JP2009188046A - Laminated body and method for producing the same - Google Patents

Abstract

A laminated body with reduced leakage current and a method for manufacturing the same are provided.
A laminate includes a base material, a silica-based insulating portion provided above the base material, a conductive portion provided in the silica-based insulating portion, and the silica-based insulating portion and the conductive portion. A barrier layer provided on the barrier layer, the barrier layer including polycarbosilane.
[Selection] Figure 1

Description

  The present invention relates to a laminate and a method for producing the same.

  In recent years, with the miniaturization of semiconductor devices, a multilayer wiring technique is used to connect wirings formed in layers having different levels. As such multilayer wiring technology, for example, a first wiring layer provided on an insulating layer, an interlayer insulating layer covering the first wiring layer and having a contact hole on the first wiring layer, and a contact A multilayer wiring structure having a second wiring layer provided on the hole is exemplified. In this case, the contact hole is provided with a contact layer that is a conductive portion that electrically connects the first wiring layer and the second wiring layer. Copper may be used as a material constituting the conductive portion such as the contact layer and the wiring layer.

  Copper is a useful material because it can reduce wiring delay and improve high-speed operability. However, while having such advantages, it is known that copper has a material that easily diffuses into various insulating layers such as an interlayer insulating layer. Copper diffusion contributes to lowering the insulating properties of the insulating layer. For this reason, when forming an electroconductive part using copper, the barrier layer for suppressing the spreading | diffusion of copper may be formed on an electroconductive part (Unexamined-Japanese-Patent No. 2005-311069).

Further, miniaturized semiconductor devices are required to reduce leakage current and reduce power consumption. Accordingly, the barrier layer is required to reduce leakage current by suppressing copper diffusion.
JP 2005-311069 A

  The present invention provides a laminate with reduced leakage current and a method for manufacturing the same.

The laminate according to one embodiment of the present invention is
A substrate;
A silica-based insulating portion provided above the substrate;
A conductive portion provided in the silica-based insulating portion;
A barrier layer provided on the silica-based insulating portion and the conductive portion;
Including
The barrier layer includes polycarbosilane.

  In the laminate, the polycarbosilane is a polymer having a repeating structural unit represented by the following general formula (1) or a polymer having a repeating structural unit represented by the following general formula (2). Can do.

・・・・・（１）
（式中、Ｒ^１，Ｒ^２は独立して、水素原子、炭素数１〜３０の置換基を有してもよいアルキル基、炭素数１〜３０の置換基を有してもよいアルケニル基、炭素数１〜３０の置換基を有してもよいアルキニル基、または、置換基を有してもよい芳香族基を表し、Ｒ^３は、−Ｃ≡Ｃ−、少なくとも１つの−Ｃ≡Ｃ−と連結した置換基を有してもよい−ＣＨ_２−、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよいアルキレン基、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよいアルケニレン基、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよいアルキニレン基、または、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよい２価の芳香族基を表す。）

(1)
(In the formula, R ¹ and R ² are independently a hydrogen atom, an alkyl group which may have a substituent having 1 to 30 carbon atoms, or an alkenyl group which may have a substituent having 1 to 30 carbon atoms. Represents an alkynyl group which may have a substituent having 1 to 30 carbon atoms, or an aromatic group which may have a substituent, and R ³ represents —C≡C—, at least one —C≡. —CH ₂ — which may have a substituent linked to C—, an alkylene group which may have a substituent of 2 to 30 carbon atoms linked to at least one —C≡C—, at least one — Alkenylene group optionally having 2 to 30 carbon atoms linked to C≡C—, Alkynylene optionally having 2 to 30 carbon atoms linked to at least one —C≡C— Or a substituent having 2 to 30 carbon atoms linked to at least one —C≡C—. It represents the valence of the aromatic group.)

・・・・・（２）
（式中、Ｒ^４およびＲ^５は独立して、水素原子、１〜４個の炭素原子を有しているアルキル基またはアリール基を表し、Ｒ^６はメチレン基またはメチン基を表し、ｍおよびｎは、それぞれ、１０＜ｍ＋ｎ＜１０００およびｎ／ｍ＜０．３の条件を満たす正の整数を表す。）

(2)
Wherein R ⁴ and R ⁵ independently represent a hydrogen atom, an alkyl group or an aryl group having 1 to 4 carbon atoms, R ⁶ represents a methylene group or a methine group, m and n represents a positive integer that satisfies the conditions of 10 <m + n <1000 and n / m <0.3, respectively.

  In the stacked body, the conductive part may include copper.

  In the laminate, the base material may include at least one layer selected from Si, SiGe, GaAs, InP, GaP, and GaN.

A method for manufacturing a laminate according to one embodiment of the present invention includes:
Forming a silica-based insulating portion above the substrate;
Forming a conductive portion in the silica-based insulating portion;
Forming a coating film on the silica-based insulating part and the conductive part using a film-forming composition containing polycarbosilane; and curing the coating film to form a barrier layer;
including.

  In this case, the coating film can be cured by at least one selected from heating, electron beam irradiation, and ultraviolet irradiation.

  In this case, the coating film can be cured by a combination of heating and electron beam irradiation or ultraviolet irradiation.

