JP2001172562A - Film-forming composition and material for forming insulating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a film-forming composition which shows an excellent long- term shelf stability of the solution, yields a coated film which shows an excellent uniformity and mechanical strength and has a dielectric constant of <=2.5 and is therefore suitable as a material for interlayer insulating films for semiconductor elements, etc. SOLUTION: The film-forming composition contains (A) a hydrolysate and/or condensation product obtained by allowing a compound comprising (A-1) a compound of the formula: R1aSi(OR2)4-a, wherein R1 is a hydrogen atom, a fluorine atom or a monovalent organic group; R2 is a monovalent organic group; and a is an integer of 1-2 and (A-2) a compound of the formula: Si(OR2)4, wherein R2 is a monovalent organic group to undergo reaction in the presence of an acid catalyst and water, (B) a propylene glycol monoalkyl ether and (C) a compound having a polyalkylene oxide structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a film-forming composition, and more particularly, to a material for an interlayer insulating film in a semiconductor device or the like, which is excellent in long-term storage stability of a solution, uniformity of a coating film and mechanical strength. And a film forming composition capable of obtaining a coating film having a relative dielectric constant of 2.5 or less.

[0002]

2. Description of the Related Art Conventionally, a silica (SiO ₂ ) film formed by a vacuum process such as a CVD method is often used as an interlayer insulating film in a semiconductor device or the like. In recent years, for the purpose of forming a more uniform interlayer insulating film, a coating-type insulating film mainly composed of a hydrolysis product of tetraalkoxylan, which is called an SOG (Spin on Glass) film, may be used. It has become. Also, with the high integration of semiconductor elements and the like, an interlayer insulating film having a low dielectric constant and mainly containing polyorganosiloxane called organic SOG has been developed. However, with higher integration and multilayering of semiconductor devices and the like, more excellent electrical insulation between conductors is required, and therefore,
There is a demand for an interlayer insulating film material having a lower dielectric constant and excellent surface hardness characteristics.

[0003] Japanese Patent Application Laid-Open No. 6-181201 discloses a coating composition for forming an insulating film having a lower dielectric constant as an interlayer insulating film material. The coating type composition has a low water absorption and is intended to provide an insulating film of a semiconductor device having excellent crack resistance.
Titanium, zirconium, niobium and tantalum; an organometallic compound containing at least one element selected from the group consisting of polycondensation of an organosilicon compound having at least one alkoxy group in the molecule; This is a coating composition for forming an insulating film, which is mainly composed of an oligomer.

[0004] WO96 / 00758 also discloses that
A silica-based coating-type insulating film that is used for forming an interlayer insulating film of a multilayer wiring board and that is made of an alkoxysilane, a metal alkoxide other than silane, and an organic solvent, and that can be applied in a thick film and has excellent oxygen plasma resistance. A forming material is disclosed.

Further, Japanese Patent Application Laid-Open No. Hei 3-20377 discloses a coating liquid for forming an oxide film, which is useful for flattening the surface of electronic parts and the like and for interlayer insulation. The coating solution for forming an oxide film provides a uniform coating solution without generation of a gel-like substance. Further, by using this coating solution, curing at a high temperature and treatment by oxygen plasma are performed. Even so, the purpose is to obtain a good oxide film without cracks. The composition is a coating solution for forming an oxide film obtained by hydrolyzing and polymerizing a predetermined silane compound and a predetermined chelate compound in the presence of an organic solvent.

However, when a metal chelate compound such as titanium or zirconium is combined with a silane compound as described above, the uniformity of the coating film and the long-term storage stability of the solution are not excellent, and the dielectric constant, hygroscopicity and the like are not balanced. I don't have much.

[0007]

The present invention relates to a film-forming composition for solving the above-mentioned problems, and more particularly, to a long-term storage stability of a solution as an interlayer insulating film in a semiconductor device or the like. It is an object of the present invention to provide a material for an interlayer insulating film which is excellent in uniformity and mechanical strength, and is also excellent in balance such as obtaining a coating film having a relative dielectric constant of 2.5 or less.

The present invention relates to (A) (A-1) a compound represented by the following general formula (1): R ¹ _a Si (OR ² ) _4-a (1) wherein R ¹ is hydrogen An atom, a fluorine atom or a monovalent organic group; R ² represents a monovalent organic group; a represents an integer of 1 to 2); and (A-2) represented by the following general formula (2). Hydrolyzate and condensate obtained by reacting a compound consisting of Si (OR ² ) ₄ (2) (R ² represents a monovalent organic group) with an acid catalyst in the presence of water Another object of the present invention is to provide a film-forming composition and a material for forming an insulating film, comprising (B) a propylene glycol monoalkyl ether and (C) a compound having a polyalkylene oxide structure.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Component (A) Component (A-1) The component (A) is prepared by dissolving the components (A-1) and (A-2) in a solvent, adding an acid catalyst and water, A) It is produced by hydrolyzing the component. In the general formula (1), examples of the monovalent organic group represented by R ¹ and R ² include an alkyl group, an aryl group, an allyl group, and a glycidyl group. In the general formula (1), R ¹ is 1
It is preferably a valent organic group, especially an alkyl group or a phenyl group, and R ² is preferably an alkyl group. Here, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group, and preferably have 1 to 1 carbon atoms.
5, these alkyl groups may be chain-like or branched, and a hydrogen atom may be substituted by a fluorine atom or the like. In the general formula (1), examples of the aryl group include a phenyl group, a naphthyl group, a methylphenyl group, an ethylphenyl group, a chlorophenyl group, a bromophenyl group, and a fluorophenyl group.

