JP4802120B2 - Insulating film forming composition and insulating film manufacturing method - Google Patents

Description

  The present invention relates to an insulating film forming composition and an insulating film manufacturing method, and more particularly, can form a coating film having an appropriate uniform thickness as an interlayer insulating film material in a semiconductor element or the like, and has a dielectric constant. The present invention relates to an insulating film forming composition useful for forming an insulating film having excellent characteristics and the like, and an insulating film manufacturing method.

Conventionally, a silica (SiO ₂ ) film formed by a vacuum process such as a vapor deposition (CVD) method is frequently used as an interlayer insulating film in a semiconductor element or the like. In recent years, for the purpose of forming a more uniform interlayer insulating film, a coating type insulating film called a SOG (Spin on Glass) film containing a hydrolysis product of tetraalkoxylane as a main component has been used. It has become. In addition, with high integration of semiconductor elements and the like, an interlayer insulating film having a low dielectric constant, which is mainly composed of polyorganosiloxane called organic SOG, has been developed.

However, even the CVD-SiO ₂ film showing the lowest dielectric constant among the inorganic material films has a relative dielectric constant of about 4. The relative dielectric constant of the SiOF film, which has been recently studied as a low dielectric constant CVD film, is about 3.3 to 3.5. This film has high hygroscopicity, and the dielectric constant increases while being used. There is a problem of doing.

Under such circumstances, as an insulating film material excellent in insulation, heat resistance, and durability, a method is known in which a high boiling point solvent or a thermally decomposable compound is added to organopolysiloxane to form voids and lower the dielectric constant. ing. However, the porous film as described above has problems such as a decrease in mechanical strength and an increase in dielectric constant due to moisture absorption even if the dielectric constant characteristics decrease due to porosity. In addition, since vacancies connected to each other are formed, copper used for wiring diffuses into the insulating film.
On the other hand, an attempt to obtain a film having a low refractive index and a low density by applying a solution obtained by adding a low molecular weight cage compound to an organic polymer is also known. However, this method is insufficient in reducing the refractive index and dielectric constant.

JP 2000-334881 A

  Accordingly, an object of the present invention relates to a composition for forming an insulating film and an insulating film manufacturing method for solving the above-described problems, and more particularly, suitable for use as an interlayer insulating film in a semiconductor element device or the like. An object of the present invention is to provide a composition for forming an insulating film and a method for manufacturing the insulating film, which are capable of forming a film having a uniform thickness and are excellent in film characteristics such as dielectric constant and Young's modulus.

Ａ）３，３’−（オキシジ１，４−フェニレン）ビス（２，４，５−トリフェニルシクロペンタジエノン）、および１，３，５−トリス（フェニルエチニル）ベンゼンから合成したポリマー、
Ｂ）テトラビニルシランから合成したポリマー、
Ｃ）１，３−ジエチニルアダマンタンおよび１，３，５−トリイソプロピルベンゼンから合成したポリマー、
（２）前記シルセスキオキサン化合物（Ｉ−ｄ）を重合させた高分子化合物の、ＧＰＣで測定したポリスチレン換算重量平均分子量が５万〜５０万であり、ポリスチレン換算数平均分子量が１．５万〜２０万であることを特徴とする前記（１）に記載の絶縁膜形成用組成物。
（３）前記（１）または（２）に記載の絶縁膜形成用組成物を基板上に塗布した後、硬膜することを特徴とする絶縁膜製造方法。 It has been found that the above object of the present invention can be achieved by the following means.
(1) At least selected from a polymer compound obtained by polymerizing the following compound ( Id) as a cage-type silsesquioxane compound having two or more unsaturated groups as substituents, the following A) to C): A composition for forming an insulating film, comprising a heat-resistant organic polymer compound having any carbon-carbon unsaturated bond and an organic solvent.