  According to the above laminate, since the barrier layer is made of polycarbosilane, the diffusion of the metal (for example, copper) constituting the conductive portion can be suppressed, so that the leakage current can be greatly reduced.

1. Hereinafter, the present invention will be described in more detail with reference to FIG. FIG. 1 is a cross-sectional view schematically showing a laminate according to an embodiment of the present invention.

1.1. Structure of Laminate As shown in FIG. 1, the laminate according to the present embodiment has a silica-based insulating part 10 provided above the base material 8 and a predetermined pattern provided in the silica-based insulating part 10. It has a conductive part (wiring layer) 20 and a barrier layer 30 provided so as to cover the upper surface of the conductive part 20.

  The base material 8 is, for example, at least one of Si, SiGe, GaAs, InP, GaP, and GaN.

  The conductive part 20 has a predetermined pattern, and examples of the material thereof include known insulating materials. The conductive portion 20 does not need to be formed of a single metal layer, and may have a laminated structure with a metal nitride layer or oxide layer, for example, a titanium nitride layer, a tantalum nitride layer, aluminum An aluminum alloy layer, copper, a copper alloy layer, and the like are exemplified. Among these, it is preferable that the electroconductive part 20 contains copper, for example, consists of copper.

1.2. Barrier layer 1.2.1. Configuration of Barrier Layer The barrier layer 30 is made of polycarbosilane. The barrier layer 30 should just be provided so that the upper surface of the electroconductive part 20 may be covered at least. In the laminate shown in FIG. 1, the barrier layer 30 is provided on the conductive portion 20 and the silica-based insulating portion 10.

  By providing the barrier layer 30 made of polycarbosilane on a conductive portion containing, for example, a metal (for example, copper), diffusion of the metal (copper) to the silica-based insulating portion 10 can be suppressed. Thereby, since a leak current can be reduced, the insulation of the silica type insulating part 10 can be ensured, and the low power consumption of a semiconductor device can be achieved. A silica-based insulating portion (not shown) is provided on the barrier layer 30, and a wiring layer (not shown) is provided on the conductive portion 20. The wiring layer and the conductive portion 20 are electrically connected to each other. A contact layer (not shown) for connection may be further provided.

  The barrier layer 30 can be formed, for example, by curing a coating film formed using a film-forming composition containing polycarbosilane.

1.2.2. Configuration of Polycarbosilane The polycarbosilane contained in the barrier layer 30 is, for example, a polymer having a repeating structural unit represented by the following general formula (1) (hereinafter referred to as “polymer (1)”), and A polymer having a repeating structural unit represented by the following general formula (2) (hereinafter referred to as “polymer (2)”) is preferred.

・・・・・（１）
（式中、Ｒ^１，Ｒ^２は独立して、水素原子、炭素数１〜３０の置換基を有してもよいアルキル基、炭素数１〜３０の置換基を有してもよいアルケニル基、炭素数１〜３０の置換基を有してもよいアルキニル基、または、置換基を有してもよい芳香族基を表し、Ｒ^３は、−Ｃ≡Ｃ−、少なくとも１つの−Ｃ≡Ｃ−と連結した置換基を有してもよい−ＣＨ_２−、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよいアルキレン基、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよいアルケニレン基、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよいアルキニレン基、または、少なくとも１つの−Ｃ≡Ｃ−と連結した炭素数２〜３０の置換基を有してもよい２価の芳香族基を表す。）

(1)
(In the formula, R ¹ and R ² are independently a hydrogen atom, an alkyl group which may have a substituent having 1 to 30 carbon atoms, or an alkenyl group which may have a substituent having 1 to 30 carbon atoms. Represents an alkynyl group which may have a substituent having 1 to 30 carbon atoms, or an aromatic group which may have a substituent, and R ³ represents —C≡C—, at least one —C≡. —CH ₂ — which may have a substituent linked to C—, an alkylene group which may have a substituent of 2 to 30 carbon atoms linked to at least one —C≡C—, at least one — Alkenylene group optionally having 2 to 30 carbon atoms linked to C≡C—, Alkynylene optionally having 2 to 30 carbon atoms linked to at least one —C≡C— Or a substituent having 2 to 30 carbon atoms linked to at least one —C≡C—. It represents the valence of the aromatic group.)