Specific examples of the compound represented by the general formula (1) include trimethoxysilane, triethoxysilane, tri-n-propoxysilane, tri-iso-propoxysilane, tri-n-butoxysilane and tri-silane. sec-butoxysilane, tri-tert-butoxysilane, triphenoxysilane, fluorotrimethoxysilane, fluorotriethoxysilane, fluorotri-n-propoxysilane, fluorotri-iso-propoxysilane,
Fluorotri-n-butoxysilane, fluorotri-s
ec-butoxysilane, fluorotri-tert-butoxysilane, fluorotriphenoxysilane, etc .; methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso
-Propoxysilane, methyltri-n-butoxysilane, methyltri-sec-butoxysilane, methyltri-tert-butoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltri-iso -Propoxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, ethyltri-tert-butoxysilane, ethyltriphenoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri-n-propoxysilane,
Vinyltri-iso-propoxysilane, vinyltri-
n-butoxysilane, vinyltri-sec-butoxysilane, vinyltri-tert-butoxysilane, vinyltriphenoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxysilane, n- Propyl tri-iso
-Propoxysilane, n-propyltri-n-butoxysilane, n-propyltri-sec-butoxysilane,
n-propyltri-tert-butoxysilane, n-propyltriphenoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, i-propyltri-n-propoxysilane, i-propyltri-
iso-propoxysilane, i-propyltri-n-butoxysilane, i-propyltri-sec-butoxysilane, i-propyltri-tert-butoxysilane,
i-propyltriphenoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-butyltri-n-propoxysilane, n-butyltri-i
so-propoxysilane, n-butyltri-n-butoxysilane, n-butyltri-sec-butoxysilane,
n-butyltri-tert-butoxysilane, n-butyltriphenoxysilane, sec-butyltrimethoxysilane, sec-butyl-i-triethoxysilane, s
ec-butyl-tri-n-propoxysilane, sec-
Butyl-tri-iso-propoxysilane, sec-butyl-tri-n-butoxysilane, sec-butyl-tri-sec-butoxysilane, sec-butyl-tri-
tert-butoxysilane, sec-butyl-triphenoxysilane, t-butyltrimethoxysilane, t-butyltriethoxysilane, t-butyltri-n-propoxysilane, t-butyltri-iso-propoxysilane, t-butyltri-n -Butoxysilane, t-butyltri-sec-butoxysilane, t-butyltri-te
rt-butoxysilane, t-butyltriphenoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltri-n-propoxysilane, phenyltri-iso-propoxysilane, phenyltri-
n-butoxysilane, phenyltri-sec-butoxysilane, phenyltri-tert-butoxysilane, phenyltriphenoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxy Silane, γ-glycidoxypropyltrimethoxysilane,
γ-glycidoxypropyltriethoxysilane, γ-trifluoropropyltrimethoxysilane, γ-trifluoropropyltriethoxysilane, etc .; dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyl-di-n
-Propoxysilane, dimethyl-di-iso-propoxysilane, dimethyl-di-n-butoxysilane, dimethyl-di-sec-butoxysilane, dimethyl-di-te
rt-butoxysilane, dimethyldiphenoxysilane,
Diethyldimethoxysilane, diethyldiethoxysilane, diethyl-di-n-propoxysilane, diethyl-
Di-iso-propoxysilane, diethyl-di-n-butoxysilane, diethyl-di-sec-butoxysilane, diethyl-di-tert-butoxysilane, diethyldiphenoxysilane, di-n-propyldimethoxysilane, di-n -Propyldiethoxysilane, di-n-propyl-di-n-propoxysilane, di-n-propyl-di-iso-propoxysilane, di-n-propyl-
Di-n-butoxysilane, di-n-propyl-di-se
c-butoxysilane, di-n-propyl-di-tert
-Butoxysilane, di-n-propyl-di-phenoxysilane, di-iso-propyldimethoxysilane, di-
iso-propyldiethoxysilane, di-iso-propyl-di-n-propoxysilane, di-iso-propyl-di-iso-propoxysilane, di-iso-propyl-di-n-butoxysilane, di-iso- Propyl-di-sec-butoxysilane, di-iso-propyl-di-tert-butoxysilane, di-iso-propyl-di-phenoxysilane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, Di-n-butyl-di-n-propoxysilane, di-n-butyl-di-iso-propoxysilane, di-n-butyl-di-n
-Butoxysilane, di-n-butyl-di-sec-butoxysilane, di-n-butyl-di-tert-butoxysilane, di-n-butyl-di-phenoxysilane, di-
sec-butyldimethoxysilane, di-sec-butyldiethoxysilane, di-sec-butyl-di-n-propoxysilane, di-sec-butyl-di-iso-propoxysilane, di-sec-butyl-di-n -Butoxysilane, di-sec-butyl-di-sec-butoxysilane, di-sec-butyl-di-tert-butoxysilane, di-sec-butyl-di-phenoxysilane, di-tert-butyldimethoxysilane, -Tert-
Butyldiethoxysilane, di-tert-butyl-di-
n-propoxysilane, di-tert-butyl-di-i
so-propoxysilane, di-tert-butyl-di-
n-butoxysilane, di-tert-butyl-di-se
c-butoxysilane, di-tert-butyl-di-te
rt-butoxysilane, di-tert-butyl-di-phenoxysilane, diphenyldimethoxysilane, diphenyl-di-ethoxysilane, diphenyl-di-n-propoxysilane, diphenyl-di-iso-propoxysilane, diphenyl-di-n -Butoxysilane, diphenyl-di-sec-butoxysilane, diphenyl-di-t
ert-butoxysilane, diphenyldiphenoxysilane, divinyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane , Γ
-Trifluoropropyltrimethoxysilane, γ-trifluoropropyltriethoxysilane, and the like. Preferably, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso-propoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenyltrimethoxysilane Silane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, trimethylmonomethoxysilane, trimethylmonoethoxysilane, triethylmonomethoxysilane, triethyl Particularly preferred compounds such as monoethoxysilane, triphenylmonomethoxysilane, and triphenylmonoethoxysilane It may be mentioned methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane. These may be used alone or in combination of two or more.

(A-2) Component In the above general formula (2), examples of the monovalent organic group for R ² include the same organic groups as those in the above general formula (1), and preferably an alkyl group It is. As the compound represented by the general formula (2), tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-
iso-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-ter
Examples thereof include t-butoxysilane and tetraphenoxysilane. Particularly preferred compounds represented by the general formula (2) are tetramethoxysilane and tetraethoxysilane.

The use ratio of the component (A-1) to the component (A-2) is 100 parts by weight of the component (A-1) (in terms of a completely hydrolyzed condensate) with respect to the component (A-2). To 120 parts by weight (in terms of complete hydrolysis condensate), preferably 10 to 100 parts
Parts by weight. In the present invention, the completely hydrolyzed condensate refers to -OR ^{2 in the} components (A-1) and (A-2).
The group represented by represents 100% hydrolyzed to form an OH group, which is completely condensed.

In the present invention, the component (A-1) and the component (A)
-2) As organic solvents for dissolving the components, aromatic hydrocarbon solvents, alcohol solvents, polyhydric alcohol solvents,
Ketone solvents, ester solvents, ether solvents and the like can be mentioned. Examples of the organic solvent used in the present invention include n-pentane, i-pentane, n-hexane, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane, n-octane and i-pentane. Aliphatic hydrocarbon solvents such as octane, cyclohexane and methylcyclohexane; benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-
Aromatic hydrocarbon solvents such as propylbenzene, i-propylbenzene, diethylbenzene, i-butylbenzene, triethylbenzene, di-i-propylbenzene, n-amylnaphthalene and trimethylbenzene; 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, heptanol-3, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethylheptanol -4, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, s
ec-heptadecyl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-
Trimethylcyclohexanol, benzyl alcohol,
Phenylmethylcarbinol, diacetone alcohol,
Monoalcohol solvents such as cresol; ethylene glycol, propylene glycol, 1,3-butylene glycol, pentanediol-2,4,2-methylpentanediol-2,4, hexanediol-2,5, heptanediol-2, 4,2-ethylhexanediol-
Polyhydric alcohol solvents such as 1,3, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, and glycerin; 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, cyclohexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, diacetone Ketone solvents such as acetone alcohol, acetophenone and fenchone; ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide,
Dioxolan, 4-methyldioxolan, dioxane,
Dimethyl dioxane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-
n-hexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethyl butyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, 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 monomer Ether solvents such as toluene ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tetrahydrofuran and 2-methyltetrahydrofuran; diethyl carbonate, methyl acetate, ethyl acetate, γ -Butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-acetic acid
-Butyl, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, acetic acid Methylcyclohexyl acetate, n-nonyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, propylene acetate 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,
Methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate,
Ester solvents such as ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate; N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide;
Acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropionamide, N-
Nitrogen-containing solvents such as methylpyrrolidone; sulfur-containing solvents such as dimethyl sulfide, diethyl sulfide, thiophene, tetrahydrothiophene, dimethyl sulfoxide, sulfolane, and 1,3-propane sultone; and the like, preferably propylene glycol monomethyl ether , Propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether , Dipropylene glycol monopropyl ether, dipropylene glyco Monobutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dipropyl ether, dipropylene glycol dibutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol mono Butyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monopropyl ether acetate, dipropylene glycol monobutyl ether acetate, propylene glycol diacetate,
Dipropylene glycol diacetate, propylene glycol and the like, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol monomethyl ether acetate, Propylene glycol monoethyl ether acetate and propylene glycol monopropyl ether acetate are particularly preferred from the viewpoint of storage stability of the solution.
These can be used alone or in combination of two or more. Preferably, propylene glycol monoalkyl ether described below can be mentioned. The organic solvent is used in an amount of usually 100 to 5,000 parts by weight, preferably 120 to 4,000 parts by weight, based on 100 parts by weight of the total of the components (A-1) and (A-2).

