JP2003133306A - Method of forming interlayer insulating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method by which an interlayer insulating film, that is improved in dielectric property and is superior in balance of the adhesive property, etc., to a substrate can be manufactured as the interlayer insulating film of a semiconductor element, etc. SOLUTION: In this method, the interlayer insulating film is formed, by forming an applied film containing a specific silicon compound on the substrate and exposing the film to heat and/or optically treating the film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming an interlayer insulating film.

[0002]

2. Description of the Related Art A silicon oxide film is often used as an interlayer insulating film such as an electric insulating film or a dielectric film of a silicon device such as a semiconductor. Usually, these silicon oxide films are formed by a method of thermally oxidizing silicon in air, a method of forming silane gas or disilane gas by plasma CVD method in an oxidizing gas such as oxygen or nitric oxide, or a direct sputtering method from quartz. Dry processes such as method of forming by method have been applied. Recently, in order to form a more uniform interlayer insulating film, SOG (S
A coating type insulating film containing a hydrolysis product of tetraalkoxysilane as a main component, which is called a pinon glass film, has also been used. Further, with the high integration of semiconductor elements and the like, an interlayer insulating film having a low dielectric constant, which is mainly called polyorganosiloxane called organic SOG, has been developed.

However, with further higher integration and multi-layering of semiconductor elements and the like, more excellent electrical insulation between conductors is required, and an interlayer insulating film material having a lower dielectric constant is required. Therefore, various new materials have been studied. For example, in JP-A-6-181201, an organometallic compound containing at least one element selected from titanium, zirconium, niobium, and tantalum, and an organosilicon compound having at least one alkoxy group in the molecule are polycondensed. It is disclosed that an interlayer insulating film having a lower dielectric constant can be obtained by using the composition containing an oligomer having a number average molecular weight of 500 or more as a main component. In addition, WO96 / 00758 discloses an insulating film forming material composed of alkoxysilanes, metal alkoxides other than silane, organic solvents and the like. Further, JP-A-3-20377 discloses a composition for forming an interlayer insulating film, which contains a component obtained by hydrolyzing a specific silane compound and a specific chelate compound in the presence of an organic solvent and polymerizing the compound. Has been done. However, the conventionally known interlayer insulating film materials have a problem that the coating film is not sufficiently uniform and the balance between the dielectric constant and the adhesion is also problematic.

[0004]

The present invention relates to a method of forming an insulating film for solving the above problems, and more specifically, as an interlayer insulating film in a semiconductor device or the like, it improves the dielectric characteristics and adheres to a base. It is an object of the present invention to provide a method for forming an interlayer insulating film which is excellent in balance of properties and the like.
Other objects and advantages of the present invention will be apparent from the following description.

[0005]

According to the present invention, the above objects and advantages of the present invention are as follows. First, on a substrate, (A) Formula Si _n R _m (where n is an integer of 3 or more) is used. And m is n
To (2n + 2) and m R independently of one another are a hydrogen atom, an alkyl group, a phenyl group or a halogen. However, when all of m Rs are hydrogen atoms and m = 2n, n is an integer of 7 or more. ), And a polysilane compound (B)
An interlayer characterized by forming a coating film containing at least one silicon compound selected from the group consisting of cyclopentasilane, cyclohexasilane, and silylcyclopentasilane, followed by heat and / or light treatment. This is achieved by the method of forming an insulating film (hereinafter referred to as the first method). According to the present invention, the above-mentioned objects and advantages of the present invention are secondly provided on a substrate by the formula (A ′) Si _i H
_{2i + 2} (where i is an integer of 2 to 8), a hydrogenated chain silane compound represented by the formula Si _j H _2j (where j is an integer of 3 to 10). Hydrogenated cyclic silane compound and Si _k H _k (where k is 6
It is an integer of -10. (B) Cyclopentasilane, cyclohexasilane, and silylcyclopentasilane, which are produced by irradiation of at least one silane compound selected from the group consisting of hydrogenated cage silane compounds represented by A method for forming an interlayer insulating film, which comprises forming a coating film containing at least one silicon compound selected from the group consisting of, and then performing heat and / or light treatment (hereinafter referred to as a second method). )
Achieved by

According to the present invention, thirdly, the above objects and advantages of the present invention are as follows: on a substrate, the formula (A ") Si _n R _m (where n is an integer of 3 or more, and m is n- (2n + 2)
Represents a hydrogen atom, an alkyl group, a phenyl group or a halogen independently of each other).
And a reaction product of the compound represented by the formula (C) with a compound selected from the group consisting of an organic hydroxy compound and an organic carboxylic acid, followed by heat and / or light treatment. It is achieved by the method of forming an interlayer insulating film (hereinafter, referred to as a third method). According to the present invention, the above objects and advantages of the present invention are
Fourth, on the substrate, the (A ″) formula Si _n R _m (where n
Represents an integer of 3 or more, m represents an integer of n to (2n + 2), and a plurality of Rs independently represent a hydrogen atom, an alkyl group, a phenyl group or a halogen), and (C) A method for forming an interlayer insulating film, which comprises forming a coating film containing a mixture of an organic hydroxy compound and a compound selected from the group consisting of organic carboxylic acids, and then subjecting it to heat and / or light treatment. (Hereinafter, referred to as the fourth method).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below. First, the first method and the second method will be described, and then the third method and the fourth method will be described.
In the above formula representing the polysilane compound (A), examples of the alkyl group represented by R include a methyl group, an ethyl group, and n.
-Propyl group, i-propyl group, n-butyl group, sec
-Butyl group, t-butyl group, n-pentyl group, i-pentyl group, neopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, n-octyl group, n-nonyl group and n-decyl group, etc. The alkyl group having 1 to 10 carbon atoms can be mentioned as a preferable example. Further, as the halogen atom, for example, fluorine, chlorine and bromine can be mentioned as preferable ones. The polysilane compound may have a chain shape, a ring shape, or a cage shape. Among the above polysilane compounds, hydrogenated polysilane compounds in which all R are hydrogen atoms are preferably used. As such a hydrogenated polysilane compound, a compound represented by the formula S
i _n H _{2n +} hydrogenated chain polysilane represented by _2, wherein S
i _n hydrogenated cyclic polysilane represented by H _2n, and hydrogenated cage-like polysilane compound represented by the formula Si _n H _n is preferably used. In addition, "cage-like" means a thing including a Prisman skeleton, a Cuban skeleton, a pentagonal prism skeleton, and the like. However, n in each of the above formulas is 3 to 100,000, preferably 5 to 5 in the hydrogenated chain polysilane.
It is an integer of 50,000 and is 7 to 100,000, preferably 8 to 50,000 in hydrogenated cyclic polysilane.
And in hydrogenated cage polysilanes from 6 to 100,000, preferably from 7 to 50,000. In this case, when n is smaller than the above-mentioned minimum value, there may be a problem in film-forming property of the polysilane compound, and when n is larger than the above-mentioned maximum value, the solubility due to the cohesive force of the polysilane compound may be caused. May be observed. Such polysilane compounds can be used alone or in admixture of two or more.

The polysilane compound used in the present invention can be produced, for example, by the following method using a monomer having a desired structural unit as a raw material. (A) A method of dehalogenating polycondensation of halosilanes in the presence of an alkali metal (so-called "kipping method", J. Am. Che
m. Soc. , 110 , 2342 (1988) and M.
acromolecules, 23 , 3423 (199
0)); (b) Method of dehalogenating polycondensation of halosilanes by electrode reduction (J. Chem. Soc., C.
hem. Commun. 1161 (1990) and J. Chem. Soc. Chem. Commun. ，
896 (1992)); (c) A method for dehydrogenative condensation polymerization of hydrosilanes in the presence of a metal catalyst (JP-A-4-26
No. 334551): (d) Method by anionic polymerization of disilene crosslinked with biphenyl or the like (Macr
o molecules, 23, 4494 (1990)
reference). (E) After synthesizing the cyclic silicon compound substituted with a phenyl group or an alkyl group by the above method, a known method (for example, Z. Anorg. Allg. Chem., 4
59 , 123-130 (1979), E.I. Henggg
e et al Mh. Chem. Volume 106, Pages 503, 197
It can be converted to a hydro-substituted product, a halogen-substituted product or the like after 5 years), and (f) the silane compound synthesized by the above method can be irradiated with light to obtain a higher molecular weight polysilane compound.

In the case (f) of synthesizing a polysilane compound by irradiating a silane compound with light, the silane compound as a raw material thereof is represented by the formula Si _i H _{2i + 2} (where i is 2 to 2).
It is an integer of 8, and preferably an integer of 2 to 4. ), A hydrogenated cyclic silane compound represented by the formula: Si _j H _2j (where j is an integer of 3 to 10, preferably an integer of 3 to 6) , And the formula Si _k H _k (where k is an integer from 6 to 10).
Hydrogenated cage silane compounds represented by are preferred. Of these, the hydrogenated cyclic silane compounds are more preferable, and at least one compound selected from the group consisting of cyclopentasilane, cyclohexasilane, and silylcyclopentasilane is particularly preferable. These are respectively represented by the following formulas (1) to (3).

[0010]

[Chemical 1]

These silane compounds can be produced via decaphenylcyclopentasilane and dodecaphenylcyclopentasilane produced from diphenyldichlorosilane. These silane compounds can be used alone or as a mixture of two or more kinds. When irradiating light, in addition to visible light, ultraviolet light, far ultraviolet light, low-pressure or high-pressure mercury lamp, deuterium lamp, discharge light of rare gas such as argon, krypton, xenon, YAG laser, argon laser, carbonic acid, etc. Gas laser, XeF, XeCl, XeBr, KrF, KrC
An excimer laser such as 1, ArF or ArCl may be used as a light source. As these light sources, those having an output of 10 to 5,000 W are preferably used. Usually 100 to 1,000 W is sufficient. The wavelength of these light sources is not particularly limited as long as it is absorbed by the silane compound in the composition or coating film to some extent.
70 nm to 600 nm is preferable. The temperature at which the light irradiation treatment is performed is preferably room temperature to 300 ° C. or lower. The processing time is about 0.1 to 30 minutes. The light irradiation treatment is preferably performed in a non-oxidizing atmosphere. Further, the light irradiation treatment may be carried out in the presence of a suitable solvent. As such a solvent, those similar to the solvent described below as an optional addition component of the composition of the present invention can be used.

The above polysilane compounds have the formula Si _n R _m
If the degree of polymerization n is about 10 or more, the solubility in a general-purpose solvent such as a hydrocarbon-based solvent or an ether-based solvent becomes significantly low and the polymer becomes substantially insoluble. It was practically impossible to form a film on it and convert it into a silicon oxide film. In the present invention, it was found that a specific liquid silane compound exhibits good solubility in such an originally solvent-insoluble polysilane compound, and the polysilane compound can be used as a raw material for a silicon oxide film. It was By using such a relatively high molecular weight polysilane compound as a raw material for the silicon oxide film, there is an advantage that the formed film becomes dense and excellent in uniformity and of high quality. The specific silane compound (B) used in the present invention is at least one silane compound selected from the group consisting of cyclopentasilane, cyclohexasilane and silylcyclopentasilane. In the present invention, these silane compounds can be used alone or as a mixture of two or more kinds.

The ratio of the polysilane compound to the silane compound constituting the solution composition of the present invention is preferably 0.01 to 1,000% by weight, more preferably 0.0.
It is 5 to 500% by weight, particularly preferably 0.1 to 100% by weight. If this value is less than 0.01% by weight, the coating film may be too thin after coating to finally form a continuous silicon oxide film. On the other hand, when this value exceeds 1,000% by weight, the polysilane compound may not be completely dissolved.

The composition of the present invention may further contain a solvent. The solvent used here is not particularly limited as long as it does not react with each component of the composition of the present invention described above. For example, n-pentane, n-hexane,
n-heptane, n-octane, decane, dicyclopentane, benzene, toluene, xylene, durene, indene, tetrahydronaphthalene, decahydronaphthalene,
Hydrocarbon solvents such as squalane; diethyl ether,
Dipropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether,
Tetrahydrofuran tetrahydropyran, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether,
Examples thereof include ether solvents such as p-dioxane and tetrahydrofuran; and polar solvents such as propylene carbonate, γ-butyrolactone, N-methyl-2-pyrrolidone, dimethylformamide, acetonitrile, dimethylsulfoxide, methylene chloride and chloroform. Of these, hydrocarbon solvents are preferable from the viewpoint of stability of the solution. These solvents may be used alone or in 2
It can also be used as a mixture of two or more species. When the above-mentioned solvent is used, the amount used can be appropriately adjusted according to the desired film thickness of the silicon oxide film. It is preferably 10,000% by weight or less, and particularly preferably 5,000% by weight or less, based on the above silane compound. 10,000
If it exceeds 5% by weight, a polysilane compound may precipitate, which is not preferable.

If necessary, a surfactant may be added to the composition of the present invention as long as the object and function of the present invention are not impaired. Such surfactants can be cationic, anionic, zwitterionic, or nonionic. Among these, nonionic surfactants improve the wettability of the composition to the object to be coated, improve the leveling property of the coated film, and prevent the occurrence of crushing of the coating film and the occurrence of orange peel skin. It can be preferably used because of its usefulness. Examples of such nonionic surfactants include fluorine-based surfactants having a fluorinated alkyl group or perfluoroalkyl group, or polyether alkyl-based surfactants having an oxyalkyl group.

Examples of the fluorine-containing surfactant include Ftop EF301, EF303, and EF352.
(Manufactured by Shin-Akita Kasei Co., Ltd.), Megafac F171, F
173 (manufactured by Dainippon Ink and Chemicals, Inc.), Asahi Guard AG7
10 (manufactured by Asahi Glass Co., Ltd.), Florard FC-170C,
FC430 and FC431 (Sumitomo 3M Limited)
Manufactured), Surflon S-382, SC101, SC1
02, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), BM-1000, SC1
100 (manufactured by BM Chemie), Schsego
-Fluor (manufactured by Schwegmann), C ₉ F ₁₉
CONHC ₁₂ H ₂₅ , C ₈ F ₁₇ SO ₂ NH- (C ₂ H ₄ O) ₆
H, C ₉ F ₁₇ O (Pluronic L-35) C ₉ F ₁₇ , C ₉
F ₁₇ O (Pluronic P-84) C ₉ F ₁₇ , C ₉ F ₁₇ O
(Tetronic-704) (C ₉ F ₁₇ ) _{2 and the} like can be mentioned. (Here, Pluronic L-35: Asahi Denka Kogyo KK, polyoxypropylene-polyoxyethylene block copolymer, average molecular weight 1,900; Pluronic P-84: Asahi Denka Kogyo KK, polyoxy Propylene-polyoxyethylene block copolymer, average molecular weight 4,200; Tetronic-704: Asahi Denka Co., Ltd., N, N, N ', N'-tetrakis (polyoxypropylene-polyoxyethylene block copolymer Polymer),
The average molecular weight is 5,000. )

As the polyether alkyl type surfactant, for example, polyoxyethylene alkyl ether,
Examples thereof include polyoxyethylene allyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, and oxyethyleneoxypropylene block polymer. Specific examples of these polyether alkyl-based surfactants include Emulgen 105, 430 and 81.
0, the same 920, Leodol SP-40S, the same TW-L1
20, Emanol 3199, Same 4110, Exel P-
40S, bridges 30, 52, 72, 92, Arassel 20, Emazol 320, Tween 20, 6
0, Merge 45 (all manufactured by Kao Corporation), Noniball 55 (manufactured by Sanyo Kasei Co., Ltd.) and the like.
Examples of nonionic surfactants other than the above include polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyalkylene oxide block copolymer, and the like. Specifically, Chemistat 2
500 (manufactured by Sanyo Chemical Industry Co., Ltd.), SN-EX9228
(Manufactured by San Nopco Co., Ltd.), Nonal 530 (manufactured by Toho Chemical Industry Co., Ltd.) and the like. The amount of such a surfactant used is preferably 10 parts by weight or less, particularly preferably 0.1 to 5 parts by weight, based on 100 parts by weight in total of the polysilane compound, the silane compound, and the solvent optionally added. It is a department. Here, if the amount exceeds 10 parts by weight, the composition obtained is likely to foam, and thermal discoloration may occur, which is not preferable.

Further, colloidal silica dispersed in a suitable dispersion medium may be added to the composition of the present invention.
This colloidal silica is used to increase the silicon concentration of the composition of the present invention, and the amount of this component used can also control the thickness of the resulting coating film. When colloidal silica is used, it is preferable to select and use a dispersion medium in consideration of compatibility with the silane compound used in the present invention and an organic solvent which is an optional additional component. As such a dispersion medium, the compounds exemplified as the solvent which is an optional addition component of the present invention can be used. Further, in the composition of the present invention, for the purpose of preventing gelation and thickening of the composition, heat resistance of the obtained silicon oxide film, chemical resistance, hardness, and improvement of adhesion, and further for preventing static electricity, Fine powders of metal oxides such as aluminum oxide, zirconium oxide, and titanium oxide can be appropriately mixed.

In the present invention, the above composition is applied onto a substrate by an appropriate method such as a spray method, a roll coating method, a curtain coating method, a spin coating method, a screen printing method, an offset printing method and an ink jet method. The coating is applied so that the film thickness is preferably 0.005 to 10 μm, more preferably 0.01 to 5 μm. In addition,
When the composition contains a solvent, the above film thickness should be understood as the film thickness after removal of the solvent. The film forming process is performed in a non-oxidizing atmosphere. In order to realize such an atmosphere, an atmosphere that does not substantially contain an oxidizing substance such as oxygen or carbon dioxide may be used. Specifically,
Atmospheres in nitrogen, hydrogen, noble gases and mixed gases thereof can be preferably used.

Further, in order to form a coating film of the composition of the present invention on a substrate with good adhesion and high density, it is preferable to perform light irradiation treatment at least once before and after coating. In such light irradiation treatment, in addition to visible light, ultraviolet light, far ultraviolet light, low-pressure or high-pressure mercury lamp, deuterium lamp, discharge light of rare gas such as argon, krypton, xenon, YAG laser, argon laser, etc. , Carbon dioxide laser, XeF, XeCl, XeB
An excimer laser such as r, KrF, KrCl, ArF, or ArCl can be used as a light source. As these light sources, those having an output of 10 to 5,000 W are preferably used. Usually 100 to 1,000 W is sufficient. The wavelength of these light sources is not particularly limited as long as the polysilane compound in the composition or the coating film absorbs even a little, but 170 nm to 600 nm is preferable.
The temperature during the light irradiation treatment is preferably room temperature to 300.
℃. The processing time is about 0.1 to 30 minutes. It is preferable that these light irradiation treatments are performed in a non-oxidizing atmosphere similar to the film forming step of the polysilane compound. It is presumed that such light irradiation treatment causes the cleavage of the silicon-silicon bond and the recombination reaction of the polysilane compound in the coating film, thereby improving the film physical properties such as adhesion to the substrate. It Further, it is considered that the silane compound in the coating film is subjected to ring-opening polymerization by light irradiation to become polysilane, and a more dense film is formed.

The coating film of the composition of the present invention formed as described above is then converted into a silicon oxide film by heat and / or light treatment in a suitable atmosphere.
The treatment method at this time preferably includes a heat treatment step. The silicon oxide film is formed by subjecting the coating film of the composition of the present invention formed as described above to heat treatment and / or light irradiation treatment in the presence of oxygen and / or ozone, for example, in air. . The heat treatment is preferably performed using a heating means such as a hot plate or an oven, preferably 100 to 1100 ° C., more preferably 200 to 900.
C., more preferably 300 to 800.degree. C., preferably 1 to 300 minutes, more preferably 5 to 120 minutes, still more preferably 10 to 60 minutes. Processing temperature is 10
If it is lower than 0 ° C, the oxidation reaction may be insufficient, while if the treatment temperature is higher than 1100 ° C, cracks may occur in the film after oxidation, which is not preferable. If the treatment time is shorter than 1 minute, the oxidation reaction may be insufficient, while it is not necessary to perform the heat treatment for a long time exceeding 300 minutes.

The silicon oxide film formed in the present invention may contain impurities such as carbon in addition to silicon oxide within the range not impairing the object of the present invention. The film thickness of the silicon oxide film which is the interlayer insulating film obtained in the present invention is preferably 0.01 to 20 μm, more preferably about 0.02 to 10 μm. The substrate used for forming the interlayer insulating film of the present invention is not particularly limited. The surface on which the coating film is formed may be a flat surface or a non-planar surface having steps, and the form thereof is not particularly limited. In the present invention, the interlayer insulating film is formed as described above. Further, when the polysilane compound coating film is irradiated with light, if a part of the coating film is selectively irradiated with light by using a photomask having a desired pattern, etc. Can also be formed.

Next, the third method and the fourth method of the present invention will be described. It should be understood that the matters not described here regarding the third method and the fourth method apply the same as those described above regarding the first method and the second method as they are or with obvious modifications to those skilled in the art. The component (A ″) is represented by the formula Si _n R _m (where n is an integer of 3 or more, m is an integer of n to (2n + 2), and a plurality of R are independently of each other a hydrogen atom. Represents an alkyl group, a phenyl group or halogen). Examples of the alkyl group include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, i-pentyl group, neopentyl group. , N-hexyl group, cyclohexyl group, n-heptyl group, n-octyl group, n-nonyl group and n-decyl group, etc.
Ten alkyl groups may be mentioned as preferred.

The polysilane compound may be chain-shaped, cyclic, or cage-shaped. From the viewpoint of thermodynamic stability of the polysilane compound, easiness of purification, and solubility in a solvent described later, a polysilane compound having n of about 3 to 50 is preferable. More preferably, the formula _Si n H
Hydrogenated chain polysilane represented by _{2n + 2} , formula Si _n H
A hydrogenated cyclic polysilane represented by _2n , and a formula Si _n
A hydrogenated cage polysilane compound represented by H _n is preferably used, and a hydrogenated cyclic polysilane represented by the formula Si _n H _{2 n} is particularly preferable. In addition, "cage-like" means a thing including a Prisman skeleton, a Cuban skeleton, a pentagonal prism skeleton, and the like. However, n in each of the above formulas is 3 in the case of hydrogenated chain polysilane and hydrogenated cyclic polysilane.
It is an integer of -50, preferably an integer of 3-12, and in the case of hydrogenated cage polysilane, an integer of 6-50, preferably an integer of 6-12. In this case, if it is smaller than the above-mentioned minimum value, a problem may occur in the film-forming property of the polysilane compound, and if n is larger than the above-mentioned maximum value, the decrease in the solubility due to the cohesive force of the polysilane compound may occur. This may be observed, narrowing the choice of solvent used. Particularly preferred polysilane compounds are cyclopentasilane, cyclohexasilane, and silylcyclopentasilane. Such polysilane compounds may be used alone or in combination of two or more.

The polysilane compound used in the present invention is a monomer having a desired structural unit as a raw material. For example, the first method and the second method are described as the production method of the polysilane compound in (a) to (c). It can be produced by the same method. The component (C) is an organic hydroxy compound and an organic carboxylic acid. These can be used alone or in combination of two or more. Preferred examples of the organic hydroxy compound include monoalcohols, dialcohols, trihydric or higher polyhydric alcohols, and phenols.

Examples of the monoalcohol include methanol, ethanol, propanol, isopropanol, butanol, tert-butanol, hexanol, cyclohexanol, octanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether,
Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoethyl ether Mention may be made of butyl ether, trimethylene glycol monomethyl ether, trimethylene glycol monoethyl ether, trimethylene glycol mono-n-propyl ether, trimethylene glycol monoisopropyl ether, glycerol dimethyl ether and glycerol diethyl ether. Among these, propylene glycol monoalkyl ether and dipropylene glycol monoalkyl ether have isomers, but any isomer or isomer mixture can be used.

Examples of dialcohols include ethylene glycol, propylene glycol, butanediol, heptanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, diethylene glycol, bistrimethylene glycol, glycerol monomethyl ether, glycerol monoethyl ether. And hydroquinone. Examples of the trihydric or higher polyhydric alcohol include glycerol. Examples of phenols include phenol, methylphenol, dimethylphenol, trimethylphenol, ethylphenol,
Mention may be made of diethylphenol and triethylphenol.

Examples of organic carboxylic acids include formic acid, acetic acid, lactic acid, oxalic acid, fumaric acid, maleic acid, itaconic acid, acrylic acid, succinic acid, and benzoic acid. Of these, monoalcohols are preferred, and propylene glycol monomethyl ether, propylene glycol monoisopropyl ether and trimethylene glycol monoisopropyl ether are more preferred.

The reaction between the above components (A '') and (C) is
The component (C) is preferably 0.01 to 1,000 parts by weight, more preferably 0.1 to 5 parts by weight, per 1 part by weight of the component (A '').
00 parts by weight, more preferably 1 to 300 parts by weight, and particularly preferably 3 to 100 parts by weight. The component (A ″) may be exposed before the reaction between the component (A ″) and the component (C). The conditions of the exposure process are the same as the conditions described later for the method of forming the silicon oxide film. The reaction temperature is preferably 0 to 150 ° C, more preferably 10 to 70 ° C, further preferably 20 to 50 ° C.
℃. By mixing the components (A ″) and (C) as described above, the Si—R bond (where R is the same as above) in the component (A ″), preferably the Si—H bond, is formed. It is presumed that all or part of the cleavage occurs and the alkoxyl group or carboxylate group derived from the component (C) forms a new bond with the Si atom. Here, when the component (C) contains a compound having two or more hydroxyl groups and / or carboxylic acid groups in one molecule, (C)
The component may form a bond with two or more molecules of the (A ″) component.

The above reaction can be carried out in the presence of a solvent, if necessary. Examples of the solvent used here include n-pentane, n-hexane, n-heptane, n-octane, decane, cyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, benzene, toluene, xylene, durene, indene, Tetrahydronaphthalene, decahydronaphthalene,
Hydrocarbon solvents such as squalane; diethyl ether,
Dipropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether,
Tetrahydrofuran tetrahydropyran, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether,
Examples thereof include ether solvents such as p-dioxane and tetrahydrofuran; and polar solvents such as propylene carbonate, γ-butyrolactone, N-methyl-2-pyrrolidone, dimethylformamide, acetonitrile, dimethylsulfoxide, methylene chloride and chloroform. These solvents may be used alone or in admixture of two or more. When a solvent is used in the above reaction, the amount of the solvent used is preferably 100,000 parts by weight or less, more preferably 50 to 50,000 parts by weight, and further preferably 2 parts by weight per 100 parts by weight of the component (A '').
It is from 00 to 10,000 parts by weight.

In the present invention, the reaction products of the above components (A ″) and (C) are usually used as a composition dissolved in a solvent. When the reaction between the component (A ″) and the component (C) is carried out in the presence of an excess of the component (C), the reaction mixture can be used as it is as the composition of the present invention. Further, when the reaction of the components (A ″) and (C) is carried out in the presence of a solvent, the reaction mixture can be used as it is as the composition of the present invention. Also,
When the reaction of the component (A ″) and the component (C) is carried out in the presence or absence of a solvent, a solvent may be further added to the reaction product to obtain the composition of the present invention. As the solvent that can be used here, the same solvents as those exemplified as the solvent that can be used in the reaction of the component (A ″) and the component (C) can be used. These solvents can be used alone or as a mixture of two or more kinds. The concentrations of the reaction products of the components (A ″) and (C) in the composition of the present invention as described above can be appropriately adjusted depending on the desired film thickness of the silicon oxide film. (A '')
The component concentration is preferably 1 to 50% by weight,
It is particularly preferably 5 to 30% by weight. In the present invention,
Similar to the reaction product of the component (A '') and the component (c),
A mixture of the component (A '') and the component (C) can be used.

According to the method of the present invention, it is possible to form an interlayer insulating film having a low dielectric constant and excellent adhesion to a substrate regardless of the area and shape of the substrate, and to obtain a device requiring high reliability. It can be preferably used for manufacturing. Further, the method of the present invention is low in cost because an expensive device such as a vacuum device is unnecessary.

[0033]

EXAMPLES The present invention will be described in more detail below with reference to examples. The invention is in no way limited by these examples.

Synthesis Example 1 (1) After replacing the inside of a 4-necked flask having a volume of 3 L equipped with a thermometer, a cooling condenser, a dropping funnel and a stirrer with argon gas, 1 L of dried tetrahydrofuran and lithium metal 18. 3 g was charged and bubbled with argon gas. While stirring the suspension at 0 ° C., 333 g of diphenyldichlorosilane was added from a dropping funnel, and after the dropping was completed, stirring was continued for 12 hours at room temperature until the lithium metal completely disappeared. Reaction mixture 5
It was poured into L ice water to precipitate the reaction product. This precipitate was separated by filtration, washed well with water, washed with cyclohexane, and vacuum dried to obtain 140 g of a white solid.
100 g of this white solid and 100 of dry cyclohexane
Charge 0 ml into a 2 L flask and add aluminum chloride 4
g was added, hydrogen chloride was introduced at room temperature, and the reaction was continued for 5 hours under an argon atmosphere. Here, separately, 40 g of lithium aluminum hydride and 400 ml of diethyl ether were charged into a 3 L flask, and the above reaction mixture was added with stirring at 0 ° C. under an argon atmosphere, followed by stirring at the same temperature for 1 hour and further at room temperature for 12 hours. Stirring was continued. After removing the aluminum compound from the reaction mixture, vacuum distillation was performed at 70 ° C. and 10 mmHg to obtain 10 g of a colorless liquid. This product is IR, ¹ H-NMR, ²⁹ Si-NMR, GC-
From each spectrum of MS, it was found to be cyclopentasilane.

Synthesis Example 2 Under an argon atmosphere, 10 g of the cyclopentasilane obtained in Synthesis Example 1 was added to a 150 mL flask and irradiated with a 500 W high pressure mercury lamp for 30 minutes while stirring. The obtained white solid was insoluble in organic solvents such as toluene and cyclohexane. When 100 g of the cyclopentasilane obtained in Synthesis Example 1 was added to this, a colorless transparent solution was obtained.

Synthesis Example 3 Under an argon atmosphere, 2 g of cyclopentasilane (Si ₅ H ₁₀ ) obtained in Synthesis Example 1 was dissolved in 18 g of propylene glycol monoisopropyl ether to prepare a composition solution.

Example 1 The solution obtained in Synthesis Example 2 was applied onto an 8-inch silicon wafer under a nitrogen gas atmosphere by using a spin coater under the conditions of a rotation speed of 1000 rpm and 15 seconds. Then, after heating for 5 minutes using a hot plate kept at a temperature of 150 ° C. to evaporate the solvent and the like, it is heated for 5 minutes using a hot plate kept at 400 ° C. to form an interlayer insulating film on the silicon wafer. Was formed. The film thickness of the obtained interlayer insulating film is measured by an optical film thickness meter (Rudolph Techn).
Spectra Laser20 manufactured by the logistics company
0) was used to measure 50 points on the coating film surface. The average value of the film thickness was 0.4506 μm, and 3σ was as good as 0.0067 μm. Further, aluminum was vapor-deposited on the substrate on which the interlayer insulating film was obtained in the same manner as described above to prepare a dielectric constant evaluation substrate. HP16415B electrode and H
10k using P4284A Precision LCR meter (both manufactured by Yokogawa Hewlett-Packard Co.)
When the relative dielectric constant of the interlayer insulating film was calculated from the capacitance value at Hz, it was 2.25, which was a very low value. further,
Regarding the substrate on which an interlayer insulating film was obtained in the same manner as described above, 1 mm x 1 mm according to the cross-cut tape method of 8.5. 2 in the adhesion test of JIS K-5400 (1900) 8.5. A cut was made with a cutter knife so that 10 × 10 cross-cuts were formed, and an adhesion test was conducted. As a result, there was no peeled portion, and the adhesion was good.

Example 2 An interlayer insulating film was formed and evaluated according to the method of Example 1 except that the solution obtained in Synthesis Example 3 was used. The average film thickness of the obtained interlayer insulating film was 0.5051 μm, and 3σ was as good as 0.0075 μm. Moreover, when the relative permittivity of the coating film was evaluated, it showed a very low permittivity of 2.10. Furthermore, as a result of the adhesion evaluation, no peeled part was found,
It was found that the adhesion was good.

[0039]

As described above, according to the present invention, there is provided a method for forming an interlayer insulating film having excellent dielectric properties and excellent adhesion balance to the underlying layer.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) H01L 21/768 H01L 21/90 QF Term (Reference) 4J038 DL011 JA17 JA35 KA02 NA21 PA17 PA19 5F033 RR09 RR21 RR25 SS22 XX14 XX24 5F058 AA03 AA08 AG01 AG09 AH02

Claims (4)

[Claims] 1. A substrate of the formula (A) Si _n R _m (where n represents an integer of 3 or more, m represents an integer of n to (2n + 2), and m Rs are independent of each other. Is a hydrogen atom, an alkyl group, a phenyl group, or a halogen, provided that when all of m Rs are hydrogen atoms and m = 2n, n is an integer of 7 or more. And a (B) at least one silicon compound selected from the group consisting of cyclopentasilane, cyclohexasilane, and silylcyclopentasilane.
Alternatively, a method for forming an interlayer insulating film, which is characterized by performing light treatment. 2. A (A ′) formula Si _i H _{2i + 2 is formed} on a substrate.
(Here, i is an integer of 2 to 8.) A hydrogenated chain silane compound represented by the formula Si _j H _2j (where j is 3).
It is an integer of -10. ) And a hydrogenated cyclic silane compound represented by Si) and a hydrogenated cage silane compound represented by Si _k H _k (where k is an integer of 6 to 10). A coating film containing a product formed by the silane compound of (1) being exposed to light, and (B) at least one silicon compound selected from the group consisting of cyclopentasilane, cyclohexasilane, and silylcyclopentasilane. A method of forming an interlayer insulating film, which comprises forming and then heat and / or light treating. To 3. A substrate, in (A ") formula _Si n _{R m} (wherein, n represents an integer of 3 or more, m is and a plurality of R represents an integer of n~ (2n + 2) are each Independently represents a hydrogen atom, an alkyl group, a phenyl group or a halogen), and (C) a reaction product with a compound selected from the group consisting of an organic hydroxy compound and an organic carboxylic acid. A method for forming an interlayer insulating film, which comprises forming a film and then performing heat and / or light treatment. 4. A (A ″) formula Si _n R _m (where n represents an integer of 3 or more, m represents an integer of n to (2n + 2), and a plurality of Rs are mutually present on the substrate. A compound represented by a hydrogen atom, an alkyl group, a phenyl group or a halogen) and a mixture of the compound (C) with a compound selected from the group consisting of an organic hydroxy compound and an organic carboxylic acid. A method of forming an interlayer insulating film, which comprises forming and then heat and / or light treating.