,400, PS) to cover the brush part. A PGMEA solution (2 mass%) having a /PMMA composition ratio (molar ratio) of 75/25, a dispersion degree of 1.07, and a cycle of 26 nm) was spin-coated (rotation speed: 1500 rpm, 60 seconds). The substrate to which the PS-PMMA block copolymer was applied was annealed by heating at 240° C. for 60 seconds under a nitrogen stream to form a phase separation structure.

As a result, in Examples 1 to 8 and Comparative Examples 1 to 12, it was possible to manufacture a structure including a phase separation structure on a brush.

In any of the examples, a lamella 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 the phase separation was formed was subjected to oxygen plasma treatment (200 mL/min, 40 Pa, 40° C., 200 W, for 20 seconds) using TCA-3822 (manufactured by Tokyo Oka Industries) to selectively select a phase made of PMMA. It removed, and the surface of the obtained board|substrate was observed with a scanning electron microscope SEMSU8000 (manufactured by Hitachi High-Technology). A uniform pattern (vertical lamella pattern or cylinder pattern) is observed, A, brushing agent where a uniform pattern (vertical lamella pattern or cylinder pattern) is not formed is observed B, and a uniform pattern (vertical lamella pattern or cylinder The brush composition in which the pattern) was not observed was evaluated as C. The results are shown in Tables 2-3.

As shown in the above results, the brush composition of the present invention has a wide temperature margin of 180°C to 250°C, and a lamella pattern and/or a cylinder pattern could be formed by using the brush composition of the present invention.

[Preparation of the lower body agent-2]

The monomers (1) to (3) were synthesized at a molar ratio shown in Table 4 to obtain Resins 6 to 9. About the obtained resins 6-9, it was made to melt|dissolve in PGMEA by the distribution shown in Table 5, and the brushing agents 6-17 of the solid content concentration 0.4 mass% were obtained. The molar ratio of the monomers (1) to (3) (after resin blending) in the brush is also indicated in Table 5.

Examples 9 to 32

On an 8-inch silicon wafer, each brushing agent shown in Table 6 was applied using a spinner, fired for 1 minute at each temperature shown in Table 6, dried, and treated with PGMEA and dried to have a film thickness of about 7 nm. A layer made of a brush was formed on the substrate.

Water was dripped on the surface of the base material, and the contact angle (static contact angle) was measured using DROP MASTER-700 (product name, manufactured by Kyowa Interface Science Co., Ltd.) (measurement of contact angle: water 2 μl). This measured value was taken as the "contact angle (°)", and the results are shown in Table 6.

Subsequently, a PGMEA solution (2 mass%) of PS-PMMA block copolymer 1 (Mw 149000, PS/PMMA composition ratio (molar ratio) 72/28, dispersion degree 1.08, period 52 nm) was spun so as to cover the brush part. It was coated (rotation speed 1500 rpm, 60 seconds). The substrate to which the PS-PMMA block copolymer was applied was annealed by heating at 240° C. for 60 seconds under a nitrogen stream to form a phase separation structure.

The substrate on which the phase separation was formed was subjected to oxygen plasma treatment (200 mL/min, 40 Pa, 40° C., 200 W, for 20 seconds) using TCA-3822 (manufactured by Tokyo Oka Industries) to selectively select a phase made of PMMA. After removal, the surface of the obtained substrate was observed with a scanning electron microscope SU8000 (manufactured by Hitachi High-Technology).

◎ that the uniform pattern (vertical cylinder pattern) is formed, the vertical cylinder pattern is formed, but the holes (2 to 3) are connected in part ○, the vertical cylinder pattern is formed, but the hole (5) is partially -10 pieces) were evaluated as △. Table 6 shows the results.

Further, in the pattern formation step, the shape of the vertical cylinder pattern formed in the same manner was evaluated in the same manner except that a SiON substrate was used instead of a silicon wafer. Table 6 shows the results.

From the results of Table 6, it was confirmed that the brush formulation according to the present invention had no substrate dependence and a wide temperature margin. In a ternary resin composed of a structural unit having an aromatic group, a structural unit having a hydroxyalkyl group, and a structural unit not having an aromatic group and a hydroxyalkyl group, the structural unit having an aromatic group is 78 mol% or more and 90 mol% or less In addition, when it became 6 mol% or less of structural units which have a hydroxyalkyl group, it was confirmed that a favorable cylinder pattern was obtained.

In the above, preferred embodiments of the present invention have been described, but the present invention is not limited to these examples. Additions, omissions, substitutions, and other changes of configurations are possible without departing from the spirit of the present invention. The invention is not limited by the foregoing description, but only by the scope of the appended claims.

Claims (3)

As a brushing agent used to phase-separate a layer containing a block copolymer in which a plurality of types of blocks formed on a substrate are bonded,
It contains a resin component, and the resin component,
A structural unit having an aromatic group, and
A structural unit having a hydroxyalkyl group, and
It contains a structural unit that does not have an aromatic group and a hydroxyalkyl group,
The ratio of the structural unit having an aromatic group is 78 mol% or more and 90 mol% or less, and the ratio of the structural unit having the hydroxyalkyl group is 6 mol% or less with respect to all the structural units constituting the resin component. Article (except for those containing a resin component containing an acid-decomposable group). delete Applying the brush according to claim 1 on a substrate to form a layer made of the brush,
Forming a layer containing a block copolymer to which a plurality of types of polymers are bonded on the layer made of the brush,
A pattern formation method comprising a step of phase-separating a layer containing the block copolymer.

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