JP2006022314A - Film-forming composition and method for forming film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film-forming composition for forming such a thin film on a substrate of a silicon wafer, a display, a liquid crystal display, a plasma display or a lens, as is transparent and of a low reflectivity and low dielectric constant and also is excellent in the mechanical strengths and in the adhesive property to the substrate, and to provide a method for forming the film. <P>SOLUTION: The film-forming composition contains a silica particle, in which the silanol group existing on the particle surface is treated with a surface modifier having a hydrophobic group, and a polysilane compound. The method for forming a film comprises coating this film-forming composition on a substrate and thereafter treating by heat and/or by light. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a film forming composition and a film forming method. More specifically, on a silicon wafer, display, liquid crystal display, plasma display, or lens substrate, a transparent thin film with a low dielectric constant and excellent mechanical strength and adhesion to the substrate is formed. The present invention relates to a film forming composition and a film forming method.

In order to change the physical and chemical characteristics of the surface of a substrate such as a lens, a liquid crystal display, a plasma display, or a silicon substrate, a film is formed on the surface of the substrate.
For example, a hard coat film is laminated on the surface of glass or synthetic resin for the purpose of preventing the surface of glass or synthetic resin from being damaged.

As inventions related to a hard coat film formed on a substrate surface such as glass or synthetic resin, and a method of forming a hard coat film on a substrate surface, for example, the inventions described in Patent Documents 1 to 3 are known. .
Patent Document 1 discloses a hard coat film made of composite oxide fine particles of cerium oxide and titanium oxide and an organosilicon compound.
Patent Document 2 discloses a hard coat film composed of fine particles obtained by treating titanium oxide fine particles with silica and / or an organosilicon compound and an organosilicon compound.
Patent Document 3 describes a hard coat film containing composite oxide fine particles of titanium oxide and iron oxide, or composite oxide fine particles of titanium oxide, iron oxide and silica.

Furthermore, on the image display surface of an image display device such as a liquid crystal display, in order to improve the visibility, it is required that the reflection of light emitted from an external light source is small.
In response to this, it is known that the reflectance is reduced by coating the surface of a transparent object with a transparent film having a low refractive index. An antireflection film using such a phenomenon is displayed on an image display device. Visibility is improved by providing it on the surface.

As a method of forming an antireflection film formed on an image display surface such as a liquid crystal display, for example, inventions described in Patent Documents 4 to 7 are known.
Patent Document 4 discloses that an antireflection film can be formed from a film-forming composition comprising a fluorine-containing polymer having a hydrolyzable silyl group, a silane compound, and a metal alkoxide chelate complex. It is disclosed.
Patent Document 5 discloses an antireflection film including a copolymer obtained by polymerizing a mixture of a compound having an epoxy group and a fluoroalkyl group and a compound having an epoxy group and a hydrolyzable silyl group. .
Patent Document 6 includes an antiglare hard coat layer, inorganic fine particles having an average particle diameter of 0.001 to 0.2 μm, a hydrolyzate of photocurable organosilane, and a composition containing a fluorine-containing polymer. An antiglare antireflection film having a low refractive index layer having a refractive index in the range of 1.35 to 1.49 and an average reflectance of 450 nm to 650 nm of 1.8% or less is disclosed. Has been.
Non-Patent Document 1 discloses an amorphous fluororesin coating film mainly composed of a novel amorphous fluororesin that is molecularly designed by combining a functional-containing fluoromonomer / crosslinking group-containing fluoromonomer / adhesive group-containing monomer. An antireflective optical coating agent that forms is disclosed.

As another method of reducing the refractive index, there is a method of reducing the refractive index of the entire coating film by making air having a refractive index of 1 smaller than the wavelength of visible light and including it in the coating film. is there.
That is, Patent Document 7 includes a base material, a transparent conductive layer provided on the surface of the base material, and a transparent coating provided on the surface of the transparent conductive layer. The transparent coating is composed of a matrix and inorganic compound particles. The inorganic compound particles are (i) a composite particle comprising a porous particle and a coating layer provided on the surface of the porous particle, or (ii) a cavity inside, and the content is a solvent, A substrate with a transparent coating, which is a hollow particle filled with a gas or a porous material, is disclosed.
Patent Document 8 discloses a low refractive index layer in which hollow fine particles such as hollow silica having cavities therein are dispersed in a binder containing an inorganic component obtained from a hydrolyzed polycondensate of alkoxysilane.

On the other hand, in LSI and ULSI, a multilayer wiring is formed by forming several metal wiring layers on a silicon substrate via an interlayer insulating film.
Conventionally, a silica (SiO ₂ ) film formed by a vapor deposition (CVD) method is frequently used as an interlayer insulating film.

In recent years, the wiring density of LSIs and ULSIs has been miniaturized, and accordingly, the distance between adjacent wirings on the substrate has been reduced.
In order to increase the speed of integrated circuits, it is necessary to reduce the wiring resistance connecting the transistors and the transfer capacity accumulated between the wirings, and the introduction of an interlayer insulating film having a low dielectric constant is required.
Further, the interlayer insulating film is required to have mechanical strength that can sufficiently withstand a chemical polishing (CMP) process.

In order to reduce the dielectric constant of the interlayer insulating film, the film is made porous. As a porous insulating film, for example, in Patent Document 9, for forming an interlayer insulating film obtained by hydrolyzing and polymerizing a silane compound such as tetraalkoxysilane and a metal chelate compound in the presence of an organic solvent. A composition is disclosed.
Patent Document 10 discloses a number average molecular weight obtained by polycondensing an organometallic compound containing one kind of element selected from titanium, zirconium, niobium and tantalum and an organosilicon compound having at least one alkoxyl group in the molecule. A composition for forming an interlayer insulating film mainly containing 500 or more oligomers is disclosed.
Patent Document 11 discloses formation of an interlayer insulating film obtained from an alkoxysilane and / or a partial hydrolyzate thereof, an alkoxysilane containing fluorine, an alkoxide of a metal other than Si and / or a derivative thereof, and an organic solvent. A composition for use is disclosed.

Japanese Patent Laid-Open No. 02-264902 Japanese Patent Laid-Open No. 03-68901 Japanese Patent Laid-Open No. 05-2102 Japanese Patent Laid-Open No. 10-147740 JP 08-313704 A JP 2001-264508 A Japanese Patent Laid-Open No. 2001-167637 JP 2002-225866 A Japanese Patent Laid-Open No. 03-20377 Japanese Patent Laid-Open No. 06-181201 International Publication No. 96/758 Pamphlet The Chemical Times 2003 No.4 Optical coating agent for antireflection

  The hard coat films described in Patent Documents 1 to 3 have the following problems. The hard coat films described in Patent Documents 1 and 2 are inferior in mechanical strength such as scratch resistance and abrasion resistance. The hard cord film described in Patent Document 3 has mechanical strength improved to some extent as compared with the hard coat film described in Patent Documents 1 and 2, but the iron oxide itself has a yellowish color. The hard coat film was also slightly yellowish and had a problem with transparency.

The antireflection films described in Patent Documents 4 to 8 have the following problems.
The antireflection film formed by the film forming composition described in Patent Document 4 has a problem that it does not have a sufficiently low reflectance with respect to light rays irradiated from an external light source.
The antireflection film described in Patent Document 5, the antiglare antireflection film described in Patent Document 6, and the antireflection film described in Non-Patent Document 1 do not have a sufficiently low reflectance, and at the same time, use a fluorine-based material. Therefore, there is a problem that a film cannot be formed in a film shape. Therefore, it is not suitable for use as a transfer type antireflection film in which a high refractive index layer needs to be provided on a low refractive index layer.
Although the method using the hollow silica described in Patent Documents 7 and 8 can reduce the refractive index and reduce the reflectance, heat treatment is required, the base material is limited, and the curing time is reduced. There were problems such as being long and having low mechanical strength.

  On the other hand, in the techniques described in Patent Documents 9 to 11, the film is made porous in order to reduce the dielectric constant. However, although the film was made porous, the dielectric constant of the film could be lowered, but the mechanical strength of the film was lowered and the adhesion between the film and the substrate was lowered. As a result, the interlayer insulating film formed by the techniques described in Patent Documents 9 to 11 did not have mechanical strength that can sufficiently withstand the chemical polishing (CMP) process.

The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is a silica in which silanol groups present on the particle surface are hydrophobized with a surface modifier having a hydrophobic group. The present invention relates to a film-forming composition comprising particles and a polysilane compound.
The invention according to claim 2 is a surface modification in which the silica particles have a hydrophobic group, silanol groups present on the surface of silica particles obtained by hydrolyzing a hydrolyzable silicon compound in the presence of water. It is a silica particle obtained by hydrophobizing with an agent, The film forming composition of Claim 1 characterized by the above-mentioned.
The invention according to claim 3 relates to the film-forming composition according to claim 1 or 2, characterized by containing an organic solvent.
The invention according to claim 4 includes a hydrophobic silica sol in which silica particles hydrophobized with a surface modifier in which silanol groups present on the particle surface have a hydrophobic group are dispersed in an organic solvent, and a polysilane compound The present invention relates to a film-forming composition.
The invention according to claim 5 relates to the film-forming composition according to any one of claims 1 to 4, characterized by containing a fluorine-containing acrylic monomer.
The invention according to claim 6 relates to the film forming composition according to claim 5, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound.
A seventh aspect of the present invention relates to a film forming method, wherein the film forming composition according to any one of the first to sixth aspects is applied on a substrate and then heat-treated and / or light-treated.
The invention according to claim 8 is characterized by comprising a cured product of a composition comprising silica particles treated with a surface modifier in which silanol groups present on the particle surface have a hydrophobic group, and a polysilane compound. The present invention relates to a hard coat film.
The invention according to claim 9 relates to the hard coat film according to claim 8, wherein the composition contains a fluorine-containing acrylic monomer.
The invention according to claim 10 relates to the hard coat film according to claim 9, wherein the fluorinated acrylic monomer forms a block copolymer with a polysilane compound.
The invention according to claim 11 is characterized by comprising a cured product of a composition comprising silica particles treated with a surface modifier in which silanol groups present on the particle surface have a hydrophobic group, and a polysilane compound. The present invention relates to an antireflection film.
The invention according to claim 12 relates to the antireflection film according to claim 11, which contains a fluorine-containing acrylic monomer.
The invention according to claim 13 relates to the antireflection film according to claim 12, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound.
The invention according to claim 14 is characterized by comprising a cured product of a composition comprising silica particles treated with a surface modifier in which silanol groups present on the particle surface have a hydrophobic group, and a polysilane compound. The present invention relates to an interlayer insulating film.
The invention according to claim 15 relates to the interlayer insulating film according to claim 14, wherein the composition contains a fluorine-containing acrylic monomer.
The invention according to claim 16 relates to the interlayer insulating film according to claim 15, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound.

According to the inventions according to claims 1 and 4, the film forming composition is capable of forming a transparent film having a low dielectric constant and excellent mechanical strength and adhesion to the substrate on the substrate surface. You can get things.
According to the invention which concerns on Claim 2, the composition for film formation with few mixing amounts of a metal impurity can be obtained.
According to the invention which concerns on Claim 3, the composition for film formation excellent in the dispersibility of a surface modification silica particle and a polysilane compound can be obtained.
According to the invention which concerns on Claim 5 and 6, the composition for film formation which can form the film | membrane which has water repellency can be obtained.
According to the seventh aspect of the present invention, a transparent film having a low dielectric constant and excellent mechanical strength and adhesion to the substrate can be formed on the substrate surface.
According to the eighth aspect of the present invention, it is possible to provide a hard coat film that is transparent and excellent in adhesion to the substrate and mechanical strength.
According to the invention concerning Claim 9 and 10, the hard-coat film | membrane which has the outstanding water repellency can be provided.
According to the eleventh aspect of the present invention, an antireflection film having high mechanical strength, low reflectance, and excellent visibility can be provided.
According to the invention concerning Claim 12 and 13, the anti-reflective film which has the outstanding water repellency can be provided.
According to the fourteenth aspect of the present invention, it is possible to provide an interlayer insulating film that is transparent and has a low dielectric constant, and that is excellent in adhesion to the substrate and mechanical strength.
According to the invention which concerns on Claim 15 and 16, the interlayer insulation film which has the outstanding water repellency can be provided.

The film forming composition according to the present invention will be described in detail.
The film-forming composition according to the present invention contains silica particles in which some or all of the silanol groups present on the particle surface are hydrophobized with a surface modifier having a hydrophobic group, and a polysilane compound. .
The film-forming composition according to the present invention contains silica particles in which some or all of the silanol groups present on the particle surface are hydrophobized with a surface modifier having a hydrophobic group, and a polysilane compound. Thus, a film having excellent mechanical strength and excellent adhesion to the substrate can be formed. Moreover, the film formed on the substrate by the film forming composition according to the present invention has a low dielectric constant, and can be suitably used as an interlayer insulating film such as a silicon wafer. In addition, the film formed on the substrate by the film forming composition according to the present invention is transparent and excellent in adhesion to the film and mechanical strength, and thus can be suitably used as a hard coat film. .
Furthermore, since the film-forming composition according to the present invention has a low reflectance, it is suitably used as an antireflection film on an image display surface or the like of a liquid crystal display or the like that is required to reflect less light emitted from an external light source. be able to.

The film-forming composition according to the present invention is a silica particle in which part or all of the silanol groups present on the particle surface are hydrophobized with a surface modifier having a hydrophobic group (hereinafter referred to simply as component A). Contain).
Since the component A is treated with a surface modifier having a hydrophobic group in part or all of the silanol groups on the surface of the silica particles, the silica particles are hydrophobic.

  The particle size (specific surface area conversion method) of the silica particles of component A is not particularly limited, and is 1 to 500 nm, preferably 5 to 100 nm, and more preferably 10 to 50 nm. When the particle diameter of the silica particles is less than 1 nm, the silica particles are aggregated, and the film cannot be made porous and a low dielectric constant film may not be formed. When the particle size of the silica particles exceeds 500 nm, the mechanical strength of the film and the adhesion to the substrate may be lowered.

The component A is prepared by hydrolyzing and condensing a hydrolyzable silicon compound to prepare silica particles, and then silanol groups present on the surface of the silica particles are made hydrophobic with a surface modifier having a hydrophobic group. The method of preparing by carrying out a chemical conversion process can be illustrated.
More specifically, first, a hydrolyzable silicon compound is hydrolyzed and condensed in an organic solvent in the presence of water (sol-gel method). Thereby, hydrophilic silica fine particles can be formed.
Examples of the hydrolyzable silicon compound include silicon compounds represented by the general formula 1 (Chemical Formula 1).

[Chemical 1]
R _a Si (R ¹ ) _4-a
(In the formula, R is a hydrogen atom, a hydroxyl group, an alkyl group or an aryl group, R ¹ is an alkoxy group or a halogen atom, and a is an integer of 0 to 3.)

Specific examples of hydrolyzable silicon compounds include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, trimethoxysilane, triethoxysilane, methyltrimethoxysilane, trimethoxyvinylsilane, triethoxyvinylsilane. 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethoxydimethylsilane, dimethoxymethylsilane Diethoxymethylsilane, diethoxy-3-glycidoxypropylmethylsilane, dimethoxydiphenylsilane, dimethoxydimethylphenylsilane, trimethylmethoxysilane Emissions, trimethyl silane, dimethyl silane, and alkoxy silane compounds such as dimethoxy diethoxy silane can be exemplified chlorosilanes such as tetrachlorosilane.
In the present invention, an alkoxysilane compound is preferably used, and tetramethoxysilane and tetraethoxysilane are particularly preferable.
In the present invention, a low condensate obtained by partially hydrolyzing the above silicon compound can also be used.

  Examples of organic solvents include methanol, ethanol, isopropanol, n-butanol, t-butanol, pentanol, alcohols such as ethylene glycol, propylene glycol, and 1,4-butanediol, ketones such as acetone and methyl ethyl ketone, and ethyl acetate. And esters such as paraoctanes such as isooctane and cyclohexane, ethers such as dioxane and diethyl ether, and aromatic compounds such as benzene and toluene.

  In order to hydrolyze and condense a hydrolyzable silicon compound in an organic solvent containing water, the hydrolyzable silicon compound is added to the organic solvent, and the conditions are 0 to 100 ° C., preferably 0 to 70 ° C. Can be stirred. In this manner, spherical and uniform silica particles can be obtained by stirring and hydrolyzing and condensing a hydrolyzable silicon compound in an organic solvent containing water.

Subsequently, the silanol group on the surface of the silica particles is surface-modified with a surface modifier having a hydrophobic group, whereby a dispersion of hydrophobic silica particles can be obtained.
Examples of the surface modifier having a hydrophobic group include a silane coupling agent having both a functional group capable of reacting with a silanol group on the surface of the silica particle and a hydrophobic group. Examples of functional groups capable of reacting with silanol groups include halogen, amino group, imino group, carboxyl group, alkoxyl group and the like. Examples of hydrophobic groups include alkyl groups, phenyl groups, and fluorides thereof.

Specific examples of the surface modifying agent having a hydrophobic group include those represented by the general formula 2 (Chemical Formula 2), and more specifically, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxy. Silane, methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, phenyltrimethoxysilane, benzyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, diethoxymethylphenylsilane, allyltriethoxysilane, vinyltriethoxy Alkoxysilanes having one or more substituted alkyl groups, phenyl groups, vinyl groups, fluoro groups, etc. in the molecule such as silane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane; trimethylchlorosilane, die Such chlorosilanes such as Le dichlorosilane and the like.
Particularly in the present invention, alkoxysilanes having a phenyl group as a hydrophobic group such as phenyltrimethoxysilane are preferably used as the surface modifier. By using alkoxysilanes having a phenyl group as a hydrophobic group as a surface modifier, it is possible to form a film having excellent mechanical strength without phase separation due to interaction with the component B described later. Because.

[Chemical formula 2]
R ² _b SiX _c
(However, R ² is a hydrophobic group such as an alkyl group or a fluoro group, X is a functional group such as a halogen or an alkoxyl group, b is an integer of 1 to 3, and c is an integer of 3 to 1. .)

  In order to surface-modify the silanol group on the surface of the hydrophilic silica particle with a surface modifier having a hydrophobic group, an acid or base is added to the dispersion of the hydrophilic silica particle, and then the surface modification having the hydrophobic group is performed. Surface modification can be performed by adding a quality agent and performing a treatment such as heating.

  In the hydrophobic silica particles produced by the above-described method, it can be confirmed by Si-NMR that the silanol groups present on the surface of the silica particles are surface-modified with a surface modifier. That is, Q2 (about -92 ppm) peak intensity of Si-NMR (corresponding to two Si silanol groups and two siloxane bonds), Q3 (about -101 ppm) peak intensity (Si silanol group number is 1) And the number of siloxane bonds corresponding to three) and Q4 (about −111 ppm) peak intensity (corresponding to four silanol groups in Si). Hydrophobic silica particles in which silanol groups present on the surface of the silica particles are surface-modified with a surface modifier have a Q2 peak intensity ratio and a Q3 peak intensity ratio compared to hydrophilic silica particles that are not surface-modified. It decreases and the Q4 peak intensity ratio increases.

More specifically, in the hydrophilic silica particles whose surface is not modified, the ratio of the Q4 peak intensity to the Q3 peak intensity is 0.6 to 0.85.
On the other hand, in the hydrophobic silica particles obtained by surface-modifying silanol groups on the surface of the hydrophilic silica particles with a surface modifier having a hydrophobic group, the ratio of the Q4 peak intensity to the Q3 peak intensity is 0.9 or more, Preferably it becomes 0.9-1.8.

  In the present invention, the component A may be used as a dispersion of hydrophobic silica particles (hydrophobic silica sol) obtained by the above-described method, or silica obtained by removing the dispersion medium of the hydrophobic silica sol. Particles can also be used.

The film forming composition according to the present invention contains a polysilane compound (hereinafter sometimes simply referred to as B component).
As the polysilane compound, the main skeleton is a linear polysilane and cyclic polysilane represented by the general formula 3 (Chemical Formula 3), the main skeleton is a silicon network polymer represented by the general formula 4 (Chemical Formula 4), and the main skeleton. Examples include at least one polymer selected from the group consisting of a silicon network polymer having a skeleton represented by the general formula 5 (Chemical Formula 5) and a block copolymer of a polysilane compound and a vinyl monomer.

[Chemical formula 3]
(R ³ ₂ Si) _m
(In the formula, R ³ is a hydrogen atom, an alkyl group, an alkenyl group, an arylalkyl group or an aryl group, and may be the same or different. M is an integer of 2 to 10,000.)

[Chemical formula 4]
(R ⁴ Si) _n
(In the formula, R ⁴ is a hydrogen atom, an alkyl group, an alkenyl group, an arylalkyl group or an aryl group, and may be the same or different. N is an integer of 4 to 10,000.)

[Chemical formula 5]
(R ⁵ ₂ Si) _x (R ⁵ Si) _y Si _z
(In the formula, R ⁵ is a hydrogen atom, an alkyl group, an alkenyl group, an arylalkyl group or an aryl group, and may be the same or different. X, y and z are all integers of 1 or more, (The sum of x, y and z is an integer of 5 to 10,000.)

Examples of the alkyl group in the general formula (Chemical Formula 3) to the general formula (Chemical Formula 5) include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, and pentyl. Examples thereof include linear or branched alkyl groups such as a group, isopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group and tetradecyl group.
Examples of the alkenyl group include a vinyl group, 1-propenyl group, allyl group, isopropenyl group, butenyl group, pentenyl group, and the like.

  Examples of the aryl group include a phenyl group, a tosyl group, a benzyl group, a phenethyl group, and a trityl group.

As a block copolymer of a polysilane compound and a vinyl monomer, a block copolymer of a polysilane compound and a fluorine-containing acrylic monomer capable of imparting water repellency is preferable.
This copolymer can be suitably synthesized by a photo radical polymerization method using a polysilane compound as a polymer radical polymerization initiator. In this method, a silyl radical generated by decomposition of a polysilane compound with ultraviolet light is used for polymerization. The composition of the block copolymer can be adjusted by appropriately selecting the concentration of the polysilane compound and the vinyl monomer, the light irradiation intensity, the light irradiation time, and the like.
As the polysilane compound, the above-described polysilane compound can be used.
Examples of the fluorine-containing acrylic monomer include 2,2,2-trifluoroethyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2- (perfluorobutyl) ethyl methacrylate, and 3- (perfluoro Butyl) -2-hydroxypropyl methacrylate, 2- (perfluorohexyl) ethyl methacrylate, 3-perfluorohexyl-2-hydroxypropyl methacrylate, 2- (perfluorooctyl) ethyl methacrylate, 3-perfluorooctyl-2-hydroxy Propyl methacrylate, 2- (perfluorodecyl) ethyl methacrylate, 2- (perfluoro-3-methylbutyl) ethyl methacrylate, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl methacrylate 2- (perfluoro-5-methylhexyl) ethyl methacrylate, 3- (perfluoro-5-methylhexyl) -2-hydroxypropyl methacrylate, 2- (perfluoro-7-methyloctyl) ethyl methacrylate, 3- (Perfluoro-7-methyloctyl) -2-hydroxypropyl methacrylate, 1H, 1H, 3H-tetrafluoropropyl methacrylate, 1H, 1H, 5H-octafluoropentyl methacrylate, 1H, 1H, 7H-dodecafluoroheptyl methacrylate, 1H , 1H, 9H-hexadecafluorononyl methacrylate, 1H-1- (trifluoromethyl) trifluoroethyl methacrylate, methacrylates such as 1H, 1H, 3H-hexafluorobutyl methacrylate, 2,2, -Trifluoroethyl acrylate, 2,2,3,3,3-pentafluoropropyl acrylate, 2- (perfluorobutyl) ethyl acrylate, 2- (perfluorobutyl) ethyl acrylate, 3-perfluorobutyl-2-hydroxy Propyl acrylate, 2- (perfluorohexyl) ethyl acrylate, 3-perfluorohexyl-2-hydroxypropyl acrylate, 2- (perfluorooctyl) ethyl acrylate, 3-perfluorooctyl-2-hydroxypropyl acrylate, 2- ( Perfluorodecyl) ethyl acrylate, 2- (perfluoro-3-methylbutyl) ethyl acrylate, 3- (perfluoro-3-methylbutyl) -2-hydroxypropyl acrylate, 2- (perfluoro-5- Methylhexyl) ethyl acrylate, 3- (perfluoro-5-methylhexyl) -2-hydroxypropyl acrylate, 2- (perfluoro-7-methyloctyl) ethyl acrylate, 3- (perfluoro-7-methyloctyl)- 2-hydroxypropyl acrylate, 1H, 1H, 3H-tetrafluoropropyl acrylate, 1H, 1H, 5H-octafluoropentyl acrylate, 1H, 1H, 7H-dodecafluoroheptyl acrylate, 1H, 1H, 9H-hexadecafluorononyl acrylate Examples thereof include acrylates such as 1H-1- (trifluoromethyl) trifluoroethyl acrylate and 1H, 1H, 3H-hexafluorobutyl acrylate.

  A film having excellent water repellency can be formed by blending a fluorine-containing acrylic monomer with the film-forming composition according to the present invention or by forming a polysilane compound and a block copolymer. The blending amount of the fluorine-containing acrylic monomer is not particularly limited, but if the blending amount of the fluorine-containing acrylic monomer is too small, water repellency may not be imparted, and if the blending amount of the fluorine-containing acrylic monomer is too large, Since there is a case where the synergistic effect of the silica particles and the polysilane compound is adversely affected and the strength of the film is lowered, an appropriate amount is blended in view of the imparted water repellency and the strength of the film.

  In particular, in the present invention, polysilane compounds having an aryl group such as polyalkylphenylsilane and polydiphenylsilane are preferable. By using a polysilane compound having an aryl group as the polysilane compound, it is possible to form a film with no phase separation and excellent mechanical strength due to the interaction with the component A described above.

In the film forming composition according to the present invention, the A component and the B component are usually dissolved or dispersed in an organic solvent.
The organic solvent for dissolving or dispersing the A component and the B component is not particularly limited as long as it does not react with the A component or the B component, and an organic solvent excellent in dispersibility and solubility of the A component and the B component is particularly preferable.
Examples of the organic solvent include cycloaliphatic hydrocarbons such as cyclohexane, methylcyclohexane, and decalin, aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, dodecylbenzene, and methylnaphthalene, methylene chloride, chloroform, ethylene chloride, and chlorobenzene. Halides such as THF, dibutyl ether, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, etc., ethyl acetate, butyl acetate, butyl acrylate, methyl methacrylate, hexamethylene diacrylate, trimethylolpropane tri Examples include esters such as acrylate, ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.
Especially in this invention, it is preferable to use THF, toluene, and xylene among these organic solvents.

The content of component A and component B in the film-forming composition is not particularly limited, but the weight ratio of the content of component A and component B is 1: 1 to 20: 1, preferably 3: 1 to 10: It is preferable to contain so that it may become 1.
When the content of the A component is less than 1 weight times the content of the B component, the dielectric constant of the film formed on the substrate increases, and may not be used as an insulating film. In addition, a film having excellent mechanical strength may not be formed on the substrate. When the content of the A component exceeds 20 times the content of the B component, the adhesion of the film is lowered, and peeling may be a problem.
When used as an antireflection coating on a display screen of a liquid crystal display or the like, the weight ratio of the content of the A component and the B component is preferably 1: 1 to 20: 1, and 3: 1 to 7: 1. : It is more desirable to contain so that it may become.

When a metal compound containing elements such as Fe, Na, K, Ti, Cr, Co, Ni, Cu, Al, Ca, Mg, Pb and Ag is included in the film forming composition, it is formed on the substrate. Since these metals function as electric conductors in the film, the leakage current increases, the film becomes conductive, and does not function as an insulating film.
Therefore, the content of the metal compound contained in the film forming composition according to the present invention is preferably as small as possible.

The film forming composition according to the present invention contains an A component and a B component as essential components. The silica particles as the component A are treated with a surface modifier having a silanol group present on the surface thereof having a hydrophobic group, and therefore, hydrophobic groups are present on the surface of the silica particle. Therefore, when the A component and the B component are mixed by the interaction between the hydrophobic group on the surface of the silica particles and the polysilane compound, they are uniformly dispersed without being separated into two layers. Thereby, a transparent film can be formed on the substrate.
In the case of hydrophilic silica particles in which the silanol groups on the surface of the silica particles are not surface-modified by hydrophobic groups, they cannot be dispersed with the polysilane compound, and the resulting film causes layer separation. Therefore, a film having a low dielectric constant and excellent mechanical strength cannot be formed.

Next, a method for forming the film on the substrate surface by applying the above-described film-forming composition to the substrate will be described.
The method for applying the film to the substrate is not particularly limited, and examples thereof include spin coating, spray coating, printing, casting, curtain coating, and roll coating. In particular, the spin coating method is preferred in the present invention.

The thickness of the film formed on the substrate can be appropriately adjusted depending on the viscosity of the film-forming composition, the spin coating rotational speed, and the like. Specifically, it can be adjusted to an arbitrary thickness of 0.1 μm to 10 μm.
In the case of forming an interlayer insulating film of a semiconductor element, a range of 0.1 μm to 5 μm is preferable.

As the substrate, an insulating substrate such as resin, glass or ceramic, a semiconductor substrate such as silicon or germanium, a compound semiconductor substrate such as gallium-arsenic or indium-antimony, or a substrate in which a conductor layer is formed on these substrates, or Examples thereof include conductor substrates such as aluminum, copper, gold, silver, platinum, chromium, nickel, tungsten, indium, tin, alloys thereof, and metal oxides such as tin oxide. A wiring structure such as a printed wiring board can also be used as the base.
In addition, a glass lens, a plastic lens, a liquid crystal display, a plasma display, or the like can be used as a base.

  Next, the film-forming composition applied to the substrate is dried as necessary. The drying process is performed at normal temperature or under heating under normal pressure, under pressure, or under reduced pressure.

Next, heat treatment and / or light irradiation treatment is performed.
Although the heating temperature in the case of heat processing is not specifically limited, It is 50-500 degreeC, Preferably it is 80-450 degreeC, More preferably, it is 100-400 degreeC.
Although the heating time is not particularly limited, it is 1 minute to 48 hours, preferably 3 minutes to 24 hours, more preferably about 5 minutes to 18 hours.

  The heat treatment can also be performed by arbitrarily combining a temperature raising step, a temperature holding step, and a temperature lowering step.

Examples of the light source used in the light irradiation treatment include a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a helium-cadmium laser, an excimer laser, and a metal halide lamp.
Although the wavelength of the irradiated light is not particularly limited, it is 200 to 400 nm.
The irradiation time of light is not particularly limited, but is 5 seconds to 120 minutes, preferably about 20 seconds to 30 minutes.

  In the present invention, either heat treatment or light irradiation treatment may be performed, but by combining light irradiation treatment and heat treatment, the Si-Si bond of the B component is cleaved even at a relatively low temperature, and the A component A crosslinked structure can be formed, and a film having excellent mechanical properties can be formed.

The relative dielectric constant of the film formed on the substrate by the method as described above is usually 1.3 to 3.0, preferably 1.5 to 2.5.
The refractive index of the film is usually 1.1 to 1.7, preferably 1.2 to 1.5.

The film formed on the surface of the substrate by the method as described above is composed of silica particles treated with a surface modifying agent in which silanol groups present on the particle surface as the A component have hydrophobic groups, and polysilane compounds as the B component. And a cured product of the composition comprising:
Since this film is transparent and has excellent adhesion to the surface of the substrate and mechanical strength, it can be suitably used as a hard coat film for lenses, glass, liquid crystal displays, plasma displays and the like.
Furthermore, since it has high mechanical strength, low reflectance, and excellent visibility, it can be suitably used as an antireflection film in a display screen such as a liquid crystal display.
Further, since this film has a low dielectric constant in addition to the above-described characteristics, it can be suitably used as an interlayer insulating film formed on the surface of a semiconductor wafer or the like.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to these Examples at all.

[Example 1]
To a brown sample bottle, 80 mg of linear polymethylphenylsilane (trade name “Ogsol SI-1010 TYPE-1” manufactured by Osaka Gas Chemical Co., Ltd.) and 3.2 g of distilled xylene are added, and toluene-dispersed silica sol (Fuso Chemical Industries) is added thereto. 1400 mg of a product name “PL-1 Tol” (silica concentration: 40% by weight) was added so that the weight ratio of silica particles to polymethylphenylsilane was 7: 1 to prepare a mixed solution.
This mixed solution was spin-coated on a silicon wafer at 1000 rpm for 30 seconds, and this silicon wafer was irradiated with ultraviolet rays (6000 mJ / cm ² ) with an ultraviolet irradiation device (high pressure mercury lamp).
Next, this silicon wafer was heated from 40 ° C. to 300 ° C. by 10 ° C. per minute by an oven capable of temperature increase, and then baked at 300 ° C. for 30 minutes.
Thereafter, the silicon wafer after baking was further put in an electric furnace set at 400 ° C. at 200 ° C., and the temperature was raised to 400 ° C., followed by baking for 20 minutes.

[Comparative Example a]
To the brown sample bottle, 20 mg of linear polymethylphenylsilane (manufactured by Osaka Gas Chemical Co., Ltd., trade name “Ogsol SI-1010 TYPE-1”) and 0.2 mL of distilled toluene were added.
The mixture was spin-coated on a silicon wafer at 1000-1500 revolutions / minute × 20 seconds, and then heated at 120-130 ° C. for 1 hour.
The silicon wafer was irradiated with ultraviolet rays (6000 mJ / cm ² ) with an ultraviolet irradiation device (high pressure mercury lamp).
Next, this silicon wafer was heated from 40 ° C. to 250 ° C. by 10 ° C. per minute by an oven capable of temperature increase control, and then baked at 250 ° C. for 30 minutes.
This was designated as Comparative Example a.

[Comparative Example b]
Toluene-dispersed silica sol (manufactured by Fuso Chemical Industry Co., Ltd., trade name “PL-1 Tol”, silica concentration 40 wt%) was added to 15 g of distilled toluene to prepare 10 wt% toluene-dispersed silica sol.
Distilled toluene 0.2 mL was added to the brown sample bottle. 2000 mg of 10% strength by weight colloidal silica was added.
The mixture was spin-coated on a silicon wafer at 1000-1500 revolutions / minute × 20 seconds, and then heated at 120-130 ° C. for 1 hour.
The silicon wafer was irradiated with ultraviolet rays (6000 mJ / cm ² ) with an ultraviolet irradiation device (high pressure mercury lamp).
Next, the silicon wafer was heated from 40 ° C. to 250 ° C. by 10 ° C. per minute by an oven capable of temperature increase control, and then baked from 250 ° C. for 30 minutes.
This was designated as Comparative Example b.

  An electron micrograph of toluene-dispersed silica sol (PL-1 Tol) used for the preparation of the sample is shown in FIG. The average particle diameter of the silica particles in the toluene-dispersed silica sol (PL-1 Tol) is 12.7 nm, and some silica particles are dispersed in the dispersion medium in an aggregated state. Silanol groups on the surface of the silica particles are treated with a surface modifier having a phenyl group as a hydrophobic group. Toluene is used as the dispersion medium. The content of silica particles in the toluene-dispersed silica sol (PL-1 Tol) is 39.5% by weight.

[Test Example 1: Measurement of refractive index]
The refractive index of the film in the prepared sample was measured. The refractive index is an ellipsometer (trade name “EMS-1”, ULVAC, He-Ne laser 632.8 nm), and the conditions are “MODE = 50, expected film thickness Do = 10, expected refractive index No = 140”. Set and measure.

[Test Example 2: Measurement of film thickness]
The film thickness of the prepared sample was measured. The film thickness was measured with a finished surface roughness meter (manufactured by Kosaka) by scratching the thin film formed on the silicon wafer so as not to damage the silicon wafer.

[Test Example 3: Measurement of dielectric constant]
The dielectric constant of the film in the prepared sample was measured. The dielectric constant was calculated from the CV curve after performing CV measurement with a mercury proper (manufactured by FOUR DIMENSION) under the conditions of a measurement frequency of 1 MHz and a measurement region of 2.98 × 10 ⁻³ cm ² .

[Test Example 4: Evaluation of adhesion]
The adhesion between the film and the silicon wafer in the prepared sample was evaluated by a four-point bending method.
Specifically, after a film is formed on a 6 cm × 6 cm silicon wafer by spin coating, the silicon wafer cut into the same size on the back side of the coating surface is bonded with EpoTek 375 (manufactured by Epoxy Technology) and dried. did.
The silicon wafer on the side on which the film was formed was cut into a size of 5 mm × 50 mm with a dicing machine. Using a dicing machine, a notch is formed in the silicon wafer on the side on which the film is formed, and adhesion of the film (interfacial fracture energy) is measured by a four-point bending method, using an adhesion evaluation apparatus DTS Delaminator (manufactured by Dauskartt Technical Service). And evaluated. The interfacial fracture energy was calculated by the following formula 1 (Equation 1).

（但し、数１中、ｖはＳｉのポアソン値、Ｌは内側と外側のピン間の距離（１１ｍｍ）であり、ＥはＳｉの弾性係数であり、ｂは測定試料の幅であり、ｈは測定試料の厚さであり、Ｐｃはグラフ上におけるプラトー値である。）

(In the equation 1, v is the Poisson value of Si, L is the distance (11 mm) between the inner and outer pins, E is the elastic modulus of Si, b is the width of the measurement sample, and h is (This is the thickness of the measurement sample, and Pc is the plateau value on the graph.)

[Test Example 5: Elastic modulus and hardness measurement]
The elastic modulus and hardness of the film in the prepared sample were measured by a nanoindentation method using Nano Indenter XP (manufactured by MTS Systems). In the nanoindentation method, the elastic modulus and hardness, which are mechanical properties, can be calculated by analyzing the response of the sample when the indenter is intruded into the sample.
The elastic modulus (E) can be calculated by the following equation 2 (Equation 2), and the hardness (H) can be calculated by the following equation 3 (Equation 3).

（但し、数２及び３中、Ｐは荷重、ｈは押し込み深さであり、ｋ及びβは定数である。）

(However, in Equations 2 and 3, P is a load, h is an indentation depth, and k and β are constants.)

  Example 1 was a film having excellent adhesion to the substrate. On the other hand, Comparative Example b did not become a film having adhesion to the substrate.

[Example 2]
5 g of toluene-dispersed silica sol (PL-1-TOL phenyl modified) having a silica concentration of 40% was precisely weighed and diluted by adding 15 g of toluene to prepare a 10% sol.
0.2 g of polymethylphenylsilane was precisely weighed and diluted by adding 19.8 g of toluene to prepare 20 g of a 1% polymethylphenylsilane solution.
800 mg of the above silica sol was taken, 1200 mg of the above polysilane solution was added thereto, and 800 mg of toluene was further added to prepare an antireflection solution.
This solution is deposited on a PET film and silicon substrate with a spin coater (3000rpm / 20sec), dried at 150 ° C for 5 minutes to remove the solvent, irradiated with UV (16000mJ / cm ² ), and sintered at 150 ° C for 60 minutes. did.
The reflectance and transmittance of the PET film were measured with an ultraviolet-visible spectrophotometer. The minimum reflectance was 0.2%. The transmittance at 600 nm was improved by 6.0%.
A film formed on a silicon substrate was measured for refractive index and film thickness using an ellipsometer. The refractive index was 1.25 and the film thickness was 124 nm.

[Example 3]
10 g of toluene-dispersed silica sol (PL-3-TOL phenyl modified) having a silica concentration of 20% was precisely weighed and diluted by adding 10 g of toluene to prepare a 10% sol.
0.2 g of polymethylphenylsilane was precisely weighed and diluted by adding 19.8 g of toluene to prepare 20 g of a 1% polymethylphenylsilane solution.
800 mg of the above silica sol was taken, 800 mg of the above polysilane solution was added thereto, and 1200 mg of toluene was further added to obtain an antireflection solution.
This solution is deposited on a PET film and silicon substrate with a spin coater (3000rpm / 20sec), dried at 150 ° C for 5 minutes to remove the solvent, irradiated with UV (16000mJ / cm ² ), and sintered at 150 ° C for 60 minutes. did.
The reflectance and transmittance of the PET film were measured with an ultraviolet-visible spectrophotometer. The minimum reflectance was 0.2%. The transmittance at 600 nm was improved by 5.9%.
A film formed on a silicon substrate was measured for refractive index and film thickness using an ellipsometer. The refractive index was 1.23 and the film thickness was 120 nm.

[Example 4]
10 g of toluene-dispersed silica sol (PL-1-TOL acrylic modification + phenyl modification) having a silica concentration of 20% was precisely weighed and diluted by adding 10 g of toluene to prepare a 10% sol.
0.2 g of polymethylphenylsilane was precisely weighed and diluted by adding 19.8 g of toluene to prepare 20 g of a 1% polymethylphenylsilane solution.
1 g of DPHA (dipentaerythritol hexa or pentaacrylate) was precisely weighed and 9 g of toluene was added to dilute to prepare a 10% DPHA solution.
800 mg of the silica sol was taken, 800 mg of the polysilane solution was added thereto, 80 mg of the DPHA solution was added, and 1120 mg of toluene was further added to obtain an antireflection solution.
This solution is deposited on a PET film and silicon substrate with a spin coater (2500rpm / 20sec), dried at 150 ° C for 5 minutes to remove the solvent, irradiated with UV (16000mJ / cm ² ), and sintered at 150 ° C for 60 minutes. did.
The reflectance and transmittance of the PET film were measured with an ultraviolet-visible spectrophotometer. The minimum reflectance was 0.9%. The transmittance at 600 nm was improved by 5.0%.
A film formed on a silicon substrate was measured for refractive index and film thickness using an ellipsometer. The refractive index was 1.29 and the film thickness was 107 nm.

[Example 5]
0.2 g of polymethylphenylsilane was precisely weighed and diluted by adding 19.8 g of toluene to prepare 20 g of a 1% polymethylphenylsilane solution.
800 mg of toluene-dispersed silica sol (PL-1-TOL acrylic modified) having a silica concentration of 10% was taken, 800 mg of the above polysilane solution was added thereto, and 1200 mg of toluene was further added to prepare an antireflection solution.
This solution is deposited on a PET film and silicon substrate with a spin coater (2000rpm / 20sec), dried at 150 ° C for 5 minutes to remove the solvent, irradiated with UV (16000mJ / cm ² ), and sintered at 150 ° C for 60 minutes. did.
The reflectance and transmittance of the PET film were measured with an ultraviolet-visible spectrophotometer. The minimum reflectance was 0.5%. The transmittance at 600 nm was improved by 5.0%.
A film formed on a silicon substrate was measured for refractive index and film thickness using an ellipsometer. The refractive index was 1.27 and the film thickness was 106 nm.

[Example 6]
10 g of toluene-dispersed silica sol (PL-3-TOL phenyl modified) having a silica concentration of 20% was precisely weighed and diluted by adding 10 g of toluene to prepare a 10% sol.
0.2 g of polymethylphenylsilane was precisely weighed and diluted by adding 19.8 g of toluene to prepare 20 g of a 1% polymethylphenylsilane solution.
800 mg of the above silica sol was taken, and 2400 mg of the above polysilane solution was added thereto to give an antireflection solution.
This solution is deposited on a PET film and silicon substrate with a spin coater (3000rpm / 20sec), dried at 150 ° C for 5 minutes to remove the solvent, irradiated with UV (16000mJ / cm ² ), and sintered at 150 ° C for 60 minutes. did.
The reflectance and transmittance of the PET film were measured with an ultraviolet-visible spectrophotometer. The minimum reflectance was 0.3%. The transmittance at 600 nm was improved by 5.4%.
A film formed on a silicon substrate was measured for refractive index and film thickness using an ellipsometer. The refractive index was 1.25 and the film thickness was 117 nm.

  Table 3 shows the compositions of Examples 2 to 6.

From Table 4, it was found that the antireflection films according to Examples 2 to 6 had a low reflectance because the minimum reflectance was low. Further, since no scratch was observed in the rubbing test, it was found that the mechanical strength was strong.
As described above, the film-forming composition according to the present invention has a low reflectance and a high mechanical strength, so that an image display surface such as a liquid crystal display or the like that is required to have little reflection of light irradiated from an external light source, etc. Can be suitably used as an antireflection film having excellent visibility.

The film-forming composition according to the present invention has a low dielectric constant and can form a film having excellent mechanical strength on a substrate, so that an insulating film, particularly an interlayer insulating film of a semiconductor element is formed. It can be suitably used as a film forming composition used in the process. The film-forming composition according to the present invention is transparent and excellent in adhesion to a substrate and mechanical strength, and therefore can be suitably used as a hard coat film. Furthermore, since the film forming composition according to the present invention has a low reflectance, it can be suitably used as an antireflection film.
The film forming method according to the present invention can be suitably used as a method for forming an insulating film, particularly an interlayer insulating film of a semiconductor element. The film forming method according to the present invention can also be suitably used as a method for forming a hard coat film.

It is an electron micrograph of toluene-dispersed silica sol (PL-1 Tol). It is an electron micrograph of an Example.

Claims (16)

A film-forming composition comprising silica particles having a silanol group present on the particle surface hydrophobized with a surface modifier having a hydrophobic group, and a polysilane compound. The silica particles are obtained by hydrophobizing silanol groups present on the surface of silica particles obtained by hydrolyzing a hydrolyzable silicon compound in the presence of water with a surface modifier having a hydrophobic group. The film forming composition according to claim 1, wherein the composition is a silica particle. The film forming composition according to claim 1, further comprising an organic solvent. Film formation characterized by containing a hydrophobic silica sol in which silica particles hydrophobized with a surface modifier whose silanol groups present on the particle surface have a hydrophobic group are dispersed in an organic solvent, and a polysilane compound Composition. The film forming composition according to any one of claims 1 to 4, further comprising a fluorine-containing acrylic monomer. 6. The film-forming composition according to claim 5, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound. A film forming method, comprising: applying a film forming composition according to claim 1 on a substrate, and then performing heat treatment and / or light treatment. A hard coat film comprising a cured product of a composition comprising silica particles in which silanol groups present on the particle surface are treated with a surface modifier having a hydrophobic group, and a polysilane compound. The hard coat film according to claim 8, wherein the composition contains a fluorine-containing acrylic monomer. The hard coat film according to claim 9, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound. An antireflection film comprising a cured product of a composition comprising silica particles in which silanol groups present on the particle surface are treated with a surface modifier having a hydrophobic group, and a polysilane compound. The antireflection film according to claim 11, comprising a fluorine-containing acrylic monomer. The antireflection film according to claim 12, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound. An interlayer insulating film comprising a cured product of a composition comprising silica particles in which silanol groups present on the particle surface are treated with a surface modifier having a hydrophobic group, and a polysilane compound. The interlayer insulating film according to claim 14, wherein the composition contains a fluorine-containing acrylic monomer. The interlayer insulating film according to claim 15, wherein the fluorine-containing acrylic monomer forms a block copolymer with a polysilane compound.

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