JP2005213491A - Film-forming composition, silica-based film, and method for forming silica-based film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film-forming composition capable of forming an interlayer insulation film having a low dielectric constant and excellent in mechanical strength, such as a modulus of elasticity. <P>SOLUTION: This film-forming composition contains a hydrolyzed condensate formed by subjecting (A) a silane compound expressed by general formula (1): Si(OR)<SB>4</SB>(R is a monovalent organic radical), (B) at least one kind of silane compound selected from a group comprising a silane compound expressed by general formula (2): R<SP>1</SP>Si(OR<SP>2</SP>)<SB>3</SB>(R<SP>1</SP>is H, F or a monovalent organic radical; and R<SP>2</SP>is a monovalent organic radical) and a silane compound expressed by general formula (3): R<SP>3</SP><SB>2</SB>Si(OR<SP>4</SP>)<SB>2</SB>(R<SP>3</SP>is H, F or a monovalent organic radical; and R<SP>4</SP>is a monovalent organic radical), and (C) a silane compound expressed by general formula (4): R<SP>5</SP><SB>3</SB>SiOR<SP>6</SP>(R<SP>5</SP>is H, F or a monovalent organic radical; and R<SP>6</SP>is H or a monovalent organic radical) to hydrolytic condensation in the presence of (D) a basic compound. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a film-forming composition, a silica-based film, and a method for forming a silica-based film, and more particularly, as a material for an interlayer insulating film used in a semiconductor element or the like, having excellent relative dielectric constant characteristics and mechanical strength. The present invention relates to a film-forming composition capable of forming a silica-based film, a silica-based film, and a method for forming a silica-based film.

Conventionally, a silica (SiO ₂ ) film formed by a vacuum process such as a CVD method is often used as an interlayer insulating film in a semiconductor element or the like. In recent years, for the purpose of forming a more uniform interlayer insulating film, a coating type insulating film called a SOG (Spin on Glass) film containing a hydrolysis product of tetraalkoxylane as a main component has been used. It has become. In addition, with high integration of semiconductor elements and the like, an interlayer insulating film having a low relative dielectric constant, which is mainly composed of polyorganosiloxane called organic SOG, has been developed.

  In order to avoid damages in semiconductor manufacturing processes such as CMP (Chemical Mechanical Planarization), in particular, with further higher integration and multi-layering of semiconductor elements and the like, a lower dielectric constant interlayer insulating film is required. There is a demand for an interlayer insulating film material having excellent mechanical properties such as elastic modulus.

  As a material having a low dielectric constant, a composition comprising a mixture of fine particles obtained by condensing alkoxysilane in the presence of ammonia and a basic partial hydrolyzate of alkoxysilane (see Patent Documents 1 and 2), A coating solution obtained by condensing a basic hydrolyzate of polyalkoxysilane in the presence of ammonia has been proposed (see Patent Documents 3 and 4). The material obtained by these methods is a reaction product. Because the properties of the product are not stable, and there are large variations in film properties such as the dielectric constant characteristics after PCT (Pressure Cooker Test), CMP resistance after PCT, and adhesion to the substrate after PCT, It was unsuitable.

  Patent Document 5 discloses that, in the hydrolysis condensation, alkoxysilane is continuously or intermittently added to a mixture of an organic solvent, a basic compound, and water, so that the dielectric constant characteristics after film formation and degassing after PCT are achieved. Disclosed is a film-forming composition having excellent characteristics and CMP resistance.

Patent Document 6 discloses that the temperature dependence of the dielectric constant of the coating film is small by performing alkoxysilane hydrolysis and / or condensation in the presence of a nitrogen onium salt compound, an alcohol having a boiling point of 100 ° C. or less, and water. Disclosed is a film-forming composition that has little subsequent change in dielectric constant and excellent mechanical strength of a coating film.
JP-A-5-263045 JP-A-5-315319 Japanese Patent Laid-Open No. 11-340219 JP 11-340220 A JP 2001-354905 A Japanese Patent Laid-Open No. 2002-20687

  However, with further high integration and multi-layering of semiconductor devices in recent years, further improvement in CMP resistance and the like is desired for interlayer insulating films and the like.

  An object of the present invention is to provide a film-forming composition that is further excellent in mechanical strength such as an elastic modulus of a coating film, and that can obtain a film that is suitably used as an interlayer insulating film.

  Another object of the present invention is to provide a method for producing the above-mentioned film forming composition.

  Another object of the present invention is to provide a method for forming a silica-based film using the above-mentioned film forming composition.

  Another object of the present invention is to provide a silica-based film that is obtained by the above-described film forming method and can be suitably used as an interlayer insulating film.

  The film forming composition according to the present invention comprises (A) a silane compound represented by the following general formula (1), (B) a silane compound represented by the following general formula (2), and the following general formula (3). At least one silane compound selected from the group of compounds represented by (C) and (C) a silane compound represented by the following general formula (4) was hydrolytically condensed in the presence of (D) a basic compound. Contains hydrolysis condensate.