The acid catalyst used in the present invention includes organic acids and inorganic acids. 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, and gallic acid , Butyric acid, melitic acid, arachidonic acid, mykimic acid, 2-ethylhexanoic acid, oleic acid, stearic acid, linoleic acid, linoleic acid, salicylic acid,
Benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, benzenesulfonic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, tartaric acid And a hydrolyzate of maleic anhydride. Examples of the inorganic acid include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, phosphoric acid and the like. Among these, organic acids can be mentioned as more preferred examples, and particularly preferred are hydrolysates of acetic acid, oxalic acid, maleic acid, formic acid, malonic acid and maleic anhydride. These are 1
Species or two types may be used simultaneously. The amount of the acid catalyst to be used is generally 0.00001 to 10 parts by weight, based on 100 parts by weight of the total amount of the components (A-1) and (A-2) (each in terms of complete hydrolysis condensate). Preferably it is in the range of 0.0001 to 7 parts by weight. If the use ratio of the acid catalyst is less than 0.00001 part by weight, the coatability of the coating film becomes poor, and if it exceeds 10 parts by weight, the storage stability of the solution may deteriorate. When the component (A-1) and the component (A-2) are hydrolyzed and condensed, (A-
It is preferable to use 0.25 to 3 moles of water, and 0.3 to 2.5 moles of water per mole of the group represented by R ² O— contained in the component 1) and the component (A-2). It is particularly preferred to add. When the amount of water to be added falls within the range of 0.25 to 3 mol, there is no possibility that the uniformity of the coating film is reduced, and the storage stability of the film-forming composition is less likely to be reduced. That's why. Further, the water is preferably added intermittently or continuously. The acid catalyst may be added to the solvent together with the component (A-1) and the component (A-2), or may be added to water. In the present invention, (A
The temperature at which the component -1) and the component (A-2) are hydrolyzed is generally 0 to 100C, preferably 15 to 80C. In the present invention, the term “hydrolysis” does not require that all of the R ² O— groups contained in the above-mentioned components (A-1) and (A-2) are hydrolyzed. , Two or more are hydrolyzed, or a mixture thereof.
In the present invention, the term "condensation" refers to the component (A-1) and the component (A-
2) Silanol groups of the hydrolyzate of the component condense to form Si-
In the present invention, all of the silanol groups need not be condensed, but a mixture of those having a small amount of silanol groups condensed, those having different degrees of condensation, etc. Is also included. In addition, the weight average molecular weight of the hydrolysis-condensation product of the component (A) is usually about 1,000 to 120,000, preferably about 1,200 to 100,000.

(B) Component The propylene glycol monoalkyl ether (B) used in the present invention includes propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monoisopropyl ether, and propylene glycol monobutyl ether. Can be mentioned,
Particularly preferred are propylene glycol monomethyl ether, propylene glycol monoethyl ether and propylene glycol monopropyl ether. These may be used alone or in combination of two or more. These may be used alone or in combination of two or more. In the present invention, the propylene glycol monoalkyl ether includes a compound represented by the following general formula (3) and a compound represented by the following general formula (4). R ³ OCH ₂ CHCH ₃ OH (3) R ³ OCHCH ₃ CH ₂ OH (4) (In the general formulas (3) and (4), R ³ has 1 to 1 carbon atoms. 4
Represents an alkyl group. In the present invention, the compound represented by the general formula (4) is 10% by weight or less of the total amount of the compound represented by the general formula (3) and the compound represented by the general formula (4). Is preferred. In the present invention, the content of the organic solvent other than propylene glycol monoalkyl ether in the composition for forming a layer film is 50% by weight or less.
In the present invention, when the component (B) is used as a solvent during the synthesis of the component (A), the reaction solution can be used as it is, but when a solvent other than the component (B) is used, the solvent It is necessary to replace the solvent so that 50% by weight or more of the solvent becomes the component (B).

Component (C) Compounds having a polyalkylene oxide structure that can be used in the present invention include a polymethylene oxide structure, a polyethylene oxide structure, a polypropylene oxide structure, a polytetramethylene oxide structure,
And a polybutylene oxide structure. Specifically, polyoxymethylene alkyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, ethylene oxide derivative of alkylphenol formalin condensate,
Ether type compounds such as polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene fatty acid alkanolamide Ether ester type compounds such as sulfates,
Polyethylene glycol fatty acid ester, ethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester,
Ether ester type compounds such as propylene glycol fatty acid ester and sucrose fatty acid ester can be exemplified.

