JP2006111740A - Composition for surface hydrophobizing, surface hydrophobizing method, semiconductor device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition for surface hydrophobizing intended for repairing damage in a siloxane insulating layer following etching/ashing, which is used for an electronic device such as a semiconductor device, a surface hydrophobizing method, a semiconductor device and its manufacturing method. <P>SOLUTION: The composition comprises a silane compound, e.g. bis(trimethylsilyl)malonate, 1,2-bis(trimetylsiloxy)ethane, tetrakis(trimethylsiloxy)titanium, etc. and an organic solvent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a composition for hydrophobizing a surface of a layer used in an electronic device such as a semiconductor device, a method for hydrophobizing a surface, a semiconductor device, and a method for manufacturing the same.

Currently, a silica (SiO ₂ ) film formed by a vacuum process such as a CVD method is frequently used as an interlayer insulating layer of a semiconductor device in a large scale integrated circuit (LSI) or the like. In recent years, for the purpose of forming an insulating layer having a more uniform film thickness, a coating type insulating layer called an SOG (Spin on Glass) film mainly composed of a hydrolysis product of alkoxysilane has also been used. It has become so.

  In the manufacturing process of a semiconductor device, various processes are generally performed on an insulating layer. For example, the insulating layer is patterned by etching or the resist is removed by ashing. The oxidizing or reducing reactive gas used at that time may cause the carbon atom and the hydrogen atom in the insulating layer to be eliminated and a hydrophilic silanol group (—Si—OH) may be generated. As a result, the hygroscopicity of the film is increased, and various device reliability may be lowered by the adsorbed moisture.

  In particular, when the insulating layer is an insulating film, the generation of silanol groups means an increase in the dielectric constant, and when the damage is significant, the insulating film may lose its low dielectric constant. .

US Pat. No. 6,383,466 US Patent No. US5504042 US Pat. No. 6,548,113 US Pat. No. 6,700,200 specification Philip G. Clerk, 2 others, Cleaning and Restoring k Value of Porous MSQ Films, Semiconductor International, August 2003, 46 -Page 52 Anil Bhanap, 3 others, Repairing Process-Induced Damage to Porous Insulation ILDs by Post-Ash Treatment proceedings Advanced Metalization, Conference XIX, pp519, 2003)

  An object of the present invention is to provide a method for hydrophobizing a surface that has consistency with subsequent processing processes and can repair surface damage more easily and efficiently, and can be used to repair surface damage. The object is to provide a composition for hydrophobizing a surface.

  Another object of the present invention is to provide a semiconductor device including a layer subjected to surface hydrophobization treatment by the surface hydrophobizing method and a method for manufacturing the same.

  1. The composition for surface hydrophobization of the present invention comprises (A) a compound (a-1) represented by the following general formula (1), a compound (a-2) represented by the following general formula (2), and the following general formula It contains at least one silane compound selected from the group of compounds (a-3) represented by formula (3) and (B) an organic solvent.

(1)
^Wherein, R 1, ^{R 2} and ^{R 3} are a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 1 to R ³ is one or zero. ), R ⁴ represents an alkylene group, an alkenylene group, an alkynylene group or a phenylene group. ]

(2)
^Wherein, R 5, ^{R 6} and ^{R 7} are a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 5 to R ⁷ is one or zero. ), R ⁸ represents an alkylene group, an alkenylene group, an alkynylene group or a phenylene group. ]

(3)
^Wherein, R ^{9, R 10,} and ^{R 11} is a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 9 ^{to R 11} is a one or zero. ), M represents Ti or Zr. ]
Here, the composition can be used in contact with the surface of the layer. In this case, the surface can be obtained by etching and / or ashing. In this case, the layer may contain a silicon atom and contain at least one element selected from an oxygen atom, a carbon atom, a hydrogen atom, and a nitrogen atom as a constituent element. Furthermore, in this case, the layer may be an insulating film. Here, the insulating film can be, for example, a film having a relative dielectric constant of 3.0 or less.

  2. The surface hydrophobizing method of the present invention includes a step of heating the layer in the state where the composition for surface hydrophobizing of the present invention is in contact with the surface of the layer.

  In this case, the heating step can include a step of heating the layer at a first temperature and a step of heating the layer at a second temperature higher than the first temperature. Alternatively, in this case, the heating step includes the step of heating the layer at a first temperature, the step of heating the layer at a second temperature higher than the first temperature, and the second temperature. Heating the layer at a higher third temperature.

  Here, in the above-described method, (C) after bringing the acidic catalyst or basic catalyst into contact with the surface, the step of bringing the composition into contact with the surface can be performed.

  3. The semiconductor device of the present invention includes a hydrophobic film obtained by the surface hydrophobization method.

4). The semiconductor device of the present invention is
A semiconductor device including an insulating layer disposed above a substrate,
The insulating layer is provided with a recess,
A hydrophobic film is formed on the inner wall of the recess,
The hydrophobic membrane was obtained by bringing the surface hydrophobizing composition into contact with the inner wall of the recess.

5. The semiconductor device of the present invention is
A semiconductor device including a wiring structure disposed above a substrate,
The wiring structure is
A via layer provided in the first recess;
A wiring layer disposed on the via layer and provided in the second recess,
The first recess is provided in a first insulating layer disposed above the substrate,
The second recess is provided in a second insulating layer disposed above the first insulating layer,
A hydrophobic film is formed on the inner wall of the first recess,
The hydrophobic membrane was obtained by bringing the surface hydrophobizing composition into contact with the inner wall of the first recess.

6). The semiconductor device of the present invention is
A semiconductor device including a wiring structure disposed above a substrate,
The wiring structure is
A via layer provided in the first recess;
A wiring layer disposed on the via layer and provided in the second recess,
The first recess is provided in a first insulating layer disposed above the substrate,
The second recess is provided in a second insulating layer disposed above the first insulating layer,
A first hydrophobic film is formed on the inner wall of the first recess,
A second hydrophobic film is formed on the inner wall of the second recess,
The first hydrophobic film is obtained by bringing the surface hydrophobizing composition into contact with the inner wall of the first recess,
The second hydrophobic film was obtained by bringing the surface hydrophobizing composition into contact with the inner wall of the second recess.

  Here, in the semiconductor device, the via layer and the wiring layer can be integrally formed.

  7. The method for manufacturing a semiconductor device of the present invention includes a step of forming a hydrophobic film by the surface hydrophobization method.

  According to the method for hydrophobizing a surface of the present invention, the composition for hydrophobizing a surface of the present invention diffuses smoothly from the surface into the layer, and the composition reacts quickly with a group near the surface in the layer. Can do. Further, no corrosive by-product is generated. Thereby, damage on the surface can be repaired more easily and efficiently. Further, the surface hydrophobizing method of the present invention has consistency with the subsequent processing process. That is, the surface hydrophobizing composition of the present invention is useful for repairing surface damage by hydrophobizing the surface.

  Since the semiconductor device of the present invention includes a layer having a surface hydrophobized by the surface hydrophobizing method, the semiconductor device is excellent in reliability.

  Since the semiconductor device manufacturing method of the present invention includes a step of forming a surface hydrophobized layer by the surface hydrophobizing method, a semiconductor device having excellent reliability can be manufactured.

  In particular, an insulating film of a semiconductor device, which includes a silicon atom and includes at least one element selected from an oxygen atom, a carbon atom, a hydrogen atom, and a nitrogen atom as a constituent element, The layer may be damaged by a manufacturing process (for example, an etching process or an ashing process performed to remove the photoresist). More specifically, carbon atoms and hydrogen atoms in the layer are desorbed by an oxidizing or reducing reactive gas used in the etching process, ashing process, and other processes, and silanol groups (-SiOH ) Is formed, moisture is easily absorbed in the layer. As a result, moisture in the layer increases, and the absorbed moisture may reduce the reliability of the semiconductor device.

  In the case of an insulating film, when the moisture in the layer increases due to the generation of silanol groups (—SiOH), the dielectric constant may increase and the low dielectric property may be lost. On the other hand, by applying the surface hydrophobizing method of the present invention to the insulating film, the surface hydrophobizing composition of the present invention reacts with silanol groups, so that the surface of the insulating film can be hydrophobized. Thereby, since moisture can be prevented from being absorbed from the surface of the insulating film, the low dielectric constant of the insulating film can be maintained. Thereby, a semiconductor device having excellent reliability can be obtained.

  According to the present invention, the surface hydrophobization efficiency is improved by using a silane compound having a plurality of RR′R ″ SiO units in one molecule. As a specific effect, a large number of silanol groups generated on the surface in an etching process, an ashing process, etc. react with a plurality of RR′R ″ SiO units present in the silane compound described in the present invention. Can be repaired.

  Hereinafter, the surface hydrophobizing composition, the surface hydrophobizing method, the semiconductor device and the manufacturing method thereof according to the present invention will be specifically described.

1. 1. Surface hydrophobizing composition and surface hydrophobizing method 1-1. Surface hydrophobizing composition 1-1-1. (A) Compound
(A) The compound (a-1) represented by the following general formula (1), the compound (a-2) represented by the following general formula (2), and the compound (a) represented by the following general formula (3) -3) A composition for surface hydrophobization comprising at least one silane compound selected from the group of (3) and (B) an organic solvent.

(1)
^Wherein, R 1, ^{R 2} and ^{R 3} are a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 1 to R ³ is one or zero. ), R ⁴ represents an alkylene group, an alkenylene group, an alkynylene group or a phenylene group. ]

(2)
^Wherein, R 5, ^{R 6} and ^{R 7} are a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 5 to R ⁷ is one or zero. ), R ⁸ represents an alkylene group, an alkenylene group, an alkynylene group or a phenylene group. ]

(3)
^Wherein, R ^{9, R 10,} and ^{R 11} is a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 9 ^{to R 11} is a one or zero. ), M represents Ti or Zr. ]
Compound (a-1): In the above general formula (1), examples of the alkyl group represented by R ^{1 to} R ³ include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, and a tert-butyl group. Group, sec-butyl group, n-pentyl group and the like, preferably having 1 to 5 carbon atoms, these alkyl groups may be chained or branched, and a hydrogen atom is substituted with a fluorine atom or the like May be. Of these, a methyl group and an ethyl group are preferable. Examples of the alkylene group for R ⁴ include an ethylene group and an n-propylene group, preferably 2 to 5 carbon atoms. Examples of the alkenylene group for R ⁴ include a vinylene group and an n-propenylene group. Preferably, it has 2 to 5 carbon atoms, and examples of the alkynylene group represented by R ⁴ include ethynylene and n-propynylene group. These substituents corresponding to R ⁴ may be chained or branched. Preferred compounds as compound (a-1) are bis (trimethylsilyl) malonate, bis (trimethylsilyl) succinate, bis (trimethylsilyl) adipate, bis (trimethylsilyl) itaconate, bis (trimethylsilyl) acetylenedicarboxylate, malonic acid Bis (triethylsilyl) and the like. These may be used alone or in combination of two or more.

Compound (a-2): Examples of the alkyl group for R ^{5 to} R ⁷ include the same alkyl groups as those described above for R ^{1 to} R ³ . Examples of the alkylene group, alkenylene group, and alkynylene group of R ⁸ include the same groups as the alkylene group, alkenylene group, and alkynylene group of R ⁴ described above. Preferred compounds as the compound (a-2) are 1,2-bis (trimethylsiloxy) ethane, 1,3-bis (trimethylsiloxy) -n-propane, 1,2-bis (trimethylsiloxy) cyclobutene, 1,2 -Bis (triethylsiloxy) ethane, and the like. These may be used alone or in combination of two or more.

Compound (a-3): In the above general formula (3), examples of the alkyl group represented by R ^{9 to} R ¹¹ include the same alkyl groups as those described above for R ^{1 to} R ³ . Preferred compounds as the compound (a-3) include tetrakis (trimethylsiloxy) titanium, tetrakis (trimethylsiloxy) zirconium and the like. These may be used alone or in combination of two or more.

  In the composition for hydrophobizing a surface of the present invention, one or two or more of the compounds (a-1), (a-2) and (a-3) can be used.

  The mass of the compound (A) in the surface hydrophobizing composition of the present invention is preferably 1 to 70% by weight, more preferably 3 to 60% by weight, and 5 to 50% by weight. Further preferred. When the mass of the compound (A) in the composition for surface hydrophobization of the present invention is less than 1% by weight, the hydrophobization does not proceed sufficiently. On the other hand, when the mass of the compound (A) exceeds 70% by weight, the composition The storage stability of things deteriorates.

1-1-2. (B) Solvent (B) As the solvent, an aprotic solvent is usually used. (B) When a protic solvent is used as the solvent, the (A) compound may react with the (B) solvent, and the function of hydrophobizing the surface may not be exhibited. However, when the reactivity between the (A) compound and the (B) solvent is low, such as when the (A) compound is an alkoxysilane as described in the above compound (a-2), for example, Protic solvents may be used.

  (B) As the solvent, those exemplified below may be used alone or in combination of two or more. More specifically, the (B) solvent includes a protic solvent and an aprotic solvent. Examples of the protic solvent include alcohol solvents. Examples of the aprotic solvent include ketone solvents, ester solvents, ether solvents, amide solvents, and other aprotic solvents described later.

  Examples of the alcohol solvent include n-butanol, i-butanol, sec-butanol, tert-butanol, n-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-pentanol, 2- Methyl-2-butanol, 3-methoxybutanol, n-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, n-octanol, cyclohexanol, propylene glycol Monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether Ethylene glycol mono-n-hexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytri Examples thereof include glycol and tripropylene glycol monomethyl ether.

  Examples of ketone solvents include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, and methyl-n-hexyl. In addition to ketones, di-i-butyl ketone, trimethylnonanone, cyclohexanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, acetophenone, fenchon, acetylacetone, 2,4-hexanedione, 2 , 4-heptanedione, 3,5-heptanedione, 2,4-octanedione, 3,5-octanedione, 2,4-nonanedione, 3,5-nonanedione, 5-methyl-2,4-hexanedione, 2,2,6,6-tetramethyl-3, - heptanedione, 1,1,1,5,5,5 beta-diketones such as hexafluoro-2,4-heptane dione and the like.

  Examples of ester solvents include diethyl carbonate, ethylene carbonate, propylene carbonate, diethyl carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, and i-acetate. -Butyl, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-acetate -Nonyl, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl acetate Glycol 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, dipropylene Glycol acetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-lactate Examples include amyl, diethyl malonate, dimethyl phthalate, and diethyl phthalate.

  As ether solvents, ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane, dimethyldioxane, ethylene Glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-butyl ether, tetraethylene glycol di-n-butyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether Etc.

  Examples of amide solvents include acetamide, N-methylacetamide, N, N-dimethylacetamide, N-ethylacetamide, N, N-diethylacetamide, N-methylpropionamide, N-methylpyrrolidone, N-formylmorpholine, N- Examples include formylpiperidine, N-formylpyrrolidine, N-acetylmorpholine, N-acetylpiperidine, N-acetylpyrrolidine and the like.

  Other aprotic solvents include aliphatic hydrocarbon solvents such as n-pentane, i-pentane, n-hexane, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane. , N-octane, i-octane, cyclohexane, methylcyclohexane), aromatic hydrocarbon solvents (eg, benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propyl benzene, i-propyl benzene, diethylbenzene, i-butylbenzene, triethylbenzene, di-i-propylbenzene, n-amylnaphthalene, trimethylbenzene), sulfur-containing solvents (for example, dimethyl sulfide, diethyl sulfide, thiophene, tetrahydrothiophene, dimethyl sulfoxide, sulfolane, 1,3 -Pro Sultone), acetonitrile, dimethyl sulfoxide, N, N, N ′, N′-tetraethylsulfamide, hexamethylphosphoric triamide, N-methylmorpholone, N-methylpyrrole, N-ethylpyrrole, N-methyl-3 -Pyrroline, N-methylpiperidine, N-ethylpiperidine, N, N-dimethylpiperazine, N-methylimidazole, N-methyl-4-piperidone, N-methyl-2-piperidone, N-methyl-2-pyrrolidone, 1 , 3-dimethyl-2-imidazolidinone, 1,3-dimethyltetrahydro-2 (1H) -pyrimidinone, and the like.

  Among the aprotic solvents, ketone solvents such as butyl acetate, diethyl ketone, and cyclohexanone are preferable, and propylene glycol monopropyl ether and the like are preferable as the alcohol solvent.

The mass of the (B) solvent in the surface hydrophobizing composition of the present invention is preferably 30 to 99% by weight, more preferably 40 to 97% by weight, and 50 to 95% by weight. Further preferred. When the mass of the (B) solvent in the surface hydrophobizing composition of the present invention is less than 30% by weight, it is difficult to perform uniform coating, while when the mass of the (B) solvent exceeds 99% by weight, It becomes difficult for the composition to remain on the film after spin coating.
1-1-3. (C) Acidic catalyst or basic catalyst The surface hydrophobizing composition of the present invention may further comprise (C) an acidic catalyst or a basic catalyst. In this case, by further including (C) an acidic catalyst or a basic catalyst, when the composition is brought into contact with the surface without any special step, the compound (A) and the group present on the surface The reactivity of can be improved. Thereby, the surface can be hydrophobized in a shorter time.

  Examples of the acidic catalyst include 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, gallic acid Acid, butyric acid, meritic acid, arachidonic acid, shikimic acid, 2-ethylhexanoic acid, oleic acid, stearic acid, linoleic acid, linolenic acid, salicylic acid, benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, benzenesulfone Acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, tartaric acid, maleic anhydride, fumaric acid, itaconic acid, succinic acid, mesaconic acid, Citraconic acid, malic acid, malonic acid, hydrolyzed glutaric acid, hydrolyzed maleic anhydride Objects, and the like hydrolyzate of phthalic anhydride. Examples of inorganic acids include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, and phosphoric acid. Of these, organic acids are preferable in that there is little risk of polymer precipitation or gelation during the reaction, and among these, compounds having a carboxyl group are more preferable, and among them, acetic acid, oxalic acid, maleic acid, formic acid, malonic acid Particularly preferred are hydrolysates of phthalic acid, fumaric acid, itaconic acid, succinic acid, mesaconic acid, citraconic acid, malic acid, malonic acid, glutaric acid and maleic anhydride. These may be used alone or in combination of two or more.

  Examples of basic catalysts include sodium hydroxide, potassium hydroxide, lithium hydroxide, cerium hydroxide, barium hydroxide, calcium hydroxide, pyridine, pyrrole, piperazine, pyrrolidine, piperidine, picoline, ammonia, methylamine, and ethylamine. , Propylamine, butylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicyclo Ochrane, diazabicyclononane, diazabicycloundecene, urea, tetramethylammonium hydroxide, tetraethylan Pyridinium hydroxide, tetrapropyl ammonium hydroxide, tetrabutyl ammonium hydroxide, may be mentioned benzyl trimethylammonium hydroxide, choline, and the like. Among these, ammonia, organic amines, and ammonium hydroxides can be given as preferable examples, and tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrapropylammonium hydroxide are particularly preferable. These may be used alone or in combination of two or more.

  The usage-amount of the said (C) catalyst in the composition for surface hydrophobization of this invention is 0.001-20 weight%.

  The surface hydrophobic composition of the present invention is more suitable as a spin-on composition.

1-2. Method for Using Surface Hydrophobizing Composition The surface hydrophobizing composition of the present invention can be used in contact with the surface of the layer. An example of such a layer is a layer containing silicon atoms as a main constituent element. Layers mainly composed of silicon atoms are widely used in electronic devices such as semiconductor devices, liquid crystal display devices, and organic EL devices. In addition, layers containing silicon atoms as main constituent elements are used not only in the electronics industry but also in fields such as the automobile industry, the optical industry, and the bio industry.

  For example, a layer containing silicon atoms as the main constituent element used as an insulating layer in semiconductor devices comprises oxygen atoms, nitrogen atoms, carbon atoms, hydrogen atoms, fluorine atoms, boron atoms, phosphorus atoms, etc. in addition to silicon atoms. More specifically, examples of such a layer include silicon oxide, silicon oxynitride, silicon nitride, silicon carbide, and an insulating film described later. These layers are an interlayer insulating layer for semiconductor devices, a protective layer such as a surface coat film of a semiconductor device, an intermediate layer of a semiconductor manufacturing process using a multilayer resist, an interlayer insulating layer of a multilayer wiring board, and a protective layer for a liquid crystal display device It is useful for applications such as insulating layers.

  A method for producing a layer containing silicon atoms as a main component is not particularly limited, but representative examples include a CVD method (for example, plasma CVD method) and an SOG method (Spin on Glass). In particular, an insulating film manufactured by the SOG method has been used as an interlayer insulating layer of a more miniaturized semiconductor device. For example, the insulating film contains a silicon atom and can contain at least one element selected from an oxygen atom, a carbon atom, a hydrogen atom, and a nitrogen atom as a constituent element.

  Next, the surface hydrophobization method using the surface hydrophobizing composition of the present invention will be specifically described with reference to FIGS. FIG. 1 is a view schematically showing a semiconductor device manufactured by using the surface hydrophobizing method according to one embodiment of the present invention, and FIGS. 2 to 5 are steps for manufacturing the semiconductor device shown in FIG. It is sectional drawing which shows typically (the surface hydrophobization method of one embodiment of this invention).

  The layer subjected to the surface hydrophobization method of the present invention is excellent in moisture absorption resistance and exhibits a low relative dielectric constant. Therefore, the interlayer for semiconductor devices such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM is used. Useful for applications such as insulating layers, protective layers such as surface coating films for semiconductor devices, intermediate layers in semiconductor manufacturing processes using multilayer resists, interlayer insulating layers for multilayer wiring boards, protective layers and insulating layers for liquid crystal display devices, etc. is there.

  Here, the case where the surface hydrophobizing method of the present invention is applied to the insulating layer included in the semiconductor device will be described, but the layer to which the surface hydrophobizing method of the present invention is applied is not limited to the insulating layer of the semiconductor device. The present invention can be similarly applied to layers included in devices other than semiconductor devices.

  The semiconductor device shown in FIG. 1 includes an insulating layer 20 disposed above a substrate (semiconductor substrate) 10. The insulating layer 20 is provided with a recess 22, and a hydrophobic film 24 is formed on the inner wall 22 a of the recess 22. The hydrophobic film 24 is obtained by bringing the surface hydrophobizing composition of the present invention into contact with the inner wall 22 a of the recess 22. The insulating layer 20 is a layer containing, for example, silicon atoms and oxygen atoms as constituent elements.

  The semiconductor device shown in FIG. 1 can be manufactured by the following steps. First, the insulating layer 20 is formed above the substrate 10 (see FIG. 2). As a method for forming the insulating layer 20, the above-described method can be used.

  Next, after a resist layer R1 having a predetermined pattern is formed on the insulating layer 20 by a known photolithography method, the insulating layer 20 is etched using the resist layer R1 as a mask (see FIG. 3). As the etching, a known method (dry etching or wet etching such as RIE (reactive ion etching)) can be used. At this time, the inner wall 22a of the recess 22 is damaged on the surface by etching. More specifically, the surface of the inner wall 22a of the recess 22 is damaged by the etchant used during etching. As a result, silanol groups (—SiOH) are formed on the surface of the insulating layer 20. In particular, when reactive ion etching is performed, silanol groups are easily formed on the surface of the inner wall 22a of the recess 22 by the reactive ions used as the etchant.

  Next, the resist layer R1 is removed by ashing (see FIG. 4). As the ashing method, for example, plasma ashing using oxygen plasma, ozone ashing using ozone, or wet ashing can be used. Also by this ashing process, the surface of the inner wall 22a of the recess 22 is damaged, and silanol groups are formed on this surface.

  Next, the hydrophobic film 24 is formed on the inner wall 22a of the recess 22 by bringing the surface hydrophobizing composition of the present invention into contact with the surface of the layer (the surface of the inner wall 22a of the recess 22) (see FIG. 5). ). More specifically, the silanol group formed on the surface of the inner wall 22a of the recess 22 reacts with the compound (A) contained in the surface hydrophobizing composition of the present invention, whereby the hydroxyl group (- OH) is replaced with a hydrophobic group to form a hydrophobic membrane 24. That is, the hydrophobic film 24 is obtained by a reaction between the compound (A) and a silanol group on the surface of the inner wall 22 a of the recess 22. By forming this hydrophobic film 24, the surface of the inner wall 22a of the recess 22 is hydrophobized.

  The method for bringing the surface hydrophobizing composition of the present invention into contact with the surface is not particularly limited, and examples thereof include spin coating, spraying, vapor deposition, and dipping.

  Further, by forming the conductive layer 26 in the recess 22, the semiconductor device shown in FIG. 1 is obtained.

  By forming the hydrophobic film 24 in the process shown in FIG. 5, it is possible to prevent moisture from being absorbed into the insulating layer 20 from the surface of the inner wall 22 a of the recess 22. Thereby, since the increase in the moisture in the insulating layer 20 can be prevented, the reliability of the semiconductor device can be maintained. In particular, when the insulating layer 20 is an insulating film, when the moisture in the insulating layer 20 increases, the dielectric constant increases, so that the function as a low dielectric film may not be exhibited. On the other hand, the formation of the hydrophobic film 24 can prevent the moisture in the insulating layer 20 from increasing, so that the function as a low dielectric film can be maintained.

  Here, when forming the hydrophobic film | membrane 24, the process of heating the insulating layer 20 can be further included in the state which contacted the said surface hydrophobization composition of this invention. According to this step, since the reaction between the compound (A) and the silanol group on the surface of the inner wall 22a of the recess 22 can be further promoted, the hydrophobic film 24 can be formed more easily. In this case, the heating step may include a step of heating at a temperature of 1 to 3 steps.

  When the heating process is one stage, for example, the heating can be performed at 150 to 350 ° C. within 15 minutes.

  When the heating process is in two stages, the heating process includes heating the layer (insulating layer 20) at a first temperature and heating the layer at a second temperature higher than the first temperature. Process. For example, the heating reaction at the first stage is performed at the first temperature (any temperature of 50 to 250 ° C.) for 5 minutes or less, and the heating reaction at the second stage is performed at the second temperature (150 to 350 ° C.). The heating can be performed within 10 minutes at any one of the above temperatures.

  When the heating process is in three stages, the heating process includes heating the layer (insulating layer 20) at a first temperature and heating the layer at a second temperature higher than the first temperature. And a step of heating the layer at a third temperature higher than the second temperature. For example, the heating reaction at the first stage is performed at the first temperature (any temperature of 50 to 250 ° C.) for 5 minutes or less, and the heating reaction at the second stage is performed at the second temperature (150 to 300 ° C.). The heating reaction in the third stage can be performed at the third temperature (any temperature of 250 to 350 ° C.) for 5 minutes or less. .

  In this invention, it is preferable to perform the said 1-3 steps of heating processes. In the one-step heating process, it is more preferable to set the temperature so that the reaction between the compound (A) and the silanol group and the evaporation (or decomposition) of the unreacted compound (A) occur simultaneously. On the other hand, in the two-stage heating process, the temperature at which the reaction between the compound (A) and the silanol group occurs in the first-stage heating process and the evaporation (or decomposition) of the unreacted compound (A) occurs in the second-stage heating process. It is more preferable to set to. On the other hand, in the three-stage heating process, the reaction between the compound (A) and the silanol group in the first-stage heating process, and in the second stage heating process, the reaction between the compound (A) and the silanol group. In the heating step, it is more preferable to set the temperature at which evaporation (or decomposition) of the unreacted compound (A) occurs. By setting the heating step as described above, the surface can be made more hydrophobic. In the present invention, it is more preferable to perform the three-step heating process.

  As a heating method, a hot plate, an oven, a furnace, or the like can be used. As a heating atmosphere, it can be performed in the air, a nitrogen atmosphere, an argon atmosphere, a vacuum, a reduced pressure with a controlled oxygen concentration, or the like. In particular, a nitrogen atmosphere is preferable.

  Moreover, after making the above-mentioned (C) acidic catalyst or basic catalyst contact the said surface, you may perform the process which makes the composition for surface hydrophobization of this invention contact the said surface. Alternatively, (C) an acidic catalyst or a basic catalyst may be added to the surface hydrophobizing composition of the present invention containing the compound (A) and the solvent (B), and then the composition may be contacted with the surface. . Thereby, since the reactivity of the (A) compound and the (B) solvent can be further improved, the surface can be hydrophobized at a lower temperature and in a shorter time. Examples of the acidic catalyst or basic catalyst (C) used here include a 5: 4 (molar ratio) mixture of tetramethylammonium hydroxide and maleic acid. As described above, when hydroxysilanes and / or alkoxysilanes are used as the compound (A), a composition obtained by previously mixing the catalyst (C) with the compound (A) and the solvent (B) Can be used.

  Although the case where the surface of the insulating layer 20 is exposed to both etching and ashing has been described here, the surface hydrophobizing method of the present invention is applied to the surface exposed to either etching or ashing. Needless to say, you can. In addition, even if the process is other than etching and ashing, the surface hydrophobization method of the present invention is used when the surface of the insulating layer is chemically and physically damaged by some process (for example, a processing process using plasma). By this, the surface hydrophobizing composition of the present invention can be applied to the surface.

  The processing process using the plasma is not particularly limited, and examples thereof include plasma etching, plasma ashing, plasma CVD, plasma doping, surface treatment using plasma, plasma annealing, and plasma oxidation. . According to the surface hydrophobizing method of the present invention, the surface damaged by such treatment can be hydrophobized.

  According to the method for hydrophobizing a surface of the present invention, by bringing the composition for surface hydrophobizing of the present invention into contact with the surface, the compound (A) in the composition directly reacts (condenses) with the silanol groups on the surface. For this reason, the surface can be reliably hydrophobized.

  In addition, the compound (A) used in the composition for hydrophobizing a surface of the present invention has a relatively small molecular weight, and therefore easily enters the surface of the layer. Thereby, since (A) compound and the silanol group of the surface vicinity react rapidly, the surface can be hydrophobized efficiently.

  The (A) compound does not evaporate before the (A) compound contacts the surface, or does not evaporate before reacting even after contacting. It is also easy to remove from the layer.

1-3. First Semiconductor Device Next, one aspect of the semiconductor device of the present embodiment to which the surface hydrophobizing method of the present invention is applied will be described. FIG. 6 is a cross-sectional view schematically showing the wiring structure 100. The wiring structure 100 functions as a wiring layer and a via layer of the semiconductor device.

  More specifically, the wiring structure 100 includes a conductive layer 90 formed by a dual damascene method. More specifically, the conductive layer 90 includes a via layer 92 and a wiring layer 94 provided continuously on the via layer 92. The via layer 92 is embedded in the first recess 72 provided in the insulating layer (first insulating layer) 120, and the wiring layer 94 is provided in the organic insulating layer (second insulating layer) 220. Embedded in the second recess 74. The installation position of the wiring layer 94 is not particularly limited, and may be a first wiring layer or a second or higher wiring layer. In addition, here, an example in which the surface hydrophobizing method of the present invention is applied to the formation of an insulating layer in a wiring structure formed by a damascene method has been shown. However, the surface hydrophobizing method of the present invention is a damascene method. The present invention is not only applied to a method for manufacturing a wiring structure formed by the above method, but can be applied to a method for manufacturing any layer in a semiconductor device.

  In the semiconductor device shown in FIG. 6, the wiring structure 100 is disposed above the semiconductor substrate 110, disposed on the via layer 92 provided in the first recess 72, disposed on the via layer 92, and second And a wiring layer 94 provided in the recess 74. The first recess 72 is provided in an insulating layer (first insulating layer) 120 disposed above the substrate 10. The second recess 74 is provided in an insulating layer (second insulating layer) 220 disposed above the first insulating layer 120. A hydrophobic film 124 is formed on the inner wall 72 a of the first recess 72. This hydrophobic film 124 is obtained by bringing the above-described composition for hydrophobizing a surface of the present invention into contact with the inner wall 72 a of the first recess 72.

  The first insulating layer 120 is, for example, an MSQ (methylsilsesquioxane) insulating film, and the second insulating layer 220 is, for example, an organic insulating layer. The material of the semiconductor substrate 110 is not particularly limited, but is a compound semiconductor substrate such as a silicon substrate, a sapphire substrate, or GaAs. A second insulating layer 220 is laminated on the first insulating layer 120 with a cap layer 40 interposed therebetween. A diffusion prevention layer 82 is provided on the semiconductor substrate 110. Further, the diffusion prevention layer 82 and the conductive layer 90 are in contact with each other at the bottom surface of the first recess 72. As shown in FIG. 1, the inner walls of the first recess 72 and the second recess 74 may be covered with a barrier layer 80. That is, in this case, the first insulating layer 120 and the via layer 92 are adjacent to each other via the hydrophobic film 124 and the barrier layer 80. The second insulating layer 220 and the wiring layer 94 are adjacent to each other through the barrier layer 80. A cap layer 42 can be provided on the second insulating layer 220.

  Examples of the MSQ insulating film used for the first insulating layer 120 include an SOG film having silicon atoms, oxygen atoms, and carbon atoms as constituent elements.

  The organic insulating layer used for the second insulating layer 220 is selected from, for example, polyarylene, polyarylene ether, polyimide, polybenzoxazole, polybenzobisoxazole, polytriazole, polyphenylquinoxaline, polyquinoline, polyquinoxaline, and the like. An organic insulating film made of polyarylene or polyarylene ether is particularly preferable. In addition, as the second insulating layer 220, one or a combination of two or more of the above organic polymers may be used.

  This wiring structure 100 can be formed, for example, by the following method. 6 to 11 are cross-sectional views schematically showing one manufacturing process of the wiring structure 100.

  First, after forming the diffusion prevention layer 82 above the semiconductor substrate 110, the first insulating layer 120 is formed on the diffusion prevention layer 82 by, for example, the SOG method (see FIG. 7). Next, the stopper layer 40, the second insulating layer 220, and the cap layer 42 are sequentially formed on the first insulating layer 120 (see FIG. 7). Note that the second insulating layer 220 can be formed by coating, for example, in the same manner as the first insulating layer 100. In this case, since a laminated structure can be formed with only one device (spin-on process device), it greatly contributes to an improvement in throughput during semiconductor manufacturing.

  Next, an opening (through hole) 70 that penetrates the first insulating layer 120, the stopper layer 40, the second insulating layer 220, and the cap layer 42 is formed (see FIG. 8). Specifically, first, after forming a resist layer (not shown) on the cap layer 42, a resist layer R10 having a predetermined pattern is formed by a known photolithography process. The resist layer R10 has a pattern for forming the opening 70 (see FIG. 8). Next, using the resist layer R10 as a mask, the first insulating layer 120, the stopper layer 40, the second insulating layer 220, and the cap layer 42 are etched to form an opening 70 (see FIG. 8). Since the first insulating layer 120 is made of an MSQ insulating film, the etching process causes damage to the surface of the inner wall of the opening 70 to generate silanol groups, as shown in FIG. Next, the resist layer R10 is removed by ashing. As described above, the surface of the inner wall of the opening 70 is further damaged by this ashing process.

  Next, a first recess 72 is formed in the first insulating layer 120, and a second recess 74 is formed in the second insulating layer 220 (see FIG. 9). Specifically, first, after forming a resist layer (not shown) on the cap layer 42, a resist layer R11 having a predetermined pattern is formed by a known photolithography process. The resist layer R11 has a pattern for forming the second recess 74. Next, using the resist layer R11 as a mask, the cap layer 42 and the organic insulating layer 220 are patterned by etching using plasma to form the first recess 72 and the second recess 74. Thereafter, the resist layer R11 is removed by ashing or the like. Alternatively, the second insulating layer 220 may be patterned first to form the second recess 74, and then the stopper layer 40 and the first insulating layer 120 may be patterned to form the first recess 72.

  As an etching method of the cap layer 42 and the first insulating layer 120, an etching method using various plasmas (for example, anisotropic plasma etching, reactive plasma etching, inductively coupled plasma etching, ECR plasma etching) or the like is used. Can be used. The etching method for the second insulating layer 220 and the ashing method for the resist layers R10 and R11 are mainly composed of oxygen plasma treatment, ammonia plasma treatment, hydrogen / nitrogen mixed gas plasma treatment, and nitrogen / oxygen mixed gas. A dry etching process can be exemplified.

  Next, the hydrophobic membrane 124 is formed on the inner wall 72a of the first recess 72 by bringing the surface hydrophobizing composition of the present invention into contact with the surface of the inner wall 72a of the first recess 72 (FIG. 10). The procedure in this step can use the surface hydrophobization method of the present invention described above.

  Next, the barrier layer 80 is formed on the inner walls of the first recess 72 and the second recess 74 by using, for example, a CVD method or a sputtering method (see FIG. 11). Subsequently, a conductive layer 90 (see FIG. 6) is formed in the first recess 72 and the second recess 74. Specifically, for example, after a copper seed layer (not shown) is formed by a PVD method, a conductive material 90a is embedded in the first recess 72 and the second recess 74 by a plating method (see FIG. 11). Next, the conductive material 90a is planarized by CMP. As a result, the portion of the conductive material 90a formed above the cap layer 42 is removed, and the conductive layer 90 is obtained (see FIG. 6). That is, the via layer 92 is formed in the first recess 72, and the wiring layer 94 is formed in the second recess 74. Next, a stopper layer 84 is formed on the conductive layer 90 and the cap layer 42 as necessary. Through the above steps, the wiring structure 100 is obtained (see FIG. 6).

  In this wiring structure 100, since the hydrophobic film 124 is formed on the inner wall 72 a of the first recess 72 provided in the first insulating layer 120, moisture is first supplied from the inner wall 72 a of the first recess 72. By entering the insulating layer 120, the hygroscopicity of the first insulating layer 120 can be prevented from increasing. Accordingly, the low dielectric property of the first insulating layer 120 can be maintained, so that a semiconductor device with excellent reliability can be obtained.

1-4. Second Semiconductor Device Next, an aspect of the semiconductor device of the present embodiment to which the surface hydrophobizing method of the present invention is applied will be described. FIG. 12 is a cross-sectional view schematically showing a wiring structure 200 included in the second semiconductor device. The wiring structure 200 functions as a wiring layer and a via layer of the semiconductor device. Note that the semiconductor device illustrated in FIG. 12 is an inorganic second insulating layer instead of the second insulating layer 220 which is an organic insulating layer, as compared with the above-described first semiconductor device (see FIG. 6). The difference is that 320 is provided and the cap layer 44 is provided between the first insulating layer 120 and the second insulating layer 320.

  More specifically, the semiconductor device shown in FIG. 12 includes a wiring structure 200 disposed above the substrate 110. The wiring structure 200 includes a via layer 92 provided in the first recess 72, a via And a wiring layer 94 disposed on the layer 92 and provided in the second recess 74. The first recess 72 is provided in the first insulating layer 120 disposed above the substrate 110. The second recess 74 is provided in the second insulating layer 320 disposed above the first insulating layer 120. Further, a hydrophobic film (first hydrophobic film) 124 is formed on the inner wall 72 a of the first recess 72, and a hydrophobic film (second hydrophobic film) 224 is formed on the inner wall 74 a of the second recess 74. Is formed. The first hydrophobic film 124 is obtained by bringing the above-described surface hydrophobizing composition of the present invention into contact with the inner wall 72a of the first recess 72, and the second hydrophobic film 224 is the above-described one. The surface hydrophobizing composition of the present invention was obtained by contacting the inner wall 72a of the second recess 72.

  The second insulating layer 320 can be made of an MSQ insulating film, for example, like the first insulating layer 120. In this case, the second insulating layer 320 can be manufactured in the same process as the first insulating layer 120.

  The semiconductor device shown in FIG. 12 can be manufactured by the same manufacturing process as the first semiconductor device 120 described above except that the hydrophobic film 224 is formed on the inner wall 74 a of the second recess 74. Hereinafter, the description of the manufacturing process similar to that of the above-described first semiconductor device will be omitted, and only the forming process of the hydrophobic film 224 will be described.

  The surface of the inner wall 74a of the second recess 74 provided in the second insulating layer 320 is provided in the first insulating layer 120 by the etching process and the ashing process performed to form the second recess 74. In addition, the silanol group is generated by being damaged in the same manner as the surface of the inner wall 72a of the first recess 72 (see FIG. 13).

  Next, the surface hydrophobization method of the present invention described above is applied to the surface of the inner wall 74 a of the second recess 74 and also to the surface of the inner wall 74 a of the second recess 74. Thereby, the hydrophobic film 124 is formed on the inner wall 72a of the first recess 72, and the hydrophobic film 224 is formed on the inner wall 74a of the second recess 74 (see FIG. 14). By this step, it is possible to prevent moisture from being absorbed from the inner wall 74a of the second recess 74, and thus it is possible to prevent an increase in hygroscopicity of the second insulating layer 320. Therefore, since the low dielectric property of the second insulating layer 320 can be maintained, a semiconductor device with excellent reliability can be obtained. Moreover, since the surface of the inner wall 72a of the 1st recessed part 72 and the surface of the inner wall 74a of the 2nd recessed part 74 can be processed in the same process, a hydrophobization process can be performed efficiently.

1-5. Features of the Present Invention The features of the present invention will be described in comparison with known techniques relating to the modification of the surface of the layer. Techniques for modifying the surface of the layer are disclosed in, for example, Patent Documents 1 to 4 and Non-Patent Documents 1 and 2 described above.

  Among these, the specification of Patent Document 2 (US Pat. No. 5,550,402) discloses a method for improving the porous structure using ammonium fluoride gas. Further, the specification of Patent Document 4 (US Pat. No. 6,700,200) discloses a method of treating the surface of a layer obtained by the SOG method using ammonium fluoride gas. However, it is necessary to pay close attention to corrosion of containers and pipes by ammonium fluoride itself or by-products, and containers and pipes must be replaced as necessary, which may increase manufacturing costs. high. Further, when the surface of the fluorinated surface is covered with, for example, a barrier metal in a subsequent process, for example, there is a high possibility that a problem occurs in the adhesion with the barrier metal. On the other hand, when the surface is hydrophobized using the composition for hydrophobizing a surface of the present invention, no by-product is generated, so that it is not necessary to pay attention to the container or the like. For this reason, the surface can be easily hydrophobized. Moreover, when the said surface is coat | covered with a barrier metal at a subsequent process, an unexpected side reaction does not arise. Therefore, for example, in the case of including a step of forming a barrier metal film as in the damascene process, the surface hydrophobizing using the surface hydrophobizing composition of the present invention can improve the adhesion between the barrier metal and the surface. Can keep good.

  Patent Document 3 (US Pat. No. 6,548,113) discloses a method of dehydrogenating and alkylating a porous silica film using a halogenated organosilane (for example, TMSI). When halogenated organosilane is used, hydrogen halide is generated after the reaction. Since this hydrogen halide is highly reactive, it may react with other substances to form a halide. When including a step of forming a copper wiring in the manufacturing process of a semiconductor device, when dehydrogenating and alkylating using the method described in Patent Document 3, the process is performed after exposing copper to the bottom of the via. In this case, there is a possibility that a reaction product having a metal corrosive property such as a generated halide adheres to the copper wiring. On the other hand, when the surface is hydrophobized using the composition for hydrophobizing a surface of the present invention, no hydrogen halide is generated, and therefore no unexpected side reaction occurs. Therefore, for example, in the case of including a step of forming a copper wiring as in the damascene process, a reaction product having a metal corrosive property can be obtained by hydrophobizing the surface using the surface hydrophobizing composition of the present invention. Therefore, the electrical connection of the wiring can be kept good.

  Furthermore, Non-Patent Document 1 (Philip G. Clerk, two others, Cleaning and Restoring k Value of Porous MSQ Films, Semiconductor International) , August 2003, pp. 46-52) and Patent Documents 1 and 3 (US Pat. No. 6,383,466, US Pat. No. 6,548,113) disclose a processing method using HMDS (hexamethyldisilazane). However, since HMDS is very hydrophobic and has a relatively large molecular size, it is difficult to diffuse into a portion having a hydrophilic silanol group. On the other hand, since the compound (A) contained in the composition for surface hydrophobization of the present invention is a relatively low molecule and has a lower hydrophobicity than HDMS, it has a hydrophilic silanol group. It can diffuse smoothly. Thereby, a compound (A) can diffuse from the surface of a layer to a deep part, and can react with a silanol group efficiently. Therefore, since the compound (A) can be smoothly diffused into a fine region such as the inner wall of the layer, the surface hydrophobicity can be increased even in the fine region such as the inner wall of the layer.

2. EXAMPLES Next, the present invention will be described more specifically with reference to examples. However, the following description shows the aspect of this invention generally, and this invention is not limited by this description without a particular reason. Moreover, each evaluation in an Example was measured as follows.

2-1. Evaluation method 2-1-1. Blanket Film Evaluation With respect to an insulating film (film 1; insulating layer 420 in FIG. 15) that was fired after being deposited on a silicon substrate (8-inch silicon wafer 310 in FIG. 15) with a film thickness of 100 to 500 [nm], Reactive ion etching (RIE) using NH ₃ gas as an etching gas was performed, and the surface of the insulating film was damaged to produce a film 2 (see FIG. 16). Next, the compositions of Experimental Examples 1 to 3 and Comparative Examples 1 and 2 obtained by the method to be described later are spin-coated on the film 2, respectively, and then subjected to heat treatment on a hot plate to have an insulating film having a hydrophobic film 424. A membrane (membrane 3; see FIG. 17) was prepared.

  Respective dielectric constant (= k) and degassing amount of the insulating film (film 1) after film formation and baking, the insulating film (film 2) after RIE treatment, and the insulating film (film 3) after contact with the composition evaluated. The degassing amount was determined by measuring the amount of water desorbed when heated to 450 ° C. with a temperature-programmed desorption gas analyzer.

  The degassing amount was evaluated according to the following criteria.

A: Desorption moisture amount is 30% or less of insulating film (film 2) after RIE treatment B: Desorption moisture amount is 30% or more of insulation film (film 2) after RIE treatment Also, the dielectric constant is Yokogawa / Hewlett Packard It calculated from the capacity | capacitance value in 10 kHz using the HP16451B electrode and HP4284A precision LCR meter by Corporation | KK.

2-1-2. Pattern Wafer Evaluation A 130 [nm] insulating layer (porous SiOCH) was formed on a silicon wafer (substrate) by the SOG method to produce a copper single damascene structure patterned wafer (see FIG. 15). In FIG. 18, a wiring layer 190 is a copper wiring layer, an insulating layer 520 is a layer containing silicon atoms, oxygen atoms, and carbon atoms as constituent elements, and a substrate 310 is a silicon wafer. Moreover, in FIG. 18, the recessed part 170 is 2-1-1. In the same manner as in the above method, after forming by patterning by etching (RIE), the resist used by ashing was removed. About the obtained pattern wafer, the composition of Experimental Examples 1-3 obtained by the method mentioned later and Comparative Examples 1 and 2 was apply | coated. FIG. 19 is a cross-sectional view schematically showing a copper single damascene wiring structure formed on a patterned wafer after application of the composition. Moreover, the leakage current characteristic of the pattern wafer before apply | coating a composition and the pattern wafer after apply | coating a composition was measured.

  The leakage current was evaluated according to the following criteria.

A: Current value at 2 mV / cm is less than insulating film after RIE treatment B: Current value at 2 mV / cm is more than insulating film after RIE processing 2-2. Experimental Example and Comparative Example Experimental Example 1
3 g of bis (trimethylsilyl) malonate was dissolved in 27 g of cyclohexanone to prepare a 10 wt% composition. This composition was cast by spin coating on an insulating film for blanket film evaluation after etching and an insulating film for pattern wafer evaluation after etching and ashing. Next, these insulating films were heat-treated at 300 ° C. for 5 minutes in a nitrogen atmosphere. Table 1 shows the evaluation results of the insulating film of Experimental Example 1 obtained by the above process.
Experimental example 2
A composition of 15 wt% was prepared by dissolving 4.5 g of 1,2-bis (trimethylsiloxy) ethane in 25.5 g of propylene glycol monopropyl ether. This composition was cast by spin coating on an insulating film for blanket film evaluation after etching and an insulating film for pattern wafer evaluation after etching and ashing. Next, these insulating films were heat-treated on a hot plate at 120 ° C. for 1 minute, and then at 350 ° C. for 1 minute in a nitrogen atmosphere. Table 1 shows the evaluation results of the insulating film of Experimental Example 2 obtained by the above process.
Experimental example 3
Tetrakis (trimethylsiloxy) titanium (6 g) was dissolved in cyclohexanone (24 g) to prepare a 20 wt% composition. This composition was cast by spin coating on an insulating film for blanket film evaluation after etching and an insulating film for pattern wafer evaluation after etching and ashing. Next, these insulating films were heat-treated on a hot plate at 200 ° C. for 3 minutes, and then at 300 ° C. for 3 minutes in a nitrogen atmosphere. Table 1 shows the evaluation results of the insulating film of Experimental Example 3 obtained by the above process.
Comparative Example 1
HMDS 4.5 g (boiling point 126 ° C.) was dissolved in toluene 25.5 g (boiling point 111 ° C.) to prepare a composition having a HMDS concentration of 15 wt%. This composition was cast by spin coating on an insulating film for blanket film evaluation after etching and an insulating film for pattern wafer evaluation after etching and ashing. Next, these insulating films were heat-treated on a hot plate at 80 ° C. for 4 minutes, and then at 250 ° C. for 2 minutes in a nitrogen atmosphere. Table 1 shows the evaluation results of the film of Comparative Example 1 obtained by the above process.
Comparative Example 2
6 g of dimethylchlorosilane (boiling point 36 ° C.) was dissolved in 24 g of toluene (boiling point 111 ° C.) to prepare a composition having a dimethylchlorosilane concentration of 20 wt%. This composition was cast by spin coating on an insulating film for blanket film evaluation after etching and an insulating film for pattern wafer evaluation after etching and ashing. Next, these insulating films were heat-treated on a hot plate at 50 ° C. for 5 minutes and then at 200 ° C. for 2 minutes in a nitrogen atmosphere. Table 1 shows the evaluation results of the film of Comparative Example 2 obtained by the above process.

In Table 1, “dk” = (relative permittivity before applying the composition) − (relative permittivity after applying the composition) is shown.

  According to the insulating films of Experimental Examples 1 to 3, the dielectric constant, degassing amount evaluation, and leakage current characteristics are all good, and the film before composition coating and the film after composition coating are compared. As a result, the relative permittivity decreased significantly. On the other hand, the films obtained in Comparative Examples 1 and 2 have both poor degassing amount evaluation and leakage current characteristics, and the relative dielectric constant is compared between the film before coating the composition and the film after coating the composition. Did not change much. As a result, the insulating film obtained in this experimental example 1 has a low dielectric constant and high moisture absorption resistance, and the composition used in this experimental example 1 has a hydrophobic effect on the surface of the insulating film. confirmed.

It is sectional drawing which shows typically the semiconductor device of one embodiment of this invention. FIG. 4 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 1. FIG. 4 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 1. FIG. 4 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 1. FIG. 4 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 1. It is sectional drawing which shows typically the semiconductor device of one embodiment of this invention. FIG. 7 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 6. FIG. 7 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 6. FIG. 7 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 6. FIG. 7 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 6. FIG. 7 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 6. It is sectional drawing which shows typically the semiconductor device of one embodiment of this invention. FIG. 13 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 12. FIG. 13 is a cross-sectional view schematically showing one manufacturing process of the semiconductor device shown in FIG. 12. In one Example of this invention, it is sectional drawing which shows typically the insulating film (film | membrane 1) after film-forming and baking produced by blanket film evaluation. In one Example of this invention, it is sectional drawing which shows typically the insulating film (film | membrane 2) after RIE created by blanket film evaluation. In one Example of this invention, it is sectional drawing which shows typically the insulating film (film | membrane 3) after RIE created by blanket film evaluation. In one Example of this invention, it is sectional drawing which shows typically the wiring structure body of the copper single damascene structure before the hydrophobic film | membrane formation produced by pattern wafer evaluation. In one Example of this invention, it is sectional drawing which shows typically the wiring structure body of the copper single damascene structure after the hydrophobic film | membrane formation produced by pattern wafer evaluation.

Explanation of symbols

10, 110, 210, 310 Substrate 20, 420, 520 Insulating layer 22, 70, 170 Recess 22a, 72a, 74a, 170a Recess inner wall 24, 124, 424, 524 Hydrophobic film 26, 90 Conductive layer 40 Stopper layer 42 44 cap layer 72 recess (first recess)
74 Concave portion (second concave portion)
80 Barrier layer 82 Diffusion prevention layer 84 Stopper layer 90a Conductive material 92 Via layer 94 Wiring layer 100, 200 Wiring structure 120 Insulating layer (first insulating layer)
124 Hydrophobic membrane (first hydrophobic membrane)
190 Wiring layer 220, 320 Insulating layer (second insulating layer)
224 Hydrophobic membrane (second hydrophobic membrane)
R1, R10, R11 resist layer

Claims (16)

(A) The compound (a-1) represented by the following general formula (1), the compound (a-2) represented by the following general formula (2), and the compound (a) represented by the following general formula (3) -3) A composition for surface hydrophobization comprising at least one silane compound selected from the group of (3) and (B) an organic solvent.

(1)
^Wherein, R 1, ^{R 2} and ^{R 3} are a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 1 to R ³ is one or zero. ), R ⁴ represents an alkylene group, an alkenylene group, an alkynylene group or a phenylene group. ]

(2)
^Wherein, R 5, ^{R 6} and ^{R 7} are a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 5 to R ⁷ is one or zero. ), R ⁸ represents an alkylene group, an alkenylene group, an alkynylene group or a phenylene group. ]

(3)
^Wherein, R ^{9, R 10,} and ^{R 11} is a hydrogen atom, an alkyl group, a vinyl group, an allyl group or a phenyl group (provided ^that the hydrogen atom of R 9 ^{to R 11} is a one or zero. ), M represents Ti or Zr. ] In claim 1,
A composition for hydrophobizing a surface, which is used in contact with the surface of a layer. In claim 2,
The surface hydrophobizing composition, wherein the surface is obtained by etching and / or ashing. In claim 2 or 3,
The layer is a surface hydrophobizing composition containing a silicon atom and containing at least one element selected from an oxygen atom, a carbon atom, a hydrogen atom, and a nitrogen atom as a constituent element. In any of claims 2 to 4,
The composition for surface hydrophobization, wherein the layer is an insulating film.     (C) The composition for surface hydrophobization of Claim 1 which further contains an acidic catalyst or a basic catalyst.   A method of hydrophobizing a surface, comprising heating the layer in a state where the composition is in contact with the surface. In claim 7,
The heating step includes
Heating the layer at a first temperature;
Heating the layer at a second temperature that is higher than the first temperature. In claim 7,
The heating step includes
Heating the layer at a first temperature;
Heating the layer at a second temperature higher than the first temperature;
Heating the layer at a third temperature higher than the second temperature. In any of claims 7 to 9,
(C) A method for hydrophobizing a surface, comprising the step of bringing the composition into contact with the surface after contacting the surface with an acidic catalyst or a basic catalyst.   A semiconductor device comprising a hydrophobic film obtained by the surface hydrophobizing method according to claim 7.   A method for manufacturing a semiconductor device, comprising a step of forming a hydrophobic film by the method for hydrophobizing a surface according to claim 7. A semiconductor device including an insulating layer disposed above a substrate,
The insulating layer is provided with a recess,
A hydrophobic film is formed on the inner wall of the recess,
The said hydrophobic film | membrane is a semiconductor device obtained by making the composition for surface hydrophobization in any one of Claim 1 thru | or 6 contact the inner wall of the said recessed part. A semiconductor device including a wiring structure disposed above a substrate,
The wiring structure is
A via layer provided in the first recess;
A wiring layer disposed on the via layer and provided in the second recess,
The first recess is provided in a first insulating layer disposed above the substrate,
The second recess is provided in a second insulating layer disposed above the first insulating layer,
A hydrophobic film is formed on the inner wall of the first recess,
The said hydrophobic film | membrane is a semiconductor device obtained by making the composition for surface hydrophobization in any one of Claim 1 thru | or 6 contact the inner wall of a said 1st recessed part. A semiconductor device including a wiring structure disposed above a substrate,
The wiring structure is
A via layer provided in the first recess;
A wiring layer disposed on the via layer and provided in the second recess,
The first recess is provided in a first insulating layer disposed above the substrate,
The second recess is provided in a second insulating layer disposed above the first insulating layer,
A first hydrophobic film is formed on the inner wall of the first recess,
A second hydrophobic film is formed on the inner wall of the second recess,
The first hydrophobic film is obtained by bringing the surface hydrophobizing composition according to any one of claims 1 to 6 into contact with the inner wall of the first recess,
The second hydrophobic film is a semiconductor device obtained by bringing the surface hydrophobizing composition according to any one of claims 1 to 6 into contact with an inner wall of the second recess. In claim 14 or 15,
The semiconductor device, wherein the via layer and the wiring layer are integrally formed.

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