JP6741540B2 - Method for controlling surface properties of substrate - Google Patents

Description

The present invention relates to a method for controlling surface properties of a substrate.

In the lithographic technique, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed to radiation such as light or an electron beam through a mask on which a predetermined pattern is formed. Then, a step of forming a resist pattern having a predetermined shape on the resist film is performed by performing development processing. In addition, after that, a step of forming a pattern by performing an etching process on the substrate on which the resist pattern is formed by using the resist pattern as a mask is performed.
A resist material in which the exposed portion changes to a characteristic that dissolves in a developing solution is called a positive type, and a resist material in which the exposed portion changes to a characteristic that does not dissolve in a developing solution is called a negative type.
2. Description of the Related Art In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, pattern miniaturization has been rapidly progressing due to the progress of lithography technology. As a method of miniaturization, generally, the wavelength of an exposure light source is shortened (increased in energy). Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but now, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. Further, EB (electron beam), EUV (extreme ultraviolet ray), X-ray, etc. having a shorter wavelength (high energy) than these excimer lasers are also being studied.

As the wavelength of the exposure light source is shortened, the resist material is required to have improved lithographic characteristics such as sensitivity to the exposure light source and resolution capable of reproducing a pattern having a fine dimension. A chemically amplified resist is known as a resist material satisfying such requirements. As the chemically amplified resist, a composition containing a base material component whose solubility in an alkali developing solution is changed by the action of an acid and an acid generator component which generates an acid upon exposure is generally used. For example, in the case of a positive type chemically amplified resist composition, as the base material component, a material whose solubility in a base-made alkaline developing solution is increased by the action of an acid is used.
Conventionally, a resin (base resin) is mainly used as a base material component of a chemically amplified resist composition. In the case of the positive type, as the base resin, a resin whose solubility in an alkali developing solution is increased by the action of an acid is generally used.
Currently, as a base resin for a chemically amplified resist composition used in ArF excimer laser lithography, etc., it has a structural unit derived from a (meth)acrylic acid ester in its main chain because of its excellent transparency in the vicinity of 193 nm. A resin (acrylic resin) is the mainstream (see, for example, Patent Document 1).

Here, in the present specification, “(meth)acrylic acid” means one or both of acrylic acid having a hydrogen atom bonded to the α-position and methacrylic acid having a methyl group bonded to the α-position. The “(meth)acrylic acid ester” means one or both of an acrylic acid ester having a hydrogen atom bonded to the α-position and a methacrylic acid ester having a methyl group bonded to the α-position. The “(meth)acrylate” means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methacrylate having a methyl group bonded to the α-position.

In addition, a pattern forming method for suppressing peeling of a resist pattern from a substrate for the purpose of improving pattern resolution, specifically, epoxidation by epoxidizing 1,2-polybutadiene (weight average molecular weight of about 150,000) Using a solution of 1,2-polybutadiene dissolved in an organic solvent, the solution is applied on a silicon wafer to form a thin film (surface modification layer) of about 10Å, and then baked at 130°C. Then, a pattern forming method has been proposed in which a resist pattern (line width: 1000 to 1500 nm) is formed on a silicon wafer having the surface modified layer, and then an etching process is performed (see Patent Document 2).

JP, 2003-241385, A JP-A-56-16129

With the progress of finer patterns, in the lithography technology, in order to improve various lithography characteristics, the surface of the substrate such as film thickness, in-plane uniformity, surface roughness (Ra), adhesion, contact angle, etc. It is required to control the characteristics. Conventionally, the adhesion of a resist pattern to a substrate or the like has been improved by a method of subjecting a substrate such as a silicon wafer or the like to, for example, hexamethyldisilazane (HMDS) treatment or providing an organic antireflection film. ..
However, for example, a support obtained by subjecting a silicon wafer to a HMDS treatment or a surface modification layer formed in the same manner as in the method of Patent Document 2 has a film thickness of the support surface, a surface roughness, a substrate There was room for improvement in the surface properties of the support such as adhesion and contact angle. Further, in the conventional method for treating the surface of the substrate, it is difficult to control the surface physical properties of the support because the surface physical properties change depending on the type of the substrate.
In addition, when the surface modification layer is formed on the silicon wafer and a resist pattern is further formed on the support that has been baked at 130° C. and etching is performed, the edges of the resist pattern peel off from the support. There was an easy problem.

The present invention has been made in view of the above circumstances and provides a method for controlling the surface physical properties of a substrate that can obtain desired surface physical properties independently of the type of the substrate and can suppress pattern peeling. It is an issue.

A first aspect of the present invention is a surface of a substrate including a coating step of coating an epoxy group-containing resin on the surface of a substrate containing at least two metals on the surface, and a baking step of baking the substrate. It is a method of controlling physical properties.

According to the present invention, it is possible to provide a method for controlling desired surface physical properties of a substrate that can obtain desired surface physical properties without depending on the type of the substrate and can suppress pattern peeling.

In the present specification and claims, "aliphatic" is defined as a concept relative to aromatic and means a group, compound or the like having no aromaticity.
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
Unless otherwise specified, the “alkylene group” includes linear, branched, and cyclic divalent saturated hydrocarbon groups.
The “halogenated alkyl group” is a group in which a part or all of hydrogen atoms of an alkyl group are substituted with a halogen atom, and the halogen atom includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
The “fluorinated alkyl group” or “fluorinated alkylene group” refers to a group in which some or all of the hydrogen atoms of the alkyl group or alkylene group are substituted with fluorine atoms.
The “structural unit” means a monomer unit (monomer unit) that constitutes a high molecular compound (resin, polymer, copolymer).
Be referred to as a "may have a substituent", the case of replacing a hydrogen atom (-H) a monovalent group, methylene group - when substituting a divalent radical (-CH ₂₎ And both are included.
“Exposure” is a concept that includes all radiation irradiation.

The “structural unit derived from an acrylate ester” means a constitutional unit formed by cleavage of an ethylenic double bond of an acrylate ester.
The term "acrylate ester" is a compound in which the hydrogen atom of the carboxyl group terminal of acrylic acid _(CH 2 = CH-COOH) has been substituted with an organic group.
In the acrylate ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The substituent (R ^α0 ) for substituting the hydrogen atom bonded to the carbon atom at the α-position is an atom or a group other than a hydrogen atom, and is, for example, an alkyl group having 1 to 5 carbon atoms or a halogenated group having 1 to 5 carbon atoms. An alkyl group etc. are mentioned. In addition, itaconic acid diesters in which the substituent (R ^α0 ) is substituted with a substituent containing an ester bond, and α-hydroxy acrylic esters in which the substituent (R ^α0 ) is substituted with a hydroxyalkyl group or a group in which the hydroxyl group is modified are also included. Shall be included. The α-position carbon atom of the acrylic ester is the carbon atom to which the carbonyl group of acrylic acid is bonded, unless otherwise specified.
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, the acrylic ester and the α-substituted acrylic ester may be collectively referred to as “(α-substituted) acrylic ester”.

The “structural unit derived from acrylamide” means a structural unit formed by cleavage of the ethylenic double bond of acrylamide.
In acrylamide, a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and one or both hydrogen atoms of an amino group of acrylamide may be substituted with a substituent. The carbon atom at the α-position of acrylamide refers to the carbon atom to which the carbonyl group of acrylamide is bonded, unless otherwise specified.
As the substituent for substituting the hydrogen atom bonded to the carbon atom at the α-position of acrylamide, the same substituents as the substituents at the α-position (substituent (R ^α0 )) in the above α-substituted acrylate ester can be used. Can be mentioned.

The “structural unit derived from hydroxystyrene” means a structural unit formed by cleavage of the ethylenic double bond of hydroxystyrene. The “structural unit derived from a hydroxystyrene derivative” means a structural unit formed by cleavage of the ethylenic double bond of the hydroxystyrene derivative.
The term “hydroxystyrene derivative” is a concept including hydroxystyrene in which the hydrogen atom at the α-position is substituted with another substituent such as an alkyl group and a halogenated alkyl group, and derivatives thereof. As the derivatives thereof, those obtained by substituting the hydrogen atom of the hydroxyl group of hydroxystyrene, which may be substituted by the substituent at the α-position, with an organic group; Examples thereof include those in which a substituent other than a hydroxyl group is bonded to the benzene ring of good hydroxystyrene. The α-position (carbon atom at the α-position) refers to the carbon atom to which the benzene ring is bonded, unless otherwise specified.
Examples of the substituent for substituting the hydrogen atom at the α-position of hydroxystyrene include the same ones as the substituents at the α-position in the above α-substituted acrylate ester.

The “constituent unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative” means a constituent unit formed by cleavage of the ethylenic double bond of vinylbenzoic acid or a vinylbenzoic acid derivative.
The term “vinyl benzoic acid derivative” includes vinyl benzoic acid having the α-position hydrogen atom substituted with another substituent such as an alkyl group and a halogenated alkyl group, and a derivative thereof. Those derivatives include those in which the hydrogen atom of the carboxy group of vinylbenzoic acid, which may have a hydrogen atom at the α-position substituted by an organic group,; the hydrogen atom at the α-position is substituted by a substituent. And the like. Examples thereof include vinyl benzoic acid having a benzene ring to which a substituent other than a hydroxyl group and a carboxy group is bonded. The α-position (carbon atom at the α-position) refers to the carbon atom to which the benzene ring is bonded, unless otherwise specified.

"Styrene" is a concept including styrene and styrene in which the hydrogen atom at the α-position is substituted with another substituent such as an alkyl group or a halogenated alkyl group.
The term “styrene derivative” is a concept including styrene in which the hydrogen atom at the α-position is substituted with another substituent such as an alkyl group and a halogenated alkyl group, and derivatives thereof. Examples of these derivatives include those in which a substituent is bonded to the benzene ring of hydroxystyrene in which the hydrogen atom at the α-position may be substituted. The α-position (carbon atom at the α-position) refers to the carbon atom to which the benzene ring is bonded, unless otherwise specified.
The "structural unit derived from styrene" and the "structural unit derived from styrene derivative" mean a structural unit formed by cleavage of an ethylenic double bond of styrene or a styrene derivative.

The alkyl group as the α-position substituent is preferably a linear or branched alkyl group, specifically, an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group , N-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.
Further, the halogenated alkyl group as the α-position substituent is specifically a group in which a part or all of the hydrogen atoms of the above-mentioned “alkyl group as the α-position substituent” is substituted with a halogen atom. To be Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable.
Specific examples of the hydroxyalkyl group as the α-position substituent include groups in which a part or all of the hydrogen atoms of the above-mentioned “alkyl group as the α-position substituent” are substituted with hydroxyl groups. 1-5 are preferable and, as for the number of the hydroxyl groups in this hydroxyalkyl group, 1 is the most preferable.

<Method of controlling surface properties of substrate>
The method of controlling the surface physical properties of the substrate according to the present embodiment includes a coating step of coating an epoxy group-containing resin on the surface of a substrate containing at least two metals on the surface, and a baking step of baking the substrate, including.
Hereinafter, in this embodiment, a material containing an epoxy group-containing resin may be referred to as a “surface modification material”. Further, the film formed in the baking step may be referred to as a "surface modified layer".

[Coating process]
In the coating step, the epoxy group-containing resin is coated on the surface of the substrate containing at least two kinds of metals on the surface.
The method of applying the epoxy group-containing resin to the surface of the substrate is not particularly limited, and examples thereof include conventionally known methods such as spin coating and slit coating.

(substrate)
The substrate is not particularly limited as long as it contains at least two kinds of metals on its surface, and a conventionally known substrate can be used. For example, a substrate for electronic parts, a substrate on which a predetermined wiring pattern is formed, etc. can be exemplified. More specifically, Si-containing substrates such as Si substrates, SiO ₂ substrates, and SiON substrates; substrates made of metals and metal compounds such as TiN, copper, chromium, iron, aluminum, lithium, GaN, GaAs, and Al ₂ O _3. Examples include quartz, quartz, and glass substrates. Among them, the substrate is preferably at least one selected from the group consisting of Si substrate, SiO ₂ substrate, SiON substrate and TiN substrate.
As the at least two kinds of metals contained on the surface of the substrate, for example, those conventionally known as the material of the wiring pattern can be used. Specific examples of the metal include copper, aluminum, nickel and gold.
In the present embodiment, as the substrate, one type may be used alone, or two or more types may be used in combination.

(Epoxy group-containing resin)
In the present embodiment, the “epoxy group-containing resin” is a relatively low molecular weight polymer (prepolymer) having two or more epoxy groups in one molecule, and a thermosetting resin produced by a ring-opening reaction of the epoxy group. Include.

As an epoxy resin (hereinafter referred to as “(G) component”), the adhesiveness between the resist pattern and the support is good, and the pattern collapse and the peeling of the resist pattern from the support are further suppressed. An epoxy resin having an epoxy group of is preferable, for example,
An epoxy group represented by the following general formula (g0-1) exists in the middle of the main chain of a polymer compound, and the carbon atom of the epoxy group forms a part of the main chain;
The epoxy group represented by the following general formula (g0-2) is contained in the side chain of the polymer compound, and the epoxy group represented by the following general formula (g0-2) is the main chain of the polymer compound. Forming the end;
The epoxy group represented by the following general formula (g0-3) is contained in the side chain of the polymer compound, and the epoxy group represented by the following general formula (g0-3) is the main chain of the polymer compound. Forming the end;
The epoxy group represented by the following general formula (g0-4) is contained in the side chain of the polymer compound, and the epoxy group represented by the following general formula (g0-4) is the main chain of the polymer compound. Forming the end;
The epoxy group represented by the following general formula (g0-5) is contained in the side chain of the polymer compound, and the epoxy group represented by the following general formula (g0-5) is the main chain of the polymer compound. Examples thereof include those forming a terminal.

［式中、Ｒ６３及びＲ６４はそれぞれ独立して水素原子又はアルキル基である。Ｒ６６〜Ｒ６８はそれぞれ独立して水素原子又はアルキル基である。Ｒ６６ａ、Ｒ６９ａ及びＲ６９ｂはそれぞれ独立して水素原子又はアルキル基であり、ｇ４は１〜２０の整数であり、ｇ５は１〜２０の整数である。］

[In the formula, R63 and R64 are each independently a hydrogen atom or an alkyl group. R66 to R68 are each independently a hydrogen atom or an alkyl group. R66a, R69a and R69b are each independently a hydrogen atom or an alkyl group, g4 is an integer of 1 to 20 and g5 is an integer of 1 to 20. ]

In the formula (g0-1), R63 and R64 are each independently a hydrogen atom or an alkyl group. The alkyl group for R63 and R64 is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. Among them, R63 and R64 are each preferably a hydrogen atom or a methyl group.
In the formula (g0-2), R66 to R68 are each independently a hydrogen atom or an alkyl group. The alkyl group in R66 to R68 is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. Among them, R66 is preferably a hydrogen atom or a methyl group; R67 to R68 are preferably a hydrogen atom or a methyl group, and particularly preferably all are hydrogen atoms.
In the formula (g0-3), R66a, R69a and R69b are each independently a hydrogen atom or an alkyl group. The alkyl group for R66a, R69a and R69b is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. Of these, R66a is preferably a hydrogen atom or a methyl group; R69a and R69b are each preferably a hydrogen atom or a methyl group, and particularly preferably both are hydrogen atoms.
g4 is an integer of 1 to 20, preferably 1 to 5, more preferably 1 or 2, and most preferably 2.
g5 is an integer of 1 to 20, preferably 1 to 5, more preferably 1 or 2, and most preferably 1.

Among the above, the epoxy group represented by the general formula (g0-1) is present in the middle of the main chain of the polymer compound, and the carbon atom of the epoxy group forms part of the main chain, The epoxy group represented by the general formula (g0-2) is contained in the side chain of the polymer compound, and the epoxy group represented by the general formula (g0-3) is contained in the side chain of the polymer compound. And the epoxy group represented by the general formula (g0-4) is contained in the side chain of the polymer compound.

More preferable examples of the component (G) include those having a repeating structure of the structural unit (g1) containing an epoxy group.
Those having this repeating structure are preferable because the adhesion between the resist pattern and the support is better when the mass average molecular weight is in the range of 1,000 to 50,000.

(Structural unit (g1))
The structural unit (g1) containing an epoxy group is not particularly limited, and examples thereof include a structural unit composed of an organic group containing an epoxy group, in which the carbon atom of the epoxy group forms part of the main chain.
As the other structural unit (g1), a structural unit derived from hydroxystyrene, a structural unit derived from acrylate ester, or a structural unit having a cyclic main chain (hereinafter referred to as "main chain cyclic structural unit"). .), and among these, a structural unit derived from an acrylate ester is preferable.

As the structural unit (g1), for example, structural units represented by the following general formulas (g1-1) to (g1-4) are disclosed in paragraphs [0012] to [0042] of JP-A-2003-076012. And a structural unit derived from the compound.
Among them, it is preferable that at least one selected from the group consisting of the structural units represented by the following general formulas (g1-1) to (g1-4) is included because the effect of the present invention is excellent.

［式中、Ｒ６１およびＲ６２はそれぞれ独立して置換基を有していてもよい二価の炭化水素基であり、Ｒ６３およびＲ６４はそれぞれ独立して水素原子又はアルキル基である。Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｒ６５は置換基を有していてもよい二価の炭化水素基であり、Ｒ６６〜Ｒ６８はそれぞれ独立して水素原子又はアルキル基である。Ｒ６５ａは置換基を有していてもよい二価の炭化水素基であり、Ｒ６６ａ、Ｒ６９ａ及びＲ６９ｂはそれぞれ独立して水素原子又はアルキル基であり、ｇ４は１〜２０の整数であり、ｇ５は１〜２０の整数である。Ｒ６５ｂは置換基を有していてもよい二価の炭化水素基である。］

[In the formula, R61 and R62 each independently represent a divalent hydrocarbon group which may have a substituent, and R63 and R64 each independently represent a hydrogen atom or an alkyl group. 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, R65 is a divalent hydrocarbon group which may have a substituent, and R66 to R68. Are each independently a hydrogen atom or an alkyl group. R65a is a divalent hydrocarbon group which may have a substituent, R66a, R69a and R69b are each independently a hydrogen atom or an alkyl group, g4 is an integer of 1 to 20, and g5 is It is an integer of 1 to 20. R65b is a divalent hydrocarbon group which may have a substituent. ]

In the formula (g1-1), R ⁶¹ and R ⁶² are each independently a divalent hydrocarbon group which may have a substituent.
The phrase "having a substituent" on the hydrocarbon group means that some or all of the hydrogen atoms in the hydrocarbon group are substituted with groups or atoms other than hydrogen atoms.

In R ⁶¹ or R ⁶² , the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
"Aliphatic hydrocarbon group" means a hydrocarbon group having no aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Specific examples of the aliphatic hydrocarbon group for R ⁶¹ or R ⁶² include a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group containing a ring in the structure thereof.
The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 8, more preferably 1 to 5, and most preferably 1 or 2.
As the linear aliphatic hydrocarbon group, preferably a linear alkylene group, and specific examples include a methylene group _[-CH 2 -], an ethylene group _{[- (CH 2) 2 -} ], trimethylene [ _{- (CH 2) 3 -]} , a tetramethylene group _{[- (CH 2) 4 -} ], a pentamethylene group _{[- (CH 2) 5 -} ] , and the like.
As the branched aliphatic hydrocarbon group, preferably a branched chain alkylene group, _{specifically, -CH (CH 3) -,} - CH (CH 2 CH 3) -, - C (CH 3) _{2 -, - C (CH 3} ) (CH 2 CH 3) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as - _{CH (CH 3) CH 2 -} , - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 Alkylethylene group such as CH ₃ ) ₂ —CH ₂ —; alkyltrimethylene group such as —CH(CH ₃ )CH ₂ CH ₂ —, —CH ₂ CH(CH ₃ )CH ₂ —, and —CH(CH ₃ ). Examples thereof include alkyl alkylene groups such as alkyl tetramethylene groups such as CH ₂ CH ₂ CH ₂ — and —CH ₂ CH(CH ₃ )CH ₂ CH ₂ —. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.
The linear or branched aliphatic hydrocarbon group (hereinafter referred to as "chain aliphatic hydrocarbon group") may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, an oxygen atom (═O) and the like.

Examples of the aliphatic hydrocarbon group containing a ring in its structure include a cyclic aliphatic hydrocarbon group (a group in which two or more hydrogen atoms have been removed from an aliphatic hydrocarbon ring), and the cyclic aliphatic hydrocarbon group described above. Examples of the group include a group bonded to the end of the chain-like aliphatic hydrocarbon group or interposed in the middle of the chain-like aliphatic hydrocarbon group.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic group is preferably a group in which two or more hydrogen atoms have been removed from a monocycloalkane having 3 to 6 carbon atoms, and examples of the monocycloalkane include cyclopentane and cyclohexane. The polycyclic group is preferably a group obtained by removing two or more hydrogen atoms from a polycycloalkane having 7 to 12 carbon atoms, and specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, Tetracyclododecane and the like can be mentioned.
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, an oxygen atom (=O), and the like.

Examples of the aromatic hydrocarbon group for R ⁶¹ or R ⁶² include monovalent aromatic groups such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. A divalent aromatic hydrocarbon group obtained by removing one more hydrogen atom from the aromatic hydrocarbon nucleus of the hydrocarbon group; some of the carbon atoms constituting the ring of the divalent aromatic hydrocarbon group are oxygen atoms. , An aromatic hydrocarbon group substituted with a hetero atom such as a sulfur atom or a nitrogen atom; a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group or the like. And the like, and an aromatic hydrocarbon group obtained by further removing one hydrogen atom from the nucleus of the aromatic hydrocarbon.
The aromatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (═O), and the like.

As R ⁶¹ or R ⁶² , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group is most preferable. preferable.

In the formula (g1-1), R ⁶³ and R ⁶⁴ are each independently a hydrogen atom or an alkyl group.
The alkyl group for R ⁶³ and R ⁶⁴ is the same as described in the above formula (g0-1).
Among them, each of R ⁶³ and R ⁶⁴ is preferably a hydrogen atom or a methyl group.

In the formula (g1-2), 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.
The alkyl group or halogenated alkyl group of R is the same as the alkyl group having 1 to 5 carbon atoms or the halogenated alkyl group having 1 to 5 carbon atoms which may be bonded to the α-position of the acrylic ester.
Among them, R is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and particularly preferably a hydrogen atom or a methyl group.

In the above formula (g1-2), R65 is a divalent hydrocarbon group which may have a substituent, and examples thereof include the same as R61 and R62 in the above formula (g1-1). A chain aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group is most preferable.
In the formula (g1-2), R66 to R68 are each independently a hydrogen atom or an alkyl group. The alkyl group in R66 to R68 is the same as described in the above formula (g0-2).
Among them, each of R66 to R68 is preferably a hydrogen atom or a methyl group.

In the formula (g1-3), R ^65a is a divalent hydrocarbon group which may have a substituent, and examples thereof include the same ones as R ⁶⁵ in the formula (g1-2). A chain aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group is most preferable.
In the formula (g1-3), R ^66a , R ^69a, and R ^69b are each independently a hydrogen atom or an alkyl group. The alkyl group in R ^66a , R ^69a and R ^69b is the same as described in the above formula (g0-3). Among them, each of R ^{66 to} R ⁶⁸ is preferably a hydrogen atom or a methyl group.
Both g4 and g5 are the same as described in the above formula (g0-3).

In the above formula (g1-4), R ^65b is a divalent hydrocarbon group which may have a substituent, and examples thereof include the same as R ⁶⁵ in the above formula (g1-2). A chain aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group is most preferable.

Specific examples of the structural units represented by the general formulas (g1-1) to (g1-4) are shown below.
In each formula below, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

In the component (G), one type of structural unit (g1) may be used alone, or two or more types may be used in combination.
Among the above, as the component (G), those having a structural unit represented by the above formula (g1-1) are preferable.
When the constitutional unit represented by the formula (g1-1) is used, the component (G) is a polymer (homopolymer) consisting of one kind of the constitutional unit represented by the formula (g1-1). Preferably.
When the constitutional unit represented by the formula (g1-2) or the formula (g1-3) is used, the component (G) includes the constitutional unit represented by the formula (g1-2) and other components described below. A copolymer having a structural unit;
A copolymer having a constitutional unit represented by the formula (g1-3) and other constitutional units described below;
A copolymer composed of repeating structural units represented by the formula (g1-2) and structural units represented by the formula (g1-3);
Copolymer having a constitutional unit represented by the formula (g1-2), a constitutional unit represented by the formula (g1-3), and other constitutional units described below.
Is preferred.

In the component (G), the proportion of the structural unit (g1) is preferably 10 mol% or more, more preferably 20 mol% or more, based on the total of all structural units constituting the component (G). , 30 mol% or more, more preferably 35 mol% or more, particularly preferably 100 mol%.
When the ratio of the structural unit (g1) is at least the lower limit value, the crosslinking efficiency with the support is increased, and the adhesiveness between the resist pattern and the support is further increased.

When the component (G) is a copolymer, the proportion of the structural unit (g1) is preferably 10 to 80 mol% based on the total of all structural units constituting the component (G), It is more preferably from 20 to 80 mol%, further preferably from 30 to 80 mol%.
When the ratio of the structural unit (g1) is at least the lower limit value, the crosslinking efficiency with the support is increased, and the adhesiveness between the resist pattern and the support is further increased. On the other hand, when it is at most the upper limit, the lithography properties such as resolution of the resist pattern and pattern collapse are improved when the surface modified layer is formed.

(Other structural units (g2))
The component (G) may have other structural unit (g2) other than the above structural unit (g1), if necessary, within a range that does not impair the effects of the present invention.
The other structural unit (g2) is not particularly limited, and a structural unit derived from a compound copolymerizable with the compound that induces the structural unit (g1) is preferable.
Specific examples of the other structural unit (g2) include structural units derived from acrylic acid and structural units derived from methacrylic acid (hereinafter, these are collectively referred to as "structural unit (g21)"); acrylic. A structural unit derived from an alkyl acrylate such as methyl acrylate or ethyl acrylate (preferably having 1 to 5 carbon atoms in the alkyl) (hereinafter referred to as "structural unit (g22)"); methyl methacrylate or A constitutional unit derived from an alkyl methacrylate such as ethyl methacrylate (preferably, the alkyl has 1 to 5 carbon atoms) (hereinafter referred to as "constitutional unit (g23)"); described later (A1-1). The structural units (a1) to (a4) and the like in the description of the components are preferred. Among the structural units (a1) to (a4), the structural units (a1), (a2), and (a4) are more preferable, because pattern collapse and peeling of the resist pattern from the support are further suppressed. The unit (a4) is more preferable.

In the component (G), one type of structural unit (g2) may be used alone, or two or more types may be used in combination.
In the component (G), the proportion of the structural unit (g2) is preferably 1 to 30 mol% and more preferably 5 to 25 mol% with respect to the total of all the structural units constituting the component (G). More preferably, it is more preferably 10 to 20 mol %.
When the ratio of the structural unit (g2) is at least the lower limit value, the lithography properties such as resolution of the resist pattern and pattern collapse are improved when the surface modified layer is formed. On the other hand, when it is at most the upper limit value, pattern collapse is further suppressed in the formation of the resist pattern. Further, it can be balanced with the structural unit (g1).

In the surface-modifying material according to the present embodiment, as the component (G), one type may be used alone, or two or more types may be used in combination.

In the present invention, the component (G) is preferably, for example, a polymer (homopolymer) formed by repeating the structural unit (g1) or a copolymer (copolymer) having the structural unit (g1) and the structural unit (g2). It can be mentioned as an example.
Specific preferred examples of such a copolymer include a copolymer having a structural unit (g1) and a structural unit (g21).
As the component (G), an epoxy resin having the following structural units is particularly preferable.

［式中、ｇ６およびｇ７はそれぞれ独立して１〜５の整数である。］

[In the formula, g6 and g7 are each independently an integer of 1 to 5. ]

The epoxy resin represented by the formula (G-1) is a homopolymer composed of repeating constitutional units represented by the formula (G-1).
In the above formula, g6 and g7 are each independently preferably 1 or 2, more preferably 1, and particularly preferably both g6 and g7 are 1.

［式中、Ｒは上記と同じであり、複数のＲはそれぞれ同じであっても異なっていてもよい。ｇ８は１〜５の整数であり、Ｒ^１はアルキル基である。］

[In the formula, R is the same as above, and a plurality of Rs may be the same or different. g8 is an integer of 1 to 5 and R ¹ is an alkyl group. ]

In the above formula, R is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and particularly preferably a hydrogen atom or a methyl group.
g8 is preferably 1 or 2, and more preferably 1.
R ¹ is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

［式中、Ｒは上記と同じであり、複数のＲはそれぞれ同じであっても異なっていてもよい。ｇ８は上記と同じである。ｇ９は１〜５の整数であり、ｇ４及びｇ５はそれぞれ上記と同じである。］

[In the formula, R is the same as above, and a plurality of Rs may be the same or different. g8 is the same as above. g9 is an integer of 1 to 5, and g4 and g5 are the same as above. ]

In the above formula, R is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and particularly preferably a hydrogen atom or a methyl group.
g8 is preferably 1 or 2, and more preferably 1.
g9 is preferably 1 or 2, and more preferably 1.
g4 is preferably 1 or 2, and more preferably 2.
g5 is preferably 1 or 2, and more preferably 1.

The polymer (homopolymer) or copolymer (copolymer) having a repeating structure of the structural unit (g1) is a monomer that induces a desired structural unit, for example, azobisisobutyronitrile (AIBN) or azobisisobutyric acid. It can be obtained by polymerizing by known radical polymerization using a radical polymerization initiator such as dimethyl.

The mass average molecular weight of the epoxy resin (hereinafter referred to as “(G) component”) in the present embodiment is preferably 2,000 to 30,000, more preferably 5,000 to 28,000, and more preferably 10,000 to 25,000. It is preferably 15000 to 22000, and most preferably.
When the mass average molecular weight of the component (G) is within the above range, a surface-modified layer can be formed that is well bonded to the support, and the adhesiveness between the resist pattern and the support is excellent.
When the mass average molecular weight is equal to or more than the lower limit value, the efficiency of crosslinking with the support is increased, and the support and the surface modified layer are firmly attached to each other. Further, when a solution obtained by dissolving the component (G) in an organic solvent is used as the surface modifying material, the solution has an appropriate viscosity, and it becomes easy to uniformly apply the solution onto the support. On the other hand, when it is at most the upper limit value, increase in viscosity of the solution is suppressed, and it becomes easy to uniformly coat the solution on the support.
In the present invention, the "mass average molecular weight" refers to a value based on polystyrene conversion by gel permeation chromatography. Hereinafter, the mass average molecular weight may be represented as Mw.

The dispersity (Mw/Mn) of the component (G) is preferably 1.0 to 5.0, more preferably 2.0 to 4.8, most preferably 3.0 to 4.5. In addition, "Mn" shows a number average molecular weight.

In the surface modification material in the present embodiment, the content of the component (G) is preferably 0.010 to 0.300 mass%, more preferably 0.010 to 0.250 mass%, It is more preferably 0.015 to 0.200 mass %.
When the content of the component (G) is at least the lower limit value, the adhesion between the resist pattern and the support will be higher. Further, when a solution obtained by dissolving the component (G) in an organic solvent is used as the surface modifying material, the solution has an appropriate viscosity, and it becomes easy to uniformly apply the solution onto the support. On the other hand, when it is at most the upper limit value, the increase in viscosity of the solution is suppressed, and the solution is easily uniformly coated on the support.

(Other ingredients)
The surface modification material in the present embodiment may contain other components other than the component (G).
Examples of the other components include organic solvents, sulfur-containing organic compounds, nitrogen-containing organic compounds, surfactants, organic acids, photoacid generators, photobase generators, dyes and the like.

Any organic solvent may be used as long as it can dissolve the component (G) into a uniform solution, and examples thereof include those used as organic solvents for general chemical amplification resist compositions. ..
Examples of the organic solvent include lactones such as γ-butyrolactone; ketones such as acetone, methylethylketone, cyclohexanone, methyl-n-pentylketone, methylisopentylketone and 2-heptanone; ethylene glycol, diethylene glycol, propylene glycol and diketone. A polyhydric alcohol such as propylene glycol; a compound having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, a polyhydric alcohol or a compound having an ester bond Derivatives of polyhydric alcohols such as compounds having an ether bond such as monoalkyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether and monobutyl ether or monophenyl ethers [among these, propylene glycol monomethyl ether acetate (PGMEA ), propylene glycol monomethyl ether (PGME)]]; cyclic ethers such as dioxane, methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methoxy. Esters such as methyl propionate and ethyl ethoxypropionate; anisole, ethylbenzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, Examples thereof include aromatic organic solvents such as cymene and mesitylene.
The organic solvent may be used singly or as a mixed solvent of two or more kinds.

The form of the surface modifying material in the present embodiment is not particularly limited as long as it contains the component (G) and can form the surface modifying layer. For example, the component (G) is dissolved in an organic solvent. It may be used as a solution formed from the above, or may be used as a sheet-like product obtained by drying the solution.

(Baking process)
In the baking step, the substrate coated with the epoxy group-containing resin (surface modification material) is baked to form a film (surface modification layer).

The baking temperature in the baking step is preferably 80 to 400° C., more preferably 180 to 300° C., the baking time is preferably 15 to 120 seconds, and more preferably 30 to 90 seconds. preferable.
When the epoxy resin used for the surface-modifying material has a structural unit represented by the general formula (g1-1), the bake temperature is preferably 160 to 260°C, and 180 to 250°C. It is more preferable that the temperature is 200 to 240°C.
The epoxy resin used for the surface-modifying material is represented by the structural unit represented by the general formula (g1-2), the structural unit represented by the general formula (g1-3), or the general formula (g1-4). When it has a constitutional unit, the baking temperature is preferably 85 to 350°C, and more preferably 120 to 300°C.
When any of the above baking temperatures is at least the lower limit value, the adhesiveness between the resist pattern and the support is enhanced. On the other hand, when it is at most the upper limit value, the effect of improving the adhesiveness is sufficiently obtained.

The thickness of the surface modified layer is preferably 0.01 to 3.5 nm, more preferably 0.3 to 2.5 nm. When the thickness is not less than the lower limit, there are effects such that the adhesiveness between the resist pattern and the support is enhanced, and resistance to etching is obtained. When the thickness is not more than the upper limit value, the effect of providing the surface modification layer can be sufficiently obtained.

In the present embodiment, the arithmetic mean roughness Ra of the substrate after the baking step (arithmetic mean roughness Ra of the surface modified layer) is preferably 1.0 nm or less, and more preferably 0.9 nm or less. , 0.85 nm or less is more preferable.
The arithmetic mean roughness Ra in the present embodiment means a so-called arithmetic mean roughness defined by JIS B0601:2001.
When the arithmetic mean roughness Ra of the substrate after the baking step is equal to or less than the upper limit value of the above preferable range, the lithography characteristics of the resist pattern formed on the substrate are improved.

In the present embodiment, the contact angle of the substrate after the baking step (contact angle of the surface modification layer) is preferably 70° or less, more preferably 65° or less, and 60° or less. More preferable.
When the contact angle of the substrate after the baking step is not more than the upper limit value of the above-mentioned preferable range, the adhesion between the resist pattern formed on the substrate and the substrate is improved.
The contact angle of the substrate after the baking process (contact angle of the surface modification layer) is DROP MASTER after dropping a predetermined amount of water on the surface of the substrate after the baking process (the surface on which the surface modification layer is formed). -700 (product name, manufactured by Kyowa Interface Science Co., Ltd.), AUTO SLIDING ANGLE: SA-30DM (product name, manufactured by Kyowa Interface Science Co., Ltd.), AUTO DISPENSER: AD-31 (product name, manufactured by Kyowa Interface Science Co., Ltd.), etc. It can be measured using the measuring device.

<Method of forming resist pattern>
In the present embodiment, the resist pattern can be formed on the substrate (the substrate on which the surface modification layer has been formed) after the baking process.
The method for forming the resist pattern is not particularly limited, but, for example, a step of forming a resist film using a resist composition on the substrate after the baking step (hereinafter referred to as “resist film forming step”) and exposing the resist film. A method including a step (hereinafter referred to as “exposure step”) and a step of forming a resist pattern by alkali developing the resist film (hereinafter referred to as “developing step”) can be mentioned.

[Resist film formation process]
The method for forming a resist film using a resist composition on the support on which the surface modified layer is formed is not particularly limited, and a conventionally known method can be used.
Specifically, the resist composition is applied onto a support having a surface-modified layer formed thereon by a conventionally known method using, for example, a spinner, and preferably baked under a temperature condition of 80 to 150° C. ( Prebaking is preferably performed for 40 to 120 seconds, more preferably 60 to 90 seconds to volatilize the organic solvent and form a resist film.
The thickness of the resist film is preferably 50 to 500 nm, more preferably 50 to 450 nm. Within this range, the resist pattern can be formed with high resolution, and sufficient resistance to etching can be obtained.
In the resist pattern forming method according to the present embodiment, it is preferable that the resist composition is a chemically amplified resist composition because of fine resolution processing. Details of the resist composition will be described later.

[Exposure process]
Next, the resist film formed on the support on which the surface modification layer is formed is exposed.
Specifically, for example, the resist film formed as described above is selectively exposed through a photomask, and preferably post exposure bake (PEB) treatment is performed.

The wavelength used for exposure is not particularly limited, and may be KrF excimer laser, ArF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. It can be done using radiation.

The selective exposure of the resist film may be either normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or immersion exposure.
In the immersion exposure, the portion between the lens and the resist film on the wafer, which is conventionally filled with an inert gas such as air or nitrogen, is exposed to a solvent (refractive index higher than that of air) at the time of exposure. Exposure is performed in a state of being filled with a liquid immersion medium).
More specifically, the immersion exposure is performed by a solvent (immersion medium) having a refractive index larger than that of air between the resist film obtained as described above and the lens at the lowest position of the exposure apparatus. Can be carried out by exposing (immersion exposure) through a desired photomask in that state.
As the liquid immersion medium, a solvent having a refractive index higher than that of air and lower than that of the resist film exposed by the immersion exposure is preferable. The refractive index of such a solvent is not particularly limited as long as it falls within the above range.
Examples of the solvent having a refractive index higher than that of air and smaller than that of the resist film include water, fluorine-based inert liquid, silicon-based solvent, hydrocarbon-based solvent, and the like.
As the liquid immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility and the like.

The PEB process is performed at a baking temperature that changes (increases or decreases) the solubility of the resist film in an alkali developing solution.
That is, the resist film, for example, a resist film made of a chemically amplified resist composition, is subjected to PEB treatment after exposure, whereby the acid generated from the acid generator component diffuses in the resist film and the acid The change (increase/decrease) in the solubility of the resist film in the alkali developing solution due to the action proceeds.
Specifically, for example, after selectively exposing the resist film through a photomask on which a predetermined pattern is formed, PEB (post-exposure heating), preferably 40, is performed under a temperature condition of preferably 80 to 150°C. ~120 seconds, more preferably 60-90 seconds.

[Development process]
Next, after the exposure, preferably the post-exposure bake (PEB) treatment of the resist film is alkali-developed to form a resist pattern.
The alkali development can be carried out by a known method using an alkaline aqueous solution, for example, a tetramethylammonium hydroxide (TMAH) aqueous solution having a concentration of 0.1 to 10% by mass.
After the above alkali development, a rinse treatment with water or the like may be performed.
Further, after the above alkali development, bake treatment (post bake) may be further performed. Post-baking is usually performed under conditions of about 100° C. (since it is performed for the purpose of removing water after alkali development or rinsing), and the treatment time is preferably 30 to 90 seconds.

In the resist pattern forming method of the present embodiment, by performing the above-mentioned surface modification layer forming step, resist film forming step, exposing step and developing step, in addition to the effects of the present invention, a resist pattern faithful to the mask pattern is obtained. Can be formed.

≪Pattern formation method≫
The pattern forming method in the present embodiment includes a step of performing an etching process on the support on which the resist pattern is formed by the resist pattern forming method in the present embodiment.
A known method can be used as the etching method.
For example, in the wet etching process, hydrofluoric acid (HF), ammonium fluoride (NH ₄ F), or an aqueous solution in which these are mixed is used as an etching solution to remove a support having a resist pattern formed therein. Immersion or the like is performed, and preferably, the treatment temperature is 23 to 60° C. and the treatment time is 15 to 3600 seconds.
As the dry etching treatment, oxygen plasma etching and etching using a halogen gas (preferably a fluorocarbon-based gas such as CF ₄ gas or CHF ₃ gas) can be cited as suitable methods.
By thus performing the etching process on the support, a semiconductor device or the like can be manufactured.
In the pattern forming method of the present embodiment, when the support on which the resist pattern is formed is subjected to the etching treatment, the edges of the resist pattern are not easily peeled off from the support, and a pattern with high resolution can be formed.

According to the method for controlling the surface physical properties of the substrate according to the present embodiment described above, the effect that desired surface physical properties can be obtained without depending on the type of substrate is obtained. Further, according to the resist pattern forming method of the present embodiment, it is possible to obtain an effect that a resist pattern having excellent adhesion to a substrate and excellent lithographic properties can be formed. Further, according to the pattern forming method of the present embodiment, it is possible to obtain the effect that the resist pattern is hardly peeled off from the support when the etching process is performed.
The reason why these effects are obtained is not clear, but it is presumed as follows.
For example, when the substrate is treated with hexamethyldisilazane (HMDS), the hydrophilic group on the substrate surface is physically pressed to improve the contact angle and the adhesion with the resist pattern. On the other hand, in the present embodiment, since the epoxy group-containing resin is used, the hydrophilic group on the substrate surface reacts with the epoxy group in the epoxy group-containing resin by the baking step, and the epoxy group-containing resin is self-crosslinked. It is heat-cured and a surface modification layer is formed on the surface of the substrate. Therefore, in the present embodiment, the film thickness of the substrate surface (surface modification layer) is thin and in-plane uniformity and surface roughness of the substrate surface are improved as compared with the case where the substrate is subjected to HMDS treatment. Presumed to be.
Further, in the surface modified layer, the epoxy groups that have not reacted in the above crosslinking reaction remain. Therefore, when forming a resist pattern on the surface modification layer, it is presumed that the residual epoxy groups react with the hydrophilic groups in the resist film to improve the adhesion between the surface modification layer and the resist pattern.
Further, according to the method of controlling the surface physical properties of the substrate according to the present embodiment, even when two or more types of substrates are used in combination, the surface physical properties can be controlled to be equivalent.

Further, in the method of forming the resist pattern according to the present embodiment, the adhesiveness between the resist pattern and the support is excellent, and the resist pattern is less likely to peel off from the support even after the etching treatment. The reason why the above effect is obtained is not clear, but it is presumed as follows.
It is known from equations (Dupre's equation, Young's equation, Young-Dupre's equation) showing the relationship between the contact angle and the adhesiveness that the smaller the value of the contact angle, the higher the adhesive force.
According to the studies by the present inventors, it has been confirmed that the value of the contact angle on the surface of the surface modified layer formed on the support becomes smaller as the baking temperature becomes higher. This indicates from the equation showing the above relationship that the support is more strongly bonded to the surface modification layer as the baking is performed at a higher temperature. Thus, it is considered that the resist pattern formed through the surface modification layer firmly bonded to the support has excellent adhesion to the support, and the above-mentioned effects can be obtained.

For details of resist composition:
The resist composition used in the resist pattern forming method according to the present embodiment is not particularly limited, and conventionally known ones can be used.
As described above, such a resist composition is preferably a chemically amplified resist composition, and specifically, specifically, the base component (A) (hereinafter, referred to as “(( A component containing (A) component") and an organic solvent component (S) (hereinafter referred to as "(S) component") and having an acid generating ability is preferable.

Examples of such a resist composition include those having an acid generating ability to generate an acid upon exposure, and the component (A) may generate an acid upon exposure, and the addition is made separately from the component (A). The agent component may generate an acid upon exposure.
Such a resist composition, specifically,
(1) It may contain an acid generator component (B) that generates an acid upon exposure (hereinafter referred to as “(B) component”),
(2) The component (A) may be a component that generates an acid upon exposure,
(3) The component (A) may be a component which generates an acid upon exposure, and may further contain the component (B).
That is, in the cases of the above (2) and (3), the component (A) becomes “a base material component which generates an acid upon exposure and whose solubility in a developing solution is changed by the action of the acid”. When the component (A) is a base material component that generates an acid upon exposure to light and the solubility of the component in a developing solution changes by the action of the acid, the component (A1) described below generates an acid upon exposure to light, and A polymer compound whose solubility in a developing solution is changed by the action of an acid is preferable. As such a polymer compound, a resin having a structural unit that generates an acid upon exposure can be used. As the structural unit that generates an acid upon exposure, a known unit can be used. Among them, the resist composition of the present invention is preferably the case of the above (1).

-About component (A) In the present invention, the "base material component" is an organic compound having a film-forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film forming ability is improved and, in addition, a nano-level resist pattern is easily formed.
The organic compound used as the base material component is roughly classified into a non-polymer and a polymer.
As the non-polymer, one having a molecular weight of 500 or more and less than 4000 is usually used. Hereinafter, the term "low molecular weight compound" means a non-polymer having a molecular weight of 500 or more and less than 4000.
As the polymer, one having a molecular weight of 1,000 or more is usually used. Hereinafter, the term "resin" or "polymer compound" refers to a polymer having a molecular weight of 1000 or more.
As the molecular weight of the polymer, a polystyrene-equivalent mass average molecular weight by GPC (gel permeation chromatography) is used.

When the resist composition is a “negative resist composition for an alkali developing process” which forms a negative resist pattern in an alkali developing process, or a “positive resist for solvent developing process” which forms a positive resist pattern in a solvent developing process. In the case of “type resist composition”, as the component (A), a base component (A-2) (hereinafter referred to as “(A-2) component”) which is soluble in an alkali developing solution is preferably used, Further, a crosslinking agent component is blended. In such a resist composition, for example, when an acid is generated from the component (B) upon exposure, the acid acts to cause crosslinking between the component (A-2) and the crosslinking agent component, resulting in alkali development. Solubility in liquid decreases (solubility in organic developer increases). Therefore, in the formation of the resist pattern, when the resist film obtained by applying the resist composition on a support is selectively exposed, the exposed portion is hardly soluble in an alkali developing solution (in an organic developing solution). On the other hand, the unexposed area remains soluble in the alkali developing solution (hardly soluble in the organic developing solution) while it does not change. Therefore, the negative resist pattern is formed by developing with the alkali developing solution. It Further, at this time, a positive resist pattern is formed by developing with an organic developer.
As a preferable component (A-2), a resin soluble in an alkali developing solution (hereinafter referred to as "alkali-soluble resin") is used.
As the cross-linking agent component, for example, an amino-based cross-linking agent such as glycoluril having a methylol group or an alkoxymethyl group, a melamine-based cross-linking agent, or the like is usually used because a good resist pattern with less swelling can be formed, which is preferable. The compounding amount of the crosslinking agent component is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the alkali-soluble resin.

When the resist composition is a “positive resist composition for alkali development process” which forms a positive resist pattern in an alkali development process, or a “negative solvent development process which forms a negative resist pattern in a solvent development process”. In the case of "type resist composition", as the component (A), a base component (A-1) whose polarity increases by the action of an acid (hereinafter referred to as "component (A-1)") is preferably used. To be By using the component (A-1), the polarity of the base material component changes before and after exposure, so that good development contrast can be obtained not only in the alkali development process but also in the solvent development process.
When an alkali development process is applied, the component (A-1) is poorly soluble in an alkali developing solution before exposure, and, for example, when an acid is generated from the component (B) due to exposure, the action of the acid causes The polarity is increased and the solubility in an alkaline developer is increased. Therefore, in the formation of a resist pattern, when the resist film obtained by applying the resist composition onto a support is selectively exposed, the exposed portion changes from poorly soluble to soluble in an alkali developing solution. Since the unexposed portion remains sparingly soluble in alkali, it is subjected to alkali development to form a positive resist pattern.
On the other hand, when a solvent development process is applied, the component (A-1) has a high solubility in an organic developing solution before exposure, and when an acid is generated by exposure, it has a high polarity due to the action of the acid. Solubility in organic developers decreases. Therefore, in the formation of a resist pattern, when the resist film obtained by applying the resist composition onto a support is selectively exposed, the exposed portion changes from soluble to slightly soluble in an organic developer. On the other hand, since the unexposed portion remains soluble and does not change, by developing with an organic developing solution, contrast can be provided between the exposed portion and the unexposed portion, and a negative resist pattern is formed.

As the component (A) used in the resist composition in the present embodiment, a structural unit (a1) containing an acid-decomposable group whose polarity increases by the action of an acid, a structural unit (a2) containing a lactone-containing cyclic group, structural unit containing a polar group-containing aliphatic hydrocarbon group (a3), a structural unit containing a non-acid-dissociable cyclic group (a4), carbonate-containing cyclic group, or -SO 2 _- structural unit containing an containing cyclic group A resin component having (a5) or the like is preferable.

..Structural units (a1)
The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity increases due to the action of an acid.
The "acid-decomposable group" is an acid-decomposable group capable of cleaving at least a part of the bonds in the structure of the acid-decomposable group by the action of an acid.
Examples of the acid-decomposable group whose polarity increases by the action of an acid include groups that decompose to form a polar group by the action of an acid.
Examples of the polar group, such as carboxy group, a hydroxyl group, an amino group, such as a sulfo group _(-SO 3 H) and the like. Among these, a polar group containing -OH in the structure (hereinafter sometimes referred to as "OH-containing polar group") is preferable, a carboxy group or a hydroxyl group is preferable, and a carboxy group is particularly preferable.
More specific examples of the acid-decomposable group include a group in which the polar group is protected with an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected with an acid-dissociable group).
Here, the “acid dissociable group” means
(I) an acid dissociable group capable of cleaving the bond between the acid dissociable group and an atom adjacent to the acid dissociable group by the action of an acid, or
(Ii) A group capable of cleaving a bond between the acid-dissociable group and an atom adjacent to the acid-dissociable group by further decarboxylation reaction after a part of the bond is cleaved by the action of an acid. ,
To both sides.
The acid dissociable group constituting the acid decomposable group needs to be a group having a lower polarity than the polar group generated by the dissociation of the acid dissociable group, whereby the acid dissociable group is acted upon by the action of an acid. When is dissociated, a polar group having a higher polarity than the acid dissociable group is generated and the polarity is increased. As a result, the polarity of the entire component (A) increases. Due to the increase in polarity, the solubility in the developing solution relatively changes, the solubility in the developing solution increases in the case of an alkaline developing solution, and the solubility in the developing solution in the case of an organic developing solution increases. Decrease.

The acid dissociable group is not particularly limited, and those proposed so far as the acid dissociable group of the base resin for the chemically amplified resist can be used.

The structural unit (a1) contained in the component (A) may be one type or two or more types.
The proportion of the structural unit (a1) in the component (A) is preferably 20 to 80 mol%, more preferably 20 to 75 mol%, and further preferably 25 to 25, relative to the total of all the structural units constituting the component (A). 70 mol% is more preferable.

..Structural units (a2)
The structural unit (a2) is a structural unit containing a lactone-containing cyclic group (provided that the structural unit (a1) described above is excluded).
The lactone-containing cyclic group of the structural unit (a2) is effective in increasing the adhesion of the resist film to the substrate when the component (A) is used for forming the resist film.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing —O—C(═O)— in its ring skeleton. The lactone ring is counted as the first ring, and a lactone ring alone is referred to as a monocyclic group, and a lactone ring having another ring structure is referred to as a polycyclic group regardless of the structure. The lactone-containing cyclic group may be either a monocyclic group or a polycyclic group.

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 from 1 to 80 mol%, more preferably from 5 to 70 mol%, based on the total of all structural units constituting the component (A), and from 10 to 10. 65 mol% is more preferable, and 10 to 60 mol% is particularly preferable.

..Structural units (a3)
The structural unit (a3) is a structural unit containing a polar group-containing aliphatic hydrocarbon group (provided that the structural units (a1) and (a2) described above are excluded).
When the component (A) has the structural unit (a3), the hydrophilicity of the component (A) is increased, which contributes to improvement in resolution.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group is replaced with a fluorine atom, and the like, and a hydroxyl group is particularly preferable.
Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group, and can be appropriately selected and used from, for example, a large number of proposals for resins for resist compositions for ArF excimer lasers. The cyclic group is preferably a polycyclic group, and more preferably has 7 to 30 carbon atoms.

The structural unit (a3) contained in the component (A) may be one type or two or more types.
The proportion of the structural unit (a3) in the component (A) is preferably from 5 to 50 mol%, more preferably from 5 to 40 mol%, based on the total of all structural units constituting the component (A), and from 5 to 5. 25 mol% is more preferable.

..Structural units (a4)
The structural unit (a4) is a structural unit containing an acid non-dissociable cyclic group.
When the component (A) has the structural unit (a4), the dry etching resistance of the resist pattern formed is improved.
The “acid non-dissociable cyclic group” in the structural unit (a4) is a ring that remains in the structural unit without being dissociated when the acid is generated from the component (B) upon exposure to the acid. It is a formula group.
The proportion of the structural unit (a4) in the component (A) is preferably 1 to 30 mol% and more preferably 10 to 20 mol% based on the total of all structural units constituting the component (A).

..Structural units (a5)
The structural unit (a5) is a structural unit containing a —SO ₂ — containing cyclic group or a carbonate containing cyclic group.

And _- "-SO 2 containing cyclic group", -SO 2 _- within the ring skeleton thereof shows a cyclic group containing a ring containing, in particular, -SO 2 _- sulfur atom (S) is in A cyclic group that forms part of the ring skeleton of the cyclic group. A ring containing —SO ₂ — in its ring skeleton is counted as the first ring, and if it is the only ring, it is a monocyclic group, and if it has another ring structure, it is a polycyclic group regardless of its structure. Called. The —SO ₂ — containing cyclic group may be monocyclic or polycyclic.
The —SO ₂ — containing cyclic group is particularly a cyclic group containing —O—SO ₂ — in its ring skeleton, that is, —O—S— in —O—SO ₂ — forms a part of the ring skeleton. It is preferably a cyclic group containing a sultone ring to be formed.

The “carbonate-containing cyclic group” refers to a cyclic group containing a ring (carbonate ring) containing —O—C(═O)—O— in its ring skeleton. The carbonate ring is counted as the first ring, and a carbonate ring alone is referred to as a monocyclic group, and a carbonate ring having another ring structure is referred to as a polycyclic group regardless of the structure. The carbonate-containing cyclic group may be either a monocyclic group or a polycyclic group.

The structural unit (a5) contained in the component (A) may be one type or two or more types.
The proportion of the structural unit (a5) in the component (A) is preferably from 1 to 80 mol%, more preferably from 5 to 70 mol%, and further preferably from 10 to 65, based on the total of all the structural units constituting the component (A). Mol% is more preferable, and 10-60 mol% is especially preferable.

In the resist composition of this embodiment, the component (A) preferably contains a polymer compound (A1) having a structural unit (ap) containing a polar group (hereinafter, also referred to as “component (A1)”). ..
The polar group in the structural unit (ap) includes a hydroxyl group, a cyano group, a carboxy group, a sulfo group, a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group is substituted with a fluorine atom, a carbonyl group (-C(=O)). -), carbonyloxy group (-C(=O)-O-), carbonate group (-O-C(=O)-O-), sulfonyl group (-S(=O) _2- ), sulfonyloxy group (-S(=O) _2- O-) and the like.

Examples of the preferred component (A1) include polymer compounds having the structural unit (a1). As the component (A1), specifically, a polymer compound having the structural unit (a1) and the structural unit (a2), a polymer compound having the structural unit (a1) and the structural unit (a3), a structural unit ( a1) and a structural unit (a5), a polymeric compound, a structural unit (a1), a structural unit (a2) and a structural unit (a3), a structural unit (a1) and a structural unit (a3) And a polymer compound having a structural unit (a5).

The mass average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of the component (A) is not particularly limited and is preferably 1000 to 50000, more preferably 1500 to 30000, and particularly 2000 to 20000. preferable.

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

-About (S) component The resist composition in the present embodiment can be prepared by dissolving the resist material in an organic solvent component ((S) component).
As the component (S), any component capable of dissolving each component to be used and forming a uniform solution may be used, and any one of those conventionally known as a solvent for a chemically amplified resist composition may be appropriately used. It can be selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, and the like. Polyhydric alcohols; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, monomethyl ethers of the polyhydric alcohols or compounds having an ester bond, monoethyl Derivatives of polyhydric alcohols such as monoalkyl ethers such as ether, monopropyl ether, monobutyl ether or compounds having an ether bond such as monophenyl ether [among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl Ether (PGME) is preferred]; cyclic ethers such as dioxane, methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethoxy. Esters such as ethyl propionate; anisole, ethylbenzyl ether, cresylmethyl ether, diphenyl ether, dibenzyl ether, phenetol, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc. Examples thereof include aromatic organic solvents and dimethyl sulfoxide (DMSO).
As the component (S), one type may be used alone, or two or more types may be used as a mixed solvent.
For example, a mixed solvent obtained by mixing PGMEA and a polar solvent is preferable.
The amount of the component (S) used is not particularly limited, and is appropriately set according to the coating film thickness at a concentration that can be applied to a substrate or the like. Generally, the component (S) is used so that the solid content concentration of the resist composition is preferably in the range of 1 to 20% by mass, more preferably 2 to 15% by mass.

-Regarding Optional Components In addition to the components (A) and (S), the resist composition according to the present embodiment includes an acid generator component (B) (component (B)) that generates an acid upon exposure and an acid diffusion control agent ( Hereinafter, "(D) component"), at least one compound (E) (hereinafter referred to as "(E) component") selected from the group consisting of organic carboxylic acids, phosphorus oxo acids and derivatives thereof, fluorine. You may contain an additive (henceforth "(F) component") etc.

Component (B) The component (B) is an acid generator component that generates an acid upon exposure.
The component (B) is not particularly limited, and those which have been proposed as acid generators for chemically amplified resists can be used.
Examples of the component (B) include onium salt-based acid generators such as iodonium salts and sulfonium salts, oxime sulfonate-based acid generators, diazomethane-based acid generators such as bisalkyl or bisarylsulfonyldiazomethanes and poly(bissulfonyl)diazomethanes. Examples thereof include acid generators, nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators. Above all, it is preferable to use an onium salt-based acid generator.

In the resist composition of this embodiment, as the component (B), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (B), the content of the component (B) is preferably 0.5 to 60 parts by mass, more preferably 1 to 50 parts by mass, relative to 100 parts by mass of the component (A). , 1 to 40 parts by mass is more preferable. By setting the content of the component (B) within the above range, pattern formation is sufficiently performed. Further, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is easily obtained, and the storage stability becomes better.

Component (D) Component (D) is an acid diffusion control agent component.
The component (D) acts as a quencher that traps the acid generated by exposure from the component (B) and the like.
The component (D) may be a photodegradable base (D1) (hereinafter referred to as “(D1) component”) that decomposes upon exposure and loses acid diffusion controllability, or a nitrogen-containing organic that does not correspond to the component (D1). The compound (D2) (hereinafter referred to as “component (D2)”) may also be used.

The content of the component (D1) is preferably 0.5 to 10.0 parts by mass, more preferably 0.5 to 8.0 parts by mass, and still more preferably 1.0 to 8. 0 mass part is more preferable. When it is at least the preferred lower limit of the above range, particularly good lithographic properties or resist pattern shapes are likely to be obtained. When it is at most the upper limit of the above range, the sensitivity can be favorably maintained and the throughput is also excellent.

As the component (D2), an aliphatic amine, particularly a secondary aliphatic amine or a tertiary aliphatic amine is preferable. The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.
Examples of the aliphatic amine include amines (alkylamines or alkylalcohol amines) or cyclic amines in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or a hydroxyalkyl group having 12 or less carbon atoms.
The content of the component (D2) is usually 0.01 to 5.0 parts by mass with respect to 100 parts by mass of the component (A). By setting the amount within the above range, the resist pattern shape, the stability over time of leaving and the like are improved.

In the resist composition of this embodiment, as the component (D), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (D), the content of the component (D) is preferably 0.1 to 15 parts by mass, and 0.3 to 12 parts by mass with respect to 100 parts by mass of the component (A). More preferably, 0.5 to 12 parts by mass is even more preferable. When it is at least the preferred lower limit of the above range, the lithographic properties such as LWR are further improved when the composition is used as a resist composition. Further, a better resist pattern shape can be obtained. When it is at most the upper limit of the above range, the sensitivity can be favorably maintained and the throughput is also excellent.

Component (E) The component (E) is at least one compound selected from the group consisting of organic carboxylic acids and phosphorus oxoacids and their derivatives. By containing the component (E), it is possible to prevent the sensitivity from deteriorating and to improve the resist pattern shape, the stability with leaving and the like.
In the resist composition according to the present embodiment, as the component (E), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (E), the content of the component (E) is usually 0.01 to 5.0 parts by mass with respect to 100 parts by mass of the component (A).

-About (F) component (F) component is a fluorine additive. By containing the component (F), water repellency is imparted to the resist film.
Examples of the component (F) are described in JP 2010-002870 A, JP 2010-032994 A, JP 2010-277043 A, JP 2011-13569 A and JP 2011-128226 A. And the fluorine-containing polymer compound.
In the resist composition of this embodiment, as the component (F), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (F), the content of the component (F) is used in the range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the component (A).

The resist composition may further contain a miscible additive such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, and a dye, if desired. It can be added and contained as appropriate.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

<Preparation of epoxy polymer solution>
Epoxy polymer represented by the following chemical formula (G-1-1) (mass average molecular weight (Mw): 20000, dispersity (Mw/Mn): 4.0), PGMEA/γ-butyrolactone = 90/10 (mass An epoxy polymer solution (epoxy polymer concentration 0.02% by mass) was prepared in a mixed solvent of (ratio).

<Evaluation of board dependence>
(Test Examples 1 to 4)
The epoxy polymer solution was applied onto the substrate shown in Table 1, baked at 240° C. for 60 seconds, and dried to form an organic film.
2 μL of water was dropped on the surface of the obtained organic film, and the static contact angle was measured using DROP MASTER-700 (product name, manufactured by Kyowa Interface Science Co., Ltd.). This measured value is shown in Table 1 as "contact angle (°)".
(Comparative Test Examples 1 to 4)
Hexamethylsilazane (HMDS) treatment was performed on the substrates shown in Table 1 at 180° C. for 75 seconds, and contact angles (°) of the formed films were measured in the same manner as in Test Examples 1 to 4. The results are shown in Table 1.

From the results shown in Table 1, it was confirmed that in Test Examples 1 to 4, the contact angle could be controlled to be equal to or higher than that in Comparative Test Examples 1 to 4 using the same substrate. In addition, in Test Examples 1 to 4, since the contact angle was controlled to the same value, it was confirmed that the contact angle can be controlled regardless of the type of the substrate.

Claims (5)

Application of applying an epoxy group-containing resin to the surface of two or more kinds of substrates selected from the group consisting of Si substrate, SiO ₂ substrate, SiON substrate and TiN substrate, the surface of which contains at least two types of metals Process,
A baking step of baking the substrate,
Only including,
A method of controlling surface physical properties of a substrate , wherein a contact angle of the substrate after the baking step is 60° or less . The method for controlling the surface physical properties of the substrate according to claim 1, wherein the epoxy group-containing resin has a structural unit represented by the following general formula (g1-1).

[In the formula, R ⁶¹ and R ⁶² are each independently a divalent hydrocarbon group which may have a substituent, and R ⁶³ and R ⁶⁴ are each independently a hydrogen atom or an alkyl group. ] The method for controlling the surface physical properties of the substrate according to claim 1, wherein the substrate is heated at 160 to 260° C. in the baking step. The method for controlling the surface physical properties of the substrate according to claim 1, wherein the arithmetic mean roughness Ra of the substrate after the baking step is 1.0 nm or less. METHOD weight average molecular weight of the epoxy group-containing resin is 10,000 to 30,000, the dispersion degree of 3.0 to 5.0, to control the surface properties of the substrate according to any one of claims 1-4 ..