Examples of the polyoxyethylene / polyoxypropylene block copolymer include compounds having the following block structures. - a (A) n- (B) m- (A) l- ( In the formula, A group represented by -CH ₂ CH ₂ O-, the B - (A) n- (B ) m- -
A group represented by CH ₂ CH (CH ₃ ) O—, wherein n is 1 to
90, m is a number from 10 to 99, and l is a number from 0 to 90) Among these, polyoxyethylene alkyl ether,
Polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester,
And ether-type compounds such as those described above as more preferable examples. These may be used alone or in combination of two or more.

In the present invention, the proportion of the component (C) used in the composition for forming a film is from 2 to 12 parts by weight of the component (C) based on 100 parts by weight of the component (A) (in terms of complete hydrolysis and condensate).
0 parts by weight, more preferably 4 to 100 parts by weight. When the amount of the component (C) is less than 2 parts by weight, the effect of lowering the relative dielectric constant of the coating film is small, and when it exceeds 120 parts by weight, the mechanical strength of the coating film decreases.

(D) Component In the present invention, the composition for forming a film preferably contains a surfactant. Examples of the surfactant include a nonionic surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and the like, and further, a fluorine-based surfactant, a silicone-based surfactant, Examples thereof include a polyalkylene oxide-based surfactant and a poly (meth) acrylate-based surfactant, and preferably include a fluorine-based surfactant and a silicone-based surfactant.

As the fluorine-based surfactant, for example, 1,
1,2,2-tetrafluorooctyl (1,1,2,2-
Tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctylhexyl ether, octaethylene glycol di (1,1,2,2-tetrafluorobutyl)
Ether, hexaethylene glycol (1, 1, 2,
2,3,3-hexafluoropentyl) ether, octapropylene glycol di (1,1,2,2-tetrafluorobutyl) ether, hexapropylene glycol di (1,1,2,2,3,3-hexafluoro) Pentyl) ether, sodium perfluorododecyl sulfonate,
1,1,2,2,8,8,9,9,10,10-decafluorododecane, 1,1,2,2,3,3-hexafluorodecane, N- [3- (perfluorooctanesulfone Amido) propyl] -N, N′-dimethyl-N-carboxymethyleneammonium betaine, perfluoroalkylsulfonamidopropyltrimethylammonium salt,
At least one of terminal, main chain and side chain of perfluoroalkyl-N-ethylsulfonylglycine salt, bis (N-perfluorooctylsulfonyl-N-ethylaminoethyl) phosphate, monoperfluoroalkylethyl phosphate, etc. And a fluorine-based surfactant composed of a compound having a fluoroalkyl or fluoroalkylene group at the position (1). Commercially available products are MegaFac F142D, F172, F173, F1
83 (manufactured by Dainippon Ink and Chemicals, Inc.), F-Top EF301, 303, and 352 (manufactured by Shin-Akita Chemical Co., Ltd.), Florad FC-430, and FC-431
(Manufactured by Sumitomo 3M Limited), Asahi Guard AG71
0, Surflon S-382, SC-101, SC-
102, SC-103, SC-104, SC-1
05, SC-106 (manufactured by Asahi Glass Co., Ltd.), BM-10
00, BM-1100 (manufactured by Yusho Co., Ltd.), NBX-15
(Neos Co., Ltd.) and other commercially available fluorosurfactants. Among them, the above MegaFac F172, BM-1000, BM-11
00, NBX-15 is particularly preferred.

Examples of the silicone-based surfactant include SH7PA, SH21PA, SH30PA, and ST94P.
A (All are Dow Corning Toray Silicone Co., Ltd.)
And the like can be used. Among them, the above S
The following general formula (5) corresponding to H28PA, SH30PA
The polymer represented by is particularly preferable.

[0022]

Embedded image (Wherein, R12 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n represents in integer der (equation 1 to 20, R ¹³ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n is 1
And x and y are each independently 2 to 10
It is an integer of 0. The amount of the surfactant to be used is generally 0.0001 to 10 parts by weight based on 100 parts by weight of the component (A) (completely hydrolyzed condensate).

In the present invention, the content of the alcohol having a boiling point of 100 ° C. or less in the composition for film formation is 20% by weight or less,
In particular, it is preferably at most 5% by weight. Boiling point 100 ° C
The following alcohols are used as the component (A-1) and the component (A).
-2) It may occur during hydrolysis and / or condensation of the component, and it is preferable to remove the component by distillation or the like so that the content is 20% by weight or less, preferably 5% by weight or less. The total solid concentration of the film-forming composition of the present invention is preferably 2 to 30% by weight, and is appropriately adjusted depending on the purpose of use. When the total solid content of the composition is 2 to 30
When it is% by weight, the thickness of the coating film is in an appropriate range, and the storage stability is more excellent.

