JP2010117439A - Positive radiation-sensitive composition, method of forming hardening pattern, and hardening pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive radiation-sensitive composition or the like that has a good pattern shape, has no pattern deformation by hardening treatment, and forms a hardening pattern of low dielectric constant required with further high integration and further increase of layers of a semiconductor element etc. <P>SOLUTION: This positive radiation-sensitive composition contains (A) polymer obtained by performing hydrolysis condensation of at least a kind of hydrolysis silane compound selected from hydrolysis silane compound expressed with formula (1) and hydrolysis silane compound expressed with formula (2), (B) a radiation sensitive base generator, and (C) a solvent, and its pH is in an acid side. In the formulae, R is hydrogen atom, fluorine atom, 1-5C alkyl group of a straight chain or branch shape, cyano group, cyano alkyl group, or alkyl carbonyl oxy group, each of R<SP>1</SP>and R<SP>2</SP>is monovalent organic group, and a shows an integer of 1-3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a positive radiation sensitive composition, a cured pattern forming method, and a cured pattern. More specifically, the present invention relates to a positive radiation sensitive composition capable of forming a cured pattern having a low relative dielectric constant, a cured pattern forming method using the composition, and a cured pattern obtained by the cured pattern forming method.

Conventionally, a silica (SiO ₂ ) film formed by a vacuum process such as a CVD method has been frequently used as an interlayer insulating film in a semiconductor element or the like.
In recent years, for the purpose of forming an interlayer insulating film having a more uniform film thickness, a coating type insulating film called SOG (Spin on Glass) film, which is mainly composed of a hydrolysis product of tetraalkoxysilane, is also available. It is used (for example, refer patent document 1). In addition, with the high integration of semiconductor elements and the like, an interlayer insulating film having a low relative dielectric constant called polyorganosiloxane called organic SOG has been developed (for example, see Patent Documents 2 and 3).

  However, with further higher integration and multi-layering of semiconductor elements and the like, better electrical insulation between conductors is required, and accordingly, an interlayer insulating film having a lower relative dielectric constant has been demanded. Yes.

Further, the processing of the interlayer insulating film is usually performed by repeating the pattern transfer process. In general, first, many different mask material layers are formed on an interlayer insulating film layer, and a photosensitive resin composition is coated on the uppermost portion thereof. Next, a desired circuit pattern is formed on the photosensitive resin composition by reduction projection exposure and development, and then the pattern is transferred to the sequentially stacked mask material layers. Finally, after the pattern is transferred from the mask material layer to the interlayer insulating film layer, the mask material layer is removed and the interlayer insulating film is processed (see, for example, Patent Document 4).
As described above, processing of an interlayer insulating film that is generally performed is very laborious and is a very inefficient process, and thus an improvement method is required. The invention described in Patent Document 4 describes an interlayer insulating film having a low relative dielectric constant capable of forming a pattern, but is still not sufficient in terms of pattern shape and pattern deformation.

Japanese Patent Laid-Open No. 5-36684 Japanese Patent Laid-Open No. 2003-3120 JP 2005-213492 A JP 2004-212983 A

  The present invention has been made in view of the above circumstances, and has excellent pattern shape, no pattern deformation due to curing treatment, and low dielectric constant required for further integration and multi-layering of semiconductor elements and the like. An object of the present invention is to provide a positive-type radiation-sensitive composition capable of forming a cured pattern having a high rate, a cured pattern forming method using the same, and a cured pattern obtained by the cured pattern forming method.

〔一般式（１）において、Ｒは水素原子、フッ素原子、炭素数１〜５の直鎖状若しくは分岐状のアルキル基、シアノ基、シアノアルキル基、又はアルキルカルボニルオキシ基を表し、Ｒ^１は１価の有機基を表し、ａは１〜３の整数を示す。〕

〔一般式（２）中、Ｒ^２は１価の有機基を示す。〕
［２］ｐＨが１〜４である前記［１］に記載のポジ型感放射線性組成物。
［３］更に、（Ｄ）熱酸発生剤を含む前記［１］又は［２］に記載のポジ型感放射線性組成物。
［４］前記（Ｂ）感放射線性塩基発生剤が、ベンジルカルバメート化合物、及びｏ−カルバモイルヒドロキシアミン類から選ばれる少なくとも一種である前記［１］乃至［３］のいずれかに記載のポジ型感放射線性組成物。
［５］前記（Ａ）重合体のゲルパーミエーションカラムクロマトグラフィーによるポリスチレン換算の重量平均分子量が、１０００〜１００００である前記［１］乃至［４］のいずれかに記載のポジ型感放射線性組成物。
［６］前記（Ｂ）感放射線性塩基発生剤の含有量が、前記（Ａ）重合体を１００質量部とした場合に、１〜１０質量部である前記［１］乃至［５］のいずれかに記載のポジ型感放射線性組成物。
［７］（１）前記［１］乃至［６］のいずれかに記載のポジ型感放射線性組成物を基板に塗布し、被膜を形成する工程と、
（２）得られた被膜をベークする工程と、
（３）ベークされた被膜を露光する工程と、
（４）露光された被膜をベークする工程と、
（５）得られた被膜を現像液で現像し、ポジ型パターンを形成する工程と、
（６）得られたポジ型パターンに、高エネルギー線照射及び加熱のうちの少なくとも一方の硬化処理を施し、硬化パターンを形成する工程と、を備えていることを特徴とする硬化パターン形成方法。
［８］前記［７］に記載の硬化パターン形成方法によって得られることを特徴とする硬化パターン。
［９］比誘電率が１．５〜３である前記［８］に記載の硬化パターン。 The present invention is as follows.
[1] (A) at least one hydrolyzable silane compound selected from the hydrolyzable silane compound represented by the following general formula (1) and the hydrolyzable silane compound represented by the following general formula (2) A polymer obtained by hydrolytic condensation;
(B) a radiation sensitive base generator;
(C) a positive radiation-sensitive composition containing a solvent,
A positive radiation-sensitive composition characterized in that the pH is acidic.

[In General Formula (1), R represents a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a cyano group, a cyanoalkyl group, or an alkylcarbonyloxy group, and R ¹ represents Represents a monovalent organic group, and a represents an integer of 1 to 3; ]

[In General Formula (2), R ² represents a monovalent organic group. ]
[2] The positive radiation sensitive composition according to [1], wherein the pH is 1 to 4.
[3] The positive radiation sensitive composition according to [1] or [2], further comprising (D) a thermal acid generator.
[4] The positive feeling according to any one of [1] to [3], wherein (B) the radiation sensitive base generator is at least one selected from benzyl carbamate compounds and o-carbamoylhydroxyamines. Radiation composition.
[5] The positive radiation sensitive composition according to any one of [1] to [4], wherein the polymer (A) has a polystyrene-reduced weight average molecular weight of 1,000 to 10,000 by gel permeation column chromatography. object.
[6] Any of [1] to [5], wherein the content of the (B) radiation-sensitive base generator is 1 to 10 parts by mass when the polymer (A) is 100 parts by mass. A positive radiation sensitive composition according to claim 1.
[7] (1) A step of applying the positive radiation-sensitive composition according to any one of [1] to [6] to a substrate to form a film;
(2) a step of baking the obtained film;
(3) exposing the baked coating;
(4) baking the exposed coating;
(5) developing the obtained film with a developer to form a positive pattern;
(6) A cured pattern forming method comprising: subjecting the obtained positive pattern to a curing process of at least one of high energy ray irradiation and heating to form a cured pattern.
[8] A cured pattern obtained by the cured pattern forming method according to [7].
[9] The cured pattern according to [8], wherein the relative dielectric constant is 1.5 to 3.

The positive-type radiation-sensitive composition of the present invention has radiation-sensitive properties, can be patterned, has no pattern deformation due to curing treatment, has an excellent pattern shape, and has a low dielectric constant curing. A pattern can be easily formed. Therefore, it can be used not only as a material for fine processing of semiconductor elements such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM, but also as an interlayer insulating film material, particularly including a copper damascene process. Useful for semiconductor devices.
Further, the cured pattern forming method of the present invention can be suitably used in a processing process that requires an interlayer insulating film having a low relative dielectric constant material, and greatly improves the efficiency of the processing process using a conventional interlayer insulating film. Can be improved.

  Hereinafter, embodiments of the present invention will be described in detail. In the present specification, “(meth) acryl” means “acryl” or “methacryl”, and “(meth) acrylate” means “acrylate” or “methacrylate”.

[1] Positive-type radiation-sensitive composition The positive-type radiation-sensitive composition of the present invention comprises (A) a polymer obtained by hydrolytic condensation of a specific hydrolyzable silane compound [hereinafter referred to as “polymer (A ) ". And (B) a radiation-sensitive base generator [hereinafter also referred to as “base generator (B)”. ] And (C) solvent [hereinafter referred to as “solvent (C)”. And containing.

[1-1] Polymer (A)
The polymer (A) is a hydrolyzable silane compound represented by the following general formula (1) (hereinafter also referred to as “compound (1)”), and a hydrolysis represented by the following general formula (2). It is obtained by hydrolytic condensation of at least one hydrolyzable silane compound selected from a functional silane compound (hereinafter also referred to as “compound (2)”).

〔一般式（１）において、Ｒは水素原子、フッ素原子、炭素数１〜５の直鎖状若しくは分岐状のアルキル基、シアノ基、シアノアルキル基、又はアルキルカルボニルオキシ基を表し、Ｒ^１は１価の有機基を表し、ａは１〜３の整数を示す。〕

[In General Formula (1), R represents a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a cyano group, a cyanoalkyl group, or an alkylcarbonyloxy group, and R ¹ represents Represents a monovalent organic group, and a represents an integer of 1 to 3; ]

〔一般式（２）中、Ｒ^２は１価の有機基を示す。〕

[In General Formula (2), R ² represents a monovalent organic group. ]

<Compound (1)>
Examples of the linear or branched alkyl group having 1 to 5 carbon atoms in R of the general formula (1) include a methyl group, an ethyl group, a propyl group, and a butyl group. In addition, one or two or more hydrogen atoms in these alkyl groups may be substituted with a fluorine atom or the like.
Examples of the cyanoalkyl group in R include a cyanoethyl group and a cyanopropyl group.
Furthermore, examples of the alkylcarbonyloxy group in R include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, a butylcarbonyloxy group, a vinylcarbonyloxy group, and an allylcarbonyloxy group.
When a plurality of Rs are present (that is, when a is 2 or 3), all Rs may be the same, or all or some of them may be different.

The monovalent organic group represented by R ¹ in the general formula (1), for example, an alkyl group, an alkenyl group, an aryl group, an allyl group, a glycidyl group, and the like. Among these, an alkyl group and an aryl group are preferable.
As said alkyl group, a C1-C5 linear or branched alkyl group is mentioned, for example. Specific examples include a methyl group, an ethyl group, a propyl group, and a butyl group. In addition, one or two or more hydrogen atoms in these alkyl groups may be substituted with a fluorine atom or the like.
Examples of the aryl group include a phenyl group, a naphthyl group, a methylphenyl group, an ethylphenyl group, a chlorophenyl group, a bromophenyl group, and a fluorophenyl group. Among these, a phenyl group is preferable.
Examples of the alkenyl group include a vinyl group, a propenyl group, a 3-butenyl group, a 3-pentenyl group, and a 3-hexenyl group.

  Specific examples of the compound (1) represented by the general formula (1) include, for example, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltriisopropoxysilane, methyltri-n-butoxy. Silane, methyltri-sec-butoxysilane, methyltri-tert-butoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltriisopropoxysilane, ethyltri-n-butoxysilane , Ethyltri-sec-butoxysilane, ethyltri-tert-butoxysilane, ethyltriphenoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxy N-propyltriisopropoxysilane, n-propyltri-n-butoxysilane, n-propyltri-sec-butoxysilane, n-propyltri-tert-butoxysilane, n-propyltriphenoxysilane, isopropyltrimethoxy Silane, isopropyltriethoxysilane, isopropyltri-n-propoxysilane, isopropyltriisopropoxysilane, isopropyltri-n-butoxysilane, isopropyltri-sec-butoxysilane, isopropyltri-tert-butoxysilane, isopropyltriphenoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-butyltri-n-propoxysilane, n-butyltriisopropoxysilane, n-butyltri-n-butoxy Emissions, n- butyltri -sec- butoxysilane, n- butyltri -tert- butoxysilane, n- butyl triphenoxy silane,

  sec-butyltrimethoxysilane, sec-butylisotriethoxysilane, sec-butyltri-n-propoxysilane, sec-butyltriisopropoxysilane, sec-butyltri-n-butoxysilane, sec-butyltri-sec-butoxysilane, sec-butyltri-tert-butoxysilane, sec-butyltriphenoxysilane, tert-butyltrimethoxysilane, tert-butyltriethoxysilane, tert-butylto-n-propoxysilane, tert-butyltriisopropoxysilane, tert-butyltri -N-butoxysilane, tert-butyltri-sec-butoxysilane, tert-butyltri-tert-butoxysilane, tert-butyltriphenoxysilane, dimethyldimethoxy Silane, dimethyldiethoxysilane, dimethyldi-n-propoxysilane, dimethyldiisopropoxysilane, dimethyldi-n-butoxysilane, dimethyldi-sec-butoxysilane, dimethyldi-tert-butoxysilane, dimethyldiphenoxysilane, diethyldimethoxysilane, Diethyldiethoxysilane, diethyldi-n-propoxysilane, diethyldiisopropoxysilane, diethyldi-n-butoxysilane, diethyldi-sec-butoxysilane, diethyldi-tert-butoxysilane, diethyldiphenoxysilane, di-n-propyldimethoxy Silane, di-n-propyldiethoxysilane, di-n-propyldi-n-propoxysilane, di-n-propyldiisopropoxysilane, di-n-propyldi-n-but Shishiran, di -n- propyl di -sec- butoxysilane, di -n- propyl di -tert- butoxysilane, di -n- propyl di - phenoxy silane,

  Diisopropyldimethoxysilane, diisopropyldiethoxysilane, diisopropyldi-n-propoxysilane, diisopropyldiisopropoxysilane, diisopropyldi-n-butoxysilane, diisopropyldi-sec-butoxysilane, diisopropyldi-tert-butoxysilane, diisopropyldiphenoxy Silane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-butyldi-n-propoxysilane, di-n-butyldiisopropoxysilane, di-n-butyldi-n-butoxysilane , Di-n-butyldi-sec-butoxysilane, di-n-butyldi-tert-butoxysilane, di-n-butyldi-phenoxysilane, di-sec-butyldimethoxysilane, di-sec-butyldiethoxy Run, Di-sec-butyldi-n-propoxysilane, di-sec-butyldiisopropoxysilane, di-sec-butyldi-n-butoxysilane, di-sec-butyldi-sec-butoxysilane, di-sec-butyldi -Tert-butoxysilane, di-sec-butyldi-phenoxysilane, di-tert-butyldimethoxysilane, di-tert-butyldiethoxysilane, di-tert-butyldi-n-propoxysilane, di-tert-butyldiiso Examples include propoxysilane, di-tert-butyldi-n-butoxysilane, di-tert-butyldi-sec-butoxysilane, di-tert-butyldi-tert-butoxysilane, and di-tert-butyldi-phenoxysilane.

Among these compounds (1), methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso-propoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, dimethyldimethoxysilane, dimethyldi Ethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane and the like are preferable.
In addition, these compounds (1) may be used individually by 1 type, and may be used in combination of 2 or more type.

<Compound (2)>
As the monovalent organic group in R ² of the general formula (2), the description of the monovalent organic group in R ¹ of the general formula (1) can be applied as it is.

Specific examples of the compound (2) represented by the general formula (2) include, for example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-iso-propoxysilane, tetra-n-butoxysilane, Examples include tetra-sec-butoxysilane, tetra-tert-butoxysilane, and tetraphenoxysilane.
Among these, tetramethoxysilane and tetraethoxysilane are preferable.
In addition, these compounds (2) may be used individually by 1 type, and may be used in combination of 2 or more type.