Examples of the alkyl group which may have a substituent having 1 to 30 carbon atoms represented by R ¹ and R ² include a methyl group, an ethyl group, a propyl group, a hexyl group, a cyclohexyl group, an octyl group, and a dodecanyl group. , A trifluoromethyl group, a 3,3,3-trifluoropropyl group, a chloromethyl group, an aminomethyl group, a hydroxymethyl group, a silylmethyl group, a 2-methoxyethyl group, and a substituent having 1 to 30 carbon atoms. Examples of the alkenyl group that may be present include a vinyl group, 2-propenyl group, isopropenyl group, 3-butenyl group, 5-hexenyl group, 1,3-butadienyl group, 3,3,3-trifluoro- Examples of the alkynyl group that may have a substituent having 1 to 30 carbon atoms include, for example, an ethynyl group, a 1-propynyl group, and 2-propynyl group. Group, butynyl group, trimethylsilylethynyl group, and phenylethynyl group. Examples of the aromatic group that may have a substituent include a phenyl group, a naphthyl group, a pyrazinyl group, a 4-methylphenyl group, and 4-vinyl. Phenyl group, 4-ethynylphenyl group, 4-aminophenyl group, 4-chlorophenyl group, 4-hydroxyphenyl group, 4-carboxyphenyl group, 4-methoxyphenyl group, 4-silylphenyl group, and the like of R ³ Examples of —CH ₂ — which may have a substituent linked to at least one —C≡C— include, for example, a group in which one or two —C≡C— is bonded to a methylene group, a fluoromethylene group or the like. Examples of the alkylene group which may have a substituent having 2 to 30 carbon atoms linked to at least one —C≡C— include, for example, an ethylene group, Examples include a group in which 1 or 2 of —C≡C— is bonded to a propylene group, a tetramethylene group, a tetrafluoroethylene group, etc., and a substituent having 2 to 30 carbon atoms linked to at least one of —C≡C—. Examples of the alkenylene group that may be included include a group in which one or two —C≡C— is bonded to a vinylene group, a propenylene group, a butadienylene group, and the like, and is linked to at least one —C≡C—. Examples of the alkynylene group which may have a substituent having 2 to 30 carbon atoms include a group in which one or two —C≡C— is bonded to an ethynylene group, a propynylene group, a butynylene group, or the like. Examples of the divalent aromatic group which may have a substituent linked to two —C≡C— include, for example, a phenylene group, a naphthylene group, a biphenylene group, an anthracenedil group, a pyridinedyl group Group, thiophenedylyl group, fluorophenylene group, chlorophenylene group, methylphenylene group, silylphenylene group, hydroxyphenylene group, aminophenylene group, phenylenemethylenephenylene group, phenyleneoxyphenylene group, phenylenepropylidenephenylene group, phenylene ( Hexafluoropropylidene) groups having 1 or 2 -C≡C- bonded to a phenylene group.

  Specific examples of the repeating structural unit of the polymer (1) include silylene ethynylene, methylsilylene ethynylene, phenylsilylene ethynylene, silylene ethynylene-1,3-phenylene ethynylene, and silylene ethynylene-1,4. -Phenyleneethynylene, silyleneethynylene-1,2-phenyleneethynylene, methylsilyleneethynylene-1,3-phenyleneethynylene, methylsilyleneethynylene-1,4-phenyleneethynylene, methylsilyleneethynylene-1, 2-phenyleneethynylene, dimethylsilyleneethynylene-1,3-phenyleneethynylene, dimethylsilyleneethynylene-1,4-phenyleneethynylene, dimethylsilyleneethynylene-1,2-phenyleneethynylene, diethylsilyleneethynylene- 1,3-phenylene ether Nylene, phenylsilyleneethynylene-1,3-phenyleneethynylene, phenylsilyleneethynylene-1,4-phenyleneethynylene, phenylsilyleneethynylene-1,2-phenyleneethynylene, diphenylsilyleneethynylene-1,3- Phenyleneethynylene, hexylsilyleneethynylene-1,3-phenyleneethynylene, vinylsilyleneethynylene-1,3-phenyleneethynylene, ethynylsilyleneethynylene-1,3-phenyleneethynylene, 2-propenylsilyleneethynylene- 1,3-phenyleneethynylene, 2-propynylsilyleneethynylene-1,3-phenyleneethynylene, trifluoromethylrosilyleneethynylene-1,3-phenyleneethynylene, 3,3,3-trifluoropropylsilyleneethynylene -1 3-phenyleneethynylene, 4-methylphenylsilyleneethynylene-1,3-phenyleneethynylene, 4-vinylphenylsilyleneethynylene-1,3-phenyleneethynylene, 4-ethynylphenylsilyleneethynylene-1,3- Phenyleneethynylene, phenylethynylsilyleneethynylene-1,3-phenyleneethynylene, silyleneethynylene (5-methyl-1,3-phenylene) ethynylene, phenylsilyleneethynylene (5-methyl-1,3-phenylene) ethynylene Phenylsilylene ethynylene (5-silyl-1,3-phenylene) ethynylene, phenylsilylene ethynylene (5-hydroxy-1,3-phenylene) ethynylene, phenylsilylene ethynylene-2,7-naphthylene ethynylene, silylene Ethynylene-5,1 0-anthracenedylethynylene, phenylsilyleneethynylene-4,4′-biphenyleneethynylene, phenylsilyleneethynylene-1,4-phenylenemethylene-1 ′, 4′-phenyleneethynylene, phenylsilyleneethynylene-1 , 4-phenylene-2,2-propylidene-1 ′, 4′-phenyleneethynylene, phenylsilyleneethynylene-1,4-phenylene-2,2- (1,1,1,3,3,3-hexa Fluoropropylidene) -1 ′, 4′-phenyleneethynylene, phenylsilyleneethynylene-1,4-phenyleneoxy-1 ′, 4′-phenyleneethynylene phenylsilyleneethynylene-2,5-pyridinediethylethynylene , Phenylsilyleneethynylene-2,5-thiophenedyrylethynylene, methylsilylenee Tinylenemethyleneethynylene, phenylsilylene-1,4-phenylene (phenylsilylene) ethynylene-1 ′, 3-phenyleneethylinylene, phenylsilyleneoxy (phenylsilylene) ethynylene, phenylsilyleneoxy (phenylsilylene) ethynylene-1 ′ , 4′-phenyleneethynylene, phenylsilyleneimino (phenylsilylene) ethynylene-1 ′, 3′-phenyleneethynylene, phenylsilyleneimino (phenylsilylene) ethynylene-1 ′, 4′-phenyleneethynylene, silylene-1, 3-phenyleneethynylene, silylene-1,4-phenyleneethynylene, silylene-1,2-phenyleneethynylene, phenylsilylene-1,3-phenyleneethynylene, phenylsilylene-1,4-phenyleneethynylene, fluoro Nylsilylene-1,2-phenyleneethynylene, diphenylsilylene-1,3-phenyleneethynylene, methylsilylene-1,3-phenyleneethynylene, methylsilylene-1,4-phenyleneethynylene, methylsilylene-1,2- Phenyleneethynylene, dimethylsilylene-1,3-phenyleneethynylene, diethylsilylene-1,3-phenyleneethynylene, phenylsilylene-1,3-butadienylene, diphenylsilylene-1,3-butadienylene, phenylsilylenemethyleneethynylene, Diphenylsilylenemethyleneethynylenemethylene, phenylsilylenemethyleneethynylenemethylene, silylene-1,4-phenyleneethynylene-1 ′, 4′-phenylene, methylsilylene-1,4-phenyleneethynylene-1 ′, 4′-fu Ylene, dimethylsilylene-1,4-phenylene ethynylene-1 ', 4'-phenylene, silylene-1,4-phenylene ethynylene-1', 4'-phenylene, and the like.

・・・・・（２）
（式中、Ｒ^４およびＲ^５は独立して、水素原子、１〜４個の炭素原子を有しているアルキル基またはアリール基を表し、Ｒ^６はメチレン基またはメチン基を表し、ｍおよびｎは、それぞれ、１０＜ｍ＋ｎ＜１０００およびｎ／ｍ＜０．３の条件を満たす正の整数を表す。）

(2)
Wherein R ⁴ and R ⁵ independently represent a hydrogen atom, an alkyl group or an aryl group having 1 to 4 carbon atoms, R ⁶ represents a methylene group or a methine group, m and n represents a positive integer that satisfies the conditions of 10 <m + n <1000 and n / m <0.3, respectively.

In the polymer (2), examples of the alkyl group represented by R ⁴ and R ⁵ include a methyl group, an ethyl group, a propyl group, a hexyl group, a cyclohexyl group, an octyl group, a dodecanyl group, a trifluoromethyl group, 3, 3, Examples include 3-trifluoropropyl group, chloromethyl group, aminomethyl group, hydroxymethyl group, silylmethyl group, 2-methoxyethyl group, etc. Examples of the aryl group of R ⁴ and R ⁵ include, for example, phenyl group, naphthyl Group, pyrazinyl group, 4-methylphenyl group, 4-vinylphenyl group, 4-ethynylphenyl group, 4-aminophenyl group, 4-chlorophenyl group, 4-hydroxyphenyl group, 4-carboxyphenyl group, 4-methoxyphenyl Group, 4-silylphenyl group.

In the polymer (2), the alkyl group represented by R ⁶ includes methyl group, ethyl group, propyl group, hexyl group, cyclohexyl group, octyl group, dodecanyl group, trifluoromethyl group, 3,3,3-trimethyl. Examples thereof include a fluoropropyl group, a chloromethyl group, an aminomethyl group, a hydroxymethyl group, a silylmethyl group, and a 2-methoxyethyl group. Examples of the aryl group for R ⁶ include a phenyl group, a naphthyl group, a pyrazinyl group, 4 -Methylphenyl group, 4-vinylphenyl group, 4-ethynylphenyl group, 4-aminophenyl group, 4-chlorophenyl group, 4-hydroxyphenyl group, 4-carboxyphenyl group, 4-methoxyphenyl group, 4-silylphenyl Groups and the like.

  Although there is no restriction | limiting in particular in the weight average molecular weight of polycarbosilane, Preferably it is 500-500,000. These polycarbosilanes are usually solid or liquid at room temperature.

  As a method for producing polycarbosilane, for example, a method of dehydrogenating copolymerization of a diethynyl compound and a silane compound using a basic oxide, a metal hydride, or a metal compound as a catalyst (JP-A-7-90085, JP (Kaihei 10-120687, JP-A-11-158187), a method for dehydrogenative polymerization of an ethynylsilane compound using a basic oxide as a catalyst (JP-A-9-143271), an organomagnesium reagent and dichlorosilanes And a method of dehydrogenating copolymerization of a diethynyl compound and a silane compound using cuprous chloride and a tertiary amine as a catalyst (Hua Qin, JP-A-7-102069, JP-A-11-029579) Liu and John F. Harrod, The Canadian Journal of Che istry, Vol. 68, 1100-1105 (1990)), and a method of dehydrogenating copolymerization of a diethynyl compound and a silane compound using magnesium oxide as a catalyst (Japanese Patent Laid-Open Nos. 7-90085 and 10-204181). However, it is not particularly limited to these methods.

1.2.3. Film Forming Composition In forming the barrier layer, it is preferable to form a coating film using a film forming composition in which polycarbosilane is dissolved or dispersed in an organic solvent.

1.2.3-1. Organic solvent Examples of the organic solvent used in the film-forming composition include ketone solvents, amide solvents, ether solvents, ester solvents, aliphatic hydrocarbon solvents, aromatic solvents, and halogen-containing solvents. And at least one selected from.

  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, methyl-n. -Hexyl ketone, di-i-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonyl acetone, diacetone alcohol, Examples include acetophenone and fenchon. These ketone solvents may be used alone or in combination of two or more.

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

  Examples of the ether solvent include 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- Ethyl butyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethyl 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, mention may be made of the anisole. These ether solvents may be used alone or in combination of two or more.

  Examples of the ester solvent 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, acetic acid. sec-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, aceto Methyl acetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol acetate Mono-n-butyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, glycol diacetate Methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, Mention may be made of diethyl malonate, dimethyl phthalate, diethyl phthalate and the like. 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- Examples include octane, cyclohexane, and methylcyclohexane. These aliphatic hydrocarbon solvents may be used alone or in combination of two or more.

  Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propyl benzene, i-propyl benzene, diethyl benzene, i-butyl benzene, triethyl benzene, di-i-propyl. Examples include benzene, n-amylnaphthalene, trimethylbenzene, and the like. These aromatic hydrocarbon solvents may be used alone or in combination of two or more.

  Examples of the halogen-containing solvent include dichloromethane, chloroform, chlorofluorocarbon, chlorobenzene, dichlorobenzene, and the like.

  In the film-forming composition, it is preferable to use an organic solvent having a boiling point of less than 250 ° C., and the organic solvent species are more preferably a ketone solvent, an ester solvent, or an aromatic hydrocarbon solvent, and these solvents More preferably, one or more of them are used simultaneously.

1.3.3-2. Other Additives The film-forming composition may further contain components such as a curing accelerator, colloidal silica, colloidal alumina, an organic polymer, a surfactant, a silane coupling agent, and a triazene compound.

  Examples of the curing accelerator include organic peroxides and organic azo compounds. As the organic peroxide, for example, BPO (benzoyl peroxide), pertetra A, parkmill D (dicumyl peroxide), BTTB (3,3 ′, 4,4′-tetrabutylperoxycarbonylbenzophenone) (all Nippon Oil & Fats Co., Ltd.). Examples of the organic azo compound include 2,2′-azobisisobutyronitrile (AIBN), dimethyl-2,2′-azobis (2-methylpropionate) (V-601, Wako Pure Chemical Industries, Ltd.) Product), 1,1′-azobis (1-acetoxy-1-phenylethane) (OT (azo) -15, manufactured by Otsuka Chemical Co., Ltd.), and the like.

  The blending amount of the curing accelerator is preferably 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass with respect to 100 parts by mass of the film-forming composition.

  Colloidal silica is, for example, a dispersion in which high-purity silicic acid is dispersed in a hydrophilic organic solvent, and usually has an average particle size of 5 to 30 μm, preferably 10 to 20 μm, and has a solid content. The concentration is usually 10 to 40% by mass. Examples of such colloidal silica include Nissan Chemical Industries, Ltd., methanol silica sol and isopropanol silica sol (Catalyst Chemical Industries, Ltd., trade name “Oscar”).

  Examples of the colloidal alumina include trade names “Alumina Sol 520”, “Alumina Sol 100”, “Alumina Sol 200” manufactured by Nissan Chemical Industries, Ltd., and “Alumina Clear Sol” manufactured by Kawaken Fine Chemical Co., Ltd. “Alumina sol 10” and “Alumina sol 132” can be mentioned.

  Examples of the organic polymer include a polymer having a sugar chain structure, a vinylamide polymer, a (meth) acrylic polymer, an aromatic vinyl compound polymer, a dendrimer, a polyimide, a polyamic acid, a polyarylene, a polyamide, and a polyquinoxaline. , Polyoxadiazole, a fluorine-based polymer, a polymer having a polyalkylene oxide structure, and the like.

  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 alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, ethylene oxide derivative of alkylphenol formalin condensate, polyoxyethylene poly Ether type compounds such as oxypropylene 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 sulfate, etc. Ether 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—, and l represents 1 to 90] , M represents 10 to 99, and n represents a number of 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, More preferred examples include ether type compounds. These may be used alone or in combination of two or more.

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

  Examples of the fluorosurfactant include 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctyl hexyl ether, Octaethylene glycol di (1,1,2,2-tetrafluorobutyl) ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl) ether, octapropylene glycol di (1,1,1, 2,2-tetrafluorobutyl) ether, hexapropylene glycol di (1,1,2,2,3,3-hexafluoropentyl) ether, sodium perfluorododecylsulfonate, 1,1,2,2,8, 8,9,9,10,10-Decafluorododecane, 1,1,2,2,3,3-hexafluorodecane, N- [3- (perfluoro Kutansulfonamido) propyl] -N, N′-dimethyl-N-carboxymethyleneammonium betaine, perfluoroalkylsulfonamidopropyltrimethylammonium salt, perfluoroalkyl-N-ethylsulfonylglycine salt, bis (N-perfluorophosphate) Octylsulfonyl-N-ethylaminoethyl), monoperfluoroalkylethyl phosphate ester and the like, a fluorosurfactant comprising a compound having a fluoroalkyl or fluoroalkylene group at at least one of its terminal, main chain and side chain Can be mentioned.

  Commercially available fluorosurfactants include Megafac F142D, F172, F173, and F183 (above, manufactured by Dainippon Ink & Chemicals, Inc.), Ftop EF301, 303, and 352 (new) Akita Kasei Co., Ltd.], Florard FC-430, FC-431 (Sumitomo 3M Co., Ltd.), Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 [Asahi Glass Co., Ltd.], BM-1000, BM-1100 (Yusho Co., Ltd.), NBX-15 [Neos Co., Ltd.] And fluorine-based surfactants that are commercially available. Among these, Megafac F172, BM-1000, BM-1100, and NBX-15 are particularly preferable.

  As the silicone surfactant, for example, SH7PA, SH21PA, SH30PA, ST94PA [all manufactured by Toray Dow Corning Silicone Co., Ltd.] can be used. Among these, SH28PA and SH30PA are particularly preferable.

  The usage-amount of surfactant is 0.00001-1 mass part normally with respect to 100 mass parts of polymers (1) and (2). These surfactants may be used alone or in combination of two or more.

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

  Examples of the triazene compound include 1,2-bis (3,3-dimethyltriazenyl) benzene, 1,3-bis (3,3-dimethyltriazenyl) benzene, and 1,4-bis (3,3 -Dimethyltriazenyl) benzene, bis (3,3-dimethyltriazenylphenyl) ether, bis (3,3-dimethyltriazenylphenyl) methane, bis (3,3-dimethyltriazenylphenyl) sulfone, Bis (3,3-dimethyltriazenylphenyl) sulfide, 2,2-bis [4- (3,3-dimethyltriazenylphenoxy) phenyl] -1,1,1,3,3,3-hexafluoro Propane, 2,2-bis [4- (3,3-dimethyltriazenylphenoxy) phenyl] propane, 1,3,5-tris (3,3-dimethyltriazenyl) ben 2,7-bis (3,3-dimethyltriazenyl) -9,9-bis [4- (3,3-dimethyltriazenyl) phenyl] fluorene, 2,7-bis (3,3- Dimethyltriazenyl) -9,9-bis [3-methyl-4- (3,3-dimethyltriazenyl) phenyl] fluorene, 2,7-bis (3,3-dimethyltriazenyl) -9, 9-bis [3-phenyl-4- (3,3-dimethyltriazenyl) phenyl] fluorene, 2,7-bis (3,3-dimethyltriazenyl) -9,9-bis [3-propenyl- 4- (3,3-dimethyltriazenyl) phenyl] fluorene, 2,7-bis (3,3-dimethyltriazenyl) -9,9-bis [3-fluoro-4- (3,3-dimethyl) Triazenyl) phenyl] fluorene, 2,7-bis ( , 3-Dimethyltriazenyl) -9,9-bis [3,5-difluoro-4- (3,3-dimethyltriazenyl) phenyl] fluorene, 2,7-bis (3,3-dimethyltriazeni) ) -9,9-bis [3-trifluoromethyl-4- (3,3-dimethyltriazenyl) phenyl] fluorene and the like. These triazene compounds may be used alone or in combination of two or more.

  The total solid concentration of the film-forming composition is preferably 1 to 30% 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 this embodiment is 1 to 30% by mass, the film thickness of the coating film is in an appropriate range, and the storage stability is more excellent.

  In the case where a film-forming composition is applied to a substrate to form a coating film, examples of the coating means include spin coating, dipping method, roll coating method, spray method, and scan coating method.

2. Next, an example of the manufacturing method of the laminated body shown in FIG. 1 is demonstrated.

  First, the silica-based insulating part 10 and the conductive part 20 having a predetermined pattern are formed. The conductive portion 20 can be performed by a known technique, and can be formed by, for example, a damascene method. As the material of the conductive portion 20, the above-described conductive material can be used.

  Next, a barrier layer 30 is formed thereon so as to cover at least the conductive portion 20. First, a coating film is formed on the silica-based insulating part 10 and the conductive part 20 using the above-described film-forming composition containing polycarbosilane, and then the coating film is cured to form the barrier layer 30.

  The coating film can be formed by, for example, spin coating, dipping method, roll coating method, spraying method or the like. The coating film is preferably dried at room temperature as required.

  Moreover, it is preferable that hardening of a coating film is performed by at least 1 sort (s) chosen from a heating, electron beam irradiation, and ultraviolet irradiation.

  When the coating is cured by heating, it is preferably performed at 300 to 450 ° C, more preferably 350 to 400 ° C. In this case, the heating time is usually preferably less than 60 minutes, and more preferably less than 30 minutes. Moreover, when hardening a coating film by ultraviolet irradiation, it is preferable that the wavelength of the ultraviolet-ray used for ultraviolet irradiation is 300 nm or less, and it is more preferable that it is 220-270 nm.

  As the heating means, for example, a hot plate, an oven, a furnace, or the like can be used.

  In order to obtain a homogeneous film with a small leakage current in a short time, the coating film is more preferably cured by a combination of heating and electron beam irradiation or ultraviolet irradiation. In this case, the film can be cured with a curing time of 10 minutes or less (for example, 1 to 5 minutes).

  Next, a silica-based insulating portion (not shown) is formed on the barrier layer 30, and a wiring layer (not shown) can be formed by a single damascene method or a dual damascene method. The semiconductor device including the stacked body according to this embodiment can be obtained through the above steps.

3. EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the following description shows the example of an aspect of this invention generally, and this invention is not limited by this description without a particular reason. In addition, unless otherwise indicated, the part and% in an Example and a comparative example have shown that they are a weight part and weight%, respectively.

3.1. Evaluation Method The film-forming composition and the film were evaluated as follows.

3.1.1. Weight average molecular weight (Mw)
The weight average molecular weight (Mw) of polycarbosilane was measured by a gel permeation chromatography (GPC) method under the following conditions.
Sample: Tetrahydrofuran was used as a solvent, and 1 g of a sample was prepared by dissolving in 100 cc of tetrahydrofuran.

Standard polystyrene: Standard polystyrene manufactured by US Pressure Chemical Company was used.
Apparatus: High-temperature, high-speed gel permeation chromatogram (trade name “Model 150-C ALC / GPC”) manufactured by Waters, USA
Column: Showa Denko Co., Ltd., trade name “SHODEX A-80M (length 50 cm)”
Measurement temperature: 40 ° C
Flow rate: 1cc / min

3.1.2. Vbd and Leakage Current A sample for measurement was prepared by forming an aluminum electrode pattern by vapor deposition on the films obtained in Examples and Comparative Examples, respectively. The sample was stepped by 0.1 MV / cm on the membrane with a Keithley 6517A electrometer, and the applied voltage (MV / V) when the current density exceeded 1.0 × 10 ⁻² A / cm ² or more. cm) was Vbd, and the current density when the applied voltage was 2 MV / cm was the leakage current (A / cm ² ).

3.1.3. Mean time to failure (MTF)
A copper electrode pattern was formed on each of the films obtained in Examples and Comparative Examples by a vapor deposition method to prepare a sample for MTF measurement. A 3MV / cm electric field strength is applied to the sample using a Keithley 6517A electrometer, and the time when the current density of the film becomes 1.0 × 10 ⁻² A / cm ² is set to a cumulative frequency distribution. The time point at which 50% was reached was defined as MTF.

3.2. Synthesis example 3.2.1. Synthesis Example 1 (Preparation of film-forming composition A for the barrier layer)
A commercially available polycarbosilane (trade name “NIPUSI Type-S”, a carbosilanized polymer of polydimethylsilane available from Nippon Carbon Co., Ltd., hereinafter referred to as “polycarbosilane 1”) is used as n-butyl acetate. In a mixed solvent of cyclohexanone (n-butyl acetate: cyclohexanone = 80: 20 (weight ratio)), and the weight ratio of polycarbosilane 1 to the mixed solvent is polycarbosilane 1: mixed solvent = 10: 90. A solution (Film-forming composition 1) was prepared.

  The weight average molecular weight of this polycarbosilane 1 was 4,700.

3.2.2. Synthesis Example 2 (Preparation of film-forming composition B for the barrier layer)
A solution obtained by dissolving 30 g of chloromethyltrichlorosilane in 300 ml of THF was dropped into 100 ml of THF containing 10 g of magnesium at room temperature over 2 hours. Next, after the obtained reaction solution was reacted at 60 ° C. for 10 hours, 10 ml of a THF solution of vinylmagnesium bromide having a concentration of 1.0 M was added dropwise at room temperature. Subsequently, after removing the produced magnesium salt, 50 g of lithium aluminum hydride was added to this solution in an ice bath, and the mixture was reacted at room temperature for 10 hours. Subsequently, 100 ml of 3M hydrochloric acid aqueous solution was added in an ice bath to deactivate the reaction solution, and then the organic phase and the aqueous phase were separated. By concentrating the obtained organic phase, 9.5 g of polycarbosilane 2 having a weight average molecular weight of 2,200 was obtained.

  The polycarbosilane 2 was dissolved in a mixed solvent of n-butyl acetate and cyclohexanone (n-butyl acetate: cyclohexanone = 80: 20 (weight ratio)), and the weight ratio of the polycarbosilane 2 to the mixed solvent was A solution (film-forming composition B) in which polycarbosilane 2: mixed solvent = 10: 90 was prepared.

3.2.3. Reference Example (Preparation of film-forming composition C for the barrier layer)
In a 1000 ml three-necked flask equipped with a thermometer, an argon gas inlet tube, and a stirrer, 120 ml of tetrahydrofuran, 3.46 g of dichlorobistriphenylphosphine palladium, 1.44 g of copper iodide, 20 ml of piperidine, 4,4′-bis (2-iodo) 185.72 g of phenoxy) benzophenone was added. Next, 65.48 g of 4,4′-diethynyl diphenyl ether was added and reacted at 25 ° C. for 20 hours. This reaction solution was reprecipitated twice with 5 liters of methanol, then dissolved in cyclohexanone, washed twice with ultrapure water, further reprecipitated with 5 liters of methanol, the precipitate was filtered and dried, and the weight average molecular weight was 35 1,000 polymers A were obtained. 2 g of this polymer A and 0.05 g of polyvinyl methoxysiloxane having a weight average molecular weight of 500 are dissolved in 18 g of cyclohexanone and filtered through a 0.2 μm pore size polytetrafluoroethylene (manufactured by DuPont, Teflon (registered trademark)) filter. A forming composition C was obtained.

3.3. Examples and Comparative Examples Film forming compositions A to C were respectively applied to an 8-inch silicon wafer by using a spin coating method to form a coating film, and a nitrogen atmosphere at 90 ° C. for 3 minutes on a hot plate After drying the substrate at 200 ° C. for 3 minutes, the substrate was heated with a hot plate for 60 minutes under the temperature conditions and atmosphere shown in Table 1, respectively, and the films of Examples 1 to 4 and Comparative Examples 1 to 2 were formed. Formed. Nitrogen was used as an atmosphere for heating the coating film, and the film thickness of the finally obtained film was 0.5 μm.

  In Example 1, Example 3, and Comparative Example 5, the coating film was subjected to heat treatment and ultraviolet irradiation at the same time. Here, the wavelength of the irradiated ultraviolet rays was 0.4 μm or less (manufactured by Axcelis Technologies, Rapid Cure 320CE).

  Moreover, in Example 2, the heat processing with respect to the coating film and electron beam irradiation were performed simultaneously. Here, Ectus manufactured by Tokyo Electron was used as the electron beam irradiation device.

  As shown in Table 1, according to Examples 1 to 4, when the barrier layer contains polycarbosilane, the leakage current can be reduced as compared with Comparative Examples 1 and 2 in which the barrier layer is made of an organic polymer. confirmed. Thereby, it can be understood that the diffusion of copper could be suppressed by the barrier layers of Examples 1 to 4.

  Further, according to Examples 1 to 4, since the barrier layer contains polycarbosilane, the average failure time is longer than that of Comparative Examples 1 and 2 in which the barrier layer is made of an organic polymer. It can be understood that the diffusion is suppressed.

It is sectional drawing which shows typically an example of the laminated body of this invention.

Explanation of symbols

8 Base material 10 Silica-based insulating part 20 Conductive part (wiring layer)
30 Barrier layer

Claims (7)

A substrate;
A silica-based insulating portion provided above the substrate;
A conductive portion provided in the silica-based insulating portion;
A barrier layer provided on the silica-based insulating portion and the conductive portion;
Including
The barrier layer is a laminate including polycarbosilane. In claim 1,
The said polycarbosilane is a laminated body which is a polymer which has a repeating structural unit represented by following General formula (1), or a polymer which has a repeating structural unit represented by following General formula (2).

(1)
(In the formula, R ¹ and R ² are independently a hydrogen atom, an alkyl group which may have a substituent having 1 to 30 carbon atoms, or an alkenyl group which may have a substituent having 1 to 30 carbon atoms. Represents an alkynyl group which may have a substituent having 1 to 30 carbon atoms, or an aromatic group which may have a substituent, and R ³ represents —C≡C—, at least one —C≡. —CH ₂ — which may have a substituent linked to C—, an alkylene group which may have a substituent of 2 to 30 carbon atoms linked to at least one —C≡C—, at least one — Alkenylene group optionally having 2 to 30 carbon atoms linked to C≡C—, Alkynylene optionally having 2 to 30 carbon atoms linked to at least one —C≡C— Or a substituent having 2 to 30 carbon atoms linked to at least one —C≡C—. It represents the valence of the aromatic group.)

(2)
Wherein R ⁴ and R ⁵ independently represent a hydrogen atom, an alkyl group or an aryl group having 1 to 4 carbon atoms, R ⁶ represents a methylene group or a methine group, m and n represents a positive integer that satisfies the conditions of 10 <m + n <1000 and n / m <0.3, respectively. In claim 1 or 2,
The conductive part is a laminate including copper. In any of claims 1 to 3,
The base material includes a laminate including at least one layer selected from Si, SiGe, GaAs, InP, GaP, and GaN. Forming a silica-based insulating portion above the substrate;
Forming a conductive portion in the silica-based insulating portion;
Forming a coating film on the silica-based insulating part and the conductive part using a film-forming composition containing polycarbosilane; and curing the coating film to form a barrier layer;
The manufacturing method of a laminated body containing this. In claim 5,
The coating film is cured by at least one selected from heating, electron beam irradiation, and ultraviolet irradiation. In claim 6,
The coating film is cured by a combination of heating and electron beam irradiation or ultraviolet irradiation.

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