KR100508903B1 - Composition for low dielectric film and method for forming low dielectric film - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for forming a low dielectric insulating film of a semiconductor device, and in particular, an organic silane compound containing an organic substance capable of thermal decomposition in an organic solvent, or an organic silane compound containing an organic substance capable of thermal decomposition, and a general silane compound or silane. An organic silicate polymer prepared by mixing oligomers, followed by hydrolysis and condensation reaction by adding water and a catalyst, a coating composition for forming an insulating film for a semiconductor device comprising the same, and forming an insulating film for a semiconductor device further comprising a pore-forming organic material in the composition. The present invention relates to a coating composition for use, a method for producing an insulating film of a semiconductor device to which the composition is applied and cured, and a semiconductor device comprising a low dielectric insulating film produced by the method.

The thermally decomposable organic material covalently bonded to the organosilane compound used in the present invention not only forms pores by itself during the curing process, but also improves the compatibility with the pore-forming material, thereby effectively manufacturing a low dielectric insulating film. . In addition, the low-k dielectric has an effect of easily adjusting fine pores and having excellent insulation.

Description

Composition for forming low dielectric insulating film and method for manufacturing insulating film {COMPOSITION FOR LOW DIELECTRIC FILM AND METHOD FOR FORMING LOW DIELECTRIC FILM}

The present invention relates to a composition for forming a low dielectric insulating film of a semiconductor device, and more particularly, to a method of preparing an organosilicate polymer containing a thermally decomposable organic material, and to forming an insulating film comprising an organosilicate polymer and a pore-forming material prepared therefrom. It relates to a semiconductor composition comprising a coating composition for use, a method for producing an insulating film to which the composition is applied, and an insulating film produced therefrom.

With the recent increase in the degree of integration of semiconductor devices, the line widths of the wires connecting the inside of the devices are rapidly decreasing. In 2003, high density devices using a circuit line width of 0.1 μm are expected to be developed.

In general, the speed of a semiconductor device is proportional to the switching speed of a transistor and the transmission speed of a signal, and the transmission speed of the signal is represented by an RC delay expressed as a product of the resistance of the wiring material and the capacitance of the interlayer insulating film. Is determined. As the degree of integration of semiconductor devices increases, the width between metal lines connecting the inside of the device becomes narrower, and the thickness becomes thinner and the length increases exponentially. The speed on the high density chip is determined by the RC delay on the high density chip rather than the switching speed. . Therefore, in order to manufacture a high speed chip, a low resistance conductor and a low dielectric constant insulating material should be used. In addition, the use of a low dielectric material may not only increase the speed of the semiconductor device, but also may reduce power consumption, and may significantly reduce cross-talk between metal wires.

IBM has recently released a prototype of a semiconductor that does not use traditional aluminum wiring and improves performance by more than 20 percent using copper wiring with high electrical conductivity. On the other hand, semiconductor devices employing low dielectric materials, especially insulating materials having dielectric constants of 2.5 or less, have difficulty in commercialization due to inadequate material development.

In the conventional interlayer insulating materials of semiconductor devices such as IC and LSI, SiO ₂ having a dielectric constant of 4.0 is mostly used, and silicate (F-SiO ₂ ) doped with fluorine as a low dielectric material is applied to some devices. However, in the case of F-SiO ₂ content of more than 6% fluorine is a thermally unstable state has a problem that it is difficult to lower the dielectric constant below 3.5 by this method. Recently, in order to solve these problems, various organic and inorganic polymers having low polarity and thermal stability have 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, and generally have a low glass transition temperature, a significant drop in mechanical strength and a high coefficient of linear expansion compared to SiO ₂ . Organic polymers having such low thermal stability, modulus of elasticity and high linear expansion coefficient can degrade the reliability of the device or the wiring board.

Recently, in order to solve the thermal stability problem of the organic polymer, development of an organosilicate polymer using an alkoxysilane-based compound has been recently underway. This method is a method of forming an organic silicate film through a curing process after hydrolyzing and condensing the organic silane. As such a material methyl or hydrogen silses quoxane is thermally stable at 450 ° C. However, the dielectric constant of the polysilses quoxane also has a relatively high dielectric constant of 2.7 or more and there is a problem that the mechanical properties are not sufficient.

Recently, the organic polymers and organosilicate polymers having a relative dielectric constant of 2.5 to 3.0 have been commercialized in spite of various problems, and studies on ultra low dielectric constants having a relative dielectric constant of 2.5 or less are underway. As a low dielectric material of 2.5 or less, fluorine-containing resins, porous membranes, and the like have been proposed, but materials having sufficient characteristics as interlayer insulating films of LSI have not been developed. The fluorine resin has a low dielectric constant of about 2.0, but since the thermal decomposition temperature is 400 ° C. or less, there is a problem that is not sufficient at the current semiconductor process temperature. Therefore, a porous membrane that introduces pores into a low dielectric material of 2.5 to 3.0 has attracted attention as a technique for achieving a relative dielectric constant of 2.5 or less. Conventional techniques for forming a porous membrane include a method of forming a porous membrane by dispersing the polymer precursor and the polymer particles of US Patent No. 5,700,844 to cure the polymer precursor, and then removing the polymer particles by heating the secondary particles at a high temperature. . However, this method has a problem that it is difficult to form small pores of several nanometers by using polymer particles for pore formation. In addition, the literature (Adv. Mater. 1998, Vol. 10, No. 13, 1049) disperses the organosilicate polymer and the thermally decomposable polymer, the organosilicate is cured at a constant temperature to phase-separate, and the organic polymer is heated by secondary heating at a high temperature. Disclosed is a method for producing a porous superdielectric by removing a. In this method, the degree of phase separation is determined by the interaction between the hydroxy functional group and the organic polymer of the organosilicate polymer.The functional group of the organosilicate is rapidly reduced due to the condensation reaction during the drying and curing processes, making it difficult to control the phase separation. In severe cases, there is a problem that an opaque film can be formed.

US Pat. No. 6,126,733 used a high boiling point solvent instead of organic polymer for pore formation. The above method is a method in which high boiling point solvent is phase separated into nano size during the curing reaction, and the high boiling solvent is evaporated to form pores during the second curing reaction. However, the method has a problem that it is difficult to control the process of phase separation of the high boiling point solvent and the film formation during the gelation process.

In order to solve the above problems, the present invention provides a low-k dielectric material that can be used as a low-k dielectric interlayer insulating film that can reduce the speed and power consumption of the semiconductor device, significantly reducing the mutual interference phenomenon of the metal wiring. It aims to do it.

It is another object of the present invention to provide a method for preparing an organosilicate polymer comprising the low dielectric material, and to provide a coating composition for forming an insulating layer of a semiconductor device, by which the pore is easily formed.

Still another object of the present invention is a method of manufacturing a low dielectric insulating film to which the above-described pore-forming coating composition for forming an insulating film is applied, and is prepared therefrom, which is easy to control fine pores, and has excellent insulation, as well as a film density. It is to provide a semiconductor device comprising a low dielectric insulating film that can significantly lower the.

In order to achieve the above object, the present invention, in the method for producing an organosilicate polymer, an organic silane compound containing an organic substance capable of pyrolysis in an organic solvent, or an organic silane compound containing an organic substance capable of thermal decomposition, and a general silane compound Or after mixing the silane oligomer, water and a catalyst is added to the hydrolysis and condensation reaction provides a method for producing an organosilicate polymer.

The present invention also provides a coating composition for forming a low dielectric insulating film of a semiconductor device comprising an organosilicate polymer prepared by the above method, and a low dielectric insulating film of a semiconductor device to which the composition is applied and cured.

Specifically, in the coating composition for forming an insulating film of a semiconductor device,

a) i) an organosilane compound alone containing an organic substance capable of thermal decomposition; or

  Ii) organosilane compounds containing organic compounds capable of thermal decomposition, and general silanization

      Compound or silane oligomer

  Organosilicate polymer comprising; And

b) organic solvent

It provides a coating composition for forming an insulating film comprising a.

In addition, the composition for forming an insulating film

c) at least one pore-forming material selected from the group consisting of linear organic molecules or polymers, crosslink organic polymers, hyperbranched organic molecules or polymers, and dendrimer type organic materials

It may further include.

In addition, the present invention is a method of manufacturing a low dielectric insulating film of a semiconductor device,

a) iii) an organosilane compound containing thermally decomposable organic substances alone or as a thermal component

      Organosilane compounds containing harmful organic substances, and general silane compounds

      Or organosilicate polymers including silane oligomers;

  Ii) linear organic molecules or polymers, crosslinked organic polymers, hyperbranched

      Group consisting of organic molecules or polymers and dendrimer type organic materials

      Pore forming materials selected from one or more; And

  I) organic solvent

  Providing a coating composition solution for forming an insulating film comprising a;

b) applying the solution of step a) to the substrate of the semiconductor device to form an insulating film

   The step; And

c) drying and baking the insulating film applied in step b).

It provides a method of manufacturing a low dielectric insulating film comprising a and a low dielectric insulating film produced by the manufacturing method.

Hereinafter, the present invention will be described in detail.

The inventors of the present invention, while studying how to easily control the fine pores, and can produce a low-density insulating film, the organic silane compound containing an organic substance that can be thermally decomposed in the organic solvent, or an organic containing an organic substance capable of thermal decomposition As a result of preparing an insulating film-forming composition comprising a silane compound and an organosilicate polymer prepared by mixing a silane compound or a silane oligomer, followed by hydrolysis and condensation reaction by adding water and a catalyst, not only pores are easily formed. In addition, it was confirmed that the insulating film prepared therefrom is easy to control fine pores, has excellent insulation, and can significantly lower the density of the film.

In general, the method of nano-pore formation using the pore-forming material determines the degree of phase separation according to the compatibility between the matrix resin and the pore-forming material, and the number of functional groups in the organosilicate polymer resin decreases and As the environment changes, there is a problem that it is difficult to accurately control the microenvironment and phase separation may occur. In the present invention, in the method for forming pores, pores can be formed by the organothermal decomposition by using an organosilane compound containing an organic substance capable of thermal decomposition. In addition, the present invention may further include a pore-forming material in the organosilicate polymer containing the organic material capable of pyrolysis, thereby lowering the density of the membrane more effectively. At this time, the thermally decomposable organic substance chemically bonded to the silane compound does not undergo hydrolysis and condensation reactions, thereby maintaining compatibility with additional pore-forming materials added during the drying process and the curing process to suppress phase separation, thereby controlling the process of film formation. It is easy and there is an effect that can form small pores.

The pore forming method using the organosilicate polymer containing the thermally decomposable organic material used in the present invention is schematically shown in Scheme 1 below. In addition, a method of forming a pore of an organic / inorganic hybrid composite including an organosilicate polymer containing an organic substance capable of thermal decomposition and a pore forming material added further is shown schematically in Scheme 2 below.

Scheme 1

Scheme 2

As the organosilane compound containing the thermally decomposable organic material used in the present invention, it is preferable to use an organosilane compound in which the thermally decomposable organic material is in the form of a side chain or a bridge between silicon atoms.

The organic material covalently bonded to the silicon atom is a material that can be thermally decomposed at 450 ° C. or lower in a vacuum or inert gas atmosphere. When the film forming composition further includes a pore forming material, a material compatible with the pore forming material is used. It is desirable to.

The method for producing the organosilicate polymer containing the pyrolysable organic silane compound is not particularly limited, and hydrolyzed and condensation reaction with an organosilane compound alone or a general silane compound or a silane oligomer containing an organic material capable of thermal decomposition at 450 ° C. or lower. Polymers can be prepared.

It is preferable to use the compound represented by the following formula (1) or (2) as the organosilane compound capable of thermal decomposition.

[Formula 1]

In the formula of Formula 1,

Each R ¹ is independently hydrogen, fluorine, aryl, vinyl, allyl, or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms,

Each R ² is independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms,

L ¹ is an organic compound capable of thermal decomposition at 450 ° C. or lower, and an organic oligomer or polymer composed of ether compound, ester compound, anhydride compound, carbonate compound, acrylate compound, epoxy compound, or isocyanate compound,

p is an integer from 0 to 2,

q is an integer of 1 to 3,

p + q is an integer of 1-3.

[Formula 2]

In the formula (2),

R ³ and R ⁵ are each independently hydrogen, fluorine, aryl, vinyl, allyl, unsubstituted or substituted with fluorine, straight or branched chain alkyl of 1 to 4 carbon atoms,

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

L ² is an organic compound capable of thermal decomposition at 450 ° C. or lower, an organic oligomer or polymer composed of ether compound, ester compound, anhydride compound, carbonate compound, acrylate compound, epoxy compound, or isocyanate compound,

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

The silane compound containing the thermally decomposable organic material and the general silane compound or silane oligomer commonly used for hydrolysis and condensation reaction are not particularly limited to silane compounds composed of silicon, carbon, oxygen, and hydrogen. One or more compounds selected from the group consisting of compounds represented by the following formula (4) and (5) can be used.

[Formula 3]

In the formula (3),

Each R ⁷ is independently hydrogen, fluorine, aryl, vinyl, allyl or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms,

Each R ⁸ is independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms,

x is an integer of 0-2.

[Formula 4]

In the formula (4),

R ⁹ and R ¹¹ are each independently hydrogen, fluorine, aryl, vinyl, allyl or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms,

R ¹⁰ and R ¹² are each independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms,

M is alkylene or phenylene having 1 to 6 carbon atoms,

y and z are each an integer of 0-2.

[Formula 5]

In the formula (5),

Each R ¹³ is independently hydrogen, fluorine, aryl, vinyl, allyl, or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms,

R ¹⁴ is hydroxy or alkoxy of 1 to 4 carbon atoms on straight or branched chain,

m and n are each an integer of 3-10.

The present invention is a compound selected from the group consisting of a silane compound alone or a compound represented by the formula (3), formula (4), and formula (5) containing a pyrolytic organic material represented by the formula (1) or (2) An organosilicate polymer having a constant molecular weight can be obtained by hydrolysis and polycondensation by adding water and a catalyst in the presence of an organic solvent or in a bulk state.

Mixing order of one or more silane compounds selected from the compounds represented by Formula 1, Formula 2, Formula 3, Formula 4, and Formula 5 used in preparing the organosilicate polymer of the present invention is not particularly limited, After mixing all from the beginning, a hydrolysis and condensation reaction may be performed, and a certain amount of the total amount used may be first hydrolyzed and condensation reaction to raise a certain molecular weight, and then the remaining amount may be further reacted.

The organic solvent used in the preparation of the organosilicate polymer of the present invention is not particularly limited unless the silane compound, water, and catalyst are properly mixed or do not cause hydrolysis and condensation reaction in a phase separation state. Examples thereof include 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, trimethyl benzene, ethyl benzene, or methyl ethyl benzene; Methyl alcohol, ethyl alcohol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, 4-methyl-2-pentanol, cyclo hexanol, methylcyclo hexanol, or glycerol Alcohol solvents such as these; 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, dimethyldioxin, 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, Or ether solvents such as 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 Amide solvents such as amide, N, N-dimethylacetamide, or N, N-diethylacetamide.

The organic solvents used in the hydrolysis and condensation reaction may be used to form a film after removing all or a certain amount of a specific organic solvent, water, and reaction by-products that adversely affect the coating property after the reaction. In addition, according to the purpose, after the reaction, a second amount of a second organic solvent may be added and used as a film-forming organic solvent, or after the addition of the second organic solvent, a specific organic solvent, water, and reaction by-products may be removed and then used to form a film. The organic solvents may be used alone or in combination of two or more thereof.

In the present invention, it is preferable to use a catalyst to promote hydrolysis and condensation reactions. As the catalyst used for the hydrolysis and the condensation reaction, an acid catalyst or a base catalyst may be used. The usable acid catalyst is not particularly limited, for example, 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. The base catalyst that can be used is not particularly limited, but when the insulating film formed is used for a semiconductor device, it is preferable not to include metal ions adversely affecting semiconductor devices such as sodium and potassium, preferably ammonia water or organic amines. Is to use The usable organic amines are not particularly limited, and examples thereof include 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-methylmethyl Alcohol amine, N-ethylmethyl 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 dimethanolamine, N-methyl diethanolamine, N-ethyl diethanolamine, methoxymethylamine, ethoxymethylamine, methoxyethylamine, ethoxyethylamine, aniline, diazabicyclo undecene, pyridine , Pyrrole, piperidine, choline, pyrrolidine, or blood Piperazine and the like. In addition, in the case of using an inorganic base, after removing all metal ions after hydrolysis and condensation reaction, it is used as a coating composition. The acid catalyst or the base catalyst may be used alone or in combination of two or more.

The addition amount of the catalyst can be adjusted according to the reaction conditions, preferably 0.00001 to 2 mol to 1 mol of the total silane compound used. When the added amount exceeds 2 mol per mol of the silane compound, the reaction rate is very fast even at low concentrations, making it difficult to control the molecular weight, and there is a concern that gel may easily occur.

In the method of using the catalyst, the composition may be subjected to step hydrolysis condensation reaction using an acid catalyst or a base catalyst. For example, the hydrolysis condensation reaction may be performed with an acid, followed by reaction with a base, or the hydrolysis condensation reaction may be performed with a base first, followed by reaction with an acid. The condensates may also be used after reacting with an acid catalyst and a base catalyst, respectively.

In the present invention, water is added for hydrolysis of the silane compound. The amount of water used for the hydrolysis of the silane compound is preferably 1 mol or more, more preferably 1 to 50 mol, and most preferably 1.5 mol or more, per mol of the silicon atoms of the total silane compounds used. When water is added in less than 1 mole, hydrolysis condensation reaction does not occur sufficiently, and there is a problem of lowering the mechanical properties of the insulating film. In addition, the method of adding water can be added intermittently or continuously. At this time, the catalyst may be added in an organic solvent in advance, or may be dissolved or dispersed in water when adding water or in advance.

The reaction temperature during the hydrolysis and condensation reaction is preferably from 0 to 100 ℃, more preferably from 15 to 80 ℃. The weight average molecular weight of the hydrolysis-condensation product obtained at this time is 500 or more compared with the molecular weight of polystyrene conversion, and when applied to an insulating film, it is preferable that it is 500-1,000,000.

In order to further lower the density of the insulating film, a predetermined amount of pore forming material may be added to the coating composition for forming an insulating film obtained in the present invention. The pore-forming material may be pyrolyzed at 200 to 450 ° C. A linear organic molecule or polymer, a crosslink organic polymer, a hyperbranched organic molecule or polymer, or a dendrimer may be used. In order to distribute the pores evenly, it is desirable to have compatibility with the thermally decomposable organic material contained in the silane compound. The pore-forming material is preferably contained in 1 to 60% by weight of the coating composition solid content of the insulating film of the present invention, more preferably 2 to 40% by weight.

You may add a fixed amount of components, such as a colloidal silica and surfactant, to the composition for insulating film formation obtained by this invention according to the objective.

The concentration of the total solids of the composition of the present invention is 2 to 60% by weight, preferably 5 to 40% by weight is suitable in consideration of the film thickness and the integrity of the insulating film. The solid content concentration can be adjusted by the type and the amount of the organic solvent.

An insulating film forming composition of the present invention is formed by coating a silicon wafer, SiO ₂ wafer, SiN wafer, a compound semiconductor substrate such as. As the method for forming the insulating film, a spin coating method, an immersion method, a roll coating method, a spray method, or the like can be used, and it is possible to form a film having a predetermined thickness using these methods. In particular, when manufacturing a multilayer circuit interlayer insulating film of a semiconductor device, it is preferable to use a spin coat method.

The thickness of the film can be adjusted by changing the viscosity of the composition and the rotational speed of the spin coater. In general, when the film is used as an interlayer insulating film of a multilayer circuit structure of a semiconductor device, it is appropriate that it is 0.1 to 2 m.

After coating, the organic silicate polymer insulating film having a three-dimensional structure is formed through a drying process and a curing (curing) process, and the organic silicate film may be further cured through the baking process. The drying process usually means including a pre-bake process and a soft-bake process. The organic solvent used during the prebaking process is gradually evaporated, a certain amount of functional groups are crosslinked in the softbaking process, and the remaining functional groups are finally reacted during the firing process. The drying is preferably carried out at a temperature of 30 to 200 ℃, firing at a temperature of 200 ℃ or more, in particular, the firing temperature is preferably carried out at a temperature of 200 to 500 ℃.

A drying process and a baking process can be performed continuously, heating up at a constant speed, and can also be performed intermittently. If carried out intermittently, it is appropriate to carry out the drying and firing processes for 1 minute to 5 hours, respectively. In this case, the heating method may be a hot plate, an oven, a furnace, or the like, and the heating atmosphere may be an inert gas atmosphere such as nitrogen, argon or helium, an oxygen atmosphere such as an oxygen-containing gas (for example, air), or a vacuum or It can be performed under a gas atmosphere containing ammonia and hydrogen. 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, respectively.

After the drying process and the firing process, the surface treatment may be performed to minimize the amount of hydroxyl groups in the insulating film, if necessary. The surface treatment method can be surface-treated by using generally known silylated compounds, such as hexamethyldisilazane, alkylalkoxysilane, or alkylacetoxysilane, or baking in a reducing atmosphere such as hydrogen or a fluorine-containing gas. The silylation treatment method of the insulating film can be immersed or spin-coated in the silylated compound or the silylated compound diluted in a solvent, or can be performed in the vapor atmosphere of the silylated compound. It is preferable to heat.

The film thus obtained has excellent insulation properties, excellent uniformity of the coating film, crack resistance of the coating film, and excellent surface strength of the coating film. Therefore, the interlayer for semiconductor devices such as LSI, system LSI, DRAM, SDRAM, RDRAM, D-RDRAM, etc. It is suitable for use in applications such as an insulating film, 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 preventing film, and the like.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.

EXAMPLE

Example 1

11.4 g of sodium hydride (NaH, 60% by weight) dissolved in mineral oil is dissolved in 100 mL of tetrahydrofuran (THF), and polyethylene glycol monomethyl ether, an organic compound that can be thermally decomposed in 40 mL of tetrahydrofuran (THF), is used. Mn = 350) 20 g solution was slowly added at O ℃. After reacting for 3 hours at room temperature, 20.7 g of allyl bromide was added and reacted overnight at room temperature. After the reaction, the remaining oil was removed by filtration, the silica gel was filtered and filtered several times, and the filtrate was evaporated to remove the remaining reactants to obtain a product.

After putting 0.05 g of Pt / C catalyst into 2 g of the obtained product, 8 g of trimethoxy silane was slowly added at 0 ° C. After raising the temperature to 70 ° C. and reacting overnight, the Pt / C catalyst was removed by filtration and the remaining filtrate was evaporated to obtain an organosilane compound containing polyethylene glycol monomethyl ether, which is a thermally decomposable organic substance.

2.92 g of the organosilane compound containing polyethylene glycol monomethyl ether, the thermally decomposable organic substance obtained above, 19.6 g of methyltriethoxy silane, and 9.9 g of tetraethoxy silane were mixed with 32 g of propylene glycol propylether solvent. Here, the solution which melt | dissolved 0.05 g of malonic acid in 14.5 g of water was dripped slowly. After raising the temperature to 50 ℃, the reaction was allowed to proceed for 8 hours. Evaporation under reduced pressure to remove the by-products and the remaining water after the reaction to obtain a coating composition for forming an insulating film.

Example 2

Except for adding 5% by weight of polyethylene glycol monomethyl ether (Mn = 2000) to the coating composition for forming an insulating film obtained in Example 1 was carried out in the same manner as in Example 1 to obtain a coating composition for forming an insulating film It was.

Comparative Example 1

19.6 g of methyltriethoxy silane and 9.9 g of tetraethoxy silane were mixed with 28 g of a propylene glycol propylether solvent. Here, the solution which melt | dissolved 0.05 g of malonic acid in 14.0 g of water was dripped slowly. After raising the temperature to 50 ℃, the reaction was carried out for 8 hours, and evaporated under reduced pressure to remove the by-products and the remaining water after the reaction to obtain a coating composition for forming an insulating film.

Experimental Example

(Manufacture of insulating film)

The coating composition solution for insulating film formation obtained in Example 1 or 2 and Comparative Example 1 was spin-coated on a silicon wafer, respectively, to obtain a thin film, at a temperature of 250 ° C. under nitrogen atmosphere for 1 hour, and at a temperature of 430 ° C. 1. Curing for a time to prepare an insulating film.

The disappearance of the organic molecules of the insulating film prepared as described above was confirmed by FTIR, the state of the cured film was observed by an optical microscope and an electron microscope, and the change of refractive index was measured by an ellipsometer. The results are shown in Table 1 below.

division Example 1 Example 2 Comparative Example 1 State of insulating film Transparent membrane without phase separation Transparent membrane without phase separation - No pores above 5 nm No pores above 5 nm - Refractive index (n) 1.321 1.299 1.370 Note: Refractive index measured at 632.8 nm.

Through Table 1, the insulating film of Example 1 or 2 according to the present invention was a transparent film without phase separation, and even when observed with an electron microscope, pores of 5 nm or more were not found. In addition, it was confirmed that the insulating film of Example 1 or 2 showed a significantly lower refractive index value than the insulating film of Comparative Example to form a low density film.

Through the above experimental example, when the organic silicate polymer membrane was prepared using the organosilicate polymer and the pore-forming material containing the thermally decomposable organic material of the present invention, there is no phase separation phenomenon during the curing process, and the size of the pores formed by the pyrolysis is electron It can be seen that a low density insulating film having very small pores of several nanometers or less that cannot be observed under a microscope can be formed.

As described above, the insulating film forming composition prepared according to the present invention can be used as a low-k dielectric interlayer insulating film that can reduce the speed and power consumption of semiconductor devices and significantly reduce the mutual interference of metal wiring. In addition, the insulating film to which it is applied is not only easy to control fine pores, but also excellent in insulation, and has an effect of significantly lowering the density of the film.

Claims (7)

a) organic silicate polymers; b) organic solvents; And c) pore-forming substances Including; The a) organosilicate polymer is iii) an organosilane compound represented by the following formula (1) or formula (2) alone; Or ii) an organosilane compound represented by the following Chemical Formula 1, or the following Chemical Formula 2, and a silane compound or a silane oligomer; C) the pore-forming material is a coating composition for forming an insulating film is selected from the group consisting of linear organic molecules or polymers, crosslink organic polymers, hyperbranched organic molecules or polymers, and dendrimer type organic materials: [Formula 1] In the formula of Formula 1, Each R ¹ is independently hydrogen, fluorine, aryl, vinyl, allyl, or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms, Each R ² is independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms, L ¹ is an ether compound capable of thermal decomposition at 450 ° C. or lower, p is an integer from 0 to 2, q is an integer of 1 to 3, p + q is an integer of 1 to 3, [Formula 2] In the formula (2), R ³ and R ⁵ are each independently hydrogen, fluorine, aryl, vinyl, allyl, unsubstituted or substituted with fluorine, straight or branched chain alkyl of 1 to 4 carbon atoms, R ⁴ and R ⁶ are each independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms, L ² is an ether compound capable of thermal decomposition at 450 ° C. or lower, r and s are each an integer of 0-2. delete delete delete delete The method of claim 1, A coating composition for forming an insulating film, wherein the silane compound or silane oligomer is a compound selected from the group consisting of compounds represented by the following Chemical Formula 3, Chemical Formula 4, and Chemical Formula 5 below: [Formula 3] In the formula (3), Each R ⁷ is independently hydrogen, fluorine, aryl, vinyl, allyl or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms, Each R ⁸ is independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms, x is an integer from 0 to 2, [Formula 4] In the formula (4), R ⁹ and R ¹¹ are each independently hydrogen, fluorine, aryl, vinyl, allyl or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms, R ¹⁰ and R ¹² are each independently acetoxy, hydroxy, or straight or branched alkoxy having 1 to 4 carbon atoms, M is alkylene or phenylene having 1 to 6 carbon atoms, y and z are each an integer of 0 to 2, [Formula 5] In the formula (5), Each R ¹³ is independently hydrogen, fluorine, aryl, vinyl, allyl, or unsubstituted or substituted fluorine, straight or branched alkyl having 1 to 4 carbon atoms, R ¹⁴ is hydroxy or alkoxy of 1 to 4 carbon atoms on straight or branched chain, m and n are each an integer of 3-10. a) iii) an organosilane compound containing thermally decomposable organic substances alone or as a thermal component       Organosilane compounds containing harmful organic substances, and silane compounds or       Organosilicate polymers polymerized from silane oligomers;   Ii) linear organic molecules or polymers, crosslinked organic polymers, hyperbranched       Group consisting of organic molecules or polymers and dendrimer type organic materials       Pore forming materials selected from one or more; And   I) organic solvent   Providing a coating composition solution for forming an insulating film comprising a; b) applying the solution of step a) to the substrate of the semiconductor device to form an insulating film    The step; And c) drying and baking the insulating film applied in step b). Method for producing a low dielectric insulating film comprising a.