JP5035151B2 - Resin composition for pattern inversion and method for forming inversion pattern - Google Patents

Description

  The present invention relates to a resin composition for pattern reversal and a method for forming a reversal pattern. More specifically, the present invention does not mix with the photoresist pattern formed on the substrate to be processed, can be embedded well between the photoresist patterns, and has excellent adhesion with the resist pattern. The present invention relates to a resin composition for pattern reversal excellent in oxygen ashing resistance and storage stability and a reversal pattern forming method using the same.

  In pattern formation when manufacturing semiconductor elements and the like, fine processing of a substrate made of an organic material or an inorganic material is performed by a pattern transfer method applying a lithography technique, a resist development process, and an etching technique (for example, (See Patent Document 1).

JP 2002-110510 A

However, as the integration of semiconductor elements and the like on a circuit board increases, the photoresist pattern formed on the substrate to be processed is miniaturized and the volume between the patterns is reduced. In the reverse pattern forming material used in the above, it is difficult to satisfactorily embed between the resist pattern patterns formed on the substrate to be processed.
Therefore, there is a demand for a reverse pattern forming material that is excellent in embedding properties. Further, such a reversal pattern forming material needs not to intermix with a photoresist pattern formed on a substrate to be processed, and has excellent oxygen ashing resistance, storage stability, and the like. It has been demanded. Furthermore, since the photoresist pattern is usually formed using an antireflection film, the reversal pattern forming material is required to have excellent adhesion to the resist pattern. However, at present, no specific material has been proposed as a material for forming the reverse pattern.

  The present invention has been made to overcome such problems, and can be satisfactorily embedded between the photoresist patterns without being mixed with the photoresist pattern formed on the substrate to be processed. It is another object of the present invention to provide a pattern reversal resin composition that is excellent in adhesion to a resist pattern and excellent in oxygen ashing resistance and storage stability, and a reversal pattern forming method using the same.

〔式（１）において、Ｒ^１は炭素数１〜４のアルキル基を示し、ｎは１〜４の整数である。〕

［２］前記ポリシロキサンが、アルコキシシランを出発原料として、水及び触媒の存在下で加水分解及び／又は縮合させて得られたものである前記［１］に記載のパターン反転用樹脂組成物。
［３］前記ポリシロキサンに含まれる全ての構成単位の合計を１００モル％とした場合に、上記式（１）で表される構成単位の含有割合が１〜５０モル％であり、上記式（２）で表される構成単位の含有割合が５０〜９９モル％である前記［１］又は［２］に記載のパターン反転用樹脂組成物。
［４］前記有機溶剤が、炭素数２〜１０の直鎖状又は分岐状のアルコールである前記［１］乃至［３］のいずれかに記載のパターン反転用樹脂組成物。
［５］〔１〕被加工基板上にフォトレジストパターンを形成する工程と、
〔２〕前記フォトレジストパターンのパターン間にパターン反転用樹脂組成物を埋め込む工程と、
〔３〕前記フォトレジストパターンを除去し、反転パターンを形成する工程と、を備える反転パターン形成方法であって、
前記パターン反転用樹脂組成物は、ポリシロキサンと、有機溶剤と、を含有しており、且つ、前記ポリシロキサンは、下記式（１）で表される構成単位と、下記式（２）で表される構成単位と、を含むことを特徴とする反転パターン形成方法。

〔式（１）において、Ｒ^１は炭素数１〜４のアルキル基を示し、ｎは１〜４の整数である。〕

［６］前記パターン反転用樹脂組成物を前記フォトレジストパターンのパターン間に埋め込んだ後、８０〜１８０℃で焼成する工程を備える前記［５］に記載の反転パターン形成方法。 Means for achieving the above object are as follows.
[1] [1] A step of forming a photoresist pattern on a substrate to be processed;
[2] A step of embedding a resin composition for pattern inversion between the patterns of the photoresist pattern;
[3] A pattern reversal resin composition used in a reversal pattern forming method comprising: removing the photoresist pattern and forming a reversal pattern,
Contains polysiloxane and an organic solvent,
The said polysiloxane contains the structural unit represented by following formula (1), and the structural unit represented by following formula (2), The resin composition for pattern inversion characterized by the above-mentioned.

In [Equation (1), ^{R 1} represents an alkyl group having 1 to 4 carbon atoms, n represents an integer of 1 to 4. ]

[2] The pattern reversal resin composition according to [1], wherein the polysiloxane is obtained by hydrolysis and / or condensation in the presence of water and a catalyst using alkoxysilane as a starting material.
[3] When the total of all the structural units contained in the polysiloxane is 100 mol%, the content of the structural unit represented by the above formula (1) is 1 to 50 mol%, and the above formula ( The resin composition for pattern reversal according to [1] or [2], wherein the content of the structural unit represented by 2) is 50 to 99 mol%.
[4] The resin composition for pattern reversal according to any one of [1] to [3], wherein the organic solvent is a linear or branched alcohol having 2 to 10 carbon atoms.
[5] [1] A step of forming a photoresist pattern on a substrate to be processed;
[2] A step of embedding a resin composition for pattern inversion between the patterns of the photoresist pattern;
[3] A step of forming a reverse pattern by removing the photoresist pattern, and a reverse pattern forming method comprising:
The resin composition for pattern reversal contains polysiloxane and an organic solvent, and the polysiloxane is represented by the structural unit represented by the following formula (1) and the following formula (2). And a reversal pattern forming method.

In [Equation (1), ^{R 1} represents an alkyl group having 1 to 4 carbon atoms, n represents an integer of 1 to 4. ]

[6] The reverse pattern forming method according to [5], further including a step of baking at 80 to 180 ° C. after the resin composition for pattern reversal is embedded between patterns of the photoresist pattern.

  The resin composition for pattern reversal of the present invention does not mix with a photoresist pattern formed on a substrate to be processed, can be satisfactorily embedded between the photoresist patterns, and has good adhesion to the resist pattern. In addition to being excellent, it is excellent in oxygen ashing resistance and storage stability. Therefore, the present invention can be used very suitably for the manufacture of LSI, which is expected to be further miniaturized in the future, particularly for the formation of fine contact holes and the like.

Hereinafter, embodiments of the present invention will be described in detail.
[1] Method for Forming Reverse Pattern The reverse pattern formation method in the present invention comprises: [1] a step of forming a photoresist pattern on a substrate to be processed (hereinafter referred to as “step [1]”); A step of embedding a resin composition for pattern reversal between resist pattern patterns (hereinafter referred to as “step [2]”), and [3] a step of removing the photoresist pattern to form a reversal pattern (hereinafter referred to as “step”). [3] ”).

In the step [1], a photoresist pattern (hereinafter also simply referred to as “resist pattern”) is formed on the substrate to be processed.
The formation method of this resist pattern is not specifically limited, It can form using a well-known photolithography process. For example, it can be formed as follows.
First, a resist composition solution is applied on the substrate to be processed and dried to form a photoresist film. Next, exposure is performed by irradiating a desired area of the formed resist film with radiation through a mask having a predetermined pattern. Thereafter, by developing the exposed portion, a predetermined pattern of a photoresist pattern can be formed.

  As the substrate to be processed, for example, a silicon wafer, a wafer coated with aluminum, or the like can be used. In order to maximize the potential of the resist composition solution described later on this substrate to be processed, as disclosed in Japanese Patent Publication No. 6-12458, etc., organic or inorganic antireflection A film may be formed in advance.

  As the resist composition solution, for example, a chemically amplified resist composition containing an acid generator or the like is dissolved in an appropriate solvent so as to have a solid content concentration of, for example, 0.1 to 20% by mass. After that, for example, those prepared by filtering with a filter having a pore diameter of about 30 nm can be used. A commercially available resist composition solution such as an ArF resist composition solution or a KrF resist composition solution may be used as it is. Further, the resist composition solution may be a positive type or a negative type.

The method for applying the resist composition solution is not particularly limited, and examples thereof include appropriate application means such as spin coating, cast coating, and roll coating.
Moreover, the drying means after apply | coating a resist composition solution is not specifically limited, For example, the solvent in a coating film can be volatilized by preheating. This heating condition is appropriately adjusted depending on the composition of the resist composition solution, but is usually about 30 to 200 ° C, preferably 50 to 150 ° C.
Furthermore, the thickness of the resist film obtained after drying is not particularly limited, but is usually 10 to 1000 nm, preferably 50 to 500 nm.

The radiation used for the exposure is appropriately selected from visible rays, ultraviolet rays, far ultraviolet rays, X-rays, charged particle beams, etc., depending on the type of acid generator and the like contained in the resist composition solution. Far ultraviolet rays represented by ArF excimer laser (wavelength 193 nm) or KrF excimer laser (wavelength 248 nm) are preferable.
Further, the exposure conditions such as the exposure amount are appropriately selected according to the composition of the resist composition solution, the type of additives, and the like.
Furthermore, it is preferable to perform heat treatment after the exposure. By this heat treatment, the dissociation reaction of the acid dissociable group in the resin component can smoothly proceed. This heating condition is appropriately selected depending on the composition of the resist composition solution, and the heating temperature is usually 30 to 200 ° C, preferably 50 to 170 ° C. The heating time is usually 10 to 300 seconds, preferably 30 to 180 seconds.

Examples of the developer used for the development include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, and di-n-propyl. Amine, triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo -An alkaline aqueous solution in which at least one of alkaline compounds such as [4.3.0] -5-nonene is dissolved is preferable.
An appropriate amount of a surfactant or the like can be added to the developer composed of the alkaline aqueous solution.
In addition, after developing with the developing solution which consists of alkaline aqueous solution, generally it wash | cleans with water and dries.

In the step [2], a resin composition for pattern inversion is embedded between the resist patterns.
Specifically, the pattern-reversing resin composition is applied onto the substrate to be processed on the substrate to be processed on which the resist pattern is formed by an appropriate application means such as spin coating, cast coating, or roll coating. Then, a pattern reversal resin composition is embedded between the resist patterns. The pattern reversal resin composition used in this step [2] will be described in detail later.

In the step [2], it is preferable to provide a drying step after embedding the resin composition for pattern reversal between the patterns of the resist pattern.
Although the said drying means is not specifically limited, For example, the organic solvent in a coating film can be volatilized by baking. Although this baking condition is suitably adjusted with the compounding composition of the resin composition for pattern inversion, baking temperature is 80-180 degreeC normally, Preferably it is 80-150 degreeC. When this baking temperature is 80-180 degreeC, the planarization process mentioned later, especially the planarization process by the wet etch back method can be performed smoothly. The heating time is usually 10 to 300 seconds, preferably 30 to 180 seconds.
The thickness of the pattern reversal resin film obtained after drying is not particularly limited, but is usually 10 to 1000 nm, preferably 50 to 500 nm.

In the step [3], the photoresist pattern is removed to form a reverse pattern.
Specifically, first, planarization processing for exposing the upper surface of the resist film is performed. Next, the resist pattern is removed by oxygen etching, and a predetermined reverse pattern is obtained.
As a planarization method used in the planarization process, an etching method such as dry etch back or wet etch back, a CMP method, or the like can be used. Of these, dry etch back and CMP are preferable. In addition, the processing conditions in planarization are not particularly limited, and can be adjusted as appropriate.
For the oxygen etching, a known resist stripping device such as an oxygen plasma ashing device or an ozone ashing device can be used.
The etching process conditions are not particularly limited and can be adjusted as appropriate.

Hereinafter, a specific example of the reverse pattern forming method of the present invention including the steps [1], [2] and [3] will be described with reference to FIG.
In the step [1], as shown in FIG. 1A, a resist composition solution is applied onto the substrate 1 on which the antireflection film 2 is formed, and a predetermined film is obtained through a drying step by heating or the like. A thick resist film 3 is formed. Then, after exposure by irradiation with radiation or the like is performed on a desired area of the resist film 3 through a mask having a predetermined pattern, a resist pattern 31 is formed by development (see FIG. 1B). .
Next, in the step [2], as shown in FIG. 1C, on the substrate 1 on which the pattern 31 is formed so that the resin composition for pattern reversal is embedded between the patterns of the resist pattern 31. The pattern reversal resin composition 4 is applied to the substrate, and the pattern reversal resin film 4 is formed through a drying process such as heating.
Thereafter, in the step [3], as shown in FIG. 1D, planarization is performed by means such as an etch back method or a CMP method so that the upper surface of the resist film 31 is exposed. Next, the reverse pattern 41 is formed by removing the pattern 31 by oxygen etching (see FIG. 1E).

[2] Resin composition for pattern reversal The resin composition for pattern reversal in the present invention contains polysiloxane and an organic solvent, and is used in the above-described reversal pattern forming method of the present invention.

(1) Polysiloxane The polysiloxane is a structural unit represented by the following formula (1) [hereinafter referred to as “structural unit (1)”. ] And a structural unit represented by the following formula (2) [hereinafter referred to as “structural unit (2)”. ] Is contained.

〔式（１）において、Ｒ^１は炭素数１〜４のアルキル基を示し、ｎは１〜４の整数である。〕

In [Equation (1), ^{R 1} represents an alkyl group having 1 to 4 carbon atoms, n represents an integer of 1 to 4. ]

<Structural unit (1)>
The alkyl group having 1 to 4 carbon atoms of R ¹ in the formula (1) may be linear or branched, and examples thereof include a methyl group, an ethyl group, an n-propyl group, and i-propyl. Group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.

Examples of the monomer that gives the structural unit (1) include a silane compound represented by the following formula (i).
R ² Si (OR ³ ) ₃ (i)
In [Equation (i), ^{R 2} represents a group represented by the following formula (a), ^{R 3} represents an alkyl group having 1 to 4 carbon atoms. ]

〔式（ａ）において、Ｒ^４は炭素数１〜４のアルキル基を示し、ｍは１〜４の整数である。〕

In [Formula (a), ^{R 4} represents an alkyl group having 1 to 4 carbon atoms, m is an integer of 1 to 4. ]

For R ⁴ in the formula (a), the description of R ¹ in the formula (1) can be applied as it is.
In addition, the alkyl group having 1 to 4 carbon atoms of R ³ in the formula (i) may be linear or branched. For example, a methyl group, an ethyl group, an n-propyl group, i -Propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.

Specific examples of the silane compound that gives the structural unit (1) include 3- (trimethoxysilyl) propyl methacrylate, 3- (triethoxysilyl) propyl methacrylate, and N-3- (methacryloxy-2-hydroxypropyl). -3-aminopropyltriethoxysilane, 2- (trimethoxysilyl) ethyl methacrylate, 2- (triethoxysilyl) ethyl methacrylate, trimethoxysilylmethyl methacrylate, triethoxysilylmethyl methacrylate, 3- [tris (trimethylsiloxy) silyl ] Propyl methacrylate, 3- [tris (dimethylvinylsiloxy)] propyl methacrylate, methacryloxypropyltris (methoxyethoxy) silane, 3- (trichlorosilyl) propyl methacrylate and the like. It is. Among these, 3- (trimethoxysilyl) propyl methacrylate, 3- (triethoxysilyl) propyl methacrylate, trimethoxysilylmethyl methacrylate, and the like are preferable from the viewpoint of ease of monomer synthesis.
In addition, these monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, only 1 type may be contained in the said polysiloxane, and the said structural unit (1) may be contained 2 or more types.

<Structural unit (2)>
Examples of the monomer that provides the structural unit (2) include a silane compound represented by the following formula (ii).
Si (OR ⁵ ) ₄ (ii)
[In Formula (ii), R ⁵ represents a monovalent organic group. ]

Examples of the monovalent organic group in R ⁵ of the formula (ii) include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, Examples thereof include an alkyl group which may have a substituent such as γ-aminopropyl group, γ-glycidoxypropyl group and γ-trifluoropropyl group. Among these, a methyl group and an ethyl group are preferable. Incidentally, it may be each R ⁵ is all the same, may be different for all or part.

Specific examples of the silane compound that gives the structural unit (2) include, for example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-iso-propoxysilane, tetra-n-butoxysilane, tetra- sec-butoxysilane, tetra-tert-butoxysilane, tetraphenoxysilane, tetrachlorosilane, tetraacetoxysilane, tetraisocyanatosilane, tetrakis (butoxyethoxyethoxy) silane, tetrakis (dimethylsiloxy) silane, tetrakis (ethoxyethoxy) silane, Tetrakis (2-ethylhexyloxy) silane, tetrakis (2-methacryloxyethoxy) silane, tetrakis (methoxyethoxyethoxy) silane, tetrakis (methoxyethoxy) silane, Rakisu (methoxypropoxy) silane, tetrakis (methyl ethyl ketone creaking Roh) silane, tetrakis (trichlorosilylethyl) silane, tetrakis (trimethylsiloxy) silane, tetrakis (vinyldimethylsiloxy) silane. Among these, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-iso-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxy are considered from the viewpoints of reactivity and easy handling of substances. Silane and the like are preferable.
In addition, these monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  In addition to the structural units (1) and (2), the polysiloxane is a structural unit represented by the following formula (3) [hereinafter referred to as “structural unit (3)”. ] And a structural unit represented by the following formula (4) [hereinafter referred to as “structural unit (4)”. ] May be further contained.

〔式（３）において、Ｒ^６は、水素原子、ヒドロキシル基、炭素数１〜５のアルキル基、又は−ＯＲ^７を表し、Ｒ^７は炭素数１〜５のアルキル基を表す。〕

In [Equation (3), ^{R 6} is a hydrogen atom, a hydroxyl group, an alkyl group of 1 to 5 carbon atoms, or an -OR ^{7, R 7} represents an alkyl group having 1 to 5 carbon atoms. ]

〔式（４）において、Ｒ^８は、炭素数１〜４のアルキル基を表す。〕

In [Equation (4), ^{R 8} represents an alkyl group having 1 to 4 carbon atoms. ]

<Structural unit (3)>
The alkyl group having 1 to 5 carbon atoms in R ⁶ of the formula (3) may be linear or branched, and examples thereof include a methyl group, an ethyl group, an n-propyl group, and i-propyl. Group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, pentyl group and the like.
In addition, when R ⁶ is —OR ⁷ , the alkyl group having 1 to 5 carbon atoms of R ⁷ may be linear or branched. For example, a methyl group, an ethyl group, Examples thereof include n-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, pentyl group and the like.

Examples of the monomer that gives the structural unit (3) include a silane compound represented by the following formula (iii).
R ⁹ Si (OR ¹⁰ ) ₃ (iii)
[In formula (iii), R ⁹ represents a group represented by the following formula (b), and R ¹⁰ represents a monovalent organic group. ]

〔式（ｂ）において、Ｒ^１１は、水素原子、ヒドロキシル基、直鎖状若しくは分岐状の炭素数１〜５のアルキル基、又は−ＯＲ^１２を表し、Ｒ^１２は直鎖状若しくは分岐状の炭素数１〜５のアルキル基を表す。〕

[In the formula (b), R ¹¹ represents a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 5 carbon atoms, or —OR ¹² , and R ¹² represents a linear or branched group. An alkyl group having 1 to 5 carbon atoms is represented. ]

For R ¹¹ and R ¹² in the formula (b), the description of R ⁶ and R ⁷ in the formula (3) can be applied as it is.
Examples of the monovalent organic group in R ¹⁰ of the formula (iii) include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group. And an alkyl group which may have a substituent such as a group, γ-aminopropyl group, γ-glycidoxypropyl group, γ-trifluoropropyl group, and the like. Among these, a methyl group and an ethyl group are preferable. Incidentally, it may be all each R ¹⁰ is the same, may be different for all or part.

  Specific examples of the silane compound that gives the structural unit (3) include 2-methylphenyltrimethoxysilane, 2-methylphenyltriethoxysilane, 2-methylphenyltri-n-propoxysilane, and 2-methyl. Phenyltri-iso-propoxysilane, 2-methylphenyltri-n-butoxysilane, 2-methylphenyltri-sec-butoxysilane, 2-methylphenyltri-tert-butoxysilane, 2-methylphenyltrichlorosilane, 2- Methylphenyltriacetoxysilane, 4-methylphenyltrimethoxysilane, 4-methylphenyltriethoxysilane, 4-methylphenyltri-n-propoxysilane, 4-methylphenyltri-iso-propoxysilane, 4-methylphenyltri- n-Butoki Silane, 4-methylphenyltri-sec-butoxysilane, 4-methylphenyltri-tert-butoxysilane, 4-methylphenyltrichlorosilane, 4-methylphenyltriacetoxysilane, 2-ethylphenyltrimethoxysilane, 2-ethyl Phenyltriethoxysilane, 2-ethylphenyltri-n-propoxysilane, 2-ethylphenyltri-iso-propoxysilane, 2-ethylphenyltri-n-butoxysilane, 2-ethylphenyltri-sec-butoxysilane, 2 -Ethylphenyltri-tert-butoxysilane, 2-ethylphenyltrichlorosilane, 2-ethylphenyltriacetoxysilane,

  4-ethylphenyltrimethoxysilane, 4-ethylphenyltriethoxysilane, 4-ethylphenyltri-n-propoxysilane, 4-ethylphenyltri-iso-propoxysilane, 4-ethylphenyltri-n-butoxysilane, 4 -Ethylphenyltri-sec-butoxysilane, 4-ethylphenyltri-tert-butoxysilane, 4-ethylphenyltrichlorosilane, 4-ethylphenyltriacetoxysilane, 4-propylphenyltrimethoxysilane, 4-propylphenyltriethoxy Silane, 4-propylphenyltri-n-propoxysilane, 4-propylphenyltri-iso-propoxysilane, 4-propylphenyltri-n-butoxysilane, 4-propylphenyltri-sec-butoxysilane, -Propylphenyltri-tert-butoxysilane, 4-propylphenyltrichlorosilane, 4-propylphenyltriacetoxysilane, 4-butylphenyltrimethoxysilane, 4-butylphenyltriethoxysilane, 4-butylphenyltri-n-propoxy Silane, 4-butylphenyltri-iso-propoxysilane, 4-butylphenyltri-n-butoxysilane, 4-butylphenyltri-sec-butoxysilane, 4-butylphenyltri-tert-butoxysilane, 4-butylphenyl Trichlorosilane, 4-butylphenyltriacetoxysilane, 4-methoxyphenyltrimethoxysilane, 4-methoxyphenyltriethoxysilane, 4-methoxyphenyltri-n-propoxysilane, 4-methoxyphenyl Lutri-iso-propoxysilane, 4-methoxyphenyltri-n-butoxysilane, 4-methoxyphenyltri-sec-butoxysilane, 4-methoxyphenyltri-tert-butoxysilane, 4-methoxyphenyltrichlorosilane, 4-methoxy Phenyltriacetoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltri-iso-propoxysilane, phenyltri-n-butoxysilane, phenyltri-sec-butoxysilane, phenyltri- Examples thereof include tert-butoxysilane, phenyltrichlorosilane, and phenyltriacetoxysilane.

Among these compounds, 4-methoxyphenyltrimethoxysilane, 4-methoxyphenyltriethoxysilane, 4-methoxyphenyltri-n-propoxysilane, 4-methoxyphenyltrimethylsilane are preferable from the viewpoint of ease of monomer synthesis. -Iso-propoxysilane, 4-methoxyphenyltri-n-butoxysilane, 4-methoxyphenyltri-sec-butoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltri-iso -Propoxysilane, phenyltri-n-butoxysilane, phenyltri-sec-butoxysilane and the like are preferable.
In addition, these monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, the said structural unit (3) may be contained only 1 type in the said polysiloxane, and may be contained 2 or more types.

<Structural unit (4)>
The alkyl group having 1 to 4 carbon atoms of R ⁸ in the formula (4) may be linear or branched. For example, a methyl group, an ethyl group, an n-propyl group, i- Examples include propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group and the like.

Examples of the monomer that gives the structural unit (4) include a silane compound represented by the following formula (iv).
R ¹³ Si (OR ¹⁴ ) ₃ (iv)
[In Formula (iv), R ¹³ represents a linear or branched alkyl group having 1 to 4 carbon atoms, and R ¹⁴ represents a monovalent organic group. ]

For R ¹³ in the formula (iv), the description of R ⁸ in the formula (4) can be applied as it is.
Examples of the monovalent organic group for R ¹⁴ include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, and a γ-aminopropyl group. And an alkyl group which may have a substituent such as a group, γ-glycidoxypropyl group and γ-trifluoropropyl group. Among these, a methyl group and an ethyl group are preferable. Incidentally, the respective R ¹⁴ may all be the same, may be different for all or part.

  Specific examples of the silane compound that gives the structural unit (4) include methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso-propoxysilane, and methyltri-n-butoxysilane. Methyltri-sec-butoxysilane, methyltri-tert-butoxysilane, methyltriphenoxysilane, methyltriacetoxysilane, methyltrichlorosilane, methyltriisopropenoxysilane, methyltris (dimethylsiloxy) silane, methyltris (methoxyethoxy) silane, Methyltris (methylethylketoxime) silane, methyltris (trimethylsiloxy) silane, methylsilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propyl Poxysilane, ethyltri-iso-propoxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, ethyltri-tert-butoxysilane, ethyltriphenoxysilane, ethylbis (trimethylsiloxy) silane, ethyldichlorosilane, ethyltriacetoxysilane Ethyltrichlorosilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxysilane, n-propyltri-iso-propoxysilane, n-propyltri-n-butoxysilane, n -Propyltri-sec-butoxysilane, n-propyltri-tert-butoxysilane, n-propyltriphenoxysilane, n-propyltriacetoxysilane, n-propyltrichlorosilane I-propyltrimethoxysilane, i-propyltriethoxysilane, i-propyltri-n-propoxysilane, i-propyltri-iso-propoxysilane, i-propyltri-n-butoxysilane, i-propyltri -Sec-butoxysilane, i-propyltri-tert-butoxysilane, i-propyltriphenoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-butyltri-n-propoxysilane, n-butyltri- iso-propoxysilane, n-butyltri-n-butoxysilane, n-butyltri-sec-butoxysilane, n-butyltri-tert-butoxysilane, n-butyltriphenoxysilane, n-butyltrichlorosilane, 2-methylpropyltri Methoxysilane, 2-methylpropyltriethoxysilane, 2-methylpropyltri-n-propoxysilane, 2-methylpropyltri-iso-propoxysilane, 2-methylpropyltri-n-butoxysilane, 2-methylpropyltri-sec-butoxy Silane, 2-methylpropyltri-tert-butoxysilane, 2-methylpropyltriphenoxysilane, 1-methylpropyltrimethoxysilane, 1-methylpropyltriethoxysilane, 1-methylpropyltri-n-propoxysilane, 1- Methylpropyltri-iso-propoxysilane, 1-methylpropyltri-n-butoxysilane, 1-methylpropyltri-sec-butoxysilane, 1-methylpropyltri-tert-butoxysilane, 1-methylpropyltriphenoxysila , T-butyltrimethoxysilane, t-butyltriethoxysilane, t-butyltri-t-propoxysilane, t-butyltri-iso-propoxysilane, t-butyltri-n-butoxysilane, t-butyltri-sec-butoxysilane , T-butyltri-tert-butoxysilane, t-butyltriphenoxysilane, t-butyltrichlorosilane, t-butyldichlorosilane and the like.

Among these, from the viewpoint of reactivity and easy handling of substances, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso-propoxysilane, methyltri-n-butoxysilane, methyltri- sec-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltri-iso-propoxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxysilane, n-propyltri-iso-propoxysilane, n-propyltri-n-butoxysilane, n-propyltri-sec-butoxysila Etc. are preferred.
In addition, these monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, the said structural unit (4) may be contained only 1 type in the said polysiloxane, and may be contained 2 or more types.

<Other structural units>
The polysiloxane may further contain other structural units in addition to the structural units (1) to (4).
Examples of the other structural units include dimethyldimethoxysilane, diethyldimethoxysilane, dipropyldimethoxysilane, diphenyldimethoxysilane, (3-acryloxypropyl) methyldimethoxysilane, di-tert-butyldichlorosilane, and diethoxydivinylsilane. , Di (3-methacryloxypropyl) dimethoxysilane, dimethyldiethoxysilane, dimesityldimethoxysilane, dimesityldichlorosilane, diisopropyldimethoxysilane, diisobutyldimethoxysilane, dimethyldiacetoxysilane, diethyldiethoxysilane, dicyclopentyl Dimethoxysilane, di-n-butyldichlorosilane, di-t-butyldichlorosilane, di-cyclohexyldichlorosilane, acetoxypropyldichlorosilane, 3-acryloxypropyl) methyldichlorosilane, allylhexyldichlorosilane, allylmethyldichlorosilane, allylphenyldimethoxysilane, aminopropylmethyldiethoxysilane, diphenyldiethoxysilane, diphenyldichlorosilane, dimethacryloxydimethoxysilane, t- Butylmethyldichlorosilane, t-butylphenyldichlorosilane, 2- (carbomethoxy) ethylmethyldichlorosilane, 2-cyanoethylmethyldichlorosilane, 3-cyanopropylmethyldichlorosilane, 3-cyanopropylmethyldimethoxysilane, 3-cyanopropyl Phenyldichlorosilane, cyclohexylethyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldichlorosilane, mercapto Tylmethyldiethoxysilane, 3-mercaptopropylmethyldimethoxysilane, isobutylmethyldimethoxysilane, phenylmethyldichlorosilane, ethylmethyldichlorosilane, 3-methacryloxypropylmethyldiethoxysilane, p-tolylmethyldichlorosilane, phenethylmethyldichlorosilane , Di (p-tolyl) dichlorosilane, di (3-glycidoxy) propyldimethoxysilane, di (3-glycidoxy) propyldiethoxysilane, (3-cyclohexenyl) propyldimethoxysilane Is mentioned.
In addition, only 1 type may be contained for this other structural unit, and 2 or more types may be contained.

The content ratio of the structural unit (1) in the polysiloxane is preferably 1 to 50 mol%, more preferably when the total of all the structural units contained in the polysiloxane is 100 mol%. It is 1-30 mol%, More preferably, it is 5-10 mol%. When this content is less than 1 mol%, there is a risk of poor adhesion to the resist pattern. On the other hand, when it exceeds 50 mol%, oxygen ashing resistance may be poor.
The content of the structural unit (2) is preferably 50 to 99 mol%, more preferably 50 to 80, when the total of all the structural units contained in the polysiloxane is 100 mol%. It is mol%, More preferably, it is 50-60 mol%. When this content is less than 50 mol%, oxygen ashing resistance may be poor. On the other hand, when it exceeds 99 mol%, the storage stability of the composition may be poor.

The content of the structural unit (3) is preferably 10 mol% or less, more preferably 0 to 7 mol%, when the total of all the structural units contained in the polysiloxane is 100 mol%. More preferably, it is 0-5 mol%.
The content of the structural unit (4) is preferably 50 mol% or less, more preferably 1 to 40 mol, when the total of all the structural units contained in the polysiloxane is 100 mol%. %, More preferably 1 to 30 mol%.
Furthermore, the content of the other structural units is preferably 10 mol% or less, more preferably 1 to 8 mol%, when the total of all the structural units contained in the polysiloxane is 100 mol%. More preferably, it is 1 to 5 mol%.

  The polystyrene-converted weight average molecular weight (hereinafter also referred to as “Mw”) of the polysiloxane measured by gel permeation chromatography (GPC) is preferably 500 to 100,000, more preferably 1,000 to 50,000, and still more preferably. Is 1000-10000.

Moreover, it is preferable that the silanol abundance ratio in the said polysiloxane is 1-2 times with respect to the Si-O-Si bond in resin, More preferably, it is 1-1.7 times, More preferably, it is 1-1. .5 times. A silanol abundance ratio of 1 to 2 is preferable because of good storage stability.
This silanol abundance ratio can be measured by Si ²⁹ -NMR.

  In addition, the said polysiloxane may be contained only 1 type in the resin composition for pattern inversion in this invention, and may be contained 2 or more types.

(2) Organic solvent The organic solvent is not particularly limited as long as it can dissolve the polysiloxane and does not dissolve the photoresist pattern formed in advance on the substrate to be processed. Specific examples include alcohols, ethers, esters, and the like, and those containing these. Among these, alcohol is preferable.
In addition, this organic solvent may be comprised only from 1 type of components, and the mixture of 2 or more types of components may be sufficient as it.

As said alcohol, C2-C10 alcohol is preferable. The alcohol having 2 to 10 carbon atoms may be linear or branched. For example, ethanol, 1-propanol, 2-propanol, ethylene glycol, propylene glycol, glycerin, 1-butanol, 2 -Butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1,4-butanediol, pentanol, 1-methyl-1-butanol, 2-methyl-1-butanol, 3-methyl-1 -Butanol, cyclopentanol, hexanol, 4-methyl-2-pentanol, cyclohexanol, heptanol, cycloheptanol, octyl alcohol, nonyl alcohol, decyl alcohol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, Examples include ethylene glycol monomethyl ether, triethylene glycol monomethyl ether, 4-methoxy-1-butanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and propylene glycol monophenyl ether. .
Among these, 1-butanol, 2-butanol, pentanol, cyclopentanol, hexanol, cyclohexanol, 4-methyl-2-pentanol, heptanol, cycloheptanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether , Propylene glycol monopropyl ether is preferable, 1-butanol, 2-butanol, pentanol, cyclopentanol, hexanol, cyclohexanol, 4-methyl-2-pentanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene Glycol monopropyl ether is more preferred.

Examples of the ether include diethyl ether, dipropyl ether, dibutyl ether, dipentyl ether, diisopentyl ether and the like.
Furthermore, examples of the ester include methyl lactate and ethyl lactate.

  One type of these organic solvents may be contained in the resin composition for pattern reversal in the present invention, or two or more types thereof may be contained.

(3) Other Additives In addition to the polysiloxane and the organic solvent, the resin composition for pattern reversal in the present invention can contain other additives such as a surfactant and a crosslinking agent.

(4) Method for Preparing Pattern Reversal Resin Composition The method for preparing the pattern reversal resin composition in the present invention is not particularly limited. For example, hydrolysis and hydrolysis are performed in the presence of water and a catalyst using alkoxysilane as a starting material. Polysiloxane is obtained by condensation. More specifically, the starting material is dissolved in a solvent, and water is intermittently or continuously added to the solution. At this time, the catalyst may be dissolved or dispersed in the solvent in advance, or may be dissolved or dispersed in the added water. Moreover, the temperature for performing a hydrolysis reaction and / or a condensation reaction is 0-100 degreeC normally. Examples of the alkoxysilane that is the starting material include monomers that give the respective structural units [the structural units (1) to (4) and other structural units] in the aforementioned polysiloxane.
Subsequently, the resin composition for pattern inversion can be prepared by mixing the obtained polysiloxane, the organic solvent, and, if necessary, the other additive. At this time, the solid content concentration of the polysiloxane can be adjusted as appropriate, and can be, for example, 1 to 30% by mass, particularly 5 to 20% by mass.

  Although it does not specifically limit as water for performing the said hydrolysis and / or condensation, It is preferable to use ion-exchange water. The water is used in an amount of 0.25 to 3 mol, preferably 0.3 to 2.5 mol, per mol of alkoxyl group of the alkoxysilane used. By using water in an amount in the above range, there is no possibility that the uniformity of the formed coating film will be lowered, and there is little possibility that the storage stability of the composition will be lowered.

The solvent used for synthesizing the polysiloxane is not particularly limited as long as it is a solvent used for this kind of application. For example, the thing similar to the said organic solvent can be mentioned.
Examples of the catalyst include metal chelate compounds, organic acids, inorganic acids, organic bases, and inorganic bases. Among these, when an organic base is used, the abundance ratio of silanol in the polysiloxane can be reduced, so that a composition having good storage stability can be obtained.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In addition, the description of “part” and “%” in the description of this example is based on mass unless otherwise specified.

[1] Preparation of resin composition for pattern reversal (Examples 1 to 4 and Comparative Examples 1 and 2) The resin compositions for pattern reversal of Examples 1 to 4 and Comparative Examples 1 to 2 were prepared as follows. did. In the present embodiment, it was measured weight average molecular weight and Si 29 ^-NMR in the following manner. Further, in this example, the following compounds (M-1) to (M-4) were used as monomers for synthesizing polysiloxane.
(1) Weight average molecular weight (Mw)
Tosoh GPC columns (trade name "G2000HXL", trade name "G3000HXL", trade name "G4000HXL" 1), flow rate: 1.0 mL / min, elution solvent: tetrahydrofuran, column temperature : Measured by gel permeation chromatography (GPC) using monodisperse polystyrene as a standard under analysis conditions of 40 ° C.
(2) Si ²⁹ -NMR
Nuclear magnetic resonance spectrometer manufactured by JEOL Ltd., internal standard: tetramethylsilane, solvent: heavy DMSO [(D ₃ C) ₂ S═O], measurement temperature: Si ²⁹ -NMR measurement under measurement conditions of 25 ° C. Carried out.

<Example 1>
An aqueous tetraammonium hydroxide solution was prepared by dissolving 1.82 g of tetramethylammonium hydroxide in 5.47 g of water by heating. Then, in a flask containing 7.29 g of the prepared tetraammonium hydroxide aqueous solution, 2.27 g of water, and 20 g of methanol, a condenser tube and 3- (trimethoxysilyl) propyl methacrylate [the compound (M-1)] 1 .17 g (9.47 mol%), phenyltrimethoxysilane [said compound (M-2)] 0.50 g (5.07 mol%), methyltrimethoxysilane [said compound (M-3)] 2.04 g (30.12 mol%), 4.19 g (55.35 mol%) of tetramethoxysilane [the compound (M-4)], and a dropping funnel containing 25 g of methanol were set. Subsequently, after heating to 40 degreeC with an oil bath, the monomer methanol solution containing the monomer of compound (M-1)-(M-4) was dripped slowly, and it was made to react at 40 degreeC for 1 hour. After completion of the reaction, the flask containing the reaction solution was allowed to cool.
Thereafter, 2.50 g of maleic anhydride was dissolved in 9.18 g of water and 9.18 g of methanol and a dropping funnel containing 21 g of a maleic acid methanol solution separately prepared was set and dropped into the reaction solution which had been allowed to cool. And stirred for 15 minutes. Next, 25 g of 4-methyl-2-pentenone was added and then set in an evaporator, and the reaction solvent and methanol produced by the reaction were removed to obtain a 4-methyl-2-pentenone resin solution.
And after moving the obtained resin solution to a separating funnel, the water washing which added 40 g of water was performed twice. To the 4-methyl-2-pentenone resin solution transferred from the separatory funnel to the 4-methyl-2-pentenone resin solution, 25 g of 4-methyl-2-pentanol was added and set in an evaporator to remove 4-methyl-2-pentenone and remove the resin. 27 g of solution was obtained (base catalyst method).
In addition, the content rate of solid content (resin) in the obtained resin solution was 13.6% as a result of measuring by the baking method. Moreover, the weight average molecular weight (Mw) of solid content (resin) was 4000. Furthermore, as a result of Si ²⁹ -NMR measurement, the abundance ratio of silanol in the resin was 1.2 times that of Si—O—Si bond.
Next, 22.06 g of the reaction product (resin solution) obtained as described above is dissolved in 37.94 g of 4-methyl-2-pentanol, and this solution is filtered through a filter having a pore size of 0.2 μm. Thus, the resin composition for pattern reversal of Example 1 was obtained.

<Example 2>
As a monomer, 1.17 g (7.71 mol%) of the compound (M-1), 3.2 g (38.48 mol%) of the compound (M-3), and 5. 5 of the compound (M-4). 26 g of a resin solution was obtained in the same manner as in Example 1 except that 0 g (53.81 mol%) was used.
In addition, the content rate of solid content (resin) in the obtained resin solution was 13.1% as a result of measuring by the baking method. Moreover, the weight average molecular weight (Mw) of solid content (resin) was 4500. Furthermore, as a result of Si ²⁹ -NMR measurement, the abundance ratio of silanol in the resin was 1.2 times that of Si—O—Si bond.
Next, 21.05 g of the reaction product (resin solution) was dissolved in 34.10 g of 4-methyl-2-pentanol, and this solution was further filtered through a filter having a pore size of 0.2 μm. A resin composition for reversal was obtained.

<Example 3>
An aqueous oxalic acid solution was prepared by dissolving 0.45 g of oxalic acid in 21.6 g of water by heating.
Thereafter, 1.17 g (9.47 mol%) of 3- (trimethoxysilyl) propyl methacrylate [said compound (M-1)], 0.50 g of phenyltrimethoxysilane [said compound (M-2)] (5. 07 mol%), methyltrimethoxysilane [the compound (M-3)] 2.04 g (30.12 mol%), tetramethoxysilane [the compound (M-4)] 4.19 g (55.35 mol%). ), And a flask containing 53.5 g of propylene glycol-1-ethyl ether were set with a condenser and a dropping funnel containing an aqueous oxalic acid solution prepared in advance. Subsequently, after heating to 60 degreeC with an oil bath, the oxalic acid aqueous solution was dripped slowly, and it was made to react at 60 degreeC for 4 hours. After completion of the reaction, the flask containing the reaction solution was allowed to cool and then set in an evaporator, and methanol produced by the reaction was removed to obtain 48 g of a resin solution (acid catalyst method).
In addition, the content rate of solid content (resin) in the obtained resin solution was 15.3% as a result of measuring by the baking method. Moreover, the weight average molecular weight (Mw) of solid content (resin) was 2100. Furthermore, as a result of Si ²⁹ -NMR measurement, the abundance ratio of silanol in the resin was 1.4 times that of the Si—O—Si bond.
Next, 14.89 g of the above reaction product (resin solution) was dissolved in 45.56 g of 4-methyl-2-pentanol, and this solution was further filtered through a filter having a pore size of 0.2 μm, whereby the pattern of Example 3 was obtained. A resin composition for reversal was obtained.

<Example 4>
As a monomer, 1.17 g (7.71 mol%) of the compound (M-1), 3.2 g (38.48 mol%) of the compound (M-3), and 5. 5 of the compound (M-4). 46 g of a resin solution was obtained in the same manner as in Example 3 except that 0 g (53.81 mol%) was used.
In addition, the content rate of solid content (resin) in the obtained resin solution was 15.1% as a result of measuring by the baking method. Moreover, the weight average molecular weight (Mw) of solid content (resin) was 2400. Furthermore, as a result of Si ²⁹ -NMR measurement, the abundance ratio of silanol in the resin was 1.3 times that of the Si—O—Si bond.
Next, 15.15 g of the above reaction product (resin solution) was dissolved in 30.30 g of 4-methyl-2-pentanol, and this solution was further filtered through a filter having a pore diameter of 0.2 μm. A resin composition for reversal was obtained.

<Comparative Example 1>
As a monomer, 0.99 g (4.98 mol%) of the compound (M-2), 3.4 g (24.90 mol%) of the compound (M-3), and 10.10 g of the compound (M-4). 48 g of a resin solution was obtained in the same manner as in Example 3 except that 7 g (70.12 mol%) was used.
In addition, the content rate of solid content (resin) in the obtained resin solution was 16.3% as a result of measuring by the baking method. Moreover, the weight average molecular weight (Mw) of solid content (resin) was 1200. Furthermore, as a result of Si ²⁹ -NMR measurement, the abundance ratio of silanol in the resin was 3.2 times that of the Si—O—Si bond.
Next, 14.72 g of the reaction product (resin solution) was dissolved in 45.28 g of 4-methyl-2-pentanol, and this solution was further filtered through a filter having a pore size of 0.2 μm, whereby the pattern of Comparative Example 1 was obtained. A resin composition for reversal was obtained.

<Comparative Example 2>
As a monomer, 0.99 g (4.98 mol%) of the compound (M-2), 3.4 g (24.90 mol%) of the compound (M-3), and 10.10 g of the compound (M-4). 25 g of a resin solution was obtained in the same manner as in Example 1 except that 7 g (70.12 mol%) was used.
In addition, the content rate of solid content (resin) in the obtained resin solution was 13.8% as a result of measuring by the baking method. Moreover, the weight average molecular weight (Mw) of solid content (resin) was 4700. Furthermore, as a result of Si ²⁹ -NMR measurement, the abundance ratio of silanol in the resin was 1.6 times that of the Si—O—Si bond.
Next, 16.08 g of the above reaction product (resin solution) was dissolved in 28.30 g of 4-methyl-2-pentanol, and this solution was filtered with a filter having a pore size of 0.2 μm, whereby the pattern of Comparative Example 2 was obtained. A resin composition for reversal was obtained.

  In addition, the compounding quantity of each monomer, the polymerization method of polysiloxane, and the weight average molecular weight of polysiloxane used in the preparation of the resin compositions for pattern reversal in Examples 1 to 4 and Comparative Examples 1 and 2 Table 1 summarizes the abundance ratios of silanols and silanols.

[2] Performance evaluation Each performance evaluation was performed as follows about each resin composition for pattern inversion in Examples 1-4 and Comparative Examples 1-2. The evaluation results are shown in Table 2.
(1) Intermixing with a photoresist film A resist composition solution [trade name “AR230JN” manufactured by JSR Corporation] was applied on the surface of a silicon wafer by a spin coater, and then was applied on a hot plate at 126 ° C. by 90%. The substrate was dried for 2 seconds to obtain a substrate on which a 170 nm thick resist film was formed. Subsequently, each resin composition for pattern inversion of Examples 1-4 and Comparative Examples 1-2 was apply | coated on the said resist film. Next, after immersing in a 2.38% tetramethylammonium hydroxide aqueous solution for 30 seconds to remove the inversion resin composition, the thickness of the resist film was measured with a spectroscopic ellipsometer.
Then, the difference between the film thickness and the initial film thickness was evaluated as “◯” when the difference was less than 50 mm, and “×” when the difference was 50 mm or more, and the intermixing property with the photoresist film was evaluated.

(2) Embeddability in resist pattern An antireflection film material [trade name “ARC29” manufactured by Nissan Chemical Industries, Ltd.] was applied on the surface of a silicon wafer by a spin coater, and then was applied on a hot plate at 205 ° C. for 60 hours. What was dried for 2 seconds and formed an antireflection film (resist underlayer film) having a film thickness of 77 nm was used as a substrate to be processed.
Next, a resist composition solution [manufactured by JSR Corporation, trade name “AR230JN”] was applied onto the resist underlayer film, and dried at 126 ° C. for 90 seconds. At this time, the film thickness of the resist film was controlled to 205 nm. Thereafter, using an ArF excimer laser irradiation apparatus (manufactured by Nikon Corporation), the resist film is formed through an ArF excimer laser (wavelength: 193 nm) through a quartz mask having a line and space pattern of 0.130 μm. The processed substrate was irradiated with 16.5 mJ. Next, the substrate to be processed was heated at 126 ° C. for 90 seconds. Thereafter, development was performed with a 2.38% tetramethylammonium hydroxide aqueous solution for 40 seconds to form a photoresist pattern on the substrate.
Next, by applying the pattern reversal resin compositions of Examples 1 to 4 and Comparative Examples 1 and 2 on the photoresist pattern and between the patterns with a spin coater and drying on a hot plate at 120 ° C. for 60 seconds. A pattern reversal resin film made of a pattern reversal resin composition having a thickness of 150 nm was formed.
Then, the cross section of the obtained substrate was observed with a scanning electron microscope (SEM), and when the resin composition for pattern reversal was embedded between the resist patterns with no gaps, “◯” was given, and the void was The case where it occurred was evaluated as “x”, and the embedding property in the resist pattern was evaluated.

(3) Adhesion with resist pattern After applying a material for an antireflection film [trade name “ARC29” manufactured by Nissan Chemical Industries, Ltd.] on the surface of a silicon wafer with a spin coater, the material is applied on a hot plate at 205 ° C. for 60 hours. What was dried for 2 seconds and formed an antireflection film (resist underlayer film) having a film thickness of 77 nm was used as a substrate to be processed.
Next, a resist composition solution [manufactured by JSR Corporation, trade name “AIM5056JN”] was applied onto the resist underlayer film, and dried at 90 ° C. for 60 seconds. At this time, the film thickness of the resist film was controlled to 120 nm. Thereafter, using an ArF excimer laser irradiation apparatus (manufactured by Nikon Corporation), an ArF excimer laser (wavelength: 193 nm) is passed through a quartz mask having a 90 nm line and space pattern. The processed substrate was irradiated with 27.0 mJ. Next, the substrate to be processed was heated at 115 ° C. for 60 seconds. Thereafter, development processing was performed with a 2.38% tetramethylammonium hydroxide aqueous solution for 30 seconds to form a photoresist pattern on the substrate.
Next, by applying the pattern reversal resin compositions of Examples 1 to 4 and Comparative Examples 1 and 2 on the photoresist pattern and between the patterns with a spin coater and drying on a hot plate at 120 ° C. for 60 seconds. A pattern reversal resin film made of a pattern reversal resin composition having a thickness of 150 nm was formed.
Then, when a cross section of the obtained substrate is observed with a scanning electron microscope (SEM), peeling is not confirmed between the resist pattern and each pattern reversal resin film formed between the resist patterns. Was evaluated as “○” and “×” when peeling was confirmed, and the adhesion to the resist pattern was evaluated.

(4) Oxygen ashing resistance Oxygen ashing for 15 seconds at 300 W using the barrel type oxygen plasma ashing device “PR-501” (manufactured by Yamato Kagaku Co., Ltd.) on the resin film for pattern reversal formed as described above. Processed.
The case where the difference between the film thickness of the pattern reversal resin film before treatment and the film thickness of the pattern reversal resin film after treatment is 5 nm or less is “◯”, and the case where it exceeds 5 nm is “x”. The oxygen ashing resistance was evaluated.

(5) Storage stability The resin composition for pattern inversion of each of Examples 1 to 4 and Comparative Examples 1 to 2 was applied to the surface of a silicon wafer using a spin coater under the conditions of a rotation speed of 1500 rpm and 20 seconds. Thereafter, the pattern inversion resin film was formed by drying on a hot plate at 120 ° C. for 60 seconds. Subsequently, about the obtained resin film for pattern inversion, an optical film thickness meter (KLA-Tencor company make, model number "UV-1280SE") was used to measure the film thickness at 9 points, and the average film thickness was measured. Asked.
Further, after each of the pattern reversal resin compositions of Examples 1 to 4 and Comparative Examples 1 to 2 was stored at a temperature of 23 ° C. for 1 month, a pattern reversal resin film was formed in the same manner as described above to form a film thickness. And the average film thickness was determined.
Then, an average film thickness T ₀ of the previous pattern reversal resin film storage, the difference between the average thickness T of the pattern reversal resin film after storage (T-T ₀₎ determined, the relative average thickness T ₀ The ratio [(T−T ₀ ) / T ₀ ] of the magnitude of the difference is calculated as the film thickness change rate, and when the value is 5% or less, “◯” is given, and when it exceeds 5%, “×” is given. As a result, the storage stability was evaluated. In addition, it was set as "x" also when the gel-like deposit which can be confirmed visually is deposited.

[3] Effects of Examples As is clear from Table 2, the resin compositions for pattern reversal of Examples 1 to 4 were formed on the resist film without mixing with the resist film formed on the substrate. It was confirmed that the film was satisfactorily embedded between the patterns, had excellent adhesion to the patterns, and was excellent in oxygen ashing resistance and storage stability.

It is a schematic diagram explaining the formation method of a reverse pattern.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1; Substrate to be processed, 2; Antireflection film, 3; Resist film, 31; Resist pattern, 4; Resin film for pattern inversion, 41;

Claims (6)

[1] A step of forming a photoresist pattern on a substrate to be processed;
[2] A step of embedding a resin composition for pattern inversion between the patterns of the photoresist pattern;
[3] A pattern reversal resin composition used in a reversal pattern forming method comprising: removing the photoresist pattern and forming a reversal pattern,
Contains polysiloxane and an organic solvent,
The said polysiloxane contains the structural unit represented by following formula (1), and the structural unit represented by following formula (2), The resin composition for pattern inversion characterized by the above-mentioned.

In [Equation (1), ^{R 1} represents an alkyl group having 1 to 4 carbon atoms, n represents an integer of 1 to 4. ]

  The resin composition for pattern reversal according to claim 1, wherein the polysiloxane is obtained by hydrolysis and / or condensation in the presence of water and a catalyst using alkoxysilane as a starting material.   When the total of all the structural units contained in the polysiloxane is 100 mol%, the content ratio of the structural unit represented by the above formula (1) is 1 to 50 mol%, and the above formula (2) The resin composition for pattern reversal according to claim 1 or 2, wherein the content ratio of the structural unit represented is 50 to 99 mol%.   The resin composition for pattern reversal according to any one of claims 1 to 3, wherein the organic solvent is a linear or branched alcohol having 2 to 10 carbon atoms. [1] A step of forming a photoresist pattern on a substrate to be processed;
[2] A step of embedding a resin composition for pattern inversion between the patterns of the photoresist pattern;
[3] A step of forming a reverse pattern by removing the photoresist pattern, and a reverse pattern forming method comprising:
The resin composition for pattern reversal contains polysiloxane and an organic solvent, and the polysiloxane is represented by the structural unit represented by the following formula (1) and the following formula (2). And a reversal pattern forming method.

In [Equation (1), ^{R 1} represents an alkyl group having 1 to 4 carbon atoms, n represents an integer of 1 to 4. ]

  The reverse pattern forming method according to claim 5, further comprising a step of baking at 80 to 180 ° C. after the resin composition for pattern reversal is embedded between the patterns of the photoresist pattern.

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