KR100826208B1 - Method for preparing organic siloxane polymer and method for preparing insulating film using the same - Google Patents

Abstract

The present invention relates to a method for preparing an organosiloxane polymer, and a method for manufacturing an insulating film for a semiconductor using the same, and more specifically, a) i) a silane compound, ii) water, or a mixed solvent of water and an organic solvent, and iii) Mixing the acid catalyst to perform a first reaction at a condition of pH 0.5 to 4; b) further mixing i) water, or a mixed solvent of water and an organic solvent, and ii) a base catalyst after the first reaction, and performing a second reaction under the conditions of pH 9 to 13, and c) the base catalyst. It relates to a method for producing an organosiloxane polymer comprising the step of removing or mixing the acid catalyst to stabilize the reaction solution to pH 2 to 5 and a method for forming an insulating film using the same.

Silane Compound, Acid Catalyst, Base Catalyst, Organosiloxane, Insulation Film, Semiconductor

Description

METHOD FOR PREPARING ORGANIC SILOXANE POLYMER AND METHOD FOR PREPARING INSULATING FILM USING THE SAME}

[Industrial use]

The present invention relates to a method for preparing an organosiloxane polymer, and a method for manufacturing an insulating film using the same, and more particularly, to a method for preparing an organosiloxane polymer having a low dielectric constant and a low refractive index and high mechanical strength by adjusting reaction conditions. A method for producing an insulating film.

[Private Technology]

In recent years, as the degree of integration of semiconductor devices has increased, the wiring density has increased, and the spacing of metal wirings has gradually decreased. As a result, parasitic capacitance between metal wires increases, resulting in a problem that device characteristics cannot be expected using an existing insulating film due to RC delay, cross-talk between metals, and increased power consumption. Introduction of low dielectric materials is essential to the wiring process.

The interlayer insulation materials of semiconductor devices such as conventional integrated circuits (ICs) and high density integrated circuits (LSIs) are mostly SiO ₂ having a dielectric constant of 4.0, and low dielectric materials are silicate doped with fluorine (F-SiO ₂ ). It is applied to some devices. However, in the case of F-SiO ₂ , as the fluorine content increases, it becomes a thermally unstable state, which makes it difficult to lower the dielectric constant below 3.5. Accordingly, various organic and inorganic polymers having low polarity and thermal stability have recently been proposed.

As organic polymers having a low dielectric constant, polyimide resins, polyarylene ether resins, aromatic hydrocarbon resins, and the like are known. Most of these organic polymers have a dielectric constant of 3.2 to 2.6, but the glass transition temperature is low, and thus mechanical strength is significantly lowered and the coefficient of linear expansion is very high compared to SiO ₂ . Such organic polymers having low thermal stability, elastic modulus and high linear expansion coefficient may lower the reliability of the device or the wiring board.

In order to solve the thermal stability problem of the organic polymer as described above, the development of an organosilicate polymer using an alkoxy silane compound is in progress. The organosilicate polymer is prepared by the general method of hydrolyzing and condensing an alkoxy silane compound into an organic polymer having a constant molecular weight.

Polymethylsilsesquioxane or polyhydrogensilsesquioxane, which is an alkoxy silane compound, has a relatively low dielectric constant of 3.0 or less and is thermally stable at 450 ° C. However, polysilsesquioxane is prone to cracking at a thickness of 1 μm or more due to shrinkage stress generated during the curing process, and has a problem that mechanical strength is not sufficient.                         

Therefore, the material having low dielectric constant and low dependence on the calcination temperature is obtained by condensing alkoxy silane in the presence of a base catalyst such as ammonia (JP 1999-340220, 2001-115029) or the unreacted group in the silane. Compositions condensed at a molecular weight (JP 1993-125187) and the like, but in this case it is not preferable because the mechanical properties are not good.

JP 2002-501674 describes a process for synthesizing a precursor under acidic conditions using a small amount of water, forming a sol under basic conditions, and then forming an insulating film in the presence of a base catalyst. In the case of the mechanical strength is bad, the pH of the precursor solution before coating is high, the hydrolysis proceeds, there was a problem that water is generated and the storage property of the precursor solution is inferior.

Therefore, there is a need for further research on a composition for manufacturing an insulating film having higher mechanical properties while maintaining low dielectric constant.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for producing an organosiloxane polymer under a specific condition and manufacturing an insulating film using the same.

In more detail, in order to solve the above problems, the organic silane compound is first reacted under acidic reaction conditions using an acid catalyst, and then secondary reaction is performed under basic reaction conditions using a base catalyst, and the dielectric constant is adjusted again to an acidic condition. It is to provide a method for producing a stable organosiloxane polymer having a low mechanical strength and a method for producing an organosiloxane insulating film using the organosiloxane polymer.

It is also an object of the present invention to provide an organosiloxane polymer prepared according to the method for producing an organosiloxane polymer and a coating composition for forming an insulating film comprising the same.

It is also an object of the present invention to provide an organic siloxane insulating film prepared from the method for producing an organosiloxane insulating film and a semiconductor device comprising the same.

In order to achieve the above object, the present invention comprises the steps of: a) i) a silane compound, ii) water, or a mixed solvent of water and an organic solvent, and iii) an acid catalyst to perform a first reaction at a pH of 0.5 to 4; And b) further mixing i) water, or a mixed solvent of water and an organic solvent, and ii) a base catalyst after the first reaction, to secondary reaction at a pH of 9 to 13; And c) removing the base catalyst or mixing the acidic catalyst to stabilize the reaction solution to pH 2 to 5.

The present invention also comprises the steps of a) i) a silane compound, ii) water, or a mixed solvent of water and an organic solvent, and iii) an acid catalyst to perform a first reaction at a pH of 0.5 to 4; And b) further mixing i) water, or a mixed solvent of water and an organic solvent, and ii) a base catalyst after the first reaction, to secondary reaction at a pH of 9 to 13; And c) removing the base catalyst or mixing the acidic catalyst to stabilize the reaction solution to pH 2-5, to provide an organosiloxane polymer having a weight average molecular weight of 30,000 to 1,500,000 g / mol.

The present invention also provides a coating composition for forming an insulating film comprising the organosiloxane polymer and an organic solvent.

The present invention also includes a) coating and drying the coating composition for forming an insulating film on a substrate; And b) after the drying process, it provides a method for producing an organosiloxane insulating film comprising the step of baking by curing in a nitrogen atmosphere.

The present invention also provides an organic siloxane insulating film prepared according to the method for producing an organic siloxane insulating film and a semiconductor device comprising the same.

Hereinafter, the present invention will be described in more detail.

The present inventors have tried various experiments to obtain an insulating film for a semiconductor device having a low dielectric constant and excellent mechanical strength, and the alkoxy silane compound is reacted in two steps under a specific range of pH conditions to produce an organosiloxane, acidic conditions It was found that an organosiloxane polymer having low dielectric constant and excellent mechanical strength when stored at was obtained.

In addition, when preparing a coating composition for forming an insulating film containing the organosiloxane polymer and applying it to a substrate of a semiconductor device, and drying and firing to form an insulating film, an insulating film for a semiconductor device having low dielectric constant and excellent mechanical strength It was found to be obtained.

In the method for preparing the organosiloxane polymer of the present invention, a silane compound containing silicon, oxygen, carbon, and hydrogen, water or a mixed solvent of water and an organic solvent, and an acid catalyst are mixed to carry out a first reaction at a pH of 0.5 to 4. Step (hereinafter referred to as' acid catalyst reaction ') and after the first reaction, further mixing water or a mixed solvent of water and an organic solvent, and a base catalyst to perform a second reaction under conditions of pH 9 to 13 (hereinafter' base catalyst Reaction '), and the step of removing the base catalyst or further mixing the acid catalyst to stabilize to pH 2-5.

There is no restriction | limiting in particular in the kind of said silane compound, Any silane compound containing silicon, oxygen, carbon, and hydrogen can be used. Preferably, one or more silane compounds may be selected and used from the silane compounds represented by the following Chemical Formulas 1, 2, and 3, dimers prepared from them, or oligomers prepared from them.

[Formula 1]

In Formula 1, R ¹ is hydrogen, fluorine, aryl, vinyl, allyl, or a linear or branched alkyl having 1 to 4 carbon atoms, optionally substituted with fluorine,

R ² is straight or branched alkoxy having 1 to 4 carbon atoms,

p is an integer of 1 to 2.                     

[Formula 2]

In Formula 2, R ³ and R ⁵ are each independently hydrogen, fluorine, aryl, vinyl, allyl, or a linear or branched alkyl having 1 to 4 carbon atoms, unsubstituted or substituted with fluorine,

R ⁴ and R ⁶ are each independently straight or branched alkoxy having 1 to 4 carbon atoms,

M is alkylene having 2 to 3 carbon atoms,

q and r are each an integer of 0-2.

[Formula 3]

In formula (3), R ⁷ is hydrogen, fluorine, aryl, vinyl, allyl or linear or branched alkyl having 1 to 4 carbon atoms, unsubstituted or substituted with fluorine,

R ⁸ is hydrogen, hydroxy, or alkoxy having 1 to 4 carbon atoms on straight or branched chain,

m and n are each an integer of 3-7.                     

The catalyst used in the preparation of the organosiloxane polymer in the present invention serves to promote hydrolysis and condensation of the silane compound. When the acid catalyst is used in the preparation of the organosiloxane polymer, the condensation reaction rate is relatively low, so that a relatively low molecular weight organosiloxane polymer having a molecular weight of several thousand can be prepared, and when the base catalyst is used, the condensation reaction rate is relatively fast. A relatively high molecular weight organosiloxane polymer having a molecular weight of 30,000 or more can be produced.

Therefore, an organosiloxane polymer having a high molecular weight of tens of thousands or more can be produced by carrying out an acid catalyst reaction until the molecular weight grows to about several thousand at the time of preparation of an organosiloxane polymer, and then carrying out a base catalyst reaction.

The acid catalyst that can be used in the present invention is not particularly limited as long as it satisfies the conditions of pH 0.5 to 4. Examples of preferred acid catalysts include hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid, propionic acid, butanoic acid, pentanic acid, hexanoic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, oxalic acid, malonic acid , Sulfonic acid, phthalic acid, fumaric acid, citric acid, maleic acid, oleic acid, methylmalonic acid, adipic acid, p-aminobenzoic acid, or p-tonluenesulfonic acid, and the like, one or two or more of the catalysts may be used simultaneously or stepwise. Can be used as

In addition, the base catalyst that can be used in the present invention is not particularly limited as long as it satisfies the conditions of pH 9 to 13, but since the organosiloxane polymer is used as an insulating film for semiconductor devices, such as sodium, potassium, etc. It is preferable not to include a metal ion which adversely affects. In case of using inorganic base, however, all metal ions should be removed after hydrolysis and condensation reaction.

Preferred examples of the base catalyst may include ammonia, organic amines, alkylammonium hydroxide salts, and more preferably alkylammonium hydroxide salts. Most preferred examples of the base catalyst are methylamine, ethylamine, propylamine, N, N-dimethylamine, trimethylamine, N, N-diethylamine, N, N-dipropylamine, tripropylamine, tetramethylammonium Hydrooxide, Tetraethylammonium Hydrooxide, Methylaminomethylamine, Methylaminoethylamine, Ethylaminomethylamine, Ethylaminoethyl, Methylalcoholamine, Ethylalcoholamine, Propanolamine, N-methylmethylalcoholamine, N-ethylmethyl Alcohol amine, N-methylethyl alcohol amine, N-ethyl ethyl alcohol amine, N, N-dimethyl methyl alcohol amine, N, N-diethyl methyl alcohol amine, N-methyl dimethanol amine, N-ethyl dimethanol amine, N-methyldiethanolamine, N-ethyldiethanolamine, methoxymethylamine, ethoxymethylamine, methoxyethylamine, ethoxyethylamine, aniline, diazabicycloundecene, pyridine, pyrrole, piperidine, Choline, pyrrolidine, or piperazine; Base catalyst can individually or in combination of two or more stages, or use.

The pH adjustment in the base catalyst reaction can be adjusted by removing the acid catalyst used in the previous step and adjusting the pH again, or by adding a base catalyst without removing the acid catalyst used in the previous step. However, since all the acid catalyst is removed before the base catalyst reaction and the base catalyst reaction shows more improved mechanical properties, it is more preferable to adjust the pH by adding the base catalyst again after removing the acid catalyst.                     

When the pH is adjusted to a condition of 2 to 5 for stabilization of the reaction solution after the base catalyst reaction, in the case of the base catalyst having a low boiling point, the pH is lowered by removing the base catalyst by the evaporation method, or otherwise in the case of the previous acid catalyst reaction. The pH is adjusted by mixing the used acid catalyst.

The acid catalyst reaction and the base catalyst reaction necessarily include a predetermined amount or more water, and may be proceeded by adding an organic solvent as necessary.

The amount of water used in the preparation of the organosiloxane polymer in the present invention is preferably a condition in which sufficient hydrolysis can occur. Preferably, in the acid catalyst reaction, the molar ratio of water to 1 mole of the alkoxy group, which is a reactor of the silane compound participating in the reaction, is preferably 0.5 to 10. In the base catalyst reaction, the molar ratio of the silane compound may vary depending on the basicity of the catalyst. It is preferable that the molar ratio of water with respect to 1 mol of alkoxy groups which are reactors is 2-30, and it is more preferable that it is 3-30.

In the acid catalyst reaction, when the molar ratio of water to 1 mole of alkoxy group is less than 0.5, the hydrolysis reaction does not occur sufficiently, and since the alkoxy group is present at 70 mol% or more relative to the reactor, adversely affects the physical properties, and when it is 10 or more, layer separation may occur in the middle of the reaction. . In addition, when the molar ratio of water to 1 mole of the alkoxy group is less than 2 in the base catalyst reaction, a rapid polymerization reaction may occur to form a gel, and when it is 30 or more, the molecular weight of the organosiloxane polymer may not increase sufficiently.

In the present invention, the organic solvent that can be added as needed in the preparation of the organosiloxane polymer is not limited as long as it does not cause a great difficulty in the hydrolysis and condensation reaction of the silane compound, a preferred example of the organic solvent Methyl alcohol, ethyl alcohol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, 4-methyl 2-pentanol, cyclohexanol, methylcyclo hexanol, glycerol, etc. Alcohol solvents; aliphatic hydrocarbon solvents such as n-pentane, i-pentane, n-hexane, i-hexane, 2,2,4-trimethylpentane, cyclo hexane, or methylcyclo hexane; Aromatic hydrocarbon solvents such as benzene, toluene, xylene, xylene, trimethyl benzene, ethyl benzene, or methyl ethyl benzene; Ketone solvents such as acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-i-butyl ketone, diethyl ketone, cyclohexanone, methylcyclohexanone, or acetylacetone; Tetrahydrofuran, 2-methyl tetrahydrofuran, ethyl ether, n-propyl ether, i-propyl ether, n-butyl ether, diglyme, dioxin, dimethyldioxine, ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol dimethyl ether, propylene glycol diethyl Ether solvents such as ether or propylene glycol dipropyl ether; Diethyl carbonate, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, ethyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl acetate, propylene glycol monomethyl ether acetate, propylene Ester solvents such as glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, ethylene glycol diacetate, or propylene glycol diacetate; Or N-methylpyrrolidone, formamide, N-methylformamide, N-ethylformamide, N, N-dimethylformamide, N, N-diethylformamide, N-methylacetamide, N-ethyl Amide solvents such as acetamide, N, N-dimethylacetamide, or N, N-diethylacetamide may be used, and the organic solvent may be used alone or in combination of two or more thereof.

Although the reaction temperature of the hydrolysis and condensation reaction in the production of the organosiloxane polymer is not particularly limited, it is preferable to react at a temperature of 0 to 120 ℃, more preferably at a temperature of 15 to 80 ℃. The reaction temperature may be maintained at a constant temperature during the acid catalyst reaction or the base catalyst reaction, or may be reacted while controlling the temperature intermittently or continuously.

At this time, the molecular weight of the organosiloxane polymer obtained after the acid catalyst reaction and the base catalyst reaction is preferably a weight average molecular weight of 30,000 to 1,500,000 g / mol measured by gel permeation chromatography (GPC).

The organosiloxane polymer prepared as described above has excellent mechanical strength while maintaining low dielectric constant, and is suitable for use as an insulating film for a semiconductor device.

The insulating film for a semiconductor device of the present invention may be prepared from a coating composition for forming an insulating film containing an organosiloxane polymer prepared by the above method.

The coating composition for forming an insulating film includes an organosiloxane polymer and an organic solvent. The organic solvent may be added at the time of preparation of the organosiloxane polymer, or separately after the preparation of the organosiloxane polymer, if necessary.

The type of the organic solvent included in the coating composition for forming the insulating film is not particularly limited, but preferred examples thereof include methyl alcohol, ethyl alcohol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, alcohol solvents such as t-butanol, 4-methyl 2-pentanol, cyclohexanol, methylcyclo hexanol, glycerol; aliphatic hydrocarbon solvents such as n-pentane, i-pentane, n-hexane, i-hexane, 2,2,4-trimethylpentane, cyclo hexane, or methylcyclo hexane; Aromatic hydrocarbon solvents such as benzene, toluene, xylene, xylene, trimethyl benzene, ethyl benzene, or methyl ethyl benzene; Ketone solvents such as acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-i-butyl ketone, diethyl ketone, cyclohexanone, methylcyclohexanone, or acetylacetone; Tetrahydrofuran, 2-methyl tetrahydrofuran, ethyl ether, n-propyl ether, i-propyl ether, n-butyl ether, diglyme, dioxin, dimethyldioxine, ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol dimethyl ether, propylene glycol diethyl Ether solvents such as ether or propylene glycol dipropyl ether; Diethyl carbonate, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, ethyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl acetate, propylene glycol monomethyl ether acetate, propylene Ester solvents such as glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, ethylene glycol diacetate, or propylene glycol diacetate; Or N-methylpyrrolidone, formamide, N-methylformamide, N-ethylformamide, N, N-dimethylformamide, N, N-diethylformamide, N-methylacetamide, N-ethylacetide One or more kinds of amide solvents such as amide, N, N-dimethylacetamide, or N, N-diethylacetamide may be selected and used, and the organic solvent may be added during the preparation of the organosiloxane polymer, or It can be added separately after the preparation of the organosiloxane polymer.

It is preferable that the total organic siloxane polymer solid content concentration of the said coating composition for insulating film formation is 2 to 60 weight%, and it is more preferable that it is 5 to 40 weight%. If the concentration of the solid content is less than 2% by weight, the thickness of the insulating film is thin and practically inferior. If it exceeds 60% by weight, the thickness of the insulating film is too thick and the storage performance deteriorates. Solid content concentration in the coating composition for forming an insulating film may be controlled by the composition and the amount of the organic solvent.

After applying the coating composition for forming an insulating film prepared as described above to a substrate, it can be dried and baked to produce a low dielectric insulating film.

Examples of the substrate used at this time may be a silicon wafer, SiO ₂ wafer, SiN wafer, or a compound semiconductor.

The coating composition for forming the insulating film may be applied to the substrate with a constant thickness by using a spin coating method, dipping method, roll coating method, spray method and the like. In particular, when manufacturing the multilayer circuit interlayer insulating film of a semiconductor device, it is preferable to use the spin coat method.                     

The thickness of the coating composition for forming an insulating film coated in the above manner can be controlled by changing the viscosity of the composition and the rotational speed of the spin coater, but the thickness of the insulating film finally formed through drying and firing is 0.05 to 2 μm. It is preferable to

In the above insulating film manufacturing method, the drying process includes a conventional pre-bake process and a soft-bake process. During the prebaking process, the organic solvent used is gradually evaporated, and during the softbaking process, crosslinking occurs to a certain amount of the functional group.

The prebaking process is a step of removing the used organic solvent, the temperature can be adjusted according to the volatility of the solvent, a temperature of 100 to 250 ℃ is preferred. The prebaking may be carried out only at a constant temperature or at two or more temperatures.

After the drying step is completed, a firing step is carried out to further react the functional groups in an unreacted state to prepare a final insulating film. At this time, the firing process is preferably performed for 1 minute to 5 hours at 350 to 420 ℃, more preferably for 5 minutes to 2 hours.

The drying step and the firing step may be carried out while continuously increasing the temperature at a constant rate, or may be carried out intermittently.

At this time, the heating method is not particularly limited, but a hot plate, an oven, or a furnace may be used, and the heating atmosphere may include an inert gas dust such as nitrogen, argon, helium, oxygen-containing gas (for example, air, etc.), and the like. The same oxygen atmosphere, vacuum state, or a gas atmosphere containing ammonia and hydrogen may be used.

The heating method may be performed by the same heating method as the drying step and the firing step, or may be performed by different methods.

The insulating film of the present invention is a high density integrated circuit (LSI), a system high density integrated circuit (LSI), an interlayer insulating film for semiconductor devices such as DRAM, SDRAM, RDRAM, D-RDRAM, and the like. , A hard mask layer, an etch stop layer, or the like. In addition, it can be used as a protective film and an insulating film for various purposes, for example, it can be used for a protective film such as a semiconductor device surface coating film, an interlayer insulating film of a multilayer wiring substrate, a protective film for a liquid crystal display device, an insulation prevention film, a low refractive film .

Hereinafter, preferred embodiments of the present invention are described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

 Example 1

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

After adding 3.27 g of ethyltrimethoxysilane and 3.82 g of tetraethoxysilane to 6.8 g of tetrahydrofuran, a mixed solution having pH 2 was prepared by slowly adding 11.5 g of 0.01 N nitric acid solution in the presence of nitrogen as an acid catalyst. The mixed solution was allowed to react at room temperature for 30 minutes, and then slowly raised in temperature to react again at 60 ° C. for 16 hours. After the reaction, the reaction solution was cooled to room temperature, 89 g of ethanol and 23.2 g of distilled water were added, and 0.93 g of 25 wt% tetramethyl ammonium hydroxide solution was added to prepare a mixed solution having a pH of 13, and then the temperature was again increased. After raising the temperature to 60 ℃ reacted for 2 hours to prepare an organosiloxane polymer.

After the polymerization reaction was completed, in order to increase the storage stability of the solution, nitric acid was added so that the pH of the reaction solution was 2 to 3, 35 g of propylene glycol monopropyl ether was added, and the remaining reactant was 20 g after distillation under reduced pressure. It was made to be. At this time, by removing the tetramethyl ammonium hydrooxide nitrate remaining in the reaction solution after distillation by filtration, a coating composition for forming an insulating film containing an organosiloxane polymer was obtained.

 (Insulation film production)

The coating composition for insulating film formation prepared as described above was spin-coated onto a silicon wafer, coated, dried on a 100 ° C. hot plate for 2 minutes, heated to 430 ° C. under a nitrogen atmosphere, and fired (cured) for 1 hour. Was prepared.

Example 2

(Preparation of coating composition for insulating film formation containing organic siloxane polymer)

To 6.8 g of an organic solvent, tetrahydrofuran, 3.27 g of ethyltrimethoxy silane and 3.82 g of tetraethoxy silane were added as a silane compound, and then 11.5 g of 0.01 N aqueous nitric acid solution was slowly added as a catalyst in a nitrogen mixture to pH 2 Was prepared. The mixed solution was allowed to react at room temperature for 30 minutes, and then slowly raised in temperature to react at 60 ° C. for 16 hours. After the reaction, the reaction solution was cooled to room temperature, 29.5 g of ethanol was added, and 0.93 g of 25 wt% tetramethyl ammonium hydroxide solution was added thereto to prepare a mixed solution having a pH of 13, and then the temperature was raised to 60 ° C. The reaction was carried out for 2 hours to prepare an organosiloxane polymer.

After the polymerization was completed, nitric acid was added to increase the pH of the reaction solution to 2 to 3 in order to increase the storage stability of the solution, and 35 g of propylene glycol monopropyl ether was added thereto. It was made to be. At this time, by removing the tetramethyl ammonium hydrooxide nitrate remaining in the reaction solution after distillation by filtration, a coating composition for forming an insulating film containing an organosiloxane polymer was obtained. The weight average molecular weight of the obtained organic siloxane polymer is 100,000.

(Insulation film production)

An insulating film was prepared on a silicon wafer in the same manner as in Example 1 using the prepared coating composition for forming an insulating film.

Example 3

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

After adding 3.27 g of ethyltrimethoxysilane and 3.82 g of tetraethoxysilane to 6.8 g of tetrahydrofuran, a mixed solution having pH 2 was prepared by slowly adding 11.5 g of 0.01 N nitric acid solution in the presence of nitrogen as an acid catalyst.

The mixed solution was allowed to react at room temperature for 30 minutes, and then slowly raised in temperature to react again at 60 ° C. for 16 hours.                     

After the reaction, the reaction solution is cooled to room temperature, and diethyl ether and water are added to separate the layers. After nitric acid moved to the water layer and washed with water until the pH of the organic layer became neutral, the mixed tetrahydryfuran and diethyl ether were removed by distillation under reduced pressure. 29.5 g of ethanol and 11.5 g of distilled water were added to the remaining organosiloxane polymer, 0.93 g of 25 wt% tetramethyl ammonium hydroxide solution was added thereto to prepare a mixed solution having a pH of 13, and then the temperature was raised to 60 ° C. The reaction was carried out for a time to prepare an organosiloxane polymer.

After the polymerization reaction was completed, in order to increase the storage stability of the solution, nitric acid was added so that the pH of the reaction solution was 2 to 3, 35 g of propylene glycol monopropyl ether was added, and the remaining reactant was 20 g after distillation under reduced pressure. It was made to be. At this time, tetramethyl ammonium hydrooxide nitrate remaining in the reaction solution after distillation was removed by filtration to obtain a coating composition for forming an insulating film containing an organosiloxane polymer.

 (Insulation film production)

An insulating film was prepared on a silicon wafer in the same manner as in Example 1 using the prepared coating composition for forming an insulating film.

 Comparative Example 1

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

After adding 2.50 g of methyltrimethoxysilane and 3.82 g of tetraethoxysilane to 89 g of ethanol and 34.7 g of distilled water, 0.93 g of 25 wt% tetramethyl ammonium hydrooxide catalyst aqueous solution was slowly added in the presence of nitrogen to prepare a mixed solution of pH 13. Was prepared. The temperature of the mixed solution was raised to 60 ° C. and then reacted for 2 hours to prepare an organosiloxane polymer.

After the reaction was completed, 35 g of propylene glycol propyl ether was added and distilled under reduced pressure so that the remaining reactant was 20 g. After the polymerization was completed, nitric acid was added to increase the pH of the reaction solution to 2 to 3 in order to increase the storage stability of the solution, and 35 g of propylene glycol monopropyl ether was added thereto. It was made to be. At this time, tetramethyl ammonium hydrooxide nitrate remaining in the reaction solution after distillation was removed by filtration to obtain a coating composition for forming an insulating film containing an organosiloxane polymer.

 (Insulation film production)

An insulating film was formed on the silicon wafer in the same manner as in Example 1 using the prepared coating composition for forming an insulating film.

Comparative Example 2

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

2.50 g of methyltrimethoxy silane and 3.82 g of tetraethoxysilane were added to 29.5 g of ethanol and 11.5 g of distilled water, and then 0.93 g of 25 wt% tetramethyl ammonium hydrooxide catalyst aqueous solution was slowly added in the presence of nitrogen to prepare a mixed solution having a pH of 13 Prepared. The temperature of the mixed solution was raised to 60 ° C. and then reacted for 2 hours to prepare an organosiloxane polymer.                     

After the polymerization was completed, nitric acid was added to increase the pH of the reaction solution to 2 to 3 in order to increase the storage stability of the solution, and 35 g of propylene glycol monopropyl ether was added thereto. It was made to be. At this time, tetramethyl ammonium hydrooxide nitrate remaining in the reaction solution after distillation was removed by filtration to obtain a coating composition for forming an insulating film containing an organosiloxane.

(Insulation film production)

An insulating film was prepared on a silicon wafer in the same manner as in Example 1 using the prepared coating composition for forming an insulating film.

Comparative Example 3

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

After adding 3.27 g of ethyltrimethoxysilane and 3.82 g of tetraethoxysilane to 6.8 g of tetrahydrofuran, 11.5 g of 0.01 N nitric acid aqueous solution was slowly added in the presence of nitrogen to prepare a mixed solution having a pH of 2. After reacting for 30 minutes at room temperature, the temperature was gradually raised again and reacted at 60 ° C. for 16 hours. After the reaction was completed, 30 g of propylene glycol propyl ether was added and the resultant was distilled under reduced pressure so that the remaining reactant was 11.5 g, thereby preparing a coating composition for forming an insulating film.

 (Insulation film production)

An insulating film was prepared on a silicon wafer in the same manner as in Example 1 using the prepared coating composition for forming an insulating film.                     

[Comparative Example 4]

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

To 6.8 g of an organic solvent, tetrahydrofuran, 3.27 g of ethyltrimethoxy silane and 3.82 g of tetraethoxy silane were added as a silane compound, and then 11.5 g of 0.01 N aqueous nitric acid solution was slowly added as a catalyst in a nitrogen mixture to pH 2 Was prepared.

The mixed solution was allowed to react at room temperature for 30 minutes, and then slowly raised in temperature to react at 60 ° C. for 16 hours.

After the reaction, the reaction solution was cooled to room temperature, 29.5 g of ethanol was added, and 0.93 g of 25 wt% tetramethyl ammonium hydroxide solution was added thereto to prepare a mixed solution having a pH of 13, and then the temperature was raised to 60 ° C. The reaction was carried out for 2 hours to prepare an organosiloxane polymer. Again 35 g of propylene glycol monopropyl ether was added to the reaction, which was then gelled upon distillation under reduced pressure.

[Comparative Example 5]

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

To 6.8 g of an organic solvent, tetrahydrofuran, 3.27 g of ethyltrimethoxy silane and 3.82 g of tetraethoxy silane were added as a silane compound, and then 1.04 g of 0.1 N aqueous nitric acid solution was slowly added as a catalyst to pH 2 A mixed solution was prepared. The amount of water used at this time is 0.45 mol to 1 mol of alkoxy groups of the silane compound. The mixed solution was allowed to react at room temperature for 30 minutes, and then slowly raised in temperature to react at 60 ° C. for 16 hours.                     

After the reaction, the reaction solution was cooled to room temperature, 29.5 g of ethanol was added, and 0.93 g of 25 wt% tetramethyl ammonium hydrooxide aqueous solution was added to prepare a mixed solution having a pH of 13, and the temperature was raised to 60 ° C. Gelled in the process.

Comparative Example 6

(Preparation of Coating Composition for Insulating Film Forming Organic Oxide Polymer)

To 6.8 g of propylene glycol monopropyl ether, 3.27 g of ethyltrimethoxy silane and 3.82 g of tetraethoxy silane were added as a silane compound, and then 1.04 g of 0.1 N aqueous nitric acid solution was slowly added in the presence of nitrogen and mixed at pH 2 as a catalyst. The solution was prepared. The amount of water used at this time is 0.45 mol to 1 mol of alkoxy groups of the silane compound.

The mixed solution was allowed to react at room temperature for 30 minutes, and then slowly raised in temperature to react at 60 ° C. for 16 hours. After the reaction, the reaction solution was cooled to room temperature.

After adding 10 g of ethanol, 0.93 g of a 25 wt% tetramethyl ammonium hydroxide aqueous solution was added to prepare a mixed solution having a pH of 13, and allowed to stand overnight to stabilize.

(Insulation film production)

 The coating composition for insulating film formation prepared as described above was spin coated onto a silicon wafer, and was then wetted for 3 minutes in a chamber having a relative humidity of 75% (temperature is 30 ° C.), followed by drying for 2 minutes on a hot plate at 100 ° C. I was. It heated up to 430 degreeC in nitrogen atmosphere, and baked (hardened) for 1 hour, and prepared the insulating film.

The mechanical strength and dielectric constant of the polyorganosiloxane insulating films prepared according to Examples 1, 2, and 3 and Comparative Examples 1, 2, 3, and 6 were measured by the following method, and the results are shown in Table 1 below.

A) Mechanical strength-After the insulating film was coated on the silicon wafer by spin coating and cured, it was measured by a continuous stiffness (CS) method using a nanoindenter of MTS.

B) Dielectric constant-After hardening by spin-coating an insulating film on a silicon wafer by a metal insulator semiconductor (MIS) method, Al was deposited on the insulating film and measured at 1 MHz.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 6 burglar 8.6 5.5 6.3 7.3 4.4 12.0 3.2 permittivity 2.51 2.25 2.25 2.51 2.25 3.1 2.65

In Table 1, the organic siloxane insulating film prepared by Examples 1 and 2 prepared in accordance with the present invention can be confirmed that the mechanical strength is superior to Comparative Examples 1 and 2 having the same dielectric constant, respectively.

In addition, it can be seen that the insulating film of Example 3, which had been subjected to the reaction under basic conditions with the acid catalyst removed, showed better strength than the insulating film of Example 2.

However, in the case of Comparative Example 3 using only an acid catalyst, low dielectric constant could not be realized, and in Comparative Example 4 in which the pH of the solution was not acidified under the condition of 2 to 5 after acidic reaction and basic reaction, gelation or storage property was intermediate in the reaction. Very bad In the case of Comparative Example 5 in which the amount of water used during the reaction was less than 0.5 mole with respect to 1 mole of the alkoxy group, gelation occurred at elevated temperature in the middle of the base reaction, and in Comparative Example 6, in which the compound was obtained by lowering the reaction temperature, the mechanical properties were inferior. lost.

Therefore, it can be seen that the insulating film formed of the polyorganosiloxane polymer prepared according to the production method of the present invention has a low dielectric constant and excellent mechanical strength.

The organosiloxane polymer prepared by the manufacturing method of the present invention has a low dielectric constant and excellent mechanical strength, such as a large scale integration (LSI), a system high density integrated circuit (LSI), DRAM, SDRAM, RDRAM, D-RDRAM, and the like. It can be used for interlayer insulating film for semiconductor device, capping layer for semiconductor device, hard mask layer, etch stop layer, etc. In addition, protective film such as semiconductor device surface coating film It can also be used as a protective film and an insulating film, such as an interlayer insulating film of a multilayer wiring substrate, a protective film for a liquid crystal display element, an insulation preventing film, a low refractive film, and the like.

Claims (16)

a) i) silane compound,    ii) water or a mixed solvent of water and an organic solvent, and    iii) acid catalyst Mixing the first reaction under the conditions of pH 0.5 to 4; b) after the first reaction    i) water or a mixed solvent of water and an organic solvent, and    ii) base catalyst Further mixing the second reaction under conditions of pH 9 to 13; And c) stabilizing the reaction solution to pH 2 to 5 by removing the base catalyst or by mixing the acid catalyst Method for producing an organosiloxane polymer comprising a. The silane compound according to claim 1, wherein the silane compound is one selected from the group consisting of silane compounds represented by the following Chemical Formulas 1, 2, and 3, dimers prepared from them, oligomers prepared from them, and mixtures thereof. The manufacturing method of the organosiloxane polymer which is the above silane compound. [Formula 1]

In Formula 1, R ¹ is hydrogen, fluorine, aryl, vinyl, allyl, or a linear or branched alkyl having 1 to 4 carbon atoms, optionally substituted with fluorine, R ² is straight or branched alkoxy having 1 to 4 carbon atoms, p is an integer of 1 to 2. [Formula 2]

In Formula 2, R ³ and R ⁵ are each independently hydrogen, fluorine, aryl, vinyl, allyl, or a linear or branched alkyl having 1 to 4 carbon atoms, unsubstituted or substituted with fluorine, R ⁴ and R ⁶ are each independently straight or branched alkoxy having 1 to 4 carbon atoms, M is alkylene having 2 to 3 carbon atoms, q and r are each an integer of 0-2. [Formula 3]

In formula (3), R ⁷ is hydrogen, fluorine, aryl, vinyl, allyl or linear or branched alkyl having 1 to 4 carbon atoms, unsubstituted or substituted with fluorine, R ⁸ is hydrogen, hydroxy, or alkoxy having 1 to 4 carbon atoms on straight or branched chain, m and n are each an integer of 3-7. According to claim 1, wherein the acid catalyst is hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid, propionic acid, butanoic acid, pentanic acid, hexanoic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trichloroacetic acid, An organosiloxane polymer which is at least one acid catalyst selected from the group consisting of oxalic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, maleic acid, oleic acid, methylmalonic acid, adipic acid, p-aminobenzoic acid, and p-toluenesulfonic acid Manufacturing method. The method of claim 1, wherein the base catalyst is at least one base catalyst selected from the group consisting of ammonia, organic amines, and alkylammonium hydroxides. The method of claim 1, wherein the base catalyst is methylamine, ethylamine, propylamine, N, N-dimethylamine, trimethylamine, N, N-diethylamine, N, N-dipropylamine, tripropylamine, tetra Methyl ammonium hydrooxide, tetraethylammonium hydrooxide, methylaminomethylamine, methylaminoethylamine, ethylaminomethylamine, ethylaminoethyl, methylalcoholamine, ethylalcoholamine, propanolamine, N-methylmethylalcoholamine, N- Ethyl methyl alcohol amine, N-methyl ethyl alcohol amine, N-ethyl ethyl alcohol amine, N, N-dimethylmethyl alcohol amine, N, N-diethyl methyl alcohol amine, N-methyl dimethanol amine, N-ethyl dimethanol Amine, N-methyl diethanolamine, N-ethyl diethanolamine, methoxymethylamine, ethoxymethylamine, methoxyethylamine, ethoxyethylamine, aniline, diazabicycloundecene, pyridine, pyrrole, piperi Dine, choline, pyrrolidine, and piperazine in the group 1. A method for producing a organosiloxane polymer of two or more base catalyst. The method for preparing an organosiloxane polymer according to claim 1, wherein the molar ratio of water to 1 mole of an alkoxy group which is a reactor of the silane compound in the first reaction step is 0.5 to 10. The method for producing an organosiloxane polymer according to claim 1, wherein the molar ratio of water to 1 mole of an alkoxy group which is a reactor of the silane compound in the second reaction step is 2 to 30. The method of claim 1, wherein the first reaction step and the second reaction step is carried out at a temperature of 0 to 120 ℃. The method of claim 1, wherein the organic solvent is methyl alcohol, ethyl alcohol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, 4-methyl 2-pentanol, cyclohexa Nol, methylcyclo hexanol, glycerol, n-pentane, i-pentane, n-hexane, i-hexane, 2,2,4-trimethylpentane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, xylene, Trimethyl benzene, ethyl benzene, methyl ethyl benzene, acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-i-butyl ketone, diethyl ketone, cyclohexanone, methylcyclohexanone, Acetylacetone, tetrahydrofuran, 2-methyl tetrahydrofuran, ethyl ether, n-propyl ether, i-propyl ether, n-butyl ether, diglyme, dioxin, dimethyldioxine, ethylene glycol monomethyl ether , Ethylene glycol monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol dimethyl ether Le, ethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, diethyl carbonate, methyl acetate, Ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, ethyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene Glycol monopropyl ether acetate, ethylene glycol diacetate, propylene glycol diacetate, N-methylpyrrolidone, formamide, N-methylformamide, N-ethyl formamide, N, N-dimethylformamide, N, N- Diethyl Name amide, N- dimethylacetamide, N- ethyl acetamide, N, N- dimethylacetamide, and N, N- di least one member manufacturing method of the organic siloxane polymer is selected from the group consisting of ethyl acetamide. delete delete delete delete delete delete delete