Si (OR) ₄ (1)
(In the formula, R represents a monovalent organic group.)
R ¹ Si (OR ² ) ₃ (2)
(In the formula, R ¹ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ² represents a monovalent organic group.)
R ³ ₂ Si (OR ⁴ ) ₂ (3)
(In the formula, R ³ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ⁴ represents a monovalent organic group.)
R ⁵ ₃ SiOR ⁶ (4)
(Wherein R ⁵ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ⁶ represents a hydrogen atom or a monovalent organic group.)
The film-forming composition according to the present invention comprises (A) component, (B) component, and (C) component in 100 parts by weight of the total hydrolysis condensate, and (C) component is 1 to 79 parts by weight. Can be.

  The film-forming composition according to the present invention is a total of (B) component and (C) component among 100 parts by weight of the total hydrolysis condensate of component (A), component (B) and component (C). The amount can be 10 to 80 parts by weight.

  In the film forming composition according to the present invention, the concentrations of the component (A), the component (B) and the component (C) at the time of hydrolysis condensation are 0.1 to 10% by weight (in terms of complete hydrolysis condensate). Can be.

  In the film-forming composition according to the present invention, the amount of the component (D) used is 0.00001 to 1 mol with respect to 1 mol of the total amount of the components (A), (B) and (C). it can.

  The film forming composition according to the present invention can be obtained by hydrolyzing the component (A), the component (B) and the component (C) in the presence of water and an alcohol having a boiling point of 100 ° C. or lower.

  In the film-forming composition according to the present invention, the amount of water used may be 0.5 to 150 mol with respect to 1 mol of the total amount of the components (A), (B) and (C).

  In the film-forming composition according to the present invention, the reaction temperature during hydrolysis condensation may be 0 ° C to 100 ° C.

  The film forming composition according to the present invention may contain a solvent represented by the following general formula (5).

R ⁷ O (CHCH ₃ CH ₂ O) _e R ⁸ (5)
(R ⁷ and R ⁸ each independently represents a monovalent organic group selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or CH ₃ CO—, and e represents an integer of 1 to 2)
The method for forming a silica-based film according to the present invention includes applying the film-forming composition according to the present invention to a substrate and heating.

  The silica-based film according to the present invention is obtained by the method for forming a silica-based film according to the present invention.

  Hereinafter, the film forming composition, the insulating film forming method, and the details of the insulating film according to the present invention will be described.

1. Film-forming composition The film-forming composition according to the present invention is a hydrolysis-condensation product obtained by hydrolytic condensation of component (A), component (B), and component (C) in the presence of component (D). including. Each of the components (A), (B), (C), and (D) will be described below.

1.1 (A) Component The (A) silane compound used in the present invention is at least one silane compound (hereinafter referred to as “compound 1”) represented by the following general formula (1).

Si (OR) ₄ (1)
(In the formula, R represents a monovalent organic group.)
In the general formula (1), examples of the monovalent organic group represented by R include an alkyl group, an aryl group, an allyl group, and a glycidyl group. Especially, in General formula (1), it is preferable that R is a monovalent organic group, especially an alkyl group or an aryl group. Here, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, and preferably 1 to 5 carbon atoms. These alkyl groups may be linear or branched, Further, a hydrogen atom may be substituted with a fluorine atom or the like. In the general formula (1), 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.

  Specific examples of compound 1 include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane, tetraphenoxy. Silane and the like can be mentioned, and particularly preferred compounds include tetramethoxysilane and tetraethoxysilane. These may be used alone or in combination of two or more.

1.2 Component (B) The component (B) used in the present invention is at least one silane compound selected from the group of compounds represented by the following general formulas (2) and (3) (hereinafter “Compound 2”). And “compound 3”).

R ¹ Si (OR ² ) ₃ (2)
(In the formula, R ¹ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ² represents a monovalent organic group.)
R ³ ₂ Si (OR ⁴ ) ₂ (3)
(In the formula, R ³ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ⁴ represents a monovalent organic group.)
In the general formula (2), examples of the monovalent organic group represented by R ¹ and R ² include the same organic groups as those shown in the general formula (1).

  Specific examples of compound 2 include methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane, methyltri-sec-butoxysilane, methyltri-tert-butoxy. Silane, methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltriisopropoxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, ethyltri-tert-butoxysilane , Ethyltriphenoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxysilane, n-propyltriisopropoxy N-propyltri-n-butoxysilane, n-propyltri-sec-butoxysilane, n-propyltri-tert-butoxysilane, n-propyltriphenoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, isopropyl Tri-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-butoxysilane, n-butyltri-sec-butoxy Run, n-butyltri-tert-butoxysilane, n-butyltriphenoxysilane, 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- Butyltri-n-propoxysilane, tert-butyltriisopropoxysilane, tert-butyltri-n-butoxysilane, tert-butyltri-sec-butoxysilane, tert-butyltri -Tert-butoxysilane, tert-butyltriphenoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltriisopropoxysilane, phenyltri-n-butoxysilane, phenyltri-sec- Examples include butoxysilane, phenyltri-tert-butoxysilane, and phenyltriphenoxysilane. These may be used alone or in combination of two or more.

  Particularly preferred compounds as compound 2 are methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane. , Phenyltrimethoxysilane, phenyltriethoxysilane and the like.

In the general formula (3), examples of the monovalent organic group represented by R ³ and R ⁴ include the same organic groups as those shown in the general formula (1).

  Specific examples of the compound 3 include dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldi-n-propoxysilane, dimethyldiisopropoxysilane, dimethyldi-n-butoxysilane, dimethyldi-sec-butoxysilane, and dimethyldi-tert-butoxysilane. , Dimethyldiphenoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldi-n-propoxysilane, diethyldiisopropoxysilane, diethyldi-n-butoxysilane, diethyldi-sec-butoxysilane, diethyldi-tert-butoxysilane, diethyl Diphenoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-n-propyldi-n-propoxysilane, di-n-propyldiisopro Xysilane, di-n-propyldi-n-butoxysilane, di-n-propyldi-sec-butoxysilane, di-n-propyldi-tert-butoxysilane, di-n-propyldi-phenoxysilane, diisopropyldimethoxysilane, diisopropyldi Ethoxysilane, diisopropyldi-n-propoxysilane, diisopropyldiisopropoxysilane, diisopropyldi-n-butoxysilane, diisopropyldi-sec-butoxysilane, diisopropyldi-tert-butoxysilane, diisopropyldiphenoxysilane, 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-butyldiethoxysilane, 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-butyldiisopropoxysilane, di-tert-butyldi -N-butoxysilane, di-te rt-butyldi-sec-butoxysilane, di-tert-butyldi-tert-butoxysilane, di-tert-butyldi-phenoxysilane, diphenyldimethoxysilane, diphenyldi-ethoxysilane, diphenyldi-n-propoxysilane, diphenyldiiso Propoxysilane, diphenyldi-n-butoxysilane, diphenyldi-sec-butoxysilane, diphenyldi-tert-butoxysilane, diphenyldiphenoxysilane, divinyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltri Ethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-trifluoropropyltrimethoxysilane, γ-trifluoropropyltrieth Shishiran and the like. These may be used alone or in combination of two or more.

  Particularly preferred compounds as Compound 3 are dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, tetramethoxysilane, tetramethoxysilane, tetraethoxysilane, and tetra-n. -Propoxysilane, tetra-iso-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane, tetraphenoxysilane and the like.

1.3 (C) Component The (C) silane compound used in the present invention is at least one silane compound (hereinafter referred to as “compound 4”) represented by the following general formula (4).

R ⁵ ₃ SiOR ⁶ (4)
(In the formula, R ⁵ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ⁶ represents a hydrogen atom or a monovalent organic group.)
In the general formula (4), examples of the monovalent organic group represented by R ^{5 to} R ⁶ include the same organic groups as those shown in the general formula (1).

  Specific examples of the compound 4 include trimethylmethoxysilane, trimethylethoxysilane, trimethyl n-propoxysilane, trimethylisopropoxysilane, trimethyl n-butoxysilane, trimethyl sec-butoxysilane, trimethyl tert-butoxysilane, trimethylphenoxysilane, and triethyl. Methoxysilane, triethylethoxysilane, triethyl n-propoxysilane, triethylisopropoxysilane, triethyl n-butoxysilane, triethyl sec-butoxysilane, triethyl tert-butoxysilane, triethylphenoxysilane, tri-n-propylmethoxysilane, tri- n-propylethoxysilane, tri-n-propyl n-propoxysilane, tri-n-propylisopropoxysilane, tri n-propyl n-butoxysilane, tri-n-propyl sec-butoxysilane, tri-n-propyl tert-butoxysilane, tri-n-propylphenoxysilane, triisopropylmethoxysilane, triisopropylethoxysilane, triisopropyl n- Propoxysilane, triisopropylisopropoxysilane, triisopropyl n-butoxysilane, triisopropyl sec-butoxysilane, triisopropyl tert-butoxysilane, triisopropylphenoxysilane, tri-n-butylmethoxysilane, tri-n-butylethoxysilane , Tri-n-butyl n-propoxysilane, tri-n-butylisopropoxysilane, tri-n-butyl n-butoxysilane, tri-n-butyl sec-butoxysilane, -N-butyl tert-butoxysilane, tri-n-butylphenoxysilane, tri-sec-butylmethoxysilane, tri-sec-butylisoethoxysilane, tri-sec-butyl n-propoxysilane, tri-c-butyliso Propoxysilane, tri-sec-butyl n-butoxysilane, tri-sec-butylsec-butoxysilane, tri-sec-butyltert-butoxysilane, tri-sec-butylphenoxysilane, tri-tert-butylmethoxysilane, tri -Tert-butylethoxysilane, tri-tert-butyl n-propoxysilane, tri-tert-butylisopropoxysilane, tri-tert-butyl n-butoxysilane, tri-tert-butylsec-butoxysilane, tri-tert- The Til tert-butoxysilane, tri-tert-butylphenoxysilane, triphenylmethoxysilane, triphenylethoxysilane, triphenyl n-propoxysilane, triphenylisopropoxysilane, triphenyl n-butoxysilane, triphenyl sec-butoxysilane , Triphenyl tert-butoxysilane, and triphenylphenoxysilane. These may be used alone or in combination of two or more.

  Particularly preferred compounds as Compound 4 are trimethylmethoxysilane, trimethylethoxysilane, trimethyl n-propoxysilane, trimethylisopropoxysilane, triethylmethoxysilane, triethylethoxysilane, trivinylmethoxysilane, trivinylethoxysilane, triphenylmethoxysilane, And triphenylethoxysilane.

1.4 (D) Component Examples of the basic compound (D) used in the present invention include sodium hydroxide, potassium hydroxide, lithium hydroxide, cerium hydroxide, barium hydroxide, calcium hydroxide, pyridine, and pyrrole. Piperazine, pyrrolidine, piperidine, picoline, ammonia, methylamine, ethylamine, propylamine, butylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, monoethanolamine, diethanolamine, Dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicycloocrane, diazabicyclononane, diazabicycloundecene, urea, tetramethylamine Trimonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, benzyltrimethylammonium hydroxide, choline, and the like. Among these, ammonia, organic amines, and ammonium hydroxides can be mentioned as preferred examples, and tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrapropylammonium hydroxide are particularly preferable. These basic compounds used as component (C) may be used alone or in combination of two or more.

  (D) The usage-amount of a basic compound is 0.00001-1 mol normally with respect to 1 mol of total amounts of (A) component, (B) component, and (C) component, Preferably it is 0.00005-0. 5 moles. If the usage-amount of a basic compound is in the said range, there is little possibility of polymer precipitation or gelation during reaction.

1.5 Production Method of Film-Forming Composition The film-forming composition of the present invention comprises (A) component, (B) component, and (C) component in the presence of (D) component. Can be obtained. In this case, the amount of component (C) used is preferably 1 to 79 parts by weight, preferably 100 parts by weight (in terms of complete hydrolysis condensate) of components (A), (B) and (C). Is 5 to 60 parts by weight.

  Moreover, the usage-amount of (B) component is 1-79 weight part with respect to 100 weight part (total hydrolysis-condensation product conversion) total amount of (A) component, (B) component, and (C) component.

  In this case, the total amount of the component (B) and the component (C) is 10 to 10 parts by weight based on 100 parts by weight of the total amount of the component (A), the component (B) and the component (C) (in terms of complete hydrolysis condensate). 80 parts by weight, preferably 20 to 70 parts by weight. When the total amount of the component (B) and the component (C) is less than 10 parts by weight, it is possible to achieve a low dielectric constant of the silica-based film formed using the produced film-forming composition. On the other hand, when the total amount is larger than 80 parts by weight, the mechanical strength of the silica-based film tends to be lowered.

  The reaction temperature during the hydrolytic condensation is usually 0 to 100 ° C. for 0.1 to 72 hours, preferably 20 to 90 ° C. for about 0.5 to 24 hours. The reaction is usually carried out in an open container or a closed container under a pressure of about 0.05 to 3 MPa.

  The total solid concentration of the film forming composition of the present invention thus obtained is preferably 0.1 to 10% by weight, and is appropriately adjusted according to the purpose of use. When the total solid content concentration of the composition for forming an insulating film of the present invention is 0.1 to 10% by weight, the film thickness of the insulating film is in an appropriate range, and the storage stability is further improved. The total solid content concentration can be adjusted by concentration and dilution with an organic solvent, if necessary.

  When hydrolyzing and condensing component (A), component (B) and component (C), use 0.5 to 150 moles of water per mole of the total amount of components (A), (B) and (C). It is particularly preferable to add 1 to 100 mol of water. When the amount of water to be added is less than 0.5 mol, the crack resistance of the coating film may be inferior, and when it exceeds 150 mol, precipitation or gelation of the polymer may occur during hydrolysis and condensation reactions.

  In this case, it is preferable to use alcohol having a boiling point of 100 ° C. or lower together with water. Here, examples of the alcohol having a boiling point of 100 ° C. or lower include methanol, ethanol, n-propanol, and isopropanol. The amount of the alcohol having a boiling point of 100 ° C. or less is preferably 3 to 100 mol, more preferably 5 to 80 mol, with respect to 1 mol of the total amount of the components (A), (B) and (C).

  Alcohol having a boiling point of 100 ° C. or less may be produced during hydrolysis and / or condensation of the components (A), (B) and (C), and the content thereof is 20% by weight or less, preferably It is preferable to remove it by distillation or the like so as to be 5% by weight or less. Further, as additives, a dehydrating agent such as methyl orthoformate, a further metal complex, or a leveling agent may be contained.

  Moreover, after obtaining a hydrolysis-condensation product from (A) component, (B) component, and (C) component, it is preferable to adjust the pH of the film forming composition of this invention to 7 or less. As a method for adjusting the pH, 1) a method of adding a pH adjusting agent, 2) a method of distilling a basic compound from the composition under normal pressure or reduced pressure, and 3) bubbling a gas such as nitrogen or argon. (Method to remove basic compound from composition) 4) Method to remove basic compound from composition by ion exchange resin 5) Remove basic compound from system by extraction and washing And the like. Each of these methods may be used in combination.

  Examples of the pH adjuster that can be used in the method 1) include inorganic acids and organic acids.

  Examples of inorganic acids include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, phosphoric acid, boric acid, oxalic acid, and the like.

  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, and sebacic acid. Gallic acid, butyric acid, meritic acid, arachidonic acid, shikimic acid, 2-ethylhexanoic acid, oleic acid, stearic acid, linoleic acid, linolenic acid, salicylic acid, benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, Benzenesulfonic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, tartaric acid, succinic acid, fumaric acid, itaconic acid, mesaconic acid, citraconic acid , Malic acid, glutaric acid hydrolyzate, maleic anhydride hydrolyzate, phthalic anhydride Water decomposition products, and the like. These compounds may be used alone or in combination of two or more.

  Finally, the pH of the composition for forming an insulating film is adjusted to 7 or less, preferably 1 to 6. Thus, the effect that the storage stability of the composition obtained improves by adjusting pH in the said range with the said pH adjuster is acquired. The amount of the pH adjuster used is an amount that makes the pH of the composition within the above range, and the amount used is appropriately selected.

1.6 Organic Solvent The above-mentioned hydrolysis condensation can be performed in the presence of an organic solvent. Examples of the organic solvent include at least one selected from the group consisting of alcohol solvents, ketone solvents, amide solvents, ester solvents, and aprotic solvents.

Here, as the alcohol solvent, methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, 2-methyl Butanol, sec-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, heptanol-3, n-octanol, 2- Ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethylheptanol-4, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl 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, pentanediol-2,4, 2-methylpentanediol-2,4, hexanediol-2,5, heptanediol-2,4, 2- Polyhydric alcohol solvents such as ethylhexanediol-1,3, 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 Monomethyl ether, dipropylene glycol monoethyl ether, polyhydric alcohol partial ether solvents such as dipropylene glycol monopropyl ether;
And so on. These alcohol solvents may be used alone or in combination of two or more.

  Examples of ketone solvents 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, and methyl-n-hexyl. In addition to ketone, di-i-butyl ketone, trimethylnonanone, cyclohexanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, acetophenone, fenchon, acetylacetone, 2,4-hexanedione, 2 , 4-heptanedione, 3,5-heptanedione, 2,4-octanedione, 3,5-octanedione, 2,4-nonanedione, 3,5-nonanedione, 5-methyl-2,4-hexanedione, 2,2,6,6-tetramethyl-3, - heptanedione, 1,1,1,5,5,5 beta-diketones such as hexafluoro-2,4-heptane dione and the like. These ketone solvents may be used alone or in combination of two or more.

  Examples of amide solvents include formamide, N-methylformamide, N, N-dimethylformamide, N-ethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-ethylacetamide N, N-diethylacetamide, N-methylpropionamide, N-methylpyrrolidone, N-formylmorpholine, N-formylpiperidine, N-formylpyrrolidine, N-acetylmorpholine, N-acetylpiperidine, N-acetylpyrrolidine, etc. Can be mentioned. These amide solvents may be used alone or in combination of two or more.

  Examples of ester solvents include diethyl carbonate, ethylene carbonate, propylene carbonate, diethyl carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, and i-acetate. -Butyl, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-acetate -Nonyl, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl acetate Glycol 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, dipropylene Glycol acetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-lactate Examples include amyl, diethyl malonate, dimethyl phthalate, and diethyl phthalate. These ester solvents may be used alone or in combination of two or more.

  As aprotic solvents, acetonitrile, dimethyl sulfoxide, N, N, N ′, N′-tetraethylsulfamide, hexamethylphosphoric triamide, N-methylmorpholone, N-methylpyrrole, N-ethylpyrrole, N -Methyl-Δ3-pyrroline, N-methylpiperidine, N-ethylpiperidine, N, N-dimethylpiperazine, N-methylimidazole, N-methyl-4-piperidone, N-methyl-2-piperidone, N-methyl-2 -Pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 1,3-dimethyltetrahydro-2 (1H) -pyrimidinone and the like can be mentioned. These aprotic solvents may be used alone or in combination of two or more.

  As the organic solvent, it is particularly preferable to use a solvent represented by the following general formula (5).

R ⁷ O (CHCH ₃ CH ₂ O) _e R ⁸ (5)
(R ⁷ and R ⁸ each independently represents a monovalent organic group selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or CH ₃ CO—, and e represents an integer of 1 to 2)
Specific examples include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol monopropyl ether. Can do. The above organic solvents can be used alone or in combination of two or more.

1.7 Other Additives Components such as colloidal silica, colloidal alumina, surfactants, and silane coupling agents may be further added to the composition for forming an insulating film of the present invention. Colloidal silica is, for example, a dispersion in which high-purity silicic acid is dispersed in the hydrophilic organic solvent. Usually, the average particle size is 5 to 30 nm, preferably 10 to 20 nm, and the solid content concentration is 10 to 10. About 40% by weight. Examples of such colloidal silica include Nissan Chemical Industries, Ltd., methanol silica sol and isopropanol silica sol; Catalyst Chemical Industries, Ltd., Oscar. Examples of the colloidal alumina include Alumina Sol 520, 100 and 200 manufactured by Nissan Chemical Industries, Ltd .; Alumina Clear Sol, Alumina Sol 10 and 132 manufactured by Kawaken Fine Chemical Co., Ltd., and the like.

  Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and further, fluorine surfactants, silicone surfactants, Polyalkylene oxide surfactants, poly (meth) acrylate surfactants and the like can be mentioned, and fluorine surfactants and silicone surfactants can be preferably mentioned.

  Examples of the fluorosurfactant include 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctyl hexyl ether, octa Ethylene glycol di (1,1,2,2-tetrafluorobutyl) ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl) ether, octapropylene glycol di (1,1,2, , 2-tetrafluorobutyl) ether, hexapropylene glycol di (1,1,2,2,3,3-hexafluoropentyl) ether, sodium perfluorododecyl sulfonate, 1,1,2,2,8,8 , 9,9,10,10-decafluorododecane, 1,1,2,2,3,3-hexafluorodecane, N- [3- (perfluoroo Tansulfonamido) propyl] -N, N′-dimethyl-N-carboxymethyleneammonium betaine, perfluoroalkylsulfonamidopropyltrimethylammonium salt, perfluoroalkyl-N-ethylsulfonylglycine salt, bis (N-perfluorophosphate) Octylsulfonyl-N-ethylaminoethyl), monoperfluoroalkylethyl phosphate ester, etc., a fluorine-based surfactant comprising a compound having a fluoroalkyl or fluoroalkylene group at least at any one of its terminal, main chain and side chain Can be mentioned. Commercially available products include MegaFuck F142D, F172, F173, F173, and F183 (above, Dainippon Ink & Chemicals, Inc.), F-Top EF301, 303, and 352 (made by Shin-Akita Kasei). , FLORARD FC-430, FC-431 (manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC -105, SC-106 (manufactured by Asahi Glass Co., Ltd.), BM-1000, BM-1100 (manufactured by Yusho Co., Ltd.), NBX-15 (Neos Co., Ltd.), etc. Mention may be made of surfactants. Among these, the Megafac F172, BM-1000, BM-1100, and NBX-15 are particularly preferable.

  As the silicone surfactant, for example, SH7PA, SH21PA, SH30PA, ST94PA (all manufactured by Toray Dow Corning Silicone Co., Ltd., etc.) can be used. Among these, the SH28PA and SH30PA are particularly preferable. The amount of the agent used is usually 0.0001 to 10 parts by weight based on component (A) (completely hydrolyzed condensate), and these may be used alone or in combination of two or more.

  Examples of the silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-aminoglycidyloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 1- Methacryloxypropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3- Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl 3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-triethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4 , 7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N -Benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (Oxyethylene)- - aminopropyltrimethoxysilane, etc. N- bis (oxyethylene) -3-aminopropyltriethoxysilane and the like. These may be used alone or in combination of two or more.

2. Film Formation Method and Silica Film Next, a film formation method will be described.

  The method for forming an insulating film of the present invention includes applying the above-described composition for forming an insulating film to a substrate and heating. First, examples of the method for applying to the substrate include spin coating, dipping, roller blades, and spraying. In this case, as a dry film thickness, it is possible to form a coating film having a thickness of about 0.01 to 1.5 μm by one coating and a thickness of about 0.02 to 3 μm by two coatings.

  As a heating method, for example, the coating film can be dried by heating usually at a temperature of about 60 to 600 ° C. for about 1 to 240 minutes. In this case, a hot plate, an oven, a furnace, or the like can be used as the heating method, and the heating atmosphere can be an air atmosphere, a nitrogen atmosphere, an argon atmosphere, a vacuum, a reduced pressure with a controlled oxygen concentration, or the like. Can be done. In heat curing, it is preferably heated to 80 to 450 ° C., more preferably 200 to 420 ° C. in an inert atmosphere or under reduced pressure. Moreover, a coating film can be formed also by irradiating an electron beam or an ultraviolet-ray, and this case is preferable at the point which can shorten drying time.

  The silica-based film of the present invention is obtained by the film forming method described above. Thus obtained using the film-forming composition obtained by hydrolyzing and condensing each of the component (A), the component (B) and the component (C) in the presence of a basic compound at a specified mixing ratio. The silica-based film thus obtained has a low dielectric constant, an excellent elastic modulus, and a good mechanical strength (CMP resistance).

  The silica-based film of the present invention has a uniform film thickness and a low dielectric constant, and is preferable as an interlayer insulating film material. Since this film exhibits a low relative dielectric constant, an interlayer insulating film for semiconductor devices such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM, a protective film such as a surface coat film of a semiconductor device, and a multilayer resist are used. This is useful for applications such as an intermediate layer in a semiconductor manufacturing process, an interlayer insulating film of a multilayer wiring board, a protective film for a liquid crystal display device, and an insulating film.

3. Examples Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In the examples and comparative examples, “parts” and “%” indicate parts by weight and% by weight, respectively, unless otherwise specified. By using the compositions (A-1 to A-5, B-1, and B-2) obtained in Examples 1 to 5 and Comparative Examples 1 and 2, Examples 6 to 10 and Comparative Examples 3 and 4, respectively. A coating film was formed. Each silica-based film thus obtained was evaluated under the following conditions.

3.1 Evaluation method (elastic modulus)
A film-forming composition is applied onto an 8-inch silicon wafer by spin coating, and the wafer is dried on a hot plate at 70 ° C. for 3 minutes and at 200 ° C. for 3 minutes, and further in a nitrogen atmosphere at 420 ° C. The wafer was baked in an oven for 60 minutes. The elastic modulus of the obtained film was measured by a continuous stiffness measurement method using Nanoindenter XP (manufactured by Nano Instruments).

(Relative permittivity)
A film-forming composition is applied onto an 8-inch silicon wafer by spin coating, and the substrate is dried on a hot plate at 80 ° C. for 5 minutes and in a nitrogen atmosphere at 200 ° C. for 5 minutes, and further at 400 ° C. under vacuum. For 1 hour. Next, an aluminum electrode pattern was formed on the obtained film by a vapor deposition method to prepare a sample for measuring a relative dielectric constant. The sample was allowed to stand in a clean room at 23 ° C. and 50% humidity for 2 weeks, and then applied at a frequency of 100 kHz using the HP16451B electrode and HP4284A Precision LCR meter manufactured by Yokogawa-Hewlett-Packard Co. The relative dielectric constant of the film at 23 ° C. was measured.

(CMP resistance of coating film)
A film-forming composition is applied onto an 8-inch silicon wafer by spin coating, and the substrate is dried on a hot plate at 80 ° C. for 5 minutes, in a nitrogen atmosphere at 200 ° C. for 5 minutes, and then in a vacuum atmosphere at 400 ° C. Heated for 1 hour on a hot plate (100 mTorr). The obtained coating film was polished under the following conditions.

Slurry: Silica-hydrogen peroxide system Polishing pressure: 190 g / cm ²
Polishing time: 40 seconds The appearance of the coated film after CMP was observed with a 350,000 lux surface observation lamp and evaluated according to the following criteria.

○: No change ×: Scratches and peeling are confirmed in the coating film.

3.2 Preparation of composition (Examples 1 to 5 and Comparative Examples 1 and 2)
[Example 1]
In a mixed solution of 7.3 g of 40% methylamine aqueous solution, 163.8 g of ultrapure water and 725.2 g of 2-propanol, 57.3 g of tetramethoxysilane (45.2 parts by weight in terms of complete hydrolysis condensate), methyltrimethyl 30.8 g of methoxysilane (30.3 parts by weight in terms of complete hydrolysis condensate) and 15.7 g of trimethylmethoxysilane (24.5 parts by weight in terms of complete hydrolysis condensate) were added and reacted at 70 ° C. for 4 hours. . 666.7 g of propylene glycol monopropyl ether was added to the reaction solution, and the mixture was concentrated under reduced pressure to a total solution amount of 387.9 g. Thereafter, 112.1 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (A-1) having a solid content of 10%.

[Example 2]
In a mixed solution of 2.5 g of 40% methylamine aqueous solution, 556.1 g of ultrapure water, and 884.8 g of 2-propanol, 30.9 g of tetramethoxysilane (54.3 parts by weight in terms of complete hydrolysis condensate), methyltrimethyl 4.6 g of methoxysilane (10.1 parts by weight in terms of complete hydrolysis condensate), 4.1 g of dimethyldimethoxysilane (11.2 parts by weight in terms of complete hydrolysis condensate), and 7.1 g of trimethylmethoxysilane (complete hydrolysis condensation) (24.4 parts by weight in terms of product) was added and reacted at 70 ° C. for 6 hours. 500 g of propylene glycol monopropyl ether was added to the reaction solution, and the mixture was concentrated under reduced pressure to a total solution volume of 187.2 g. Thereafter, 37.8 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (A-2) having a solid content of 10%.

Example 3
In a mixed solution of 20.8 g of 25% tetramethylammonium hydroxide aqueous solution, 642.8 g of ultrapure water and 738.8 g of ethanol, 52.7 g of tetramethoxysilane (46.2 parts by weight in terms of complete hydrolysis condensate), methyl Add 37.7 g of trimethoxysilane (41.3 parts by weight in terms of complete hydrolysis condensate) and 7.2 g of trimethylmethoxysilane (12.5 parts by weight in terms of complete hydrolysis condensate) and react at 60 ° C. for 3 hours. It was. To the reaction solution, 500 g of propylene glycol monopropyl ether was added and concentrated under reduced pressure to a total solution amount of 381.4 g. Thereafter, 68.6 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (A-3) having a solid content of 10%.

Example 4
In a mixed solution of 25% tetramethylammonium hydroxide aqueous solution 66.0 g, ultrapure water 240.4 g and ethanol 1011.0 g, tetramethoxysilane 122.5 g (53.7 parts by weight in terms of complete hydrolysis condensate), dimethyl 32.2 g of dimethoxysilane (22.1 parts by weight in terms of complete hydrolysis condensate) and 28.0 g of trimethylmethoxysilane (24.2 parts by weight in terms of complete hydrolysis condensate) were added and reacted at 60 ° C. for 2 hours. . To the reaction solution, 2000 g of propylene glycol monopropyl ether was added and concentrated under reduced pressure to a total solution amount of 682.6 g. Thereafter, 217.4 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (A-4) having a solid content of 10%.

Example 5
In a mixed solution of 25% tetramethylammonium hydroxide aqueous solution 53.8 g, ultrapure water 278.7 g, and ethanol 834.5 g, tetramethoxysilane 62.2 g (37.8 parts by weight in terms of complete hydrolysis condensate), methyl 49.5 g of trimethoxysilane (37.5 parts by weight in terms of complete hydrolysis condensate), 10.9 g of dimethyldimethoxysilane (10.4 parts by weight in terms of complete hydrolysis condensate), and 10.4 g of methylmethoxydiphenylsilane (completely hydrolyzed) (14.3 parts by weight in terms of decomposition condensate) was added and reacted at 60 ° C. for 1 hour. 866.7 g of propylene glycol monopropyl ether was added to the reaction solution, and the mixture was concentrated under reduced pressure to a total solution amount of 490.5 g. Thereafter, 159.5 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (A-5) having a solid content of 10%.

[Comparative Example 1]
In a mixed solution of 40 g of methylamine aqueous solution 3.0 g, ultrapure water 460.4 g and 2-propanol 977.1 g, tetramethoxysilane 20.2 g (26.6 parts by weight in terms of complete hydrolysis condensate) 18.1 g of methoxysilane (29.7 parts by weight in terms of complete hydrolysis condensate) and 21.3 g of dimethyldimethoxysilane (43.7 parts by weight in terms of complete hydrolysis condensate) were added and reacted at 70 ° C. for 3 hours. . 500 g of propylene glycol monopropyl ether was added to the reaction solution, and the mixture was concentrated under reduced pressure to a total solution amount of 253.8 g. Thereafter, 46.2 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (B-1) having a solid content of 10%.

[Comparative Example 2]
In a mixed solution of 12.7 g of 25% tetramethylammonium hydroxide aqueous solution, 134.3 g of ultrapure water and 982.0 g of ethanol, 19.0 g of tetramethoxysilane (15.6 parts by weight in terms of complete hydrolysis condensate) and trimethyl 52.0 g of methoxysilane (84.4 parts by weight in terms of complete hydrolysis condensate) was added and reacted at 60 ° C. for 4 hours. 400 g of propylene glycol monopropyl ether was added to the reaction solution, and the mixture was concentrated under reduced pressure to a total solution amount of 438.1 g. Thereafter, 41.9 g of a 10% propylene glycol monopropyl ether solution of acetic acid was added to obtain a composition solution (B-2) having a solid content of 10%.

3.3 Formation of Silica Film (Examples 6 to 10 and Comparative Examples 3 to 4)
The composition solutions obtained in Examples 1 to 5 and Comparative Examples 1 and 2 were filtered with a filter having a pore size of 0.02 μm. The filter had no residue and could be filtered.

  The filtered composition solution was applied onto an 8-inch silicon wafer by spin coating, heated in air at 80 ° C. for 5 minutes, then in a nitrogen atmosphere at 200 ° C. for 5 minutes, and further in vacuum at 400 ° C. for 1 hour. Was heated to obtain a colorless and transparent silica-based film.

3.4 Evaluation Results Evaluation was performed under the above-described conditions using the silica-based films obtained in Examples 6 to 10 and Comparative Examples 3 and 4. The results are shown in Table 1.

  As is apparent from Table 1, alkoxylan hydrolysis and / or condensation is performed in the presence of a basic compound, an alcohol having a boiling point of 100 ° C. or less, and water at a monomer mixing ratio within the range defined by the present invention. Thus, it was confirmed that the obtained silica-based film had a low relative dielectric constant, excellent elasticity, and good mechanical strength (CMP resistance) as compared with the comparative example.

Claims (11)

(A) a silane compound represented by the following general formula (1);
Si (OR) ₄ (1)
(In the formula, R 1 represents a monovalent organic group.)
(B) at least one silane compound selected from the group of silane compounds represented by the following general formula (2) and compounds represented by the following general formula (3);
R ¹ Si (OR ² ) ₃ (2)
(In the formula, R ¹ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ² represents a monovalent organic group.)
R ³ ₂ Si (OR ⁴ ) ₂ (3)
(In the formula, R ³ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ⁴ represents a monovalent organic group.)
(C) Silane compound represented by the following general formula (4) R ⁵ ₃ SiOR ⁶ (4)
(Wherein R ⁵ represents a hydrogen atom, a fluorine atom or a monovalent organic group, and R ⁶ represents a hydrogen atom or a monovalent organic group.)
(D) A film-forming composition containing a hydrolysis-condensation product obtained by hydrolysis-condensation in the presence of a basic compound. In claim 1,
The composition for film formation whose (C) component is 1-79 weight part among 100 weight part of whole quantity of the complete hydrolysis-condensation product of (A) component, (B) component, and (C) component. In claim 1 or 2,
A membrane in which the total amount of component (B) and component (C) is 10 to 80 parts by weight out of 100 parts by weight of the total hydrolysis condensate of component (A), component (B) and component (C) Forming composition. In any of claims 1 to 3,
The film-forming composition, wherein the concentrations of the component (A), the component (B), and the component (C) at the time of hydrolysis condensation are 0.1 to 10% by weight (in terms of complete hydrolysis condensate). In any of claims 1 to 4,
(D) The composition for film formation whose usage-amount of a component is 0.00001-1 mol with respect to 1 mol of whole quantity of (A) component, (B) component, and (C) component. In any of claims 1 to 5,
A film-forming composition that hydrolyzes component (A), component (B), and component (C) in the presence of water and an alcohol having a boiling point of 100 ° C or lower. In any one of Claims 1 thru | or 6.
The composition for film formation whose usage-amount of water is 0.5-150 mol with respect to 1 mol of whole quantity of (A) component, (B) component, and (C) component. In any one of Claims 1 thru | or 7,
The composition for film formation whose reaction temperature at the time of hydrolysis condensation is 0 degreeC-100 degreeC. In any of claims 1 to 8,
The composition for film formation containing the solvent represented by following General formula (5).
R ⁷ O (CHCH ₃ CH ₂ O) _e R ⁸ (5)
(R ⁷ and R ⁸ each independently represents a monovalent organic group selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or CH ₃ CO—, and e represents an integer of 1 to 2)   A method for forming a silica-based film, comprising applying the film-forming composition according to claim 1 to a substrate and heating the composition.   A silica-based film obtained by the method for forming a silica-based film according to claim 10.