The film-forming composition of the present invention may further contain the following components. Other Additives Components such as colloidal silica, colloidal alumina, an organic polymer, and a surfactant may be further added to the film-forming composition obtained in the present invention. Colloidal silica is, for example, a dispersion in which high-purity silicic anhydride is dispersed in the hydrophilic organic solvent, and usually has an average particle size of 5 to 30 m.
μ, preferably 10-20 μm, solid content concentration of 10-4
It is about 0% by weight. Examples of such colloidal silica include methanol silica sol and isopropanol silica sol manufactured by Nissan Chemical Industry Co., Ltd .; and Oscar manufactured by Catalyst Chemicals Co., Ltd. Examples of the colloidal alumina include alumina sols 520, 100, and 200 manufactured by Nissan Chemical Industries, Ltd .; and alumina clear sol, alumina sol 10, and 132 manufactured by Kawaken Fine Chemicals Co., Ltd. Examples of the organic polymer include a compound having a sugar chain structure, a vinylamide polymer, a (meth) acrylic polymer, an aromatic vinyl compound, a dendrimer, a polyimide, a polyamic acid, a polyarylene, a polyamide, a polyquinoxaline, and a polyoxadiene. An azole, a fluoropolymer and the like can be mentioned.

[0025] The composition of the present invention is applied to a silicon wafer, Si
When applying to a substrate such as an O2 wafer or a SiN wafer, a coating method such as spin coating, dipping, roll coating, or spraying is used.

In this case, the film thickness may be about 0.05 to 1.5 μm in a single coating, and about 0.1 to 3 μm in a double coating. it can. Thereafter, by drying at room temperature or by heating at a temperature of about 80 to 600 ° C., usually for about 5 to 240 minutes, a glassy or macromolecular insulating film can be formed. As a heating method when forming the film,
A hot plate, an oven, a furnace, or the like can be used, and the heating can be performed under air, a nitrogen atmosphere, an argon atmosphere, a vacuum, a reduced pressure with controlled oxygen concentration, or the like.

The interlayer insulating film thus obtained is excellent in insulation, uniformity of coating film, dielectric constant, and low hygroscopicity of coating film.
M, SDRAM, RDRAM, D-RDRAM, etc., interlayer insulating films for semiconductor devices, protective films such as surface coat films for semiconductor devices, interlayer insulating films for multilayer wiring boards, protective films and insulating films for liquid crystal display devices, etc. Useful for applications.

[0028]

The present invention will now be described more specifically with reference to examples. Parts and% in Examples and Comparative Examples are parts by weight and% by weight, respectively, unless otherwise specified. Further, the evaluation of the film-forming composition in the examples was measured as follows.

The weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC) under the following conditions. Sample: Prepared by dissolving 1 g of a hydrolyzed condensate in 100 cc of tetrahydrofuran using tetrahydrofuran as a solvent. Standard polystyrene: Standard polystyrene manufactured by Pressure Chemical Co., USA was used. Apparatus: High-temperature, high-speed gel permeation chromatogram (model 150-C ALC / GPC) manufactured by Waters, Inc. Column: SHOdex A-80M manufactured by Showa Denko KK
(Length 50cm) Measurement temperature: 40 ° C Flow rate: 1cc / min

The composition for forming a uniform film thickness was applied on an 8-inch silicon wafer using a spin coater under the conditions of a rotation speed of 2,500 rpm and 30 seconds. Thereafter, using a hot plate maintained at a temperature of 90 ° C., the silicon wafer coated with the film-forming composition was heated for 3 minutes to disperse the organic solvent.
Next, using a hot plate maintained at a temperature of 200 ° C. in a nitrogen atmosphere, the silicon wafer coated with the film-forming composition was heated for 3 minutes to form a coating film on the silicon wafer. The film thickness of the coating film thus obtained was measured at 50 points in the coating film surface using an optical film thickness meter (Spectra Laser 200, manufactured by Rudolph Technologies). Calculate 3σ of the obtained film thickness,
Evaluation was made according to the following criteria. ；: 3σ of the coating film is within 2.5% of the average thickness of the coating film ×: 3σ of the coating film exceeds 2.5% of the average thickness of the coating film

Long-term storage stability The film-forming composition stored at 20 ° C. for 60 days was coated on an 8-inch silicon wafer using a spin coater under the conditions of a rotation speed of 2,500 rpm and 30 seconds. Then, using a hot plate held at a temperature of 90 ° C.,
The silicon wafer coated with the film-forming composition was heated for 3 minutes to disperse the organic solvent. Next, a nitrogen atmosphere 200
The silicon wafer coated with the film-forming composition was heated for 3 minutes using a hot plate maintained at a temperature of ° C. to form a coating film on the silicon wafer. The film thickness of the coating film thus obtained is measured by an optical film thickness meter (Rudolph T).
Spectra Las, manufactured by technologies
er200) at 50 points in the coating film plane. The film thickness of the obtained film thickness was measured, and the storage stability was evaluated based on the film thickness increase rate determined by the following equation. Film thickness increase rate (%) = ((film thickness after storage) − (film thickness before storage)) ÷ (film thickness before storage) × 100 {}: film thickness increase rate 5% or less ×: film thickness increase rate More than 5%

[0032] On the dielectric constant 8-inch silicon wafer, and applying the composition sample by spin coating, 3 minutes at 90 ° C. on a hot plate for 3 minutes substrates in the vapor 200 ° C. and dried in nitrogen Prefecture, further 6 in a vacuum oven at 420 ° C. under reduced pressure (50 mTorr).
The substrate was baked for 0 minutes. Aluminum was vapor-deposited on the obtained substrate to produce a substrate for permittivity evaluation. Dielectric constant is HP16451B manufactured by Yokogawa / Hewlett-Packard Co., Ltd.
It was calculated from the capacitance value at 10 kHz using an electrode and an HP4284A Precision LCR meter.

The elastic of 8-inch silicon wafer, and applying the composition sample by spin coating, 3 minutes at 90 ° C. on a hot plate for 3 minutes substrates in the vapor 200 ° C. and dried in nitrogen Prefecture, further 6 in a vacuum oven at 420 ° C. under reduced pressure (50 mTorr).
The substrate was baked for 0 minutes. The modulus of elasticity of the obtained film was measured using a nano indenter XP (manufactured by Nano Instruments).
It was measured by a continuous stiffness measurement method.

Synthesis Example 1 In a quartz separable flask, 178.42 g of methyltrimethoxysilane and 55.68 of tetramethoxysilane were used.
g of propylene glycol monoethyl ether 290
g, then stirred with a three-one motor,
The solution temperature was stabilized at 60 ° C. Next, maleic acid 0.1.
146 g of ion-exchanged water in which 11 g was dissolved was added to the solution over 1 hour. Then, after reacting at 60 ° C. for 2 hours, the reaction solution was cooled to room temperature. 270 g of propylene glycol monoethyl ether was added to this solution, and 5
270 g of a solution containing methanol and water from the reaction solution at 0 ° C.
Removal was performed by evaporation to obtain a reaction solution. The weight average molecular weight of the condensate and the like thus obtained is 2,90.
It was 0.

Synthesis Example 2 A reaction liquid was obtained in the same manner as in Synthesis Example 1 except that propylene glycol monomethyl ether was used instead of propylene glycol monoethyl ether. The weight average molecular weight of the condensate and the like thus obtained was 2,950.

Synthesis Example 3 In a quartz separable flask, 144.96 g of methyltrimethoxysilane and 102.3 of tetraethoxysilane were used.
3 g of propylene glycol monopropyl ether 2
After dissolving in 90 g, the mixture was stirred with a three-one motor, and the solution temperature was stabilized at 60 ° C. Next, 146 g of ion-exchanged water in which 0.05 g of maleic acid was dissolved was added to the solution over 1 hour. Then, after reacting at 60 ° C. for 2 hours, the reaction solution was cooled to room temperature. 270 g of propylene glycol monopropyl ether was added to this solution, and at 50 ° C., 270 g of a solution containing methanol, ethanol and water was removed from the reaction solution by evaporation to obtain a reaction solution. The weight average molecular weight of the condensate and the like thus obtained was 2,500.

Comparative Synthesis Example 1 A reaction solution was obtained in the same manner as in Synthesis Example 1 except that methyl ethyl ketone was used instead of propylene glycol monoethyl ether. The weight average molecular weight of the condensate and the like thus obtained was 1,250.

Example 1 A molecular weight of 2,000 was added to 50 g of the reaction solution obtained in Synthesis Example 1.
1.1 g of polyethylene oxide and NBX-15
0.003 g was dissolved and filtered through a Teflon filter having a pore size of 0.2 μm to obtain a film-forming composition of the present invention.
The obtained composition was applied on a silicon wafer by a spin coating method. The thickness of the obtained coating film is 530.7 nm.
And 3σ was as good as 1.7%. When the storage stability of the solution was evaluated, the film growth rate after 60 days was 3.8%, indicating excellent storage stability. When the relative dielectric constant of the coating film was evaluated, it showed a low dielectric constant of 2.48. Furthermore, when the elastic modulus of the coating film was evaluated, it was a high value of 5.2 GPa.

Example 2 A polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer (Newpol PE6, manufactured by Sanyo Chemical Co., Ltd.) was added to 50 g of the reaction solution obtained in Synthesis Example 2.
1 _{[HO-PEO 2 -PPO 70 -PEO 2} -OH equivalent])
3.3 g and 0.003 g of SH28PA were dissolved.
Filtration was performed with a Teflon filter having a pore diameter of 2 μm to obtain a film-forming composition of the present invention. The obtained composition was applied on a silicon wafer by a spin coating method. The thickness of the obtained coating film was 480.7 nm, and 3σ was as good as 1.9%. When the storage stability of the solution was evaluated,
The film increase rate after 4.2 days was 4.2%, indicating excellent storage stability.
Further, when the relative dielectric constant of the coating film was evaluated, it showed a low dielectric constant of 2.28. Furthermore, when the elastic modulus of the coating film was evaluated, it was a high value of 4.2 GPa.

Example 3 A polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer (Newpole PE6 manufactured by Sanyo Chemical Co., Ltd.) was added to 50 g of the reaction solution obtained in Synthesis Example 3.
1 _{[HO-PEO 2 -PPO 70 -PEO 2} -OH equivalent])
3.9 g and 0.003 g of SH28PA were dissolved.
Filtration was performed with a Teflon filter having a pore diameter of 2 μm to obtain a film-forming composition of the present invention. The obtained composition was applied on a silicon wafer by a spin coating method. The thickness of the obtained coating film was 450.7 nm, and 3σ was as good as 2.0%. When the storage stability of the solution was evaluated,
The film growth rate after 4.5 days was 4.5%, indicating excellent storage stability.
When the relative permittivity of the coating film was evaluated, it showed a low permittivity of 1.98. Furthermore, when the elastic modulus of the coating film was evaluated, it was 3.2 GPa, which was a very high value for a very low relative dielectric constant.

Comparative Example 1 Evaluation was performed in the same manner as in Example 1 except that only the reaction solution obtained in Synthesis Example 1 was used. The dielectric constant of the obtained coating film was 2.73, and a coating film having a dielectric constant of 2.5 or less was not obtained.

[0042]

According to the present invention, a hydrolyzate of an alkoxysilane and / or a condensate thereof is produced with an acid catalyst and water to contain a propylene glycol monoalkyl ether and a compound having a polyalkylene oxide structure. It is intended to provide a film-forming composition (material for an interlayer insulating film) having an excellent balance of coating uniformity, long-term storage stability, a coating having a relative dielectric constant of 2.5 or less, and mechanical strength of the coating. It is possible.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Jun Shiota, Jae Suaru Co., Ltd., 2-11-24 Tsukiji, Chuo-ku, Tokyo (72) Inventor Kinji: Jae Suar, 11-11-24 Tsukiji, Chuo-ku, Tokyo F term (reference) 4J038 DF021 DF022 DL031 DL032 JA02 JA03 JA17 JA25 JA55 JC32 KA04 KA06 KA09 NA11 NA17 NA21 NA26 PB09 PC02 PC08

Claims (11)

[Claims] (A) (A-1) a compound represented by the following general formula (1): R ¹ _a Si (OR ² ) _4-a (1) (R ¹ is a hydrogen atom, A fluorine atom or a monovalent organic group, R ² represents a monovalent organic group, a represents an integer of 1 to 2) and (A-2) a compound represented by the following general formula (2) A hydrolyzate or a condensate obtained by reacting a compound comprising Si (OR ² ) ₄ (2) (R ² represents a monovalent organic group) with an acid catalyst in the presence of water; On the other hand, a film-forming composition comprising (B) a propylene glycol monoalkyl ether and (C) a compound having a polyalkylene oxide structure. 2. The component (A-1) is at least one selected from methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane and dimethyldiethoxysilane, and the component (A-2) is tetramethoxysilane and The composition for forming a film according to claim 1, wherein the composition is at least one selected from tetraethoxysilane. 3. The use ratio of the component (A-1) to the component (A-2) is based on 100 parts by weight of the component (A-1) (in terms of a completely hydrolyzed condensate). 2. The film-forming composition according to claim 1, wherein the amount of the component is 2 to 120 parts by weight (in terms of a completely hydrolyzed condensate). 4. The use ratio of the component (A-1) and the component (A-2) to the acid catalyst is as follows:
2) The composition for forming a film according to claim 1, wherein the acid catalyst is used in an amount of 0.00001 to 10 parts by weight based on 100 parts by weight of the total of components (complete hydrolyzed condensate). 5. The film-forming composition according to claim 1, wherein the acid catalyst is an organic acid. 6. The propylene glycol monoalkyl ether is at least one selected from propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monoisopropyl ether, and propylene glycol monobutyl ether. The composition for forming a film according to claim 1, wherein 7. The film-forming composition according to claim 1, wherein the propylene glycol monoalkyl ether contains a compound represented by the following general formula (3) and a compound represented by the following general formula (4). object. R ³ OCH ₂ CHCH ₃ OH (3) R ³ OCHCH ₃ CH ₂ OH (4) (In the general formulas (3) and (4), R ³ has 1 to 1 carbon atoms. 4
Represents an alkyl group. ) 8. The compound represented by the general formula (4) is not more than 10% by weight of the total amount of the compound represented by the general formula (3) and the compound represented by the general formula (4). The composition for forming a film according to claim 7, wherein: 9. The compound having a polyalkylene oxide structure is at least one selected from a polymethylene oxide structure, a polyethylene oxide structure, a polypropylene oxide structure, a polytetramethylene oxide structure, and a polybutylene oxide structure. The composition for forming a film according to claim 1. 10. The film-forming composition according to claim 1, further comprising (D) a fluorine-based surfactant and / or a silicone-based surfactant. 11. An insulating film forming material comprising the film forming composition according to claim 1. Description: