JP5152464B2 - Insulating film forming composition, silica-based film and method for forming the same - Google Patents

Description

  The present invention relates to a composition for forming an insulating film, a silica-based film, and a method for forming the same.

Conventionally, a silica (SiO ₂ ) film formed by a vacuum process such as a CVD method is frequently 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.

  Usually, an organic silica sol composition for a low relative dielectric constant insulating film used in a semiconductor device is subjected to thermal curing in consideration of the yield in a process in which mechanical stress such as CMP (Chemical Mechanical Polishing) or packaging occurs. The composition of the organic silica sol is controlled so that the obtained organic silica film exhibits a high elastic modulus (for example, US Pat. No. 6,495,264). Specifically, by increasing the tetrafunctional silane compound in the organic silica sol or the silane compound having a larger number of hydrolyzable substituents to usually 40 mol% or more, the absolute crosslinking density in the silica film can be increased. We are trying to improve. By increasing the component ratio of these silane compounds, the crosslinking density increases, and a film having a high elastic modulus and hardness can be obtained. However, since it is difficult to completely react the cross-linked site (silanol) of these silane compounds, when a film made of a silane compound is formed on a substrate and the film is subjected to a cross-linking treatment such as firing, It is known that a large amount of unreacted silanol groups remains and the hygroscopicity of the insulating film increases.

High hygroscopicity of the film is likely to cause defects in many aspects, such as increased leakage current and reduced resistance to chemical species used in semiconductor manufacturing processes such as etching and chemical processing. Therefore, reducing the hygroscopicity of the film is an important issue.
US Pat. No. 6,495,264

  An object of the present invention is to form an insulating film that can be suitably used in a semiconductor element or the like for which high integration and multilayering are desired, has low hygroscopicity, low relative dielectric constant, and excellent mechanical strength. It is providing the composition for insulating film formation which can be used for.

  Another object of the present invention is to provide a silica-based film having a low relative dielectric constant and excellent mechanical strength, and a method for forming the same.

The composition for forming an insulating film according to one embodiment of the present invention includes:
50-100 mol% of at least one silane compound selected from the group of compounds represented by the following general formula (1) and the following general formula (2), and 0-50 mol of other silane compounds A first hydrolytic condensate obtained by hydrolytic condensation of
A second hydrolysis-condensation product obtained by hydrolysis-condensation of at least one silane compound of 30 to 100 mol% represented by the following general formula (1) and another silane compound of 0 to 70 mol%; ,
An organic solvent,
Including
The molecular weight of the second hydrolysis condensate is greater than the molecular weight of the first hydrolysis condensate.
Si (OR ¹ ) ₄ (1)
(In the formula, R ¹ represents a monovalent organic group.)
_{^{R 2 a (R 3 O)}} 3-a Si- (R 6) c -Si (OR 4) 3-b R 5 b ··· (2)
(Wherein R ^{2 to} R ⁵ independently represent a monovalent organic group, a and b each independently represents a number of 0 to 1, and R ⁶ represents an oxygen atom, a phenylene group or — (CH ₂ ) represents a group represented by _m- (where m is an integer of 1 to 6), and c represents 0 or 1.)

In the insulating film forming composition, the other silane compound may include a compound represented by the following general formula (3).
R ⁷ _d Si (OR ⁸ ) _4-d (3)
(In formula, R < ⁷ > -R < ⁸ > represents a monovalent organic group independently, d shows the number of 1-2.)

  In the insulating film forming composition, the ratio of the first hydrolysis condensate to the total amount of the first hydrolysis condensate and the second hydrolysis condensate may be 50 to 95% by mass. .

  The composition for forming an insulating film may further contain an organic polymer as a film hollow hole forming agent.

  The method for forming a silica-based film according to one embodiment of the present invention includes a step of applying the insulating film forming composition to a substrate to form a coating film, and a step of applying a curing treatment to the coating film.

  The silica film according to one embodiment of the present invention is obtained by the method for forming a silica film.

  According to the composition for forming an insulating film, the molecular weight of the second hydrolysis-condensation product is higher than the molecular weight of the first hydrolysis-condensation product, including the first and second hydrolysis-condensation products and the organic solvent. Thus, an insulating film having excellent mechanical strength, low hygroscopicity, and low relative dielectric constant can be formed.

  The silica-based film has a low relative dielectric constant, excellent mechanical strength, and low hygroscopicity.

  Hereinafter, a composition for forming an insulating film according to an embodiment of the present invention, a silica-based film, and a method for forming the same will be described in detail.

1. Composition for Insulating Film Formation and Production Thereof A composition for forming an insulating film according to an embodiment of the present invention includes a compound represented by the following general formula (1) (hereinafter also referred to as “compound 1”) and the following general formula. At least one silane compound selected from the group of compounds represented by formula (2) (hereinafter also referred to as “compound 2”) (hereinafter referred to as “(A
) "Component". ) The first hydrolysis condensate obtained by hydrolytic condensation of 50 to 100 mol% and another silane compound (hereinafter also referred to as "component (B)") 0 to 50 mol%, At least one silane compound represented by the general formula (1) (hereinafter also referred to as “component (C)”) 30 to 100 mol% and other silane compounds (hereinafter also referred to as “component (D)”). A second hydrolysis condensate obtained by hydrolytic condensation of 0 to 70 mol%, and an organic solvent, and the molecular weight of the second hydrolysis condensate is the first hydrolysis condensate. Greater than the molecular weight of
Si (OR ¹ ) ₄ (1)
(In the formula, R ¹ represents a monovalent organic group.)
_{^{R 2 a (R 3 O)}} 3-a Si- (R 6) c -Si (OR 4) 3-b R 5 b ··· (2)
(Wherein R ^{2 to} R ⁵ independently represent a monovalent organic group, a and b each independently represents a number of 0 to 1, and R ⁶ represents an oxygen atom, a phenylene group or — (CH ₂ ) represents a group represented by _m- (where m is an integer of 1 to 6), and c represents 0 or 1.)

  The molecular weight of the second hydrolysis condensate is preferably 2 to 200 times the molecular weight of the first hydrolysis condensate. Moreover, it is preferable that the ratio of the 1st hydrolysis-condensation product with respect to the total amount (100 mass%) of a 1st hydrolysis-condensation product and a 2nd hydrolysis-condensation product is 50-95 mass%, and 70-95 mass. % Is more preferable. When the ratio is less than 50% by mass, the mechanical strength of the formed insulating film may be inferior. On the other hand, when it exceeds 95% by mass, the hygroscopicity of the formed insulating film may be increased.

  Hereinafter, each component used in order to manufacture the composition for insulating film formation concerning this embodiment is demonstrated.

1.1. 1st hydrolysis-condensate In the composition for insulating film formation which concerns on this embodiment, (A) component and (B) component used in order to manufacture the 1st hydrolysis-condensation product are (A) component and When the sum total of (B) component shall be 100 mol%, (A) component is 50-100 mol%, it is preferable that it is 60-100 mol%, and it is more preferable that it is 70-100 mol%. When the component (A) is less than 50 mol%, the mechanical strength of the formed insulating film may be inferior.

  Moreover, each of compound 1 and compound 2 used as the component (A) may be used alone, or both compound 1 and compound 2 may be used.

  The weight average molecular weight of the first hydrolysis-condensation product is preferably 700 or more and less than 10,000, and more preferably 1,000 or more and 8,000 or less. When the weight average molecular weight of the first hydrolysis-condensation product is not in the range of 700 or more and less than 10,000, the hygroscopicity of the formed insulating film may be increased.

1.1.1. (A) Component Compound 1 and Compound 2 that can be used as the component (A) will be described.

1.1.1.1. Compound 1
In the general formula (1), examples of the monovalent organic group represented by R ¹ include an alkyl group, an alkenyl group, an aryl group, an allyl group, and a glycidyl group. Among these, the monovalent organic group represented by R ¹ is preferably an alkyl group or a phenyl group.

  Here, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, and the like. Preferably, the alkyl group has 1 to 5 carbon atoms, and these alkyl groups may be linear or branched. Further, a hydrogen atom may be substituted with a fluorine atom or the like. Examples of the aryl group include a phenyl group, a naphthyl group, a methylphenyl group, an ethylphenyl group, a chlorophenyl group, a bromophenyl group, and a fluorophenyl group. Examples of the alkenyl group include a vinyl group, a propenyl group, a 3-butenyl group, a 3-pentenyl group, and a 3-hexenyl group.

  Specific examples of the compound 1 include, for example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-iso-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxy. Silane, tetraphenoxysilane and the like can be mentioned, and particularly preferred compounds include tetramethoxysilane and tetraethoxysilane. Compound 1 may be used alone or in combination of two or more.

1.1.1-2. Compound 2
In the general formula (2), examples of R ^{2 to} R ⁵ include the same groups as those exemplified as R ^{1 in the} general formula (1).

  In the general formula (2), the compound 2 having c = 0 includes hexamethoxydisilane, hexaethoxydisilane, hexaphenoxydisilane, 1,1,1,2,2-pentamethoxy-2-methyldisilane, 1,1, 1,2,2-pentaethoxy-2-methyldisilane, 1,1,1,2,2-pentaphenoxy-2-methyldisilane, 1,1,1,2,2-pentamethoxy-2-ethyldisilane, 1,1,1,2,2-pentaethoxy-2-ethyldisilane, 1,1,1,2,2-pentaphenoxy-2-ethyldisilane, 1,1,1,2,2-pentamethoxy-2 -Phenyldisilane, 1,1,1,2,2-pentaethoxy-2-phenyldisilane, 1,1,1,2,2-pentaphenoxy-2-phenyldisilane, 1,1,2,2-tetrameth Si-1,2-dimethyldisilane, 1,1,2,2-tetraethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraphenoxy-1,2-dimethyldisilane, 1,1,2 , 2-tetramethoxy-1,2-diethyldisilane, 1,1,2,2-tetraethoxy-1,2-diethyldisilane, 1,1,2,2-tetraphenoxy-1,2-diethyldisilane, , 1,2,2-tetramethoxy-1,2-diphenyldisilane, 1,1,2,2-tetraethoxy-1,2-diphenyldisilane, 1,1,2,2-tetraphenoxy-1,2- Diphenyldisilane, 1,1,2-trimethoxy-1,2,2-trimethyldisilane, 1,1,2-triethoxy-1,2,2-trimethyldisilane, 1,1,2-triphenoxy-1,2, 2-G Methyldisilane, 1,1,2-trimethoxy-1,2,2-triethyldisilane, 1,1,2-triethoxy-1,2,2-triethyldisilane, 1,1,2-triphenoxy-1,2, 2-triethyldisilane, 1,1,2-trimethoxy-1,2,2-triphenyldisilane, 1,1,2-triethoxy-1,2,2-triphenyldisilane, 1,1,2-triphenoxy- 1,2,2-triphenyldisilane, 1,2-dimethoxy-1,1,2,2-tetramethyldisilane, 1,2-diethoxy-1,1,2,2-tetramethyldisilane, 1,2- Diphenoxy-1,1,2,2-tetramethyldisilane, 1,2-dimethoxy-1,1,2,2-tetraethyldisilane, 1,2-diethoxy-1,1,2,2-tetraethyldisilane, 1,2-diphenoxy-1,1,2,2-tetraethyldisilane, 1,2-dimethoxy-1,1,2,2-tetraphenyldisilane, 1,2-diethoxy-1,1,2,2-tetra Examples thereof include phenyldisilane, 1,2-diphenoxy-1,1,2,2-tetraphenyldisilane, and the like.

  Of these, hexamethoxydisilane, hexaethoxydisilane, 1,1,2,2-tetramethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraethoxy-1,2-dimethyldisilane, 1, 1,2,2-tetramethoxy-1,2-diphenyldisilane, 1,2-dimethoxy-1,1,2,2-tetramethyldisilane, 1,2-diethoxy-1,1,2,2-tetramethyl Preferred examples include disilane, 1,2-dimethoxy-1,1,2,2-tetraphenyldisilane, 1,2-diethoxy-1,1,2,2-tetraphenyldisilane, and the like.

  In addition, as the compound 2 in which c = 1 in the general formula (2), bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, bis (tri-n-propoxysilyl) methane, bis (tri-iso) -Propoxysilyl) methane, bis (tri-n-butoxysilyl) methane, bis (tri-sec-butoxysilyl) methane, bis (tri-tert-butoxysilyl) methane, 1,2-bis (trimethoxysilyl) ethane 1,2-bis (triethoxysilyl) ethane, 1,2-bis (tri-n-propoxysilyl) ethane, 1,2-bis (tri-iso-propoxysilyl) ethane, 1,2-bis (tri -N-butoxysilyl) ethane, 1,2-bis (tri-sec-butoxysilyl) ethane, 1,2-bis (tri-tert-butoxy) Silyl) ethane, 1- (dimethoxymethylsilyl) -1- (trimethoxysilyl) methane, 1- (diethoxymethylsilyl) -1- (triethoxysilyl) methane, 1- (di-n-propoxymethylsilyl) -1- (tri-n-propoxysilyl) methane, 1- (di-iso-propoxymethylsilyl) -1- (tri-iso-propoxysilyl) methane, 1- (di-n-butoxymethylsilyl) -1 -(Tri-n-butoxysilyl) methane, 1- (di-sec-butoxymethylsilyl) -1- (tri-sec-butoxysilyl) methane, 1- (di-tert-butoxymethylsilyl) -1- ( Tri-tert-butoxysilyl) methane, 1- (dimethoxymethylsilyl) -2- (trimethoxysilyl) ethane, 1- (diethoxymethylsilane) L) -2- (triethoxysilyl) ethane, 1- (di-n-propoxymethylsilyl) -2- (tri-n-propoxysilyl) ethane, 1- (di-iso-propoxymethylsilyl) -2- (Tri-iso-propoxysilyl) ethane, 1- (di-n-butoxymethylsilyl) -2- (tri-n-butoxysilyl) ethane, 1- (di-sec-butoxymethylsilyl) -2- (tri -Sec-butoxysilyl) ethane, 1- (di-tert-butoxymethylsilyl) -2- (tri-tert-butoxysilyl) ethane, bis (dimethoxymethylsilyl) methane, bis (diethoxymethylsilyl) methane, bis (Di-n-propoxymethylsilyl) methane, bis (di-iso-propoxymethylsilyl) methane, bis (di-n-butoxymethyl) Silyl) methane, bis (di-sec-butoxymethylsilyl) methane, bis (di-tert-butoxymethylsilyl) methane, 1,2-bis (dimethoxymethylsilyl) ethane, 1,2-bis (diethoxymethylsilyl) ) Ethane, 1,2-bis (di-n-propoxymethylsilyl) ethane, 1,2-bis (di-iso-propoxymethylsilyl) ethane, 1,2-bis (di-n-butoxymethylsilyl) ethane 1,2-bis (di-sec-butoxymethylsilyl) ethane, 1,2-bis (di-tert-butoxymethylsilyl) ethane, 1,2-bis (trimethoxysilyl) benzene, 1,2-bis (Triethoxysilyl) benzene, 1,2-bis (tri-n-propoxysilyl) benzene, 1,2-bis (tri-iso-propoxysilyl) ) Benzene, 1,2-bis (tri-n-butoxysilyl) benzene, 1,2-bis (tri-sec-butoxysilyl) benzene, 1,2-bis (tri-tert-butoxysilyl) benzene, 1, 3-bis (trimethoxysilyl) benzene, 1,3-bis (triethoxysilyl) benzene, 1,3-bis (tri-n-propoxysilyl) benzene, 1,3-bis (tri-iso-propoxysilyl) Benzene, 1,3-bis (tri-n-butoxysilyl) benzene, 1,3-bis (tri-sec-butoxysilyl) benzene, 1,3-bis (tri-tert-butoxysilyl) benzene, 1,4 -Bis (trimethoxysilyl) benzene, 1,4-bis (triethoxysilyl) benzene, 1,4-bis (tri-n-propoxysilyl) benzene 1,4-bis (tri-iso-propoxysilyl) benzene, 1,4-bis (tri-n-butoxysilyl) benzene, 1,4-bis (tri-sec-butoxysilyl) benzene, 1,4- Bis (tri-tert-butoxysilyl) benzene and the like can be mentioned.

  Of these, bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, 1,2-bis (trimethoxysilyl) ethane, 1,2-bis (triethoxysilyl) ethane, 1- (dimethoxymethylsilyl) ) -1- (trimethoxysilyl) methane, 1- (diethoxymethylsilyl) -1- (triethoxysilyl) methane, 1- (dimethoxymethylsilyl) -2- (trimethoxysilyl) ethane, 1- (di Ethoxymethylsilyl) -2- (triethoxysilyl) ethane, bis (dimethoxymethylsilyl) methane, bis (diethoxymethylsilyl) methane, 1,2-bis (dimethoxymethylsilyl) ethane, 1,2-bis (di Ethoxymethylsilyl) ethane, 1,2-bis (trimethoxysilyl) benzene, 1,2-bis (triethoxy) Silyl) benzene, 1,3-bis (trimethoxysilyl) benzene, 1,3-bis (triethoxysilyl) benzene, 1,4-bis (trimethoxysilyl) benzene, 1,4-bis (triethoxysilyl) Benzene etc. can be mentioned as a preferable example.

  The compound 2 mentioned above may use 1 type (s) or 2 or more types simultaneously.

1.1.2. Component (B) The other silane compound as component (B) is a hydrolyzable silane compound (a silane compound having a group that can be hydrolyzed during hydrolysis condensation), and is represented by the following general formula (3), for example. It is preferably a compound (hereinafter also referred to as “compound 3”).
R ⁷ _d Si (OR ⁸ ) _4-d (3)
(In formula, R < ⁷ > -R < ⁸ > represents a monovalent organic group independently, d shows the number of 1-2.)

In the general formula (3), examples of the monovalent organic group represented by R ⁷ and R ⁸ include the same groups as those exemplified as R ^{1 in the} general formula (1).

  Specific examples of the compound 3 include, for example, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane, methyltri-sec-butoxysilane, methyltri-tert. -Butoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltriisopropoxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, ethyltri-tert- Butoxysilane, ethyltriphenoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxysilane, n-propyltriisopro Xysilane, 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- Toxisilane, 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- Butyl-n-propoxysilane, tert-butyltriisopropoxysilane, tert-butyltri-n-butoxysilane, tert-butyltri-sec-butoxysilane, tert-butyl Rutri-tert-butoxysilane, tert-butyltriphenoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltriisopropoxysilane, phenyltri-n-butoxysilane, phenyltri-sec -Butoxysilane, phenyltri-tert-butoxysilane, phenyltriphenoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldi-n-propoxysilane, dimethyldiisopropoxysilane, dimethyldi-n-butoxysilane, dimethyldi-sec- Butoxysilane, dimethyldi-tert-butoxysilane, dimethyldiphenoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldi-n-propo Sisilane, diethyldiisopropoxysilane, diethyldi-n-butoxysilane, diethyldi-sec-butoxysilane, diethyldi-tert-butoxysilane, diethyldiphenoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane Di-n-propyldi-n-propoxysilane, di-n-propyldiisopropoxysilane, di-n-propyldi-n-butoxysilane, di-n-propyldi-sec-butoxysilane, di-n-propyldi- tert-butoxysilane, di-n-propyldi-phenoxysilane, diisopropyldimethoxysilane, diisopropyldiethoxysilane, diisopropyldi-n-propoxysilane, diisopropyldiisopropoxysilane, diisopropyldi-n-butoxy Silane, 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-butoxy Silane, di-sec-butyl di-sec-butoxy Sisilane, 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-tert-butyldi-sec-butoxysilane, di-tert-butyldi-tert-butoxysilane, di-tert-butyldi-phenoxy Silane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldi-n-propoxysilane, diphenyldiisopropoxysilane, diphenyldi-n-butoxysilane, diphenyldi-sec-butoxysilane, diphenyldi-ter - butoxysilane include diphenyl phenoxy silanes. These may be used alone or in combination of two or more.

  More preferable compounds as the compound 3 are methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso-propoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxy. Silane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane and the like. These may be used alone or in combination of two or more.

  The compound 3 is more preferably a compound (trifunctional silane compound) in which d is 1 in the general formula (3) in that a film having high mechanical strength can be obtained.

1.2. Second hydrolysis condensate In the insulating film forming composition according to the present embodiment, the component (C) and the component (D) used for producing the second hydrolysis condensate are the component (C) and When the sum total of (D) component is 100 mol%, (C) component is 30-100 mol%, it is preferable that it is 40-90 mol%, and it is more preferable that it is 50-80 mol%. When the component (C) is less than 30 mol%, the formed insulating film may have high hygroscopicity.

  The weight average molecular weight of the second hydrolysis-condensation product is preferably 10,000 to 200,000, and more preferably 20,000 to 100,000. When the weight average molecular weight of the second hydrolysis-condensation product is not in the range of 10,000 to 200,000, the hygroscopicity of the formed insulating film may be increased.

  As the component (C), the above-mentioned compound 1 can be used. Moreover, the above-mentioned compound 3 can be used as (D) component.

1.3. Production of first and second hydrolysis condensates 1.3.1. (C) Catalyst (C) A catalyst can be used in producing the first and second hydrolysis-condensation products. (C) The catalyst is preferably at least one compound selected from a basic compound, an acidic compound, and a metal chelate compound.

  For example, when the first hydrolysis condensate is produced, an acidic compound and / or a metal chelate compound can be used as the (C) catalyst. Moreover, when manufacturing a 2nd hydrolysis-condensation product, a basic compound can be used as (C) catalyst. In this case, the weight average molecular weight of the first hydrolysis condensate can be surely made smaller than the weight average molecular weight of the second hydrolysis condensate.

1.3.1.1-1. Metal chelate compound (C) The metal chelate compound which can be used as a catalyst is represented by the following general formula (4).
R ⁹ _e M (OR ¹⁰ ) _fe (4)
(In the formula, R ⁹ represents a chelating agent, M represents a metal atom, R ¹⁰ represents an alkyl group or an aryl group, f represents a valence of the metal M, and e represents an integer of 1 to f.)

Here, the metal M is preferably at least one metal selected from Group IIIB metals (aluminum, gallium, indium, thallium) and Group IVA metals (titanium, zirconium, hafnium). Titanium, aluminum, zirconium Is more preferable. Examples of the alkyl group or aryl group represented by R ¹⁰ include the alkyl group or aryl group represented by R ¹ in the general formula (1).

  Specific examples of metal chelate compounds include triethoxy mono (acetylacetonato) titanium, tri-n-propoxy mono (acetylacetonato) titanium, triisopropoxy mono (acetylacetonato) titanium, tri-n-butoxy. Mono (acetylacetonato) titanium, tri-sec-butoxy mono (acetylacetonato) titanium, tri-tert-butoxy mono (acetylacetonato) titanium, diethoxybis (acetylacetonato) titanium, di-n -Propoxy bis (acetylacetonato) titanium, diisopropoxy bis (acetylacetonato) titanium, di-n-butoxy bis (acetylacetonato) titanium, di-sec-butoxy bis (acetylacetonato) titanium J-tert-but Si-bis (acetylacetonato) titanium, monoethoxy-tris (acetylacetonato) titanium, mono-n-propoxy-tris (acetylacetonato) titanium, monoisopropoxy-tris (acetylacetonato) titanium, mono-n -Butoxy-tris (acetylacetonato) titanium, mono-sec-butoxy-tris (acetylacetonato) titanium, mono-tert-butoxy-tris (acetylacetonato) titanium, tetrakis (acetylacetonato) titanium, triethoxy mono (Ethyl acetoacetate) titanium, tri-n-propoxy mono (ethyl acetoacetate) titanium, triisopropoxy mono (ethyl acetoacetate) titanium, tri-n-butoxy mono (ethyl acetoacetate) titanium, Re-sec-butoxy mono (ethyl acetoacetate) titanium, tri-tert-butoxy mono (ethyl acetoacetate) titanium, diethoxy bis (ethyl acetoacetate) titanium, di-n-propoxy bis (ethyl acetoacetate) Titanium, diisopropoxy bis (ethyl acetoacetate) titanium, di-n-butoxy bis (ethyl acetoacetate) titanium, di-sec-butoxy bis (ethyl acetoacetate) titanium, di-tert-butoxy bis ( Ethyl acetoacetate) titanium, monoethoxy tris (ethyl acetoacetate) titanium, mono-n-propoxy tris (ethyl acetoacetate) titanium, monoisopropoxy tris (ethyl acetoacetate) titanium, mono-n-butoxy tri Sus (ethyl acetoacetate) titanium, mono-sec-butoxy tris (ethyl acetoacetate) titanium, mono-tert-butoxy tris (ethyl acetoacetate) titanium, tetrakis (ethyl acetoacetate) titanium, mono (acetylacetonate) Titanium chelate compounds such as tris (ethylacetoacetate) titanium, bis (acetylacetonate) bis (ethylacetoacetate) titanium, tris (acetylacetonate) mono (ethylacetoacetate) titanium; triethoxy mono (acetylacetonate) Zirconium, tri-n-propoxy mono (acetylacetonato) zirconium, triisopropoxy mono (acetylacetonato) zirconium, tri-n-butoxy mono (acetylacetonate) Zirconium, tri-sec-butoxy mono (acetylacetonato) zirconium, tri-tert-butoxy mono (acetylacetonato) zirconium, diethoxybis (acetylacetonato) zirconium, di-n-propoxybis (acetylacetate) Nate) zirconium, diisopropoxy bis (acetylacetonato) zirconium, di-n-butoxy bis (acetylacetonato) zirconium, di-sec-butoxy bis (acetylacetonato) zirconium, di-tert-butoxy Bis (acetylacetonato) zirconium, monoethoxytris (acetylacetonato) zirconium, mono-n-propoxytris (acetylacetonato) zirconium, monoisopropoxytris Acetylacetonato) zirconium, mono-n-butoxy-tris (acetylacetonato) zirconium, mono-sec-butoxy-tris (acetylacetonato) zirconium, mono-tert-butoxy-tris (acetylacetonato) zirconium, tetrakis ( Acetylacetonato) zirconium, triethoxy mono (ethyl acetoacetate) zirconium, tri-n-propoxy mono (ethyl acetoacetate) zirconium, triisopropoxy mono (ethyl acetoacetate) zirconium, tri-n-butoxy mono ( Ethyl acetoacetate) zirconium, tri-sec-butoxy mono (ethyl acetoacetate) zirconium, tri-tert-butoxy mono (ethyl acetoacetate) zirconium Konium, diethoxy bis (ethyl acetoacetate) zirconium, di-n-propoxy bis (ethyl acetoacetate) zirconium, diisopropoxy bis (ethyl acetoacetate) zirconium, di-n-butoxy bis (ethyl acetoacetate) Zirconium, di-sec-butoxy bis (ethyl acetoacetate) zirconium, di-tert-butoxy bis (ethyl acetoacetate) zirconium, monoethoxy tris (ethyl acetoacetate) zirconium, mono-n-propoxy tris (ethyl) Acetoacetate) zirconium, monoisopropoxy tris (ethyl acetoacetate) zirconium, mono-n-butoxy tris (ethyl acetoacetate) zirconium, mono-sec-but Si-tris (ethylacetoacetate) zirconium, mono-tert-butoxy-tris (ethylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium, mono (acetylacetonato) tris (ethylacetoacetate) zirconium, bis (acetylacetate) Zirconium chelate compounds such as nattobis (ethylacetoacetate) zirconium, tris (acetylacetonato) mono (ethylacetoacetate) zirconium; triethoxy mono (acetylacetonato) aluminum, tri-n-propoxy mono (acetylacetate) Nato) aluminum, triisopropoxy mono (acetylacetonato) aluminum, tri-n-butoxy mono (acetylacetonato) aluminium , Tri-sec-butoxy mono (acetylacetonato) aluminum, tri-tert-butoxy mono (acetylacetonato) aluminum, diethoxybis (acetylacetonato) aluminum, di-n-propoxybis (acetylacetonate) ) Aluminum, diisopropoxy bis (acetylacetonato) aluminum, di-n-butoxy bis (acetylacetonato) aluminum, di-sec-butoxy bis (acetylacetonato) aluminum, di-tert-butoxy bis (Acetylacetonato) aluminum, monoethoxy tris (acetylacetonato) aluminum, mono-n-propoxy tris (acetylacetonato) aluminum, monoisopropoxy tris (acetylacetate) Tonato) aluminum, mono-n-butoxy tris (acetylacetonato) aluminum, mono-sec-butoxy tris (acetylacetonato) aluminum, mono-tert-butoxy tris (acetylacetonato) aluminum, tetrakis (acetylacetate) Natto aluminum, triethoxy mono (ethyl acetoacetate) aluminum, tri-n-propoxy mono (ethyl acetoacetate) aluminum, triisopropoxy mono (ethyl acetoacetate) aluminum, tri-n-butoxy mono (ethyl aceto) Acetate) aluminum, tri-sec-butoxy mono (ethyl acetoacetate) aluminum, tri-tert-butoxy mono (ethyl acetoacetate) aluminum, di Toxi bis (ethyl acetoacetate) aluminum, di-n-propoxy bis (ethyl acetoacetate) aluminum, diisopropoxy bis (ethyl acetoacetate) aluminum, di-n-butoxy bis (ethyl acetoacetate) aluminum, Di-sec-butoxy bis (ethyl acetoacetate) aluminum, di-tert-butoxy bis (ethyl acetoacetate) aluminum, monoethoxy tris (ethyl acetoacetate) aluminum, mono-n-propoxy tris (ethyl acetoacetate) ) Aluminum, monoisopropoxy tris (ethyl acetoacetate) aluminum, mono-n-butoxy tris (ethyl acetoacetate) aluminum, mono-sec-butoxy tris Ethyl acetoacetate) aluminum, mono-tert-butoxy-tris (ethylacetoacetate) aluminum, tetrakis (ethylacetoacetate) aluminum, mono (acetylacetonato) tris (ethylacetoacetate) aluminum, bis (acetylacetonato) bis ( 1 type or 2 types or more of aluminum chelate compounds, such as ethyl acetoacetate) aluminum and tris (acetylacetonato) mono (ethyl acetoacetate) aluminum, etc. are mentioned.

In _{particular, (CH 3 (CH 3)} HCO) 4-t Ti (CH 3 COCH 2 COCH 3) t, (CH 3 (CH 3) HCO) 4-t Ti (CH 3 COCH 2 COOC 2 H 5) t, _{(C 4 H 9 O) 4} -t Ti (CH 3 COCH 2 COCH 3) t, (C 4 H 9 O) 4-t Ti (CH 3 COCH 2 COOC 2 H 5) t, (C 2 H 5 ( CH ₃ ) CO) _4-t Ti (CH ₃ COCH ₂ COCH ₃ ) _t , (C ₂ H ₅ (CH ₃ ) CO) _4-t Ti (CH ₃ COCH ₂ COOC ₂ H ₅ ) _t , (CH ₃ ( CH ₃ ) HCO) _4-t Zr (CH ₃ COCH ₂ COCH ₃ ) _t , (CH ₃ (CH ₃ ) HCO) _4-t Zr (CH ₃ COCH ₂ COOC ₂ H ₅ ) _t , (C ₄ H ₉ O ) _4-t Zr (CH ₃ COCH ₂ COCH ₃ ) _t , (C ₄ H ₉ O) _4-t Zr (CH ₃ COCH ₂ COOC ₂ H ₅ ) _t , (C ₂ H ₅ (CH ₃ ) CO) _4-t Zr (CH ₃ COCH _{2 COCH 3) t, (C} 2 H 5 (CH 3) CO) 4-t Zr (CH 3 COCH 2 COOC 2 H 5) t, (CH 3 (CH 3) HCO) 3-t Al (CH 3 COCH _{2 COCH 3) t, (CH} 3 (CH 3) HCO) 3-t Al (CH 3 COCH 2 COOC 2 H 5) t, (C 4 H 9 O) 3-t Al (CH 3 COCH 2 COCH 3) _{t, (C 4 H 9 O} ) 3-t Al (CH 3 COCH 2 COOC 2 H 5) t, (C 2 H 5 (CH 3) CO) 3-t Al (CH 3 COCH 2 COCH 3) t, (C ₂ H ₅ (CH ₃ ) CO) _3-t Al (CH ₃ COCH ₂ COOC ₂ H ₅ ) One or more types such as _t are preferred as the metal chelate compound used.

  The amount of the metal chelate compound used is 0.0001 to 10 parts by weight, preferably 0.001 to 5 parts by weight, based on 100 parts by weight of the total amount of silane compounds (in terms of complete hydrolysis condensate). When the use ratio of the metal chelate compound is less than 0.0001 part by weight, the coatability of the coating film may be inferior, and when it exceeds 10 parts by weight, the polymer growth cannot be controlled and gelation may occur.

  When hydrolyzing and condensing a silane compound in the presence of a metal chelate compound, it is preferable to use 0.5 to 20 mol of water per mol of the total amount of silane compounds, and it is particularly preferable to add 1 to 10 mol of water. If the amount of water to be added is less than 0.5 mol, the hydrolysis reaction does not proceed sufficiently, which may cause problems in coating properties and storage stability, and if it exceeds 20 mol, the hydrolysis and condensation reactions may occur. Polymer precipitation or gelation may occur. Moreover, it is preferable that water is added intermittently or continuously.

1.3.1-2. Acidic compound (C) As an acidic compound which can be used as a catalyst, an organic acid or an inorganic acid can be illustrated. Examples of organic acids include acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oxalic acid, maleic acid, methylmalonic acid, adipic acid, sebacic acid, gallic acid 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, benzenesulfone Acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, tartaric acid, maleic anhydride, fumaric acid, itaconic acid, succinic acid, mesaconic acid, Citraconic acid, malic acid, malonic acid, hydrolyzed glutaric acid, hydrolyzed maleic anhydride Object can include hydrolysis products of phthalic anhydride. Examples of inorganic acids include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, and phosphoric acid.

  Of these, organic acids are preferred in that there is little risk of polymer precipitation or gelation during the hydrolysis-condensation reaction, and among these, compounds having a carboxyl group are more preferred, and among them, acetic acid, oxalic acid, maleic acid, formic acid. Particularly preferred are organic acids such as hydrolysates of malonic acid, phthalic acid, fumaric acid, itaconic acid, succinic acid, mesaconic acid, citraconic acid, malic acid, malonic acid, glutaric acid and maleic anhydride. These may be used alone or in combination of two or more.

  The usage-amount of an acidic compound is 0.0001-10 weight part with respect to 100 weight part (total hydrolysis condensate conversion) of the total amount of a silane compound, Preferably it is 0.001-5 weight part. When the amount of the acidic compound used is less than 0.0001 parts by weight with respect to 100 parts by weight of the total amount of the silane compound, the coating property of the coating film may be inferior. The condensation reaction may progress and cause gelation.

  When hydrolyzing and condensing a silane compound in the presence of an acidic compound, it is preferable to use 0.5 to 20 mol of water per mol of the total amount of silane compounds, and it is particularly preferable to add 1 to 10 mol of water. If the amount of water to be added is less than 0.5 mol, the hydrolysis reaction does not proceed sufficiently, which may cause problems in coating properties and storage stability, and if it exceeds 20 mol, the hydrolysis and condensation reactions may occur. Polymer precipitation or gelation may occur. Moreover, it is preferable that water is added intermittently or continuously.

1.3.1-3. Basic compounds (C) Examples of basic compounds that can be used as catalysts include methanolamine, ethanolamine, propanolamine, butanolamine, N-methylmethanolamine, N-ethylmethanolamine, N-propylmethanolamine, N -Butylmethanolamine, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine, N-butylethanolamine, N-methylpropanolamine, N-ethylpropanolamine, N-propylpropanolamine, N-butyl Propanolamine, N-methylbutanolamine, N-ethylbutanolamine, N-propylbutanolamine, N-butylbutanolamine, N, N-dimethylmethanolamine, N, N-diethylmethanol Amine, N, N-dipropylmethanolamine, N, N-dibutylmethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, N, N-dipropylethanolamine, N, N-dibutylethanol Amine, N, N-dimethylpropanolamine, N, N-diethylpropanolamine, N, N-dipropylpropanolamine, N, N-dibutylpropanolamine, N, N-dimethylbutanolamine, N, N-diethylbutanolamine N, N-dipropylbutanolamine, N, N-dibutylbutanolamine, N-methyldimethanolamine, N-ethyldimethanolamine, N-propyldimethanolamine, N-butyldimethanolamine, N-methyldiethanolamine N-ethyldie Nolamine, N-propyldiethanolamine, N-butyldiethanolamine, N-methyldipropanolamine, N-ethyldipropanolamine, N-propyldipropanolamine, N-butyldipropanolamine, N-methyldibutanolamine, N-ethyl Dibutanolamine, N-propyldibutanolamine, N-butyldibutanolamine, N- (aminomethyl) methanolamine, N- (aminomethyl) ethanolamine, N- (aminomethyl) propanolamine, N- (aminomethyl) ) Butanolamine, N- (aminoethyl) methanolamine, N- (aminoethyl) ethanolamine, N- (aminoethyl) propanolamine, N- (aminoethyl) butanolamine, N- (aminopropyl) methano Ruamine, N- (aminopropyl) ethanolamine, N- (aminopropyl) propanolamine, N- (aminopropyl) butanolamine, N- (aminobutyl) methanolamine, N- (aminobutyl) ethanolamine, N- ( Aminobutyl) propanolamine, N- (aminobutyl) butanolamine, methoxymethylamine, methoxyethylamine, methoxypropylamine, methoxybutylamine, ethoxymethylamine, ethoxyethylamine, ethoxypropylamine, ethoxybutylamine, propoxymethylamine, propoxyethylamine, Propoxypropylamine, propoxybutylamine, butoxymethylamine, butoxyethylamine, butoxypropylamine, butoxybutylamine, methylamine , Ethylamine, propylamine, butylamine, N, N-dimethylamine, N, N-diethylamine, N, N-dipropylamine, N, N-dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, tetramethylammonium Hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetramethylethylenediamine, tetraethylethylenediamine, tetrapropylethylenediamine, tetrabutylethylenediamine, methylaminomethylamine, methylaminoethylamine, methylamino Propylamine, methylaminobutylamine, ethylaminomethylamine, ethylaminoethylamine Ethylaminopropylamine, ethylaminobutylamine, propylaminomethylamine, propylaminoethylamine, propylaminopropylamine, propylaminobutylamine, butylaminomethylamine, butylaminoethylamine, butylaminopropylamine, butylaminobutylamine, pyridine, pyrrole, piperazine Pyrrolidine, piperidine, picoline, morpholine, methylmorpholine, diazabicycloocrane, diazabicyclononane, diazabicycloundecene, ammonia, sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, etc. Can do.

The basic compound is particularly preferably a nitrogen-containing compound represented by the following general formula (5) (hereinafter also referred to as “compound 4”).
(X ¹ X ² X ³ X ⁴ N) _g Y (5)

In the general formula (5), X ¹ , X ² , X ³ , and X ⁴ are the same or different and are each a hydrogen atom or an alkyl group having 1 to 20 carbon atoms (preferably a methyl group, an ethyl group, a propyl group, or a butyl group). Hexyl group), hydroxyalkyl group (preferably hydroxyethyl group etc.), aryl group (preferably phenyl group etc.), arylalkyl group (preferably phenylmethyl group etc.), Y is a halogen atom (preferably fluorine) An atom, a chlorine atom, a bromine atom, an iodine atom, etc.), a 1 to 4 valent anionic group (preferably a hydroxy group), and g represents an integer of 1 to 4.

  Specific examples of compound 4 include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetra-iso-propylammonium hydroxide, tetra-n-butylammonium hydroxide, tetra-hydroxide iso-butylammonium hydroxide, tetra-tert-butylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, tetraheptylammonium hydroxide, tetraoctylammonium hydroxide, tetranonylammonium hydroxide, tetradecylammonium hydroxide, Tetraundecyl ammonium hydroxide, tetradodecyl ammonium hydroxide, tetramethylammonium bromide, tetramethylammonium chloride, tetraethylammonium bromide, teto chloride Ethylammonium, tetra-n-propylammonium bromide, tetra-n-propylammonium chloride, tetra-n-butylammonium bromide, tetra-n-butylammonium chloride, hexadecyltrimethylammonium hydroxide, -n-hexabromide Decyltrimethylammonium hydroxide, hydroxide-n-octadecyltrimethylammonium, bromide-n-octadecyltrimethylammonium bromide, cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, benzyltrimethylammonium chloride, didecyldimethylammonium chloride, distearyldimethylammonium chloride, chloride Tridecylmethylammonium, tetrabutylammonium hydrogen sulfate, tributylmethylammonium bromide, trioctyl chloride Methyl ammonium, trilauryl methyl ammonium chloride, benzyl trimethyl ammonium hydroxide, benzyl bromide triethylammonium, and the like are preferable benzyl bromide tributylammonium bromide phenyl trimethyl ammonium, choline and the like. Among these, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetra-n-butylammonium hydroxide, tetramethylammonium bromide, tetramethylammonium chloride, tetraethyl bromide are particularly preferable. Ammonium, tetraethylammonium chloride, tetra-n-propylammonium bromide, tetra-n-propylammonium chloride. Compound 4 may be used alone or in combination of two or more.

  The usage-amount of a basic compound is 0.00001-10 mol normally with respect to 1 mol of total amounts of the hydrolysable group in a silane compound, Preferably it is 0.00005-5 mol.

  When hydrolyzing and condensing a silane compound in the presence of a basic compound, it is preferable to use 0.5 to 20 mol of water per mol of the total amount of silane compounds, and it is particularly preferable to add 1 to 10 mol of water. If the amount of water to be added is less than 0.5 mol, the hydrolysis reaction does not proceed sufficiently, which may cause problems in coating properties and storage stability, and if it exceeds 20 mol, the hydrolysis and condensation reactions may occur. Polymer precipitation or gelation may occur. Moreover, it is preferable that water is added intermittently or continuously.

  When a basic compound is used as the (C) catalyst, an acidic compound may be used after the hydrolysis condensation reaction to adjust the pH of the composition. As the acidic compound used here, the acidic compound exemplified as the catalyst (C) can be used, and it is more preferable to use an organic acid.

1.3.2. Organic solvent Examples of the organic solvent that can be used in producing the first and second hydrolysis-condensation products include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, and sec-butanol. Alcohol solvents such as t-butanol; ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexane Polyhydric alcohol solvents such as diol, 2,4-heptanediol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, Polyhydric alcohol partial ether solvents such as ethylene glycol monopropyl ether and ethylene glycol monobutyl ether; ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide , Dioxolane, 4-methyldioxolane, dioxane, dimethyldioxane, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, and other ether solvents; acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl -N-butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl -N-butyl ketone, methyl-n-hexyl ketone, di-i-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, Examples thereof include ketone solvents such as acetonyl acetone and diacetone alcohol.

  The reaction temperature in the hydrolysis condensation for producing the first and second hydrolysis condensates is 0 to 100 ° C., preferably 20 to 80 ° C., and the reaction time is 30 to 1000 minutes, preferably 30 to 180 minutes. .

1.3.3. Production of Film-Forming Composition The film-forming composition according to this embodiment can be obtained by separately producing the first hydrolysis condensate and the second hydrolysis condensate and mixing them. . For example, by mixing the first composition containing the first hydrolysis condensate and the organic solvent and the second composition containing the second hydrolysis condensate and the organic solvent, according to the present embodiment A film-forming composition can be obtained.

1.4. Organic Solvents Organic solvents that can be used in the composition for forming an insulating film according to this embodiment include alcohol solvents, ketone solvents, amide solvents, ether solvents, ester solvents, aliphatic hydrocarbon solvents, aromatics. And at least one selected from the group of group solvents and halogen-containing solvents.

Examples of alcohol solvents include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, 2-methylbutanol, sec -Pentanol, t-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, full Lil alcohol, phenol, cyclohexanol, methyl cyclohexanol, 3,3,5-trimethyl cyclohexanol, benzyl alcohol, mono-alcohol solvents such as diacetone alcohol;
Ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2 Polyhydric alcohol solvents such as ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol;
Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl Ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol And the like; monomethyl ether, dipropylene glycol monoethyl ether, polyhydric alcohol partial ether solvents such as dipropylene glycol monopropyl ether. These alcohol solvents may be used alone or in combination of two or more.

  Examples of 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. Ketone, di-i-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, diacetone alcohol, acetophenone, Mention may be made of ketone solvents such as fenchon. These ketone solvents may be used alone or in combination of two or more.

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

  As ether solvents, ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane, dimethyldioxane, ethylene Glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-n-hexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether , Ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol Dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol di-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytriglycol, tetraethylene glycol di-n-butyl ether, propylene glycol Monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, diphenyl ether Le, can be mentioned ether solvents such as anisole. These ether solvents may be used alone or in combination of two or more.

  Examples of ester solvents include diethyl carbonate, propylene carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, sec-acetate. Butyl, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methyl cyclohexyl acetate, n-nonyl acetate, methyl acetoacetate , Ethyl acetoacetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n acetate -Butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, glycol diacetate, methoxy acetate Triglycol, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate And ester solvents such as dimethyl phthalate and diethyl phthalate. These ester solvents may be used alone or in combination of two or more.

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

  Examples of aromatic hydrocarbon solvents include benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propyl benzene, i-propyl benzene, diethyl benzene, i-butyl benzene, triethyl benzene, di-i-propyl benzene, Aromatic hydrocarbon solvents such as n-amylnaphthalene and trimethylbenzene can be mentioned. These aromatic hydrocarbon solvents may be used alone or in combination of two or more. Examples of the halogen-containing solvent include halogen-containing solvents such as dichloromethane, chloroform, chlorofluorocarbon, chlorobenzene, and dichlorobenzene.

  In the composition for forming an insulating film according to the present embodiment, it is desirable to use an organic solvent having a boiling point of less than 150 ° C., and examples of the solvent species include alcohol solvents, ether solvents, ketone solvents, and ester solvents. It is particularly desirable to further use one or more of them at the same time.

  These organic solvents may be the same as those used for the synthesis of the hydrolysis condensate, or after the synthesis of the hydrolysis condensate is completed, the organic solvent used for the synthesis is replaced with a desired organic solvent. You can also

  The total solid concentration of the film-forming composition according to one embodiment of the present invention is preferably 0.1 to 20% by mass, and is appropriately adjusted according to the purpose of use. When the total solid content concentration of the film-forming composition according to one embodiment of the present invention is 0.1 to 20% by mass, the film thickness of the coating film is in an appropriate range and has better storage stability. It will be a thing. In addition, adjustment of this total solid content concentration is performed by concentration and dilution with an organic solvent, if necessary.

1.5. Other Additives Components such as organic polymers and surfactants may be further added to the film forming composition according to this embodiment.

1.5.1. Organic Polymer The film forming composition according to the present embodiment can further contain an organic polymer as a film hollow hole forming agent.

  Organic polymers include, for example, polymers having a sugar chain structure, vinylamide polymers, (meth) acrylic polymers, aromatic vinyl compound polymers, dendrimers, polyimides, polyamic acids, polyarylenes, polyamides, poly Examples thereof include quinoxaline, polyoxadiazole, a fluorine-based polymer, and a polymer having a polyalkylene oxide structure.

  Examples of the polymer having a polyalkylene oxide structure include a polymethylene oxide structure, a polyethylene oxide structure, a polypropylene oxide structure, a polytetramethylene oxide structure, and a polybutylene oxide structure.

  Specifically, polyoxymethylene alkyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, ethylene oxide derivative of alkylphenol formalin condensate, polyoxyethylene polyoxy Ether type compounds such as propylene block copolymer, polyoxyethylene polyoxypropylene alkyl ether, ethers such as polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene fatty acid alkanolamide sulfate Ester type compound, polyethylene glycol fatty acid ester, ethylene glycol fat Esters, fatty acid monoglycerides, polyglycerol fatty acid esters, sorbitan fatty acid esters, propylene glycol fatty acid esters, and the like ether ester type compounds such as sucrose fatty acid esters.

  Examples of the polyoxyethylene polyoxypropylene block copolymer include compounds having the following block structure.

− (X ′) ₁ − (Y ′) _m −
-(X ') _1- (Y') _m- (X ') _n-
(Wherein X ′ represents a group represented by —CH ₂ CH ₂ O—, Y ′ represents a group represented by —CH ₂ CH (CH ₃ ) O—, l is 1 to 90, and m is 10 to 99, n represents a number from 0 to 90)

  Among these, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, Ether-type compounds such as polyoxyethylene sorbitol fatty acid esters can be mentioned as more preferred examples. The aforementioned organic polymers may be used alone or in combination of two or more.

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

  The amount of the surfactant used is usually 0.00001 to 1 part by weight with respect to 100 parts by weight of the obtained hydrolysis condensate. These may be used alone or in combination of two or more.

2. Method for Forming Silica-Based Film A method for forming a silica-based film (insulating film) according to an embodiment of the present invention includes a step of applying the film-forming composition to a substrate to form a coating film, and curing to the coating film. And a process of applying a treatment.

Examples of the substrate on which the film-forming composition is applied include Si-containing layers such as Si, SiO ₂ , SiN, SiC, and SiCN. As a method for applying the film-forming composition to the substrate, a coating means such as spin coating, dipping method, roll coating method, spray method or the like is used. After the film forming composition is applied to the substrate, the solvent is removed to form a coating film. In this case, as a dry film thickness, a coating film having a thickness of 0.05 to 2.5 μm can be formed by one coating and a thickness of 0.1 to 5.0 μm can be formed by two coatings. Then, a silica-type film | membrane can be formed by performing a hardening process with respect to the obtained coating film.

  Examples of the curing treatment include heating, irradiation with high energy rays such as electron beams and ultraviolet rays, plasma treatment, and combinations thereof. Heat treatment or a combination of heat treatment and irradiation with high energy rays (ultraviolet rays) is preferable. .

  When hardening by heating, this coating film is heated to 80 to 450 ° C. (preferably 300 ° C. to 450 ° C.) under an inert atmosphere or under reduced pressure. As a heating method at this time, a hot plate, an oven, a furnace, or the like can be used, and a heating atmosphere can be performed under an inert atmosphere or under reduced pressure.

  Moreover, in order to control the curing rate of the coating film, it can be heated stepwise or an atmosphere such as nitrogen, air, oxygen, or reduced pressure can be selected as necessary. Through such a process, a silica-based film can be manufactured.

3. Silica-based film A silica-based film according to an embodiment of the present invention has a low dielectric constant and excellent surface flatness. Therefore, an interlayer for semiconductor elements such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM is used. It is particularly excellent as an insulating film, and it is an etching stopper film, a protective film such as a surface coating film of a semiconductor element, an intermediate layer of a semiconductor manufacturing process using a multilayer resist, an interlayer insulating film of a multilayer wiring board, and a liquid crystal display element It can be suitably used for a protective film or an insulating film. The silica-based film according to this embodiment is useful for a semiconductor device including a copper damascene process.

The silica-based film according to the present embodiment has a relative dielectric constant of preferably 1.8 to 4.0, more preferably 2.0 to 3.5, and an elastic modulus of preferably 2 to 50 GPa. more preferably 3～50GPa, the film density is preferably 0.7~1.8g / cm ^3, more preferably 0.8 to 1.5 g / cm ^3. From these facts, it can be said that the organic silica film according to this embodiment is extremely excellent in insulating film characteristics such as mechanical characteristics, low hygroscopicity, and low relative dielectric constant.

4). EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples. In the examples and comparative examples, “parts” and “%” indicate parts by weight and mass%, respectively, unless otherwise specified.

4.1. Evaluation method Various evaluations were performed as follows.

4.1.1. Dielectric constant measurement, Δk
A film-forming composition was applied onto an 8-inch N-type silicon wafer having a resistivity of 0.1 Ω · cm or less by using a spin coating method, and then on a hot plate at 90 ° C. for 3 minutes, and then in a nitrogen atmosphere The film was dried at 200 ° C. for 3 minutes and further baked for 1 hour in a vertical furnace at 420 ° C. under reduced pressure of 50 mTorr (vacuum atmosphere) to obtain a film.

  An aluminum electrode pattern was formed on the obtained film by a vapor deposition method, and a sample for measuring relative permittivity was prepared. With respect to the sample, the relative dielectric constant of the film at room temperature (24 ° C.) and 200 ° C. was measured by a CV method using an HP 16451B electrode and an HP4284A precision LCR meter manufactured by Agilent, Inc. at a frequency of 100 kHz.

  Δk is the difference between the relative dielectric constant (k @ RT) measured at room temperature (24 ° C.) and 40% RH and the relative dielectric constant (k @ 200 ° C.) measured at 200 ° C. in a dry nitrogen atmosphere ( Δk = k @ RT−k @ 200 ° C.). With this Δk, it is possible to mainly evaluate the increase in relative dielectric constant due to moisture absorption of the film. Usually, when Δk is 0.15 or more, it can be said that the organic silica film has high hygroscopicity.

4.1.2. Evaluation of Elastic Modulus (Young's Modulus) of Film The elastic modulus of the film was measured by a continuous stiffness measurement method. The elastic modulus was measured for a polymer film (silica film) formed by the following method. That is, the composition obtained in each example and comparative example was applied on a silicon wafer by spin coating, and then the substrate was dried on a hot plate at 90 ° C. for 3 minutes and in a nitrogen atmosphere at 200 ° C. for 3 minutes. Further, the substrate was baked on a hot plate in a nitrogen atmosphere at 400 ° C. for 60 minutes to obtain a polymer film having a film thickness of 500 μm, and this polymer film was used for evaluation of elastic modulus.

4.1.3. Weight average molecular weight Mw
The weight average molecular weight (Mw) of the hydrolysis condensate was measured by a size exclusion chromatography (SEC) method under the following conditions.

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

4.2. Production of composition for insulating film formation 4.2.1. Synthesis example 1
In a quartz-separable flask substituted with nitrogen, 60.9 g of methyltrimethoxysilane, 177.3 g of tetramethoxysilane, and 599.1 g of propylene glycol monoethyl ether were added, and the reaction solution was heated to 60 ° C. in a water bath. Then, 2.3 g of 20% oxalic acid aqueous solution and 160.4 g of ultrapure water were added and stirred at 60 ° C. for 5 hours. The solution was concentrated under reduced pressure to a total solution amount of 500 g to a solid content of 20%, diluted with propylene glycol monoethyl ether to a solid content of 10%, and hydrolyzed condensate (first hydrolyzed product). Decomposition condensate) and an organic solvent A were obtained. The weight average molecular weight of the polysiloxane (hydrolyzed condensate) obtained from this synthesis example was 2,300.

4.2.2. Synthesis example 2
101.5 g of methyltrimethoxysilane, 134.1 g of bis (triethoxysilyl) ethane, and 642.3 g of propylene glycol monoethyl ether were added to a quartz separable flask substituted with nitrogen, and this reaction solution was added to a water bath at 60 ° C. Then, 2.2 g of 20% maleic acid aqueous solution and 120.0 g of ultrapure water were added and stirred at 60 ° C. for 5 hours. The solution was concentrated under reduced pressure to a total solution amount of 500 g to a solid content of 20%, diluted with propylene glycol monoethyl ether to a solid content of 10%, and hydrolyzed condensate (first hydrolyzed product). Decomposition condensate) and organic solvent B were obtained. The weight average molecular weight of the polysiloxane (hydrolysis condensate) obtained from this synthesis example was 3,700.

4.2.3. Synthesis example 3
In a quartz-separable flask substituted with nitrogen, 253.3 g of tetramethoxysilane and 506.7 g of propylene glycol monoethyl ether were added and heated to 60 ° C. in a water bath, and then 0.010 g of tetrakis (acetylacetonate) titanium. And 239.9 g of ultrapure water was added and allowed to stir at 60 ° C. for 2 hours. The reaction solution was concentrated under reduced pressure to a total solution amount of 500 g to a solid content of 20%, diluted with propylene glycol monoethyl ether to a solid content of 10%, and then hydrolyzed condensate (first product). Hydrolyzed condensate) and an organic solvent composition C were obtained. The weight average molecular weight of the polysiloxane (hydrolyzed condensate) obtained from this synthesis example was 4,100.

4.2.4. Comparative Synthesis Example 1
101.5 g of methyltrimethoxysilane, 76.0 g of tetramethoxysilane and 643.0 g of propylene glycol monoethyl ether were added into a quartz-separable flask substituted with nitrogen, and after heating to 60 ° C. in a water bath, 20% An oxalic acid aqueous solution (1.9 g) and ultrapure water (137.0 g) were added, and the mixture was stirred at 60 ° C. for 5 hours. The reaction solution was concentrated under reduced pressure to a total solution amount of 500 g to a solid content of 20%, diluted with propylene glycol monoethyl ether to a solid content of 10%, and the hydrolysis condensate and organic solvent were removed. A composition D containing was obtained. The weight average molecular weight of the polysiloxane (hydrolyzed condensate) obtained from this comparative synthesis example was 1,900.

4.2.5. Synthesis example 4
In a quartz-separable flask substituted with nitrogen, 50.7 g of methyltrimethoxysilane, 63.3 g of tetramethoxysilane, and 573.8 g of ethanol were added and heated to 60 ° C. in a water bath, and then 20% tetrapropylammonium. Hydroxide aqueous solution 56.6g and ultrapure water 255.8g were added, and it was made to stir at 60 degreeC for 1 hour. The reaction solution was cooled to 10 ° C. or lower in an ice bath, neutralized by adding 40.4 g of a 20% maleic acid aqueous solution, and the organic phase was concentrated to a total solution amount of 333 g under reduced pressure to contain a solid content. The amount was adjusted to 15%, and then diluted with propylene glycol monoethyl ether to a solid content of 10% to obtain a composition E containing a hydrolysis condensate (second hydrolysis condensate) and an organic solvent. The weight average molecular weight of the polysiloxane (hydrolysis condensate) obtained from this synthesis example was 42,000.

4.2.6. Comparative Synthesis Example 2
In a quartz-separable flask substituted with nitrogen, 76.1 g of methyltrimethoxysilane, 31.7 g of tetramethoxysilane, and 610.8 g of ethanol were added and heated to 60 ° C. in a water bath, and then 20% tetrapropylammonium. 51.0 g of an aqueous hydroxide solution and 230.4 g of ultrapure water were added, and the mixture was stirred at 60 ° C. for 1 hour. The reaction solution was cooled to 10 ° C. or lower in an ice bath, neutralized by adding 36.4 g of a 20% maleic acid aqueous solution, and the organic phase was concentrated to a total solution amount of 333 g under reduced pressure, containing a solid content. After adjusting the amount to 15%, the mixture was diluted with propylene glycol monoethyl ether to a solid content of 10% to obtain a composition F containing a hydrolytic condensate and an organic solvent. The molecular weight of the polysiloxane (hydrolyzed condensate) obtained from this comparative synthesis example was 38,000.

4.3. Formation of film (Examples 1 to 9 and Comparative Examples 1 to 10)
The composition obtained in each synthesis example was mixed at a mass ratio shown in Table 1 to prepare a coating composition. In addition, in an example in which “PE-61” is used as an additive, 60 parts of polyoxyethylene polyoxypropylene block copolymer (trade name “PE-61”, manufactured by Sanyo Chemical Industries, Ltd.) in terms of solid content of polysiloxane. ) Was added to the composition.

  Each coating composition was applied onto an 8-inch silicon wafer by spin coating, and heated in the atmosphere at 80 ° C. for 5 minutes and then at 200 ° C. for 5 minutes under nitrogen. Furthermore, the crosslinking process was implemented by the method shown by each example, and the colorless and transparent film | membrane was formed. The evaluation results of the solution and the film are shown in Table 1.

  As the crosslinking treatment method, heat treatment and ultraviolet irradiation were adopted. The procedure of heat treatment and ultraviolet irradiation is as follows.

4.3.1. Heat treatment The obtained film was heated at 425 ° C. for 1 hour under vacuum.

4.3.2. Ultraviolet irradiation In a chamber having an oxygen partial pressure of 0.01 kPa, ultraviolet rays were irradiated while heating the coating film at 400 ° C. on a hot plate. As the ultraviolet light source, white ultraviolet light having a wavelength of 250 nm or less was used. Since this ultraviolet ray is white ultraviolet ray, the illuminance cannot be measured by an effective method.

４．４．結果の考察
（１）実施例１で得られた膜は、組成物Ａと組成物Ｅとを７０：３０の比で混合して得られた組成物を使用して形成されたものである。実施例１で得られた膜は、組成物Ａのみを使用して形成された膜（比較例１）と比較して、弾性率がほぼ同一であるにも関わらず、比誘電率およびΔｋが大幅に減少していることがわかる。また、実施例２では、組成物Ａおよび組成物Ｅの総量に対する組成物Ａの割合が５０質量％未満である混合物を用いて膜を形成しており、比誘電率やΔｋは低いものの弾性率も明らかに低下しており、機械的強度の観点から好ましくない。さらに、比較例２は、組成物Ｅのかわりに組成物Ｆを使用した以外は実施例１と同様の条件で膜を形成した結果であり、比較例２で得られた膜のΔｋの値は、実施例１で得られた膜のΔｋの値と比較して依然大きく、吸湿性が高い膜であることがわかる。

4.4. Discussion of Results (1) The film obtained in Example 1 was formed using a composition obtained by mixing Composition A and Composition E at a ratio of 70:30. Although the film obtained in Example 1 has substantially the same elastic modulus as that of the film formed using only the composition A (Comparative Example 1), the relative dielectric constant and Δk are It can be seen that there is a significant decrease. In Example 2, the film is formed using a mixture in which the ratio of the composition A to the total amount of the composition A and the composition E is less than 50% by mass, and the elastic modulus is low although the relative dielectric constant and Δk are low. Is also clearly lowered, which is not preferable from the viewpoint of mechanical strength. Furthermore, Comparative Example 2 is the result of forming a film under the same conditions as in Example 1 except that Composition F was used instead of Composition E. The value of Δk of the film obtained in Comparative Example 2 was It can be seen that the film is still larger than the value of Δk of the film obtained in Example 1 and has a high hygroscopicity.

  (2) Examples 3 and 4 and Comparative Examples 3 and 4 were obtained by changing the crosslinking treatment of Examples 1 and 2 and Comparative Examples 1 and 2 from thermal firing to ultraviolet treatment, respectively. The same tendency as in 1) appears.

  (3) The composition used in Examples 5-7 and Comparative Example 5 contains an organic polymer for the purpose of reducing the relative dielectric constant. According to Examples 5 and 6, a film formed using a mixture in which the proportion of the composition B exceeds 50% by mass tends to have a high elastic modulus and a small Δk, and exhibits the effects of the present invention. I understand that.

  (4) In Examples 8 and 9 and Comparative Example 6, a film was formed using a mixture of the composition E synthesized with only the tetrafunctional silane compound (compound 1) and the composition E. Between Examples 8 and 9 and Comparative Example 6, the same relationship as that of Examples 1 and 2 and Comparative Example 1 in (1) described above is established.

  (5) In Comparative Example 7, a mixture of the composition D in which the trifunctional silane compound (the compound 3 in which the d is 1 in the general formula (3) above) is the majority of the raw material is used. In this case, the Δk value of the film obtained in Comparative Example 7 is slightly higher than the Δk value of the film obtained in Examples 1 to 9, and the hygroscopicity is low. I understand. Further, since the composition D is composed of a polysiloxane (hydrolysis condensate) mainly composed of a trifunctional silane compound having originally low crosslinkability, according to Comparative Examples 7 and 8, the composition D It can be seen that the film formed using the film has a low elastic modulus regardless of whether or not the composition E is mixed.

  (6) In Comparative Examples 8 and 9, the compositions E and F were each used alone to form a film, and it can be seen that the elastic modulus of the film obtained in this case was low.

Claims (8)

50-100 mol% of at least one silane compound selected from the group of compounds represented by the following general formula (1) and the following general formula (2), and 0-50 mol of other silane compounds A first hydrolytic condensate obtained by hydrolytic condensation of
A second hydrolysis-condensation product obtained by hydrolysis-condensation of at least one silane compound of 30 to 100 mol% represented by the following general formula (1) and another silane compound of 0 to 70 mol%; ,
An organic solvent,
Including
The composition for forming an insulating film, wherein the molecular weight of the second hydrolysis-condensation product is larger than the molecular weight of the first hydrolysis-condensation product.
Si (OR ¹ ) ₄ (1)
(In the formula, R ¹ represents an alkyl group, an alkenyl group, an aryl group, an allyl group, or a glycidyl group .)
_{^{R 2 a (R 3 O)}} 3-a Si- (R 6) c -Si (OR 4) 3-b R 5 b ··· (2)
(Wherein R ^{2 to} R ⁵ independently represent an alkyl group, an alkenyl group, an aryl group, an allyl group or a glycidyl group , a and b each independently represent a number of 0 to 1, and R ⁶ represents Represents an oxygen atom, a phenylene group or a group represented by — (CH ₂ ) _m — (wherein m is an integer of 1 to 6), and c represents 0 or 1.) In claim 1,
The composition for forming an insulating film, wherein the weight average molecular weight of the first hydrolysis-condensation product is 700 or more and less than 10,000. The composition for forming an insulating film according to claim 1 or 2, wherein the second hydrolysis-condensation product has a weight average molecular weight of 10,000 or more and 500,000 or less. In any of claims 1 to 3,
The said other silane compound is a composition for insulating film formation containing the compound represented by following General formula (3).
R ⁷ _d Si (OR ⁸ ) _4-d (3)
(Wherein R ^{7 to} R ⁸ independently represent an alkyl group, an alkenyl group, an aryl group, an allyl group or a glycidyl group , and d represents a number of 1 to 2). In any of claims 1 to 4,
The composition for insulating film formation whose ratio of this 1st hydrolysis-condensation product with respect to the total amount of said 1st hydrolysis-condensation product and said 2nd hydrolysis-condensation product is 50-95 mass%. In any of claims 1 to 5,
An insulating film forming composition further comprising an organic polymer as a film hollow hole forming agent.   A method for forming a silica-based film, comprising: applying a composition for forming an insulating film according to claim 1 to a substrate to form a coating film; and applying a curing treatment to the coating film. Method.   A silica-based film obtained by the method for forming a silica-based film according to claim 7.