<Other compounds>
As the hydrolyzable silane compound for obtaining the polymer (A), it is preferable to use only a hydrolyzable silane compound selected from the compounds (1) and (2). In addition to 1) and (2), a hydrolyzable silane compound represented by the following general formula (3) (hereinafter also referred to as “other compound (3)”) may be used in combination.

〔一般式（３）中、Ｒ^３〜Ｒ^６は同一又は異なり、それぞれ１価の有機基を表し、ｘ及びｙは同一又は異なり、０〜２の数を示し、Ｒ^７は酸素原子、フェニレン基、又は−（ＣＨ_２）_ｎ−で表される基（ここで、ｎは１〜６の整数である）を表し、ｚは０又は１を示す。〕

[In General Formula (3), R ^{3 to} R ⁶ are the same or different and each represents a monovalent organic group, x and y are the same or different, and represent a number of 0 to 2, R ⁷ is an oxygen atom, phenylene Represents a group or a group represented by — (CH ₂ ) _n — (wherein n is an integer of 1 to 6), and z represents 0 or 1. ]

As the monovalent organic group in R ^{3 to} R ⁶ of the general formula (3), the description of the monovalent organic group in R ¹ of the general formula (1) can be applied as it is.
Specific examples of the compound represented by the general formula (3) and z = 0 include, for example, hexamethoxydisilane, hexaethoxydisilane, hexaphenoxydisilane, 1,1,1,2,2 -Pentamethoxy-2-methyldisilane, 1,1,1,2,2-pentaethoxy-2-methyldisilane, 1,1,1,2,2-pentaphenoxy-2-methyldisilane, 1,1,1 , 2,2-pentamethoxy-2-ethyldisilane, 1,1,1,2,2-pentaethoxy-2-ethyldisilane, 1,1,1,2,2-pentaphenoxy-2-ethyldisilane, , 1,1,2,2-pentamethoxy-2-phenyldisilane, 1,1,1,2,2-pentaethoxy-2-phenyldisilane, 1,1,1,2,2-pentaphenoxy-2- Phenyl Silane, 1,1,2,2-tetramethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraphenoxy-1 , 2-dimethyldisilane, 1,1,2,2-tetramethoxy-1,2-diethyldisilane, 1,1,2,2-tetraethoxy-1,2-diethyldisilane, 1,1,2,2- Tetraphenoxy-1,2-diethyldisilane, 1,1,2,2-tetramethoxy-1,2-diphenyldisilane, 1,1,2,2-tetraethoxy-1,2-diphenyldisilane, 1,1, 2,2-tetraphenoxy-1,2-diphenyldisilane,

  1,1,2-trimethoxy-1,2,2-trimethyldisilane, 1,1,2-triethoxy-1,2,2-trimethyldisilane, 1,1,2-triphenoxy-1,2,2-trimethyl Disilane, 1,1,2-trimethoxy-1,2,2-triethyldisilane, 1,1,2-triethoxy-1,2,2-triethyldisilane, 1,1,2-triphenoxy-1,2,2 -Triethyldisilane, 1,1,2-trimethoxy-1,2,2-triphenyldisilane, 1,1,2-triethoxy-1,2,2-triphenyldisilane, 1,1,2-triphenoxy-1 1,2-diphenyldisilane, 1,2-dimethoxy-1,1,2,2-tetramethyldisilane, 1,2-diethoxy-1,1,2,2-tetramethyldisilane, 1,2-dipheno 1,1,2,2-tetramethyldisilane, 1,2-dimethoxy-1,1,2,2-tetraethyldisilane, 1,2-diethoxy-1,1,2,2-tetraethyldisilane, 1, 2-diphenoxy-1,1,2,2-tetraethyldisilane, 1,2-dimethoxy-1,1,2,2-tetraphenyldisilane, 1,2-diethoxy-1,1,2,2-tetraphenyldisilane 1,2-diphenoxy-1,1,2,2-tetraphenyldisilane and the like.

  Among these, hexamethoxydisilane, hexaethoxydisilane, 1,1,2,2-tetramethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraethoxy-1,2-dimethyldisilane, 1 , 1,2,2-tetramethoxy-1,2-diphenyldisilane, 1,2-dimethoxy-1,1,2,2-tetramethyldisilane, 1,2-diethoxy-1,1,2,2-tetra Methyldisilane, 1,2-dimethoxy-1,1,2,2-tetraphenyldisilane, 1,2-diethoxy-1,1,2,2-tetraphenyldisilane and the like are preferable.

  Furthermore, specific examples of the compound represented by the general formula (3) and z = 1 include, for example, bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, bis (tri-n -Propoxysilyl) methane, bis (tri-iso-propoxysilyl) methane, bis (tri-n-butoxysilyl) methane, bis (tri-sec-butoxysilyl) methane, bis (tri-tert-butoxysilyl) methane, 1,2-bis (trimethoxysilyl) ethane, 1,2-bis (triethoxysilyl) ethane, 1,2-bis (tri-n-propoxysilyl) ethane, 1,2-bis (tri-iso-propoxy) Silyl) ethane, 1,2-bis (tri-n-butoxysilyl) ethane, 1,2-bis (tri-sec-butoxysilyl) ethane, 1,2 Bis (tri-tert-butoxysilyl) ethane, 1- (dimethoxymethylsilyl) -1- (trimethoxysilyl) methane, 1- (diethoxymethylsilyl) -1- (triethoxysilyl) methane, 1- (di -N-propoxymethylsilyl) -1- (tri-n-propoxysilyl) methane, 1- (di-iso-propoxymethylsilyl) -1- (tri-iso-propoxysilyl) methane, 1- (di-n -Butoxymethylsilyl) -1- (tri-n-butoxysilyl) methane, 1- (di-sec-butoxymethylsilyl) -1- (tri-sec-butoxysilyl) methane, 1- (di-tert-butoxy Methylsilyl) -1- (tri-tert-butoxysilyl) methane, 1- (dimethoxymethylsilyl) -2- (trimethoxysilyl) 1- (diethoxymethylsilyl) -2- (triethoxysilyl) ethane, 1- (di-n-propoxymethylsilyl) -2- (tri-n-propoxysilyl) ethane, 1- (di-iso -Propoxymethylsilyl) -2- (tri-iso-propoxysilyl) ethane, 1- (di-n-butoxymethylsilyl) -2- (tri-n-butoxysilyl) ethane, 1- (di-sec-butoxy) Methylsilyl) -2- (tri-sec-butoxysilyl) ethane, 1- (di-tert-butoxymethylsilyl) -2- (tri-tert-butoxysilyl) ethane,

  Bis (dimethoxymethylsilyl) methane, bis (diethoxymethylsilyl) methane, bis (di-n-propoxymethylsilyl) methane, bis (di-iso-propoxymethylsilyl) methane, bis (di-n-butoxymethylsilyl) ) Methane, bis (di-sec-butoxymethylsilyl) methane, bis (di-tert-butoxymethylsilyl) methane, 1,2-bis (dimethoxymethylsilyl) ethane, 1,2-bis (diethoxymethylsilyl) Ethane, 1,2-bis (di-n-propoxymethylsilyl) ethane, 1,2-bis (di-iso-propoxymethylsilyl) ethane, 1,2-bis (di-n-butoxymethylsilyl) ethane, 1,2-bis (di-sec-butoxymethylsilyl) ethane, 1,2-bis (di-tert-butoxymethyl) Silyl) ethane, 1,2-bis (trimethoxysilyl) benzene, 1,2-bis (triethoxysilyl) benzene, 1,2-bis (tri-n-propoxysilyl) benzene, 1,2-bis (tri -Iso-propoxysilyl) benzene, 1,2-bis (tri-n-butoxysilyl) benzene, 1,2-bis (tri-sec-butoxysilyl) benzene, 1,2-bis (tri-tert-butoxysilyl) ) Benzene, 1,3-bis (trimethoxysilyl) benzene, 1,3-bis (triethoxysilyl) benzene, 1,3-bis (tri-n-propoxysilyl) benzene, 1,3-bis (tri- iso-propoxysilyl) benzene, 1,3-bis (tri-n-butoxysilyl) benzene, 1,3-bis (tri-sec-butoxysilyl) benzene Zen, 1,3-bis (tri-tert-butoxysilyl) benzene, 1,4-bis (trimethoxysilyl) benzene, 1,4-bis (triethoxysilyl) benzene, 1,4-bis (tri-n) -Propoxysilyl) benzene, 1,4-bis (tri-iso-propoxysilyl) benzene, 1,4-bis (tri-n-butoxysilyl) benzene, 1,4-bis (tri-sec-butoxysilyl) benzene 1,4-bis (tri-tert-butoxysilyl) benzene and the like.