A) a polymer synthesized from 3,3 ′-(oxydi1,4-phenylene) bis (2,4,5-triphenylcyclopentadienone) and 1,3,5-tris (phenylethynyl) benzene,
B) a polymer synthesized from tetravinylsilane,
C) a polymer synthesized from 1,3-diethynyladamantane and 1,3,5-triisopropylbenzene,
(2) The polymer compound obtained by polymerizing the silsesquioxane compound (Id) has a polystyrene equivalent weight average molecular weight measured by GPC of 50,000 to 500,000 and a polystyrene equivalent number average molecular weight of 1.5. The composition for forming an insulating film as described in (1) above, wherein the composition is 10,000 to 200,000 .
(3) A method for producing an insulating film, comprising applying the composition for forming an insulating film according to (1) or (2) on a substrate, and then forming a hard film.

  ADVANTAGE OF THE INVENTION According to this invention, the composition for insulating film formation excellent in film | membrane characteristics, such as a dielectric constant and a Young's modulus, and an insulating film manufacturing method suitable for using as an interlayer insulation film in a semiconductor device etc. can be provided.

The present invention relates to the composition for forming an insulating film and the method for producing an insulating film according to the above (1) to ( 3 ), and other matters are also described in this specification for reference.
Hereinafter, the composition for forming an insulating film of the present invention (hereinafter also referred to as a composition) includes a polymer compound obtained by polymerizing a cage silsesquioxane compound having two or more unsaturated groups as substituents.
The cage-type silsesquioxane compound having two or more unsaturated groups as a substituent (hereinafter also referred to as compound (I)) is, for example, m RSi (O _0.5 ) ₃ units (m is 8 to 16). Each of R is independently a non-hydrolyzable group, and at least two of R are groups containing a carbon-carbon unsaturated bond), Examples thereof include a compound that shares an oxygen atom and is linked to another unit to form a cage structure (hereinafter also referred to as compound (I ′)).
From the viewpoint of the dielectric constant lowering effect, m in the compound (I ′) is preferably 8, 10, 12, 14, or 16, and more preferably 8, 10, or 12 from the viewpoint of availability.

  Here, the cage structure refers to a molecule whose volume is determined by a plurality of rings formed of covalently bonded atoms, and a point located within the volume cannot leave the volume without passing through the ring.

  Examples of the cage structure represented by compound (I) include the following. The free bond in the following represents the position where R is bonded.

In compound (I), each R independently represents a non-hydrolyzable group.
Here, the non-hydrolyzable group is a group that remains at 95% or more when contacted with 1 equivalent of neutral water at room temperature for 1 hour, but remains at 99% or more under these conditions. Is preferred.
At least two of R are groups containing a carbon-carbon unsaturated bond. Examples of non-hydrolyzable groups for R include alkyl groups (methyl, t-butyl, cyclopentyl, cyclohexyl, etc.), aryl groups (phenyl, 1-naphthyl, 2-naphthyl, etc.), vinyl groups, ethynyl groups, allyl groups. And silyloxy groups (trimethylsilyloxy, triethylsilyloxy, t-butyldimethylsilyloxy) and the like.

Of the groups represented by R, at least two are preferably groups containing a vinyl group or an ethynyl group, but at least two are more preferably vinyl groups. When the group represented by R includes a vinyl group or an ethynyl group, the vinyl group or ethynyl group is preferably bonded to the silicon atom to which R is bonded, directly or through a divalent linking group. Examples of the divalent linking group include-[C (R ¹¹ ) (R ¹² )] _k- , -CO-, -O-, -N (R ¹³ )-, -S-, -O-Si (R ¹⁴ ) (R ¹⁵ ) —, and divalent linking groups formed by arbitrarily combining these. (R ^{11 to} R ¹⁵ each independently represents a hydrogen atom, a methyl group, an ethyl group, or a phenyl group, and k represents an integer of 1 to 6), among them — [C (R ¹¹ ) (R ¹² )] _k- , -O-, -O-Si (R ¹⁴ ) (R ¹⁵ )-or a divalent linking group formed by arbitrarily combining these is preferable.
In compound (I), the vinyl group or ethynyl group is preferably directly bonded to the silicon atom to which R is bonded.
More preferably, at least two vinyl groups out of R in compound (I) are directly bonded to the silicon atom to which R is bonded, and at least half of R in compound (I) are all vinyl groups. It is particularly preferred that all R are vinyl groups.

  Specific examples of compound (I) include, but are not limited to, the following.

  Compound (I) may be a commercially available product or may be synthesized by a known method.

  It is also preferable that R in the compound (I) of the present invention is a group represented by the following general formula (II). In this case, the compound represented by the following general formula (III) and the following general formula (IV) It can synthesize | combine by making the compound made to react.

(R ¹ ) ₃ —Si—O— (II)
[MO-Si (O _0.5 ) ₃ ] _m (III)
(R ¹ ) ₃ —Si—Cl (IV)

  The compound represented by the general formula (III) can be synthesized according to the method described in, for example, Angew. Chem. Int. Ed. Engl. 1997, 36, No. 7, 743-745.

In these formulas, each R ¹ independently represents a non-hydrolyzable group. Specific examples of the non-hydrolyzable group represented by R ¹ include an alkyl group, an aryl group, a vinyl group, and an ethynyl group. can give. m and R ¹ are the same as in compound (I ′) and general formula (II). M represents a metal atom (for example, Na, K, Cu, Ni, Mn) or an onium cation (for example, tetramethylammonium). When M is a polyvalent metal atom, it means a form in which a plurality of —O—Si (O _0.5 ) ₃ is bonded to the polyvalent metal atom M.

The reaction between the compound represented by the general formula (III) and the compound represented by the general formula (IV) is carried out, for example, in a solvent by combining the compound represented by the general formula (III) and the general formula (III) 1 to 100 times mol of the compound represented by the general formula (IV) of the number of Si-OM groups contained in the compound represented by formula (IV) is added, and the stirring is usually performed at 0 to 180 ° C. for 10 minutes to 20 hours. .
As the solvent, organic solvents such as toluene, hexane, and tetrahydrofuran (THF) are preferable.
When the compound represented by the general formula (III) and the compound represented by the general formula (IV) are reacted, a base such as triethylamine or pyridine may be added.

The composition of the present invention may contain a polymer of a plurality of different compounds (I). In that case, the copolymer which consists of several different compound (I) may be sufficient, and the mixture of a homopolymer may be sufficient. When the composition of the present invention includes a copolymer composed of a plurality of different compounds (I), a copolymer of a mixture of two or more compounds (I ′) selected from m = 8, 10, and 12 It is preferable that
The polymer compound obtained by polymerizing the compound (I) contained in the composition of the present invention may be a copolymer with a compound other than the compound (I). The compound used in that case is preferably a compound having a plurality of polymerizable carbon-carbon unsaturated bonds or SiH groups. Examples of preferred compounds include vinyl silanes, vinyl siloxanes, phenylacetylenes, [(HSiO _0.5 ) ₃ ] _{8 and the} like.
The composition of the present invention may be a solution in which a reaction product (polymerized product) of compound (I) is dissolved in an organic solvent, or may be a solid material containing the reaction product of compound (I).

The composition of the present invention is produced by dissolving compound (I) in a solvent, adding a polymerization initiator and reacting a carbon-carbon unsaturated bond.
The polymerization reaction may be any polymerization reaction, and examples thereof include radical polymerization, cationic polymerization, anionic polymerization, ring-opening polymerization, polycondensation, polyaddition, addition condensation, and transition metal catalyst polymerization.

The polymerization reaction of compound (I) is preferably performed in the presence of a nonmetallic polymerization initiator. For example, polymerization can be carried out in the presence of a polymerization initiator that exhibits activity by generating free radicals such as carbon radicals and oxygen radicals by heating.
As the polymerization initiator, an organic peroxide or an organic azo compound is particularly preferably used.

  Examples of the organic peroxide include ketone peroxides such as perhexa H, peroxyketals such as perhexa TMH, hydroperoxides such as perbutyl H-69, park mill D, and perbutyl C, which are commercially available from Nippon Oil & Fats Co., Ltd. , Dialkyl peroxides such as perbutyl D, diacyl peroxides such as niper BW, peroxyesters such as perbutyl Z and perbutyl L, peroxydicarbonates such as perroyl TCP, diisobutyryl peroxide, cumylperoxyneodeca Noate, di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, di-sec-butyl peroxydicarbonate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, di (4 -T-Buchi Chlohexyl) peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxyneoheptanoate, t- Hexyl peroxypivalate, t-butyl peroxypivalate, di (3,5,5-trimethylhexanoyl) peroxide, dilauroyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2- Ethylhexanoate, disuccinic acid peroxide, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, t-hexylperoxy-2-ethylhexanoate, di (4-methyl Benzoyl) peroxide, t-butylperoxy-2-ethylhexanoe , Di (3-methylbenzoyl) peroxide, benzoyl (3-methylbenzoyl) peroxide, dibenzoyl peroxide, dibenzoyl peroxide, 1,1-di (t-butylperoxy) -2-methylcyclohexane, 1 , 1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-di (t-hexylperoxy) cyclohexane, 1,1-di (t-butylperoxy) cyclohexane, 2, , 2-di (4,4-di- (t-butylperoxy) cyclohexyl) propane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5 , -Trimethylhexanoate, t-butyl peroxylaurate, t-butyl peroxy Propyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-di-methyl-2,5-di (benzoylperoxy) hexane, t-butylperoxyacetate, 2,2-di- (t-butylperoxy) butane, t-butylperoxybenzoate, n-butyl-4,4-di-t-butylperoxyvalerate, di (2-t-butylperoxyisopropyl) ) Benzene, dicumyl peroxide, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylcumylperoxide, di-t-butylperoxide Oxide, p-methane hydroperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) Hexyne-3, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, 2,3-dimethyl-2,3-diphenylbutane, 2,4-dichlorobenzoyl peroxide, o-chlorobenzoyl peroxide, p-chlorobenzoyl peroxide, tris- (t-butylperoxy) triazine, 2,4,4-trimethylpentylperoxyneodecanoate, α -Cumylperoxyneodecanoate, t-amylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxytrimethyl Adipate, di-3-metho Cibutyl peroxydicarbonate, di-isopropyl peroxydicarbonate, t-butyl peroxyisopropyl carbonate, 1,6-bis (t-butylperoxycarbonyloxy) hexane, diethylene glycol bis (t-butyl peroxycarbonate), T-hexyl peroxyneodecanoate, Luperox 11 commercially available from Arkema Yoshitsugu, etc. are preferably used.

  As organic azo compounds, azonitrile compounds such as V-30, V-40, V-59, V-60, V-65, and V-70, which are commercially available from Wako Pure Chemical Industries, Ltd., VA-080, Azoamide compounds such as VA-085, VA-086, VF-096, VAm-110, and VAm-111, cyclic azoamidine compounds such as VA-044 and VA-061, and azoamidine compounds such as V-50 and VA-057 Azo ester compounds such as V-601, 2,2-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2-azobis (2,4-dimethylvaleronitrile), 2,2-azobis (2-methylpropionitrile), 2,2-azobis (2,4-dimethylbutyronitrile), 1,1-azobis (cyclohexane-1-carbonitrile), -[(1-cyano-1-methylethyl) azo] formamide, 2,2-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2, 2-azobis [2-methyl-N- (2-hydroxybutyl) propionamide], 2,2-azobis [N- (2-propenyl) -2-methylpropionamide], 2,2-azobis (N-butyl) -2-methylpropionamide), 2,2-azobis (N-cyclohexyl-2-methylpropioamide), 2,2-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2, 2-azobis [2- (2-imidazolin-2-yl) propane] disulfate dihydrate, 2,2-azobis {2- [1- (2-hydroxyethyl) 2-Imidazolin-2-yl] propane} dihydrochloride, 2,2-azobis [2- [2-imidazolin-2-yl] propane], 2,2-azobis (1-imino-1-pyrrolidino-2-methylpropane) ) Dihydrochloride, 2,2-azobis (2-methylpropionamidine) dihydrochloride, 2,2-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] tetrahydrate, dimethyl-2,2- Azobis (2-methylpropionate), 4,4-azobis (4-cyanovaleric acid), 2,2-azobis (2,4,4-trimethylpentane) and the like are preferably used.

As the polymerization initiator, alkyl peroxyesters and dialkyl peroxides, azonitrile compounds and azoