KR20120045028A - Resist underlayer film-forming composition which contains polymer photoacid generator, and method for forming resist pattern using same - Google Patents

Abstract

｛식(A-1) 및 식(A-2) 중, R₁, R₂, R₃, R₄, R₅ 및 R₆은 유기기를 나타낸다.}[PROBLEMS] To provide a resist underlayer film forming composition containing a polymer type photoacid generator and a method of forming a resist pattern using the same.
[Resolution] The resist underlayer film forming composition containing the polymer which has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2).

In formula (A-1) and formula (A-2), R <_1> , R <_2> , R <_3> , R <_4> , R <_5> and R <_6> represent an organic group.}

Description

RESIST UNDERLAYER FILM-FORMING COMPOSITION WHICH CONTAINS POLYMER PHOTOACID GENERATOR, AND METHOD FOR FORMING RESIST PATTERN USING SAME}

The present invention relates to a resist underlayer film-forming composition containing a polymer type photoacid generator and a method of forming a resist pattern using a resist underlayer film formed from the composition, and more particularly, the composition capable of improving the shape of a resist pattern. And it relates to the pattern forming method.

Conventionally, wet developable reflection comprising a resist underlayer film forming composition containing a low molecular photoacid generator, for example, a polymer and / or oligomer soluble in a solvent system having an acid functional group together with a crosslinking agent and a photoacid generator. At least one type of repeating unit having a chromophore (chromophore) that forms a light-absorbing film composition (Patent Document 1) and light absorption, and a polymer comprising at least one type of repeating unit having a hydroxyl group and / or a carboxyl group, and a terminal vinyl ether group An antireflection film-forming composition (Patent Document 2) containing a crosslinking agent, and optionally a photoacid generator and / or an acid and / or a thermal acid generator, has been proposed and used.

However, in these antireflection film compositions, since a single low molecular compound is used as the photoacid generator, it is possible that the photoacid generator component is eluted (reached) in the resist, or a sublimation derived from the photoacid generator component is generated during firing. It is a problem. Elution to the resist contaminates the resist composition, which is a liquid, and therefore, remains in the lithographic printing apparatus of the photoacid generator component or adheres to the components, which adversely affects exposure and development such as underexposure and poor development. do. Further, the sublimate is subsequently adhered as a foreign matter on the antireflection film, which may adversely affect defects.

On the other hand, a technique for introducing a polymerized photoacid generator into a resist film is already known, for example, characterized in that it comprises a polymer polymerized with an onium salt of sulfonic acid having a polymerizable unsaturated bond as a photoacid generator. A resist material is proposed (patent document 3). This document also discloses a resist material of which the polymer further has a structure having a repeating unit having an oxygen leaving group and a repeating unit having an adhesive group. However, the resist material aims at providing a resist material which is very suitable for immersion lithography, and in this document, specific means and effects are suggested for application to a resist underlayer film for obtaining a pattern with high precision. Not.

In addition, an upper antireflection film composition containing a polymer of a photoacid generator, a polymer of an upper antireflection film, and an organic solvent has been proposed (Patent Document 4). The upper anti-reflective coating composition is applied on top of a photoresist film to form an upper anti-reflective film. The purpose of this document is to provide a composition of the upper anti-reflective film applicable to immersion lithography. Moreover, this document does not suggest whether the composition can be applied to dry lithography as a resist underlayer film.

Japanese Patent Publication No. 2007-536389 Japanese Patent Publication No. 2008-501985 Japanese Patent Publication No. 2006-178317 Japanese Patent Publication No. 2006-169499

Therefore, this invention is made | formed based on the said situation, The subject to be solved further achieves improvement of a resist pattern shape, such as being able to form a straight resist pattern easily also in a pattern bottom part. It is to provide a resist underlayer film-forming composition containing a polymer type photoacid generator which can be used, and a method of forming a resist pattern using a resist underlayer film formed from the composition.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, the present inventors introduced a photoacid generator as a structural unit of a polymer, and can efficiently supply an acid from a resist underlayer film to a resist bottom, and, as a resist of a photoacid generator, By making it possible to suppress the elution and sublimation of the resin, it is possible to easily form a straight resist pattern, and further improve the shape of the resist pattern, and furthermore, the adverse effect of the elution to the resist and the sublimation It has been found that the occurrence of problems caused by occurrence can be eliminated, and the present invention has been completed. In addition, by introducing a second component and a third component in addition to the photoacid generator component in the polymer and completing the functional polymer, the function and role of the resist underlayer film forming composition containing the functional polymer are diversified, and the resist is formed therefrom. It was also found that the functionality of the underlayer film can be improved.

That is, the resist underlayer film forming composition containing the polymer which has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-1) as a 1st viewpoint.

[Formula 1]

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.

In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.).}

As a 2nd viewpoint, the resist underlayer film forming composition containing the polymer which has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2), and a structural unit represented by a following formula (B). .

[Formula 2]

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.

In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.).

In formula (B), R <_1> represents a hydrogen atom or a methyl group, A <_1> represents -C (= O) O-, -O- or a direct bond, X <_1> is a C1-C8 alkyl group, aryl Group or an arylalkyl group, wherein the alkyl group, the aryl group or the arylalkyl group has at least one hydroxyl group, carboxyl group or epoxy group.

p and q show the injection ratio (mass%) of the raw material monomer for obtaining the structural unit contained in the said polymer, and p and q are the ranges of 0.05-0.95, respectively. However, p + q≤1 is satisfied.

As a 3rd viewpoint, the structural unit represented by the following formula (A-1) or the structural unit represented by the following formula (A-2), the structural unit represented by the following formula (B), and the structural unit represented by the following formula (C) A resist underlayer film forming composition containing a polymer having.

(3)

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.

In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.)

In formula (B), R <_1> represents a hydrogen atom or a methyl group, A <_1> represents -C (= O) O-, -O- or a direct bond, X <_1> is a C1-C8 alkyl group, aryl Group or an arylalkyl group, wherein the alkyl group, the aryl group or the arylalkyl group has at least one hydroxyl group, carboxyl group or epoxy group.

In formula (C), R <_1> represents a hydrogen atom or a methyl group, A <_2> represents -C (= O) O-, -O- or a direct bond, X <_2> some or all of the hydrogen atoms are substituted by the fluorine atom And an alkyl group having 1 to 8 carbon atoms.

p, q, and r represent the injection ratio (mass%) of the raw material monomer for obtaining the structural unit contained in the said polymer, and p, q, and r are the ranges of 0.05-0.95, respectively. However, p + q + r≤1 is satisfied.

Moreover, the polymer which does not have the photo-acid generator represented by said Formula (A-1) and Formula (A-2) as a structural unit is included in the resist underlayer film forming composition in any one of a 1st viewpoint thru | or a 3rd viewpoint. Can be. As such a polymer, an acrylic polymer, polyester, novolak is mentioned, for example.

As a 4th viewpoint, the resist underlayer film forming composition in any one of a 1st viewpoint thru | or a 3rd viewpoint which further contains a crosslinking agent, a crosslinking catalyst, and an organic solvent.

As a fifth aspect,

Applying and baking the resist underlayer film forming composition according to any one of the first to fourth aspects on a substrate having a film to be processed to form a pattern to form a resist underlayer film,

Forming a resist film on the formed resist underlayer film,

Irradiating the substrate on which the resist film is formed with radiation selected from the group consisting of KrF excimer laser, ArF excimer laser, extreme ultraviolet (EUV), and electron beam (EB),

Developing the resist film after irradiation to form a resist pattern, and

And transferring the pattern onto the substrate by dry etching using the formed resist pattern as a mask.

Since the resist underlayer film forming composition of this invention mix | blends the thing which introduce | transduced the photoacid generator as a structural unit of a polymer in a composition, in the resist underlayer film formed from this composition, an acid generate | occur | produces efficiently from a photoacid generator at the time of exposure. By supplying near the interface between the resist underlayer film and the resist film, more precise etching is possible, particularly at the bottom of the resist pattern, and a straight resist pattern can be easily formed. Can be. In addition, it is possible to prevent elution (riching) of the photoacid generator component, which is a problem when the conventional low molecular weight photoacid generator is applied, and to suppress sublimation of the photoacid generator component by the firing step.

Moreover, the resist underlayer film forming composition of this invention can improve the functionality of the resist underlayer film formed from the resist underlayer film forming composition by containing the polymer which introduced the functional monomer as a 2nd, 3rd component other than a photo-acid generator component. Will be.

In addition, the resist underlayer film formed from the resist underlayer film forming composition of the present invention has high sensitivity and high line edge roughness at high sensitivity and high resolution to radiation, particularly KrF excimer laser, ArF excimer laser, EUV, EB, and the like. The occurrence of intermixing can be reduced.

Hereinafter, each component is explained in full detail.

Solid content remove | excluding the organic solvent from the resist underlayer film forming composition of this invention is 0.5-10 mass%, for example.

As a polymer of the photo-acid generator contained in the resist underlayer film forming composition of this invention, it has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2).

[Formula 4]

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.

In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms). have.).}

Formula (A-1) is a polymer of a photoacid generator which is a sulfonium salt (cationic glass type) of sulfonic acid having a polymerizable unsaturated bond. In addition, said Formula (A-2) is a polymer of the photo-acid generator which is the sulfonate (anion free type) of sulfonium which has a polymerizable unsaturated bond.

The sulfonate salt of sulfonic acid having a polymerizable unsaturated bond and the sulfonate salt of a sulfonium having a polymerizable unsaturated bond are required to obtain a polymer contained in the resist underlayer film forming composition of the present invention as described above. I) and (II) can be illustrated.

[Chemical Formula 5]

In formula (I), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein said alkyl Some or all of the hydrogen atoms of the ethylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.).

In the formula (II), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group or 7 to 7 carbon atoms. 10 alkylphenylene groups (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom or may have one or more ether groups) .).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.).}

Examples of the sulfonic acid anion in the sulfonium salt of sulfonic acid represented by the general formula (I) include the following.

[Formula 6]

Moreover, the following can be illustrated as a cation of the sulfonium salt represented by the said General formula (I).

[Formula 7]

Examples of the sulfonium cation in the sulfonate salt of sulfonium represented by the general formula (II) include the following.

[Formula 8]

In addition, the following can be illustrated as an anion of the sulfonate represented by the said general formula (II).

[Formula 9]

Synthesis of the sulfonium salt of sulfonic acid represented by the general formula (I) is known and is disclosed, for example, in Japanese Patent Application Laid-Open No. 2009-091350 and Japanese Patent Publication No. 2009-091351.

Moreover, the synthesis | combination of the sulfonate of sulfonium represented by the said general formula (II) is also well-known, For example, Hengpeng Wu et al. Funct. Mater. 2001, 11, No. 4, August and the like.

The viscosity of the polymer which has a structural unit represented by the said Formula (A-1) or said Formula (A-2) is 1-100 cP normally.

In addition, a viscosity is the value measured with the VISCOMETER TV-20 made by TOKI SANGYO Co., Ltd ..

In the resist underlayer film forming composition of this invention, content of the polymer which has a structural unit represented by said Formula (A-1) or said Formula (A-2) is an example based on solid content of the said resist underlayer film forming composition. For example, it is 0.1-10 mass%. This polymer may be included in the resist underlayer film forming composition of the present invention as a main component of the solid content as well as an additive.

In addition, the polymer contained in the resist underlayer film forming composition of this invention is a structural unit represented by a following formula (B) other than the structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2). It can have

[Formula 10]

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.

In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.)

In formula (B), R <_1> represents a hydrogen atom or a methyl group, A <_1> represents -C (= O) O-, -O- or a direct bond, X <_1> is a C1-C8 alkyl group, aryl Group or an arylalkyl group, wherein the alkyl group, the aryl group or the arylalkyl group has at least one hydroxyl group, carboxyl group or epoxy group.

p and q show the injection ratio (mass%) of the raw material monomer for obtaining the structural unit contained in the said polymer, and p and q are the ranges of 0.05-0.95, respectively. However, p + q≤1 is satisfied.

The resist underlayer film forming composition of this invention introduce | transduces the structural unit represented by said formula (B) as a 2nd component other than the photo-acid generator component represented by said Formula (A-1) or said Formula (A-2) in a polymer. By including one polymer, the functionality of the resist underlayer film formed from the resist underlayer film forming composition can be improved.

As a 2nd component represented by said Formula (B), the resist formed from the resist underlayer film forming composition of this invention by introducing the structural unit which has a crosslinking site | part (-OH) represented by following formula (III), for example. The underlayer film can be imparted with a property as a thermal crosslinking film, and can be immobilized to the base polymer when a polymer having a photoacid generator component as a structural unit included in the resist underlayer film forming composition of the present invention is applied as an additive. Therefore, when applying a resist on the resist underlayer film, it is possible to suppress the leaching (elution) of the photoacid generator component or to suppress the sublimation of the photoacid generator component.

[Formula 11]

As a raw material monomer of the 2nd component represented by said Formula (B), For example, acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2, 3-dihydroxypropylacrylate, 3-chloro-2-hydroxyacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2,3 Dihydroxypropyl methacrylate, 3-chloro-2-hydroxymethacrylate, 4-hydroxystyrene, 4-hydroxyphenylacrylate, 4-hydroxyphenylmethacrylate, glycidyl acrylate, Glycidyl methacrylate is mentioned.

In order to improve the functionality of a resist underlayer film by improving a resist pattern shape to a straight shape, and introducing a 2nd component, p is 0.05-0.95 normally. In addition, q is 0.05-0.95 normally.

In addition, the viscosity of the polymer which has a structural unit represented by the said Formula (A-1) or said Formula (A-2), and the structural unit represented by the said Formula (B) is 1-100 cP.

In addition, a viscosity is the value measured by the TOKI SANGYO Co., Ltd., VISCOMETER TV-20.

In addition, the polymer contained in the resist underlayer film forming composition of this invention is a structural unit represented by a structural unit represented by a following formula (A-1), or a following formula (A-2), and a structural unit represented by a following formula (B). In addition, it may have a structural unit represented by the following formula (C).

[Chemical Formula 12]

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.

In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).

R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.

R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms). have.)

In formula (B), R <_1> represents a hydrogen atom or a methyl group, A <_1> represents -C (= O) O-, -O- or a direct bond, X <_1> is a C1-C8 alkyl group, aryl Group or an arylalkyl group, wherein the alkyl group, the aryl group or the arylalkyl group has at least one hydroxyl group, carboxyl group or epoxy group.

In formula (C), R <_1> represents a hydrogen atom or a methyl group, A <_2> represents -C (= O) O-, -O- or a direct bond, X <_2> some or all of the hydrogen atoms are substituted by the fluorine atom And an alkyl group having 1 to 8 carbon atoms.

p, q, and r represent the injection ratio (mass%) of the raw material monomer for obtaining the structural unit contained in the said polymer, and p, q, and r are the ranges of 0.05-0.95, respectively. However, p + q + r≤1 is satisfied.

The resist underlayer film forming composition of the present invention is the same as the second component described above as the third component, except for the photoacid generator component represented by the formula (A-1) or the formula (A-2) in the polymer. By including the polymer which introduce | transduced the structural unit shown by C), the functionality of the resist underlayer film formed from the resist underlayer film forming composition can be improved.

As a 3rd component represented by said Formula (C), surface energy is reduced by introducing the fluorine-type structural unit represented by following formula (IV), for example, and it is contained in the resist underlayer film forming composition of this invention. When a polymer having a generator component as a structural unit is applied as an additive, the photoacid generator component can be segregated effectively on the surface portion of the resist underlayer film. In addition, even a small amount of addition can effectively exhibit the efficacy as an acid.

[Formula 13]

As a raw material monomer of the 3rd component represented by said Formula (C), For example, 2,2,2- trifluoroethyl acrylate, 2,2,3,3- tetrafluoro propyl acrylate, 2,2, 3,3,3-pentafluoropropylacrylate, 2,2,3,3,4,4,4-heptafluorobutylacrylate, 2,2,3,3,4,4-hexafluorobutyl Acrylate, bis (2,2,2-trifluoromethyl) isopropylacrylate, 4-fluorophenylacrylate, 2,3,4,5,6-pentafluorophenylacrylate, 2,2, 2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2,2,3, 3,4,4,4-heptafluorobutyl methacrylate, 2,2,3,3,4,4-hexafluorobutyl methacrylate, bis (2,2,2-trifluoromethyl) iso Propyl methacrylate, 4-fluorophenyl methacrylate, 2,3,4,5,6-pentafluorophenyl methacrylate It can be given.

To improve the functionality of the resist underlayer film by improving the resist pattern shape to a straight shape and introducing the second component and the third component, p is usually 0.05 to 0.95. In addition, q is 0.05-0.95 normally. And r is usually 0.05 to 0.95.

In addition, the viscosity of the polymer which has a structural unit represented by the said Formula (A-1) or the said Formula (A-2), and the structural unit represented by the said Formula (B) and said Formula (C) is 1-100 cP.

In addition, a viscosity is the value measured with the VISCOMETER TV-20 by TOKI SANGYO Co., Ltd ..

Although it does not specifically limit as a synthesis | combining method of the polymer contained in the resist underlayer film forming composition of this invention, For example, the sulfonium salt of the sulfonic acid represented by said Formula (I) in said organic solvent, or said Formula (II). The polymerization initiator can be synthesized by adding a polymerization initiator to the sulfonate salt of sulfonium, the raw material monomer of the second component represented by the formula (B), and the raw material monomer of the third component represented by the formula (C). .

As this polymerization initiator, 2,2'- azobisisobutyronitrile, 2,2'- azobis (2, 4- dimethylvaleronitrile), dimethyl 2,2'- azobis (2, for example) -Methyl propionate), benzoyl peroxide, lauroyl peroxide, etc. can be mentioned, and it can superpose | polymerize by heating at 50-80 degreeC normally. The reaction time is usually 2 to 100 hours, or 5 to 30 hours.

The resist underlayer film forming composition of this invention may further contain a crosslinking agent.

Although it does not restrict | limit especially as such a crosslinking agent, The crosslinkable compound which has at least 2 crosslinking substituents is used preferably. As this crosslinking agent, the melamine type compound and substituted urea type compound which have crosslinking substituents, such as a methylol group and a methoxymethyl group, are mentioned, for example. Specifically, they are compounds, such as methoxymethylated glycoluril or methoxymethylated melamine, For example, they are tetramethoxymethylglycoluril, tetrabutoxymethylglycoluril, and hexamethoxymethylmelamine. Moreover, compounds, such as tetramethoxymethyl urea and tetrabutoxymethyl urea, are also mentioned.

In the resist underlayer film forming composition of this invention, content of the said crosslinking agent is 1-50 mass% based on solid content of this resist underlayer film forming composition.

Moreover, in order to accelerate crosslinking reaction, the resist underlayer film forming composition of this invention can contain a crosslinking catalyst.

As such a crosslinking catalyst, for example, sulfonic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid and pyridinium-p-toluenesulfonate, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid and hydroxybenzoic acid Carboxylic acid compounds;

In the resist underlayer film forming composition of this invention, content of the said crosslinking catalyst is 0.02-10 mass% based on solid content of this resist underlayer film forming composition.

As mentioned above, the resist underlayer film forming composition of this invention can be prepared by melt | dissolving each said component in the organic solvent, adding a polymerization initiator, and heat-polymerizing.

As such an organic solvent, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, Propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, methoxybutanol, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-hydroxy Ethyl propionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, Ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, acet Ethyl acid, butyl acetate, ethyl lactate, butyl lactate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and the like.

The organic solvents may be used alone or in combination of two or more thereof.

Moreover, the resist underlayer film forming composition of this invention may contain surfactant.

As this surfactant, For example, polyoxyethylene alkyl ethers, such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenol Polyoxyethylene alkylallyl ethers such as ether and polyoxyethylene nonylphenol ether, polyoxyethylene polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan Sorbitan fatty acid esters such as monooleate, sorbitan trioleate, sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, Polyoxyethylene sol such as polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate Nonionic surfactants such as non-fatty acid esters, EFTOP [registered trademark] EF301, EF303, EF352 (Mitsubishi Materials Electronic Chemicals Co., Ltd. (formerly manufactured by Jemco. Co., Ltd.), MEGAFAC [registered trademark] F171, F173, R-30 (manufactured by Dainippon Ink and Chemicals, Inc.), FLUORAD FC430, FC431 (manufactured by Sumitomo 3M Limited.), ASAHI GUARD [registered trademark] AG710, SURFLON [registered trademark] S-382, SC101, Fluorine-based surfactants such as SC102, SC103, SC104, SC105, and SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer-KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), and the like.

These surfactants may be used alone or in combination of two or more thereof.

In addition, when the said surfactant is used, content in the resist underlayer film forming composition of this invention is 3 mass% or less based on content in solid content of the said resist underlayer film forming composition, Preferably it is 1 mass%. It is below, More preferably, it is 0.5 mass% or less.

In addition, the resist underlayer film forming composition of this invention can also contain a rheology modifier, an adhesion | attachment adjuvant, etc. as needed, unless the effect of this invention is reduced.

Hereinafter, use of the resist underlayer film forming composition of this invention is demonstrated.

Substrate ｛For example, a semiconductor substrate such as silicon coated with silicon oxide film, a semiconductor substrate such as silicon nitride film or silicon oxynitride film coated, silicon nitride substrate, quartz substrate, glass substrate (alkali glass, low The resist underlayer film forming composition of this invention is apply | coated by suitable coating methods, such as a spinner and a coater, on alkali glass, a crystallized glass, a glass substrate with an ITO film | membrane, etc., and then heating, such as a hotplate, By baking by means, a resist underlayer film is formed.

As baking conditions, although it selects suitably from the baking temperature of 80-250 degreeC, and baking time 0.3-60 minutes, Preferably, they are baking temperature 130-250 degreeC and baking time 0.5-5 minutes.

Moreover, as a film thickness of the resist underlayer film of this invention, it is 0.005-3.0 micrometers, Preferably it is 0.01-1.0 micrometer, More preferably, it is 0.01-0.5 micrometer.

Thereafter, a photoresist film is formed on the resist underlayer film. Formation of a photoresist film can be performed by a general method, ie, application and baking of a photoresist solution onto a resist underlayer film.

The photoresist formed on the resist underlayer film obtained by the resist underlayer film forming composition of the present invention is not particularly limited as long as it is photosensitive to exposure light. As the photoresist, for example, a positive photoresist composed of a novolak resin and 1,2-naphthoquinone diazide sulfonic acid ester, a binder having a group which is decomposed by an acid to increase the alkali dissolution rate, and photoacid generation A chemically amplified photoresist made of an agent, a chemically amplified photoresist composed of a low molecular compound, an alkali-soluble binder and a photoacid generator that decomposes with an acid to increase the alkali dissolution rate, and an alkali dissolution rate is increased by an acid. And chemically amplified photoresists comprising a low molecular weight compound and a photoacid generator which are decomposed by a binder having a group and an acid to increase the alkali dissolution rate of the photoresist.

Specifically, brand name: APEX-X (made by Rohm and Hass electronics materials) (former Shipley company), brand name: PAR710 (made by Sumitomo Chemical Co., Ltd.), brand name: SEPR430 (Shin-Etsu Chemical Co. Ltd.). , Ltd.), etc. are mentioned.

In this invention, in the formation method of the photoresist pattern used for manufacture of a semiconductor manufacturing apparatus, exposure exposes through the mask (reticle) for forming a predetermined | prescribed pattern. KrF excimer laser, ArF excimer laser, etc. can be used for exposure. After exposure, post exposure baking is performed as needed. As conditions for post-exposure heating, it selects from heating temperature 80-150 degreeC and heating time 0.3-60 minutes suitably. A semiconductor device is manufactured by the process of exposing the semiconductor substrate covered with the resist underlayer film and the photoresist film using a photomask, and developing after that.

As a developing solution used for image development, For example, aqueous solution of alkali metal hydroxides, such as potassium hydroxide and sodium hydroxide, aqueous solution of quaternary ammonium hydroxides, such as tetramethyl ammonium hydroxide, tetraethyl ammonium hydroxide, and corin, ethanolamine, and propylamine And alkaline aqueous solutions, such as amine aqueous solutions, such as ethylenediamine, etc. are mentioned.

As image development conditions, it is suitably selected from image development temperature 5-50 degreeC and image development time 10-300 second. The resist underlayer film formed from the resist underlayer film forming composition of this invention can be easily developed at room temperature using the 2.38 mass% tetramethylammonium hydroxide aqueous solution widely used for image development of a photoresist.

Example

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in more detail, this invention is not limited to these Examples.

<Synthesis example 1>

2.80 g of triphenylsulfonium 2-methacryloyloxy-1,1-difluoroethanesulfonate (monomer 1) in a 100 mL flask (JP-A-2009-091350 and JP-A-2009-091351) 20.93 g of propylene glycol monomethyl ether was added to 2.10 g of 2-hydroxypropyl methacrylates and 2.10 g of 2,2,2-trifluoroethyl methacrylates. Subsequently, after shielding this reaction container, it heated at 70 degreeC, and the solution which melt | dissolved 0.07 g of 2,2'- azobisisobutyronitriles in 7.00 g of propylene glycol monomethyl ethers little by little under the nitrogen atmosphere was made into reaction container. It dripped in the inside. After completion of the dropwise addition, the mixture was reacted at 70 ° C for 24 hours to obtain a solution of a high molecular compound. The viscosity of the obtained solution was 57.8 cP (TOKI SANGYO CO., LTD., VISCOMETER® TV-20). This was set as polymer 1.

[Formula 14]

<Synthesis example 2>

2.80 g of trifluoromethanesulfonyl 4-dimethylsulfonylphenylmethacrylate (monomer 2) in a 100 mL flask (see Engengeng Wu et al., Ad. Funct. Mater. 2001, 11, No. 4, August) and 2- 20.93 g of ethyl lactate was added to 2.10 g of hydroxypropyl methacrylate and 2.10 g of 2,2,2-trifluoroethyl methacrylate. Next, after shielding this reaction container, it heated at 70 degreeC, and the solution which melt | dissolved 0.07 g of 2,2'- azobisisobutyronitrile in 7.00 g of ethyl lactates was dripped in the reaction container little by little under nitrogen atmosphere. . After completion of the dropwise addition, the mixture was reacted at 70 ° C for 24 hours to obtain a solution of a high molecular compound. The viscosity of the obtained solution was 55.0 cP (TOKI SANGYO CO., LTD., VISCOMETER® TV-20). This was referred to as polymer 2.

[Formula 15]

<Synthesis example 3>

4.00 g of nonafluorobutanesulfonyl 4-dimethylsulfonylphenylmethacrylate (monomer 3) in a 100 mL flask (see Engengeng Wu et al. Ad. Funct. Mater. 2001, 11, No. 4, August) and 2- 29.90 g of ethyl lactate was added to 3.00 g of hydroxypropyl methacrylates and 3.00 g of 2,2,2-trifluoroethyl methacrylates. Next, after shielding this reaction container, it heated at 70 degreeC, and the solution which melt | dissolved 0.10 g of 2,2'- azobisisobutyronitrile in 10.00 g of ethyl lactates was dripped in the reaction container little by little under nitrogen atmosphere. . After completion of the dropwise addition, the mixture was reacted at 70 ° C for 24 hours to obtain a solution of a high molecular compound. The viscosity of the obtained solution was 42.4 cP (TOKI SANGYO CO., LTD., VISCOMETER® TV-20). This was set as polymer 3.

[Formula 16]

<Synthesis example 4>

4.00 g of heptadecafluorooctanesulfonyl 4-dimethylsulfonylphenylmethacrylate (monomer 4) in a 100 mL flask (see Henppeng Wu et al. Adｖ.Funct. Mater. 2001, 11, No.4, August) and 2 29.90 g of ethyl lactate was added to 3.00 g of hydroxypropyl methacrylate and 3.00 g of 2,2,2-trifluoroethyl methacrylate. Next, after shielding this reaction vessel, it was heated to 70 ° C, and a solution in which 0.10 g of 2,2'-azobisisobutyronitrile was dissolved in 10.00 g of ethyl lactate was added dropwise into the reaction vessel under a nitrogen atmosphere. . After completion of the dropwise addition, the mixture was reacted at 70 ° C for 24 hours to obtain a solution of a high molecular compound. The viscosity of the obtained solution was 18.1 cP (TOKI SANGYO CO., LTD., VISCOMETER® TV-20). This was set as polymer 4.

[Formula 17]

<Synthesis example 5>

To a 300 mL flask, 89.70 g of ethyl lactate was added to 10.20 g of benzyl methacrylate, 9.90 g of 2-hydroxypropyl methacrylate, and 9.90 g of γ-butyrolactone methacrylate. Next, this reaction container was heated to 70 degreeC, and the solution which melt | dissolved 0.30 g of 2,2'- azobisisobutyronitrile in 30.00 g of ethyl lactates was dripped in the reaction container little by little under nitrogen atmosphere. After completion of the dropwise addition, the mixture was reacted at 70 ° C for 24 hours to obtain a solution of a high molecular compound. The weight average molecular weight Mw of the obtained solution was 26000 (polystyrene conversion). This was referred to as Polymer 5.

[Formula 18]

The said weight average molecular weight is a measurement result by gel permeation chromatography (GPC).

The GPC apparatus by Tosoh Corporation was used for the measurement.

Device name: GPC 'AS-8020

Eluent: N, N-dimethylformamide (DMF) + LiBr? H ₂ O (10 mmol)

Use column: Asahipak [registered trademark] (GF-710HG, GF-510HQ, GF-310HQ)

Flow rate: 0.600 ml / min

Column temperature: 40 degrees Celsius

<Example 1>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 1 0.15 g of propylene glycol monomethyl ether solution containing 0.03 g of the obtained high molecular compound (polymer 1) (5% by mass relative to the solid content of Polymer 5) was mixed, dissolved in 4.4 g of propylene glycol monomethyl ether and 10.2 g of ethyl lactate. It made into a solution. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Example 2>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 1 0.45 g of a propylene glycol monomethyl ether solution containing 0.09 g of the obtained high molecular compound (polymer 1) (15 mass% based on the solid content of Polymer 5) was mixed, dissolved in 4.6 g of propylene glycol monomethyl ether and 11.1 g of ethyl lactate. It made into a solution. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Example 3>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 2 0.14 g (5 mass% with respect to solid content of Polymer 5) containing 0.03 g of the obtained high molecular compound (polymer 2) was mixed, and dissolved in 4.5 g of propylene glycol monomethyl ether and 10.1 g of ethyl lactate to obtain a solution. . Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Example 4>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 3 0.14 g (5 mass% based on the solid content of Polymer 5) containing 0.03 g of the obtained high molecular compound (Polymer 3) was mixed, dissolved in 5.2 g of propylene glycol monomethyl ether acetate and 8.7 g of ethyl lactate to obtain a solution. did. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Example 5>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 3 0.43 g of ethyl lactate solution (15% by mass relative to the solid content of Polymer 5) containing 0.09 g of the obtained high molecular compound (polymer 3) was mixed, dissolved in 5.2 g of propylene glycol monomethyl ether acetate, and 8.5 g of ethyl lactate. did. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Example 6>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 4 0.14 g (5 mass% based on the solid content of Polymer 5) containing 0.03 g of the obtained high molecular compound (Polymer 4) was mixed, dissolved in 5.2 g of propylene glycol monomethyl ether acetate, and 8.7 g of ethyl lactate. did. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Example 7>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 4 0.43 g of ethyl lactate solution (15 mass% based on the solid content of Polymer 5) containing 0.09 g of the obtained high molecular compound (Polymer 4) was mixed, dissolved in 5.2 g of propylene glycol monomethyl ether acetate and 8.5 g of ethyl lactate. did. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Comparative Example 1>

To 3.00 g of an ethyl lactate solution containing 0.57 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.14 g of tetramethoxymethylglycoluril and 0.01 g of pyridinium-p-toluenesulfonate were mixed and propylene glycol monomethyl was added. It was dissolved in 5.2 g of ether acetate and 8.8 g of ethyl lactate to obtain a solution. Then, it filtered using the polyethylene microfilter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition solution.

<Comparative Example 2>

To 2.73 g of ethyl lactate solution containing 0.54 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.13 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 1 0.01 g of triphenylsulfonium 2-methacryloyloxy-1,1-difluoroethanesulfonate (monomer 1) which is a precursor compound of the obtained high molecular compound (polymer 1) is mixed, and 5.7 g of propylene glycol monomethyl ether It dissolved in 11.0 g of ethyl lactate to make a solution. Then, it filtered using the polyethylene microfilter of 0.1 micrometer of pore diameters, and prepared the resist underlayer film forming composition. In addition, the addition amount of the monomer 1 was 2 mass% with respect to the solid content of the polymer 5.

<Comparative Example 3>

To 2.73 g of ethyl lactate solution containing 0.54 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.13 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 1 0.03 g of triphenylsulfonium 2-methacryloyloxy-1,1-difluoroethanesulfonate (monomer 1) which is a precursor compound of the obtained high molecular compound (polymer 1) is mixed, and 5.7 g of propylene glycol monomethyl ether It dissolved in 11.1 g of ethyl lactate to make a solution. Then, it filtered using the polyethylene micro filter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition. In addition, the addition amount of the monomer 1 was 5 mass% with respect to the solid content of the polymer 5 like Example 1.

<Comparative Example 4>

To 2.73 g of an ethyl lactate solution containing 0.54 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.13 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 2 0.01 g of trifluoromethanesulfonyl 4-dimethylsulfonylphenyl methacrylate (monomer 2), which is a precursor compound of the obtained high molecular compound (polymer 2), is mixed, and dissolved in 5.7 g of propylene glycol monomethyl ether and 11.0 g of ethyl lactate. It was made into a solution. Then, it filtered using the polyethylene micro filter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition. In addition, the addition amount of the monomer 2 was 2 mass% with respect to the solid content of the polymer 5.

<Comparative Example 5>

To 2.73 g of an ethyl lactate solution containing 0.54 g of the polymer compound (polymer 5) obtained in Synthesis Example 5, 0.13 g of tetramethoxymethylglycoluril, 0.01 g of pyridinium-p-toluenesulfonate, and an additive were used in Synthesis Example 2 0.03 g of trifluoromethanesulfonyl 4-dimethylsulfonylphenyl methacrylate (monomer 2) which is a precursor compound of the obtained high molecular compound (polymer 2) is mixed, and dissolved in 5.7 g of propylene glycol monomethyl ether and 11.1 g of ethyl lactate. It was made into a solution. Then, it filtered using the polyethylene micro filter of 0.10 micrometer of pore diameters, and prepared the resist underlayer film forming composition. In addition, the addition amount of the monomer 2 was 5 mass% with respect to the solid content of the polymer 5 like Example 3.

[Sublimation quantitative examination]

The resist underlayer film-forming composition solution (Examples 1 to 4 and Comparative Examples 2 to 5) thus prepared was applied onto a silicon wafer by a spin coater, using a sublimation determination device described in International Publication No. 2007/111147. And the sublimation amount derived from the resist underlayer film forming composition which generate | occur | produce when heated for 60 second on the 205 degreeC hotplate were quantified. The results are shown in Table 1 and Table 2.

From the result of Table 1 and Table 2, the resist underlayer film forming composition of this invention contains the polymerized photoacid generator, and is compared with the resist underlayer film forming composition containing the conventional low molecular-type photoacid generator, and bake. It was confirmed that sublimation of the photoacid generator component could be suppressed at the time.

[Resist pattern formation test]

The resist underlayer film forming composition solution prepared as described above (Examples 1 to 8 and Comparative Examples 1 to 5) was applied onto a silicon wafer by Coater Developer (manufactured by Tokyo Electron Limited., CleanTrack-ACT8), and then 205 on a hot plate. By heating at 60 DEG C for 60 seconds, a resist underlayer film (film thickness of 0.08 mu m) for lithography was formed. The ArF lithography resist (TArF-P6111ME) solution was apply | coated to the upper layer of this resist underlayer film, and it heated on 130 degreeC for 60 second on the hotplate, and formed the resist film. The film was exposed to light using a ArF excimer laser exposure apparatus (S307E, manufactured by Nikon Corporation, NA = 0.85) through a mask in which a line and space was formed such that the line width of the resist was 0.08 μm and the space width was 0.10 μm. And 130 degreeC, it heated for 60 second (PEB), and developed for 60 second by 2.38 mass% aqueous solution of the tetramethylammonium hydroxide, and the resist pattern (Examples 1-8 and Comparative Examples 1-5) was obtained.

As for the obtained resist pattern, the pattern shape of the resist was observed using the scanning electron microscope (S-4800 made by Hitachi High-Technologies Corporation). The results are shown in Table 3.

From the results in Table 3, the resist underlayer film forming composition of the present invention is contained in the resist underlayer film formed from the composition under exposure conditions in an ArF excimer laser having a wavelength of 193 nm because the sublimation of the photoacid generator component is suppressed. As acid generated efficiently from the photoacid generator component thus obtained, it was confirmed that the resist pattern shape can be improved to a straight shape as compared with the conventional resist underlayer film.

As mentioned above, although embodiment of the resist underlayer film forming composition for lithography of this invention was described, the technical scope of this invention is not limited to the range as described in the said embodiment. Various changes or improvement can be added to the said embodiment.

Claims (6)

The resist underlayer film forming composition containing the polymer which has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2).
[Formula 1]

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.
In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).
R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.
R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.).}
The resist underlayer film forming composition containing the polymer which has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2), and a structural unit represented by a following formula (B).
(2)

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.
In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).
R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.
R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.)
In formula (B), R <_1> represents a hydrogen atom or a methyl group, A <_1> represents -C (= O) O-, -O- or a direct bond, X <_1> is a C1-C8 alkyl group, aryl Group or an arylalkyl group, wherein the alkyl group, the aryl group or the arylalkyl group has at least one hydroxyl group, carboxyl group or epoxy group.
p and q show the injection ratio (mass%) of the raw material monomer for obtaining the structural unit contained in the said polymer, and p and q are the ranges of 0.05-0.95, respectively. However, p + q≤1 is satisfied.
Resist containing the polymer which has a structural unit represented by a following formula (A-1) or a structural unit represented by a following formula (A-2), a structural unit represented by a following formula (B), and a structural unit represented by a following formula (C) Underlayer film forming composition.
(3)

In formula (A-1), R <_1> represents a hydrogen atom or a methyl group, R <_2> represents a C1-C8 alkylene group, a C4-C8 cycloalkylene group, or a phenylene group (wherein Some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group or the phenylene group may be substituted with fluorine atoms.
In the formula (A-2), R ₁ represents a hydrogen atom or a methyl group, R ₂ represents an alkylene group having 1 to 8 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, a phenylene group, or a carbon atom number 7-10 alkylphenylene group (wherein some or all of the hydrogen atoms of the alkylene group, the cycloalkylene group, the phenylene group or the alkylphenylene group may be substituted with a fluorine atom, and have at least one ether group) You can also).
R ₃ , R ₄ and R ₅ represent the same or different alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 8 carbon atoms or phenyl groups which may have substituents, and R ₃ and R ₄ , R ₃ and R ₅ , R ₄ and R ₅ may be bonded to each other to form a ring.
R ₆ represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group or a phenyl group having 4 to 8 carbon atoms (wherein some or all of the hydrogen atoms of the alkyl group, the cycloalkyl group or the phenyl group may be substituted with fluorine atoms) have.)
In formula (B), R <_1> represents a hydrogen atom or a methyl group, A <_1> represents -C (= O) O-, -O- or a direct bond, X <_1> is a C1-C8 alkyl group, aryl Group or an arylalkyl group, wherein the alkyl group, the aryl group or the arylalkyl group has at least one hydroxyl group, carboxyl group or epoxy group.
In formula (C), R <_1> represents a hydrogen atom or a methyl group, A <_2> represents -C (= O) O-, -O- or a direct bond, X <_2> some or all of the hydrogen atoms are substituted by the fluorine atom And an alkyl group having 1 to 8 carbon atoms.
p, q, and r represent the input ratio (mass%) of the raw material monomer for obtaining the structural unit contained in the said polymer, and p, q, and r are the ranges of 0.05-0.95, respectively. However, p + q + r≤1 is satisfied.
4. The method according to any one of claims 1 to 3,
A resist underlayer film forming composition wherein the polymer is an additive.
5. The method according to any one of claims 1 to 4,
A resist underlayer film forming composition further comprising a crosslinking agent, a crosslinking catalyst and an organic solvent.
The process of apply | coating and baking the resist underlayer film forming composition of any one of Claims 1-5 on the board | substrate which has a process target film which forms a pattern, and forming a resist underlayer film;
Forming a resist film on the formed resist underlayer film;
Irradiating the substrate on which the resist film is formed with radiation selected from the group consisting of KrF excimer laser, ArF excimer laser, extreme ultraviolet (EUV) and electron beam (EB);
Developing the resist film after irradiation to form a resist pattern; And
Transferring the pattern onto the substrate by dry etching using the formed resist pattern as a mask;
Method of manufacturing a semiconductor device.