Among these, bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, 1,2-bis (trimethoxysilyl) ethane, 1,2-bis (triethoxysilyl) ethane, 1- (dimethoxymethyl) Silyl) -1- (trimethoxysilyl) methane, 1- (diethoxymethylsilyl) -1- (triethoxysilyl) methane, 1- (dimethoxymethylsilyl) -2- (trimethoxysilyl) ethane, 1- ( Diethoxymethylsilyl) -2- (triethoxysilyl) ethane, bis (dimethoxymethylsilyl) methane, bis (diethoxymethylsilyl) methane, 1,2-bis (dimethoxymethylsilyl) ethane, 1,2-bis ( Diethoxymethylsilyl) ethane, 1,2-bis (trimethoxysilyl) benzene, 1,2-bis (trie Xylsilyl) benzene, 1,3-bis (trimethoxysilyl) benzene, 1,3-bis (triethoxysilyl) benzene, 1,4-bis (trimethoxysilyl) benzene, 1,4-bis (triethoxysilyl) Benzene and the like are preferred.
In addition, these compounds represented by the general formula (3) may be used singly or in combination of two or more.

<Content ratio of structural unit derived from hydrolyzable silane compound>
The content ratio of the structural unit derived from the compound (1) in the polymer (A) is 30 to 100 mol% when the total of all the structural units contained in the polymer (A) is 100 mol%. More preferably, it is 60-100 mol%, More preferably, it is 70-100 mol%. A content ratio of 30 to 100 mol% is preferable because the balance between the process margin during the curing process and the film properties of the cured film is good.
Further, the content ratio of the structural unit derived from the compound (2) is preferably 0 to 70 mol% when the total of all the structural units contained in the polymer (A) is 100 mol%, More preferably, it is 0-40 mol%, More preferably, it is 0-30 mol%. A content ratio of 0 to 70 mol% is preferable because the balance between the process margin during the curing process and the physical properties of the cured film is good.
Furthermore, the total of the structural unit derived from the compound (1) and the structural unit derived from the compound (2) is 100 mol when the total of all the structural units contained in the polymer (A) is 100 mol%. % Or less, more preferably 30 to 100 mol%, still more preferably 60 to 100 mol%. The total content of 30 to 100 mol% is preferable because the effect of the structural unit derived from the compound (1) or the compound (2) in the polymer (A) for pattern formation can be obtained.
Further, the content ratio of the structural unit derived from the compound (3) is preferably 50% by mole or less when the total of all the structural units contained in the polymer (A) is 100% by mole, Preferably it is 0-40 mol%, More preferably, it is 0-30 mol%. When this content is 50 mol% or less, pattern formation is not significantly inhibited without the effect of the structural unit derived from the compound (1) or compound (2) in the polymer (A) on the pattern formation. Since the effect of the structural unit derived from the compound (3) with respect to can be obtained.

<Molecular weight of polymer (A)>
It is preferable that the polystyrene conversion weight average molecular weight (Mw) by the gel permeation chromatography (GPC) of the said polymer (A) is 1000-100000, More preferably, it is 1000-10000. When this Mw exceeds 100,000, gelation tends to occur. On the other hand, if it is less than 1000, problems are likely to occur in coating properties and storage stability.

<Method for preparing polymer (A)>
The polymer (A) can be obtained by hydrolytic condensation reaction using a hydrolyzable silane compound [the compounds (1) to (3)] as a starting material. Specifically, for example, it can be prepared by dissolving the starting material in an organic solvent, adding water intermittently or continuously to the solution, and causing a hydrolysis condensation reaction. At this time, the catalyst may be dissolved or dispersed in advance in an organic solvent, or may be dissolved or dispersed in the added water. Moreover, the temperature for performing a hydrolysis-condensation reaction is 0-100 degreeC normally.
In preparing the polymer (A), (1) a mixture of the compounds (1), (2) and (3) may be subjected to a hydrolytic condensation reaction, or (2) each compound is hydrolyzed. Hydrolysis condensation reaction or condensation reaction may be performed using at least one of the decomposition product and its condensate, or at least one of the hydrolyzate of the mixture of selected compounds and its condensate.

  Although it does not specifically limit as water for performing the said hydrolysis-condensation reaction, It is preferable to use ion-exchange water. Moreover, the said water is used in the quantity used as 0.25-3 mol with respect to 1 mol of alkoxyl groups of the hydrolysable silane compound used, Preferably it is 0.3-2.5 mol. 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 organic solvent is not particularly limited as long as it is an organic solvent used for this kind of application, and examples thereof include propylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monopropyl ether.

Examples of the catalyst include metal chelate compounds, organic acids, and inorganic acids.
Examples of the metal chelate compound include a titanium chelate compound, a zirconium chelate compound, and an aluminum chelate compound. Specifically, compounds described in JP 2000-356854 A can be used.
Examples of the organic acid include acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oxalic acid, maleic acid, methylmalonic acid, adipic acid, sebacic acid, Gallic acid, butyric acid, merit acid, arachidonic acid, mykimic acid, 2-ethylhexanoic acid, oleic acid, stearic acid, linoleic acid, linolenic acid, salicylic acid, benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, benzene Examples include sulfonic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, and tartaric acid.
Examples of the inorganic acid include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, and phosphoric acid.

Of these catalysts, metal chelate compounds, organic acids and inorganic acids are preferred. The said catalyst may be used independently and may be used in combination of 2 or more type.
Moreover, the said catalyst is 0.001-10 mass parts normally with respect to 100 mass parts of said hydrolysable silane compounds, Preferably it is used in 0.01-10 mass parts.

Moreover, after performing a hydrolysis condensation reaction, it is preferable to perform the removal process of reaction by-products, such as lower alcohols, such as methanol and ethanol, for example. Thereby, since the purity of the organic solvent is increased, it is possible to obtain a composition having excellent coating properties and excellent storage stability.
The method for removing the reaction by-product is not particularly limited as long as the reaction of the hydrolyzate and / or its condensate does not proceed. For example, the reaction by-product has a boiling point higher than that of the organic solvent. If it is low, it can be distilled off under reduced pressure.

  The polymer (A) in the present invention may be used after being isolated from the polymer solution, or may be used as it is. In addition, when using as a polymer solution, the solvent substituted by the below-mentioned solvent (C) may be used as needed.

[1-2] Radiation sensitive base generator (B)
The base generator (B) generates a base by exposure. When the resin contains an acidic component or a thermal acid generator (D) described later, the base generator (B) is acidic in the resin by the action of the base generated by exposure. The components are neutralized, the resin components are not insolubilized during baking after exposure, which will be described later, become readily soluble in an alkali developer, and have a function of forming a positive resist pattern.

  Examples of the base generator (B) include triphenylsulfonium compounds, triphenylmethanol; photoactive carbamates such as benzyl carbamate compounds and benzoin carbamate compounds; o-carbamoyl hydroxylamines, o-carbamoyl oximes; Examples thereof include tic sulfonamides, alpha-lactams, and amides such as N- (2-allylethynyl) amide; oxime esters, α-aminoacetophenone, cobalt complexes, and the like. Among these, at least one selected from benzyl carbamate compounds and o-carbamoylhydroxyamines is preferable.

  Specific examples of the base generator (B) include a photobase generator represented by the following general formula (4) (hereinafter, also referred to as “base generator (B1)”); 2-nitrobenzylcyclohexyl carbamate. , [[(2,6-dinitrobenzyl) oxy] carbonyl] cyclohexylamine, N- (2-nitrobenzyloxycarbonyl) pyrrolidine, bis [[(2-nitrobenzyl) oxy] carbonyl] hexane 1,6-diamine Selected carbamate photobase generator (hereinafter also referred to as “base generator (B2)”); triphenylmethanol, o-carbamoylhydroxylamide, o-carbamoyloxime, 4- (methylthiobenzoyl) -1-methyl -1-morpholinoethane, (4-morpholinobenzoyl) -1-benzyl-1-dimethylamino Propane, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) - butanone, hexaamminecobalt (III) tris (triphenylmethyl borate) and the like. Among these, the photobase generator (B1) and the photobase generator (B2) are preferable, and the photobase generator (B1) is particularly preferable.

〔一般式（４）において、Ｒ^８〜Ｒ^１０は、それぞれ独立して、アルキル基、アルコキシ基又はハロゲン原子を示し、ｎ^１〜ｎ^３は、それぞれ独立して、０〜３の整数である。〕

In [Formula ^{(4), R} 8 ~R ¹⁰ are each independently an alkyl group, an alkoxy group or a halogen ^atom, n 1 ~n ³ are each independently an integer of 0 to 3 . ]

The alkyl group of R ⁸ to R ¹⁰ in the general formula (4) is not particularly limited, it is preferably an alkyl group having 1 to 5 carbon atoms. The alkyl group is preferably linear or branched. In particular, a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group are preferable.
Although the alkoxy group of said R < ⁸ > -R < ¹⁰ > is not specifically limited, It is preferable that it is a C1-C5 alkoxy group. The alkoxy group is preferably linear or branched. In particular, a methoxy group and an ethoxy group are preferable.
Examples of the halogen atom for R ^{8 to} R ¹⁰ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among these, a fluorine atom is preferable.

Moreover, n < ¹ > -n < ³ > in General formula (4) is an integer of 0-3 each independently, Preferably it is 0 or 1. Note that n ^{1 to} n ³ may all be the same or different. In particular, the case where all of n ^{1 to} n ³ are 0 is most preferable.

  Here, as a suitable specific example of the said photobase generator (B1), the compound of following formula (4-1) can be mentioned. Moreover, 2-nitrobenzyl cyclohexyl carbamate is mentioned as a suitable specific example of the said photobase generator (B2).

The said base generator (B) may be used individually by 1 type, and may be used in combination of 2 or more type.
The content of the base generator (B) is appropriately adjusted depending on the pH of the positive radiation sensitive composition, the type of the radiation sensitive base generator and the exposure amount. That is, the exposed portion after PEB is adjusted as appropriate so that it becomes a neutral region of pH = 6-8. Usually, it is 1-10 mass parts with respect to 100 mass parts of polymers (A). When this content is 1 to 10 parts by mass, a positive radiation sensitive composition is obtained that is excellent in pattern shape, has no pattern deformation due to curing treatment, and can form a cured pattern having a sufficiently low relative dielectric constant. Therefore, it is preferable. Furthermore, the exposure margin (EL margin) increases, and the base generation efficiency by exposure increases, thereby improving the sensitivity.

[1-3] Solvent (C)
As the solvent (C), an organic solvent is preferably used. Usually, each component (the polymer (A), the base generator (B), an acid generator and an additive described below) is the organic solvent. Dissolved or dispersed in.
The organic solvent is selected from the group consisting of alcohol solvents, ketone solvents, amide solvents, ether solvents, ester solvents, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, and halogen-containing solvents. There is at least one kind.

Examples of the alcohol solvent include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, and 2-methyl. Butanol, sec-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2- Ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl al Lumpur, furfuryl alcohol, phenol, cyclohexanol, methyl cyclohexanol, 3,3,5-trimethyl cyclohexanol, benzyl alcohol, mono-alcohol solvents such as diacetone alcohol;
Ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2 Polyhydric alcohol solvents such as ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol;

Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl Ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol It may be mentioned monomethyl ether, dipropylene glycol monoethyl ether, polyhydric alcohol partial ether solvents such as dipropylene glycol monopropyl ether.
These alcohol solvents may be used alone or in combination of two or more.

  Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl- n-hexyl ketone, di-i-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, diacetone alcohol , Acetophenone, fenchon and the like. These ketone solvents may be used alone or in combination of two or more.

  Examples of the amide solvent include N, N-dimethylimidazolidinone, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide. And nitrogen-containing solvents such as N-methylpropionamide and N-methylpyrrolidone. These amide solvents may be used alone or in combination of two or more.

  Examples of the ether solvent include ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane, and dimethyl. Dioxane, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-n-hexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2 -Ethyl butyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, di Tylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol di-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytriglycol, tetraethylene glycol di-n-butyl ether, propylene glycol Monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, di Phenyl ether, anisole, and the like. These ether solvents may be used individually by 1 type, and may be used in combination of 2 or more type.

  Examples of the ester solvent include diethyl carbonate, propylene carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, Sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, Methyl acetoacetate, ethyl acetoacetate, ethylene acetate monomethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol acetate Mono-n-butyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, glycol diacetate Methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, Examples include diethyl malonate, dimethyl phthalate, and diethyl phthalate. These ester solvents may be used alone or in combination of two or more.

  Examples of the aliphatic hydrocarbon solvent include n-pentane, i-pentane, n-hexane, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane, n-octane, i -Octane, cyclohexane, methylcyclohexane and the like. These aliphatic hydrocarbon solvents may be used alone or in combination of two or more.

  Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propyl benzene, i-propyl benzene, diethyl benzene, i-butyl benzene, triethyl benzene, di-i-. Examples include propyl benzene, n-amyl naphthalene, and trimethyl benzene. These aromatic hydrocarbon solvents may be used alone or in combination of two or more.

  Examples of the halogen-containing solvent include dichloromethane, chloroform, chlorofluorocarbon, chlorobenzene, dichlorobenzene, and the like. These halogen-containing solvents may be used alone or in combination of two or more.

Among these solvents (C), it is preferable to use an organic solvent having a boiling point of less than 150 ° C. In particular, it is preferable to use one or more of alcohol solvents, ketone solvents and ester solvents.
These solvents (C) may be the same as those used for the synthesis of the polymer (A).

[1-4] Thermal acid generator (D)
The positive radiation-sensitive composition of the present invention may contain a thermal acid generator [hereinafter referred to as “thermal acid generator (D)”]. The thermal acid generator (D) generates an acid by heating, and by adding this component, an acid is generated during PEB, the curing of the polymer (A) is promoted, and a good contrast is obtained. be able to.
Examples of the thermal acid generator (D) include 2,4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, and alkyl esters of other organic sulfonic acids. .
Furthermore, sulfonium salts, iodonium salts, benzothiazonium salts, ammonium salts, onium salts such as phosphonium salts, and the like. Specifically, for example, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium Salts of fluoride metal compounds such as hexafluoroantimonate, 4-acetoxyphenylbenzylsulfonium hexafluoroantimonate, 3-benzylbenzothiazolium hexafluoroantimonate; compounds represented by the following formula (5-1) and Examples thereof include salts of organic sulfonic acids such as the compound represented by formula (5-2).

  Among these onium salts, an ammonium salt of an organic sulfonic acid is particularly preferable, and a compound represented by the following formula (5-3) is particularly preferable.

R ¹¹ in the general formula (5-3) is an alkyl group having 1 to 15 carbon atoms. The alkyl group preferably has 3 to 15 carbon atoms, more preferably 3 to 12 carbon atoms. The alkyl group may be linear or branched, but is more preferably linear. In particular, the alkyl group is preferably a dodecyl group.
Moreover, x in general formula (5-3) is an integer of 1-3, More preferably, it is 1. When x is 2 or 3, the plurality of R ¹¹ may be the same or different from each other.
The bonding position of R ^{11 in} the benzene ring is not particularly limited. However, in consideration of availability, it is preferable that the bonding position is at least in the para position with respect to the bonding position of —SO ₃ ^— .

R ^{12 to} R ¹⁴ in the general formula (5-3) are each independently an alkyl group having 1 to 10 carbon atoms. The alkyl group preferably has 1 to 5 carbon atoms. Moreover, this alkyl group may be linear or branched. In particular, the alkyl group is preferably a methyl group.
Moreover, R < ¹⁵ > in General formula (5-3) is a C1-C5 hydroxyalkyl group. This hydroxyalkyl group is preferably linear or branched. Among them, - _{(CH 2)} in m OH [wherein, m is an integer of 1 to 4. ] Is preferable, and —CH ₂ CH ₂ OH is particularly preferable.

The said thermal acid generator (D) may be used individually by 1 type, and may be used in combination of 2 or more type.
Moreover, it is preferable that content of this thermal acid generator (D) is 1-10 mass parts with respect to 100 mass parts of said polymers (A), More preferably, it is 1-8 mass parts, More preferably. Is 1-6 parts by mass. When this content is 1 to 6 parts by mass, a positive radiation sensitive composition is obtained that is excellent in pattern shape, has no pattern deformation due to curing treatment, and can form a cured pattern having a sufficiently low relative dielectric constant. Therefore, it is preferable.

[1-5] Additives The positive radiation sensitive composition of the present invention may contain additive components such as organic polymers and surfactants.

<Organic polymer>
Examples of the organic polymer include a polymer having a sugar chain structure, a vinylamide polymer, a (meth) acrylic polymer, an aromatic vinyl compound polymer, a dendrimer, polyimide, polyamic acid, polyarylene, polyamide, poly Examples include quinoxaline, polyoxadiazole, fluorine-based polymers, and polymers having a polyalkylene oxide structure.
Examples of the polymer having a polyalkylene oxide structure include a polymethylene oxide structure, a polyethylene oxide structure, a polypropylene oxide structure, a polytetramethylene oxide structure, and a polybutylene oxide structure. Specifically, polyoxymethylene alkyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, ethylene oxide derivative of alkylphenol formalin condensate, polyoxyethylene poly Oxypropylene block copolymer, ether type compounds such as polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene fatty acid alkanolamide sulfate, etc. Ether ester type compound, polyethylene glycol fatty acid ester, ethylene glycol fatty acid Ester, fatty acid monoglycerides, polyglycerol fatty acid esters, sorbitan fatty acid esters, propylene glycol fatty acid esters, ether-ester type compounds such as sucrose fatty acid esters.

Examples of the polyoxyethylene polyoxypropylene block copolymer include compounds having the following block structure.
− (X ′) ₁ − (Y ′) _m −
− (X ′) ₁ − (Y ′) _m − (X ′) _n −
[Wherein, X ′ represents a group represented by —CH ₂ CH ₂ O—, Y ′ represents a group represented by —CH ₂ CH (CH ₃ ) O—, and l represents 1 to 90, m Represents a number from 10 to 99, and n represents a number from 0 to 90. ]

Among these organic polymers, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol Ether type compounds such as fatty acid esters are preferred.
In addition, these organic polymers may be used individually by 1 type, and may be used in combination of 2 or more type.

<Surfactant>
The surfactant is a component having an effect of improving coating properties, striation, developability, etc., for example, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, Examples include silicone surfactants, polyalkylene oxide surfactants, fluorine surfactants, poly (meth) acrylate surfactants, and the like. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate In addition to nonionic surfactants such as SH8400 FLUID (Toray Dow Corning Silicone Co.), KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (above, manufactured by Kyoeisha Chemical Co., Ltd.), F-top EF301, EF303, EF352 (above, manufactured by Tochem Products Co., Ltd.), Megafax F171, F173 (above, Dainippon Ink & Chemicals, Inc.) Manufactured), FLORARD FC430, FC431 (above, manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC -105, SC-106 (above, manufactured by Asahi Glass Co., Ltd.) and the like. Of these, fluorine-based surfactants and silicone-based surfactants are preferable.
In addition, these may be used individually by 1 type and may be used in combination of 2 or more type.

  Moreover, the said surfactant is normally used in 0.00001-1 mass part with respect to 100 mass parts of said polymers (A).

[1-6] pH of positive radiation sensitive composition
Although it will not be limited if the pH of the positive radiation sensitive composition of this invention is acidic, Usually, it is 1-4, More preferably, it is 3-4. When this pH is less than 1, deterioration of storage stability and resolution may occur. On the other hand, when the pH exceeds 4, the exposure margin (EL margin) may be insufficient.
This pH is a value measured as follows.
<Measurement method of pH>
4.5 g of methanol / ion exchange water mixed solvent [3/1 (w / w)], polymer solution [polymer solid concentration: 30% by mass, solvent: propylene glycol monomethyl ether acetate], As a measurement sample, the pH was measured with a pH meter (model number “S20”, manufactured by METTLER TOLEDO).

[2] Preparation of positive-type radiation-sensitive composition The positive-type radiation-sensitive composition of the present invention comprises the polymer (A), the base generator (B), the solvent (C), and as necessary. It is obtained by mixing the thermal acid generator (D) and the other additives. In addition, a polymer (A) may be used individually by 1 type, and may be used in combination of 2 or more type.
Moreover, although the solid content density | concentration of positive type radiation composition is suitably adjusted according to a use purpose, it can be 1-50 mass%, for example, can be 5-40 mass% especially. When this solid content concentration is 1 to 50% by mass, the film thickness of the coating film is in an appropriate range.

[3] Cured Pattern Forming Method The cured pattern forming method of the present invention is (1) a step of applying a positive radiation sensitive composition to a substrate and forming a film [hereinafter referred to as “step (1)”. And (2) a step of baking the obtained film [hereinafter referred to as “step (2)”]. And (3) a step of exposing the baked film [hereinafter referred to as “step (3)”]. And (4) a step of baking the exposed film [hereinafter referred to as “step (4)”]. And (5) a step of developing the baked film with a developer to form a positive pattern [hereinafter referred to as “step (5)”]. And (6) a step of forming the cured pattern by subjecting the obtained positive pattern to at least one curing treatment of high energy ray irradiation and heating [hereinafter referred to as “step (6)”]. ].

In the step (1), a positive radiation sensitive composition is applied to the substrate to form a film. In addition, about a positive radiation sensitive composition, the above-mentioned description is applicable as it is.
Examples of the method of applying the positive radiation sensitive composition include spin coating, cast coating, roll coating, and the like. At this time, the obtained film is applied so as to have a predetermined film thickness.
Examples of the substrate include a wafer coated with a Si-containing layer such as Si, SiO ₂ , SiN, SiC, SiCN, or SiON. In order to maximize the potential of the positive radiation sensitive composition, it is used, for example, as disclosed in Japanese Patent Publication No. 6-12452 (Japanese Patent Application Laid-Open No. 59-93448). An organic or inorganic antireflection film can also be formed on the substrate.

In the step (2), the coating film is baked (hereinafter referred to as “PB”), and the solvent in the coating film is volatilized.
The heating conditions for this PB are appropriately selected depending on the composition of the composition, but are usually 60 to 150 ° C, preferably 70 to 120 ° C.

In the step (3), a predetermined region of the baked film is exposed so as to obtain a predetermined positive pattern.
The radiation used for this exposure is appropriately selected from charged particle beams such as visible light, ultraviolet light, far ultraviolet light, X-rays, and electron beams, depending on the type of acid generator used. Far ultraviolet rays and electron beams represented by ArF excimer laser (wavelength 193 nm) or KrF excimer laser (wavelength 248 nm) are preferable.
Moreover, exposure conditions, such as exposure amount, are suitably selected according to the compounding composition of a radiation sensitive composition, the kind of additive, etc.

  In the step (4), a baking process (PEB) is performed after the exposure. By this PEB, acid / base neutralization reaction in the coating film and insolubilization of the polymer in the unexposed area proceed. The heating conditions for this PEB are appropriately selected depending on the composition of the composition, but are usually 30 to 200 ° C, preferably 50 to 170 ° C.

In the step (5), a predetermined positive pattern is formed by developing the film baked after exposure.
Examples of the developer used for this 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. Of these, tetramethylammonium hydroxide is particularly preferable.

Moreover, an organic solvent can also be used as a developing solution used for this development. Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone, methyl i-butyl ketone, cyclopentanone, cyclohexanone, 3-methylcyclopentanone, and 2,6-dimethylcyclohexanone; methyl alcohol, ethyl alcohol, and n-propyl. Alcohols such as alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, 1,4-hexanedimethylol; ethers such as tetrahydrofuran and dioxane Esters such as ethyl acetate, n-butyl acetate and i-amyl acetate; aromatic hydrocarbons such as toluene and xylene; phenol, acetonylacetone and dimethylformamide. In addition, these organic solvents may be used individually by 1 type, and may be used in combination of 2 or more type.
An appropriate amount of a surfactant or the like can be added to these developers.
In addition, after developing with a developing solution, generally it wash | cleans with water and dries.

In the step (6), the obtained positive pattern is cured to form a cured pattern.
Examples of the curing treatment method include heat treatment, irradiation with high energy rays such as electron beams and ultraviolet rays, plasma treatment, and the like. Among these, at least one of heat treatment and high energy ray irradiation treatment is preferable. These treatments can be used in combination.
When curing is performed by heat treatment, the positive pattern is preferably heated at 80 to 450 ° C. in an inert atmosphere or under reduced pressure, more preferably 300 to 450 ° C. As a heating method at this time, a hot plate, an oven, a furnace, or the like can be used.
Further, in order to control the curing rate of the positive type pattern, it is possible to heat stepwise or select an atmosphere such as nitrogen, air, oxygen, reduced pressure or the like as necessary. Through such a process, a silica-based film (cured pattern) having a low relative dielectric constant can be produced.
By performing the curing treatment, substituents and molecules having large orientation polarization are reduced, and the proportion of pores in the film is increased, so that the relative dielectric constant of the film can be lowered.

[4] Relative permittivity of cured pattern The relative permittivity of the cured pattern obtained using the positive radiation-sensitive composition of the present invention is preferably 1.5 to 3, more preferably 2 to 3. It is. When this relative dielectric constant is 1.5 to 3, it can be suitably used as a low relative dielectric constant material. Therefore, this cured pattern can be used not only as a material for microfabrication of semiconductor elements such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM, but also as an interlayer insulating film material. Useful for semiconductor devices including damascene processes.
The relative dielectric constant can be adjusted by changing the resin composition and curing treatment conditions.

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Here, “part” and “%” are based on mass unless otherwise specified.

[1] Production of polymer solution As shown in the following synthesis examples (synthesis examples 1 to 3), resin solution No. 1-3 polymer solutions were prepared.
In addition, the measurement of the weight average molecular weight (Mw) of the polymer obtained by each synthesis example was performed by the following method.

<Measurement of weight average molecular weight (Mw)>
The weight average molecular weight (Mw) of the polymer obtained in each of the following synthesis examples was measured by a size exclusion chromatography (SEC) method under the following conditions.
Sample: A 2-methoxyethanol solution of LiBr—H ₃ PO _{4 at} a concentration of 10 mmol / L was used as a solvent, and 0.1 g of a hydrolysis condensate was added to 100 cc of 10 mmol / L LiBr—H ₃ PO _{4 in} a 2-methoxyethanol solution. And dissolved.
Standard sample: Polyethylene oxide manufactured by WAKO was used.
Apparatus: A high-speed GPC apparatus (model HLC-8120GPC) manufactured by Tosoh Corporation was used.
Column: Tosoh Co., Ltd. product, TSK-GEL SUPER AWM-H (15 cm in length) was installed in series and used.
Measurement temperature: 40 ° C
Flow rate: 0.6 ml / min.
Detector: Detected by RI of a built-in high-speed GPC device (model HLC-8120GPC) manufactured by Tosoh Corporation.

<Synthesis Example 1> (Resin Solution No. 1)
In a nitrogen-substituted quartz three-necked flask, 1.39 g of a 20% maleic acid aqueous solution and 90.99 g of ultrapure water were added and heated to 75 ° C. Next, a solution prepared by mixing 116.1 g (0.852 mol) of methyltrimethoxysilane, 32.4 g (0.213 mol) of tetramethoxysilane, and 9.10 g of ethoxypropanol was dropped into the reaction vessel over 1 hour, Stir at 75 ° C. for 2 hours. Then, this reaction liquid was returned to room temperature and concentrated under reduced pressure until the solid content concentration became 25%, to obtain 270 g of a polymer solution. The polymer in the polymer solution is referred to as polymer (A-1) [see the following formula (A-1) for the structural unit].
In addition, Mw of the polymer (A-1) was 8800.

<Synthesis Example 2> (Resin Solution No. 2)
In a nitrogen-substituted quartz three-necked flask, 1.33 g of 20% maleic acid aqueous solution and 87.22 g of ultrapure water were added and heated to 60 ° C. Then, a solution prepared by mixing 129.2 g (0.948 mol) of methyltrimethoxysilane, 16.0 g (0.105 mol) of tetramethoxysilane, and 16.2 g of ethoxypropanol was dropped into the reaction vessel over 1 hour. Stir at 60 ° C. for 2 hours. Then, this reaction liquid was returned to room temperature and concentrated under reduced pressure until the solid content concentration became 25%, to obtain 270 g of a polymer solution. The polymer in this polymer solution is referred to as polymer (A-2) [for the structural unit, refer to the following formula (A-2)].
In addition, Mw of the polymer (A-2) was 4800.

<Synthesis Example 3> (Polymer Solution No. 3)
In a nitrogen-substituted quartz three-necked flask, 1.33 g of 20% maleic acid aqueous solution and 87.22 g of ultrapure water were added and heated to 60 ° C. Next, a solution in which 129.2 g (0.948 mol) of octyltrimethoxysilane and 16.2 g of ethoxypropanol were mixed was dropped into the reaction vessel over 1 hour, and stirred at 60 ° C. for 2 hours. Then, this reaction liquid was returned to room temperature and concentrated under reduced pressure until the solid content concentration became 25%, to obtain 270 g of a polymer solution. The polymer in this polymer solution is referred to as polymer (A-3) [for the structural unit, refer to the following formula (A-3)].
In addition, Mw of the said silicon containing resin (A-3) was 1100.

[2] Preparation of positive-type radiation-sensitive composition (Compositions 1 to 6)
In the ratio shown in Table 1, (A) a polymer solution (solid content: 25%), (B) a base generator, (D) a thermal acid generator, and (E) a surfactant are mixed, Positive type radiation sensitive compositions (Compositions 1 to 6) were prepared. Further, propylene glycol monomethyl ether acetate was added to these compositions so that the solid content concentration was 17%.

Moreover, pH of each composition was measured as follows, and the value was written together in Table 1.
<Measurement method of pH>
4.5 g of methanol / ion exchange water mixed solvent [3/1 (w / w)], polymer solution [polymer solid concentration: 30% by mass, solvent: propylene glycol monomethyl ether acetate], Was used as a measurement sample, and the pH was measured with a pH meter (model number “S20”, manufactured by METTLER TOLEDO).

The details of (B) base generator, (D) thermal acid generator, and (E) surfactant in Table 1 are as follows.
<(B) Base generator>
B-1: 2-Nitrobenzylcyclohexyl carbamate B-2: o-carbamoylhydroxylamine
<(D) Thermal acid generator>
D-1: 4-Acetoxyphenyldimethylsulfonium hexafluoroarsenate D-2: Benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate
<(E) Surfactant>
E-1: SH8400 FLUID (Toray Dow Corning Silicon Co.)

[3] Evaluation of positive radiation sensitive composition The following various evaluations were performed using the compositions shown in Table 1. These evaluation results are shown in Table 2.
(1) Sensitivity (1-1) KrF exposure (Examples 1-4 and Comparative Examples 1-2)
As a substrate, an 8-inch silicon wafer having a lower layer antireflection film (“DUV42-6”, manufactured by Nissan Chemical Industries, Ltd.) having a film thickness of 60 nm formed on the surface was used. For the formation of the antireflection film, “CLEAN TRACK ACT8” (manufactured by Tokyo Electron Limited) was used.
Next, the radiation-sensitive compositions (Compositions 1 to 6) shown in Table 1 were spin-coated on the substrate by the CLEAN TRACK ACT8, and baked (PB) under the conditions shown in Table 2 to obtain a film thickness. A 600 nm film was formed. This film was exposed through a mask pattern with a KrF excimer laser exposure apparatus (“NSR S203B”, manufactured by NIKON) under the conditions of NA = 0.68 and σ = 0.75-1 / 2 annular illumination. Thereafter, PEB was performed under the conditions shown in Table 2, and then developed with a 2.38 mass% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 60 seconds, washed with water, and dried to form a positive pattern. . At this time, the exposure amount for forming a line-and-space pattern (1L1S) having a line width of 250 nm in a one-to-one line width was defined as the optimum exposure amount, and this optimum exposure amount was defined as the sensitivity. A scanning electron microscope (“S-9380”, manufactured by Hitachi High-Technologies Corporation) was used for measuring the line width.

(1-2) g-line, h-line, i-line exposure (Examples 5 to 7)
A radiation-sensitive composition (Composition 1) was spin-coated on an 8-inch silicon wafer with the CLEAN TRACK ACT8, and prebaked on a hot plate at 90 ° C. for 2 minutes to form a film having a thickness of 700 nm. (In addition, the obtained coating film was a smooth coating film with no defects such as cracks). A NSR1755i7A reduction projection exposure machine manufactured by Nikon Corporation [NA = 0.50, λ = 365 nm (i-line), 405 nm (through a pattern mask having 4.0 μm □ dot / 2.0 μm space pattern) h line), 436 nm (g line)]. Then, after heating at 70 degreeC for 1 minute, it developed with 23.degree. C. for 60 seconds with a 2.38 mass% tetramethylammonium hydroxide aqueous solution, washed with water, and dried to form a positive pattern. At this time, the exposure amount for forming a line-and-space pattern (1L1S) having a line width of 350 nm in a one-to-one line width was defined as the optimum exposure amount, and this optimum exposure amount was defined as the sensitivity.

(2) Cross-sectional shape of pattern (2-1) Examples 1-4 and Comparative Examples 1-2
The cross-sectional shape of a line and space pattern (1L1S) having a line width of 250 nm formed in the same manner as in (1-1) was observed. At this time, in the cross-sectional shape shown in FIG. 1, the case of (b), (c) or (d) was “good”, and the case of (a), (e) or (f) was “bad”.
For observation of the cross-sectional shape, “S-4800” manufactured by Hitachi High-Technologies Corporation was used.

(2-2) Examples 5 to 7
The cross-sectional shape of a line and space pattern (1L1S) having a line width of 350 nm formed in the same manner as (1-2) was observed. At this time, in the cross-sectional shape shown in FIG. 1, the case of (b), (c) or (d) was “good”, and the case of (a), (e) or (f) was “bad”.
For observation of the cross-sectional shape, “S-4800” manufactured by Hitachi High-Technologies Corporation was used.

(3) Pattern deformation (3-1) Examples 1-4 and Comparative Examples 1-2
In order to evaluate the heat resistance of a line-and-space pattern (1L1S) having a line width of 250 nm formed in the same manner as in (1-1) above, a UV cure apparatus (“RapidCure FC”, manufactured by Axcelis) was used. Curing treatment was performed for 2 minutes under the conditions of ° C. and nitrogen atmosphere, and pattern deformation before and after the treatment was evaluated. At this time, the case where the pattern shape changed before and after UV curing was set as “Yes”, and the case where the pattern shape did not change was set as “None”.

(3-2) Examples 5 to 7
In order to evaluate the heat resistance of a line-and-space pattern (1L1S) having a line width of 350 nm formed in the same manner as in the above (1-2), a UV cure apparatus (“RapidCure FC”, manufactured by Axcelis) was used. Curing treatment was performed for 2 minutes under the conditions of ° C. and nitrogen atmosphere, and pattern deformation before and after the treatment was evaluated. At this time, the case where the pattern shape changed before and after UV curing was set as “Yes”, and the case where the pattern shape did not change was set as “None”.

(4) Relative permittivity measurement (4-1) Examples 1-7 and Comparative Examples 1-2
As the substrate, an 8-inch N-type silicon wafer having a resistivity of 0.1 Ω · cm or less was used. Subsequently, each radiation-sensitive composition (Compositions 1 to 6) in Table 1 was spin-coated on the substrate by CLEAN TRACK ACT8, and baked (PB) at 100 ° C. for 1 minute to obtain a film thickness. A 600 nm film was formed. The entire surface of the wafer was exposed to this coating without using a mask with a KrF excimer laser immersion exposure apparatus (“NSR S203B”, manufactured by NIKON) under the conditions of NA = 0.68 and σ = 0.75. Then, after heating at 100 degreeC for 1 minute, it developed with 23.degree. C. for 60 seconds with 2.38 mass% tetramethylammonium hydroxide aqueous solution, washed with water, and dried. Subsequently, it heated at 420 degreeC under nitrogen atmosphere for 30 minutes, and the cured film was obtained.
An aluminum electrode pattern was formed on the obtained film by a vapor deposition method, and a sample for measuring relative permittivity was prepared. With respect to the sample, the relative dielectric constant of the film at room temperature (24 ° C.) and 200 ° C. was measured by the CV method using “HP16451B electrode” and “HP4284A precision LCR meter” manufactured by Agilent, Inc. at a frequency of 100 kHz. .

As is clear from Table 2, the results of these examples confirmed that the positive radiation-sensitive composition in the present invention has a sufficient pattern forming ability. Moreover, the relative dielectric constant of the cured film (cured pattern) formed by forming the positive radiation-sensitive composition in the present invention and curing it by heating at 420 ° C. is 2.8 or less. Was confirmed.
Accordingly, the positive radiation-sensitive composition of the present invention itself has a radiation-sensitive property and can be patterned, and at the same time has a low dielectric constant when subjected to a curing treatment. It is suitable as an interlayer insulating film.

It is explanatory drawing which shows the cross-sectional shape of a pattern typically.

Claims (9)

(A) Hydrolytic condensation of at least one hydrolyzable silane compound selected from the hydrolyzable silane compound represented by the following general formula (1) and the hydrolyzable silane compound represented by the following general formula (2) A polymer obtained by
(B) a radiation sensitive base generator;
(C) a positive radiation-sensitive composition containing a solvent,
A positive radiation-sensitive composition characterized in that the pH is acidic.

[In General Formula (1), R represents a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 5 carbon atoms, a cyano group, a cyanoalkyl group, or an alkylcarbonyloxy group, and R ¹ represents Represents a monovalent organic group, and a represents an integer of 1 to 3; ]

[In General Formula (2), R ² represents a monovalent organic group. ]   The positive radiation-sensitive composition according to claim 1, which has a pH of 1 to 4.   The positive radiation sensitive composition according to claim 1 or 2, further comprising (D) a thermal acid generator.   The positive radiation sensitive composition according to any one of claims 1 to 3, wherein the radiation sensitive base generator (B) is at least one selected from benzyl carbamate compounds and o-carbamoylhydroxyamines. .   The positive radiation sensitive composition according to any one of claims 1 to 4, wherein the (A) polymer has a polystyrene-reduced weight average molecular weight of 1,000 to 10,000 by gel permeation column chromatography.   The content of the (B) radiation sensitive base generator is 1 to 10 parts by mass when the polymer (A) is 100 parts by mass. Positive radiation sensitive composition. (1) A step of applying a positive radiation-sensitive composition according to any one of claims 1 to 6 to a substrate to form a film;
(2) a step of baking the obtained film;
(3) exposing the baked coating;
(4) baking the exposed coating;
(5) developing the obtained film with a developer to form a positive pattern;
(6) A cured pattern forming method comprising: subjecting the obtained positive pattern to a curing process of at least one of high energy ray irradiation and heating to form a cured pattern.   A cured pattern obtained by the cured pattern forming method according to claim 7.   The cured pattern according to claim 8, wherein the relative dielectric constant is 1.5 to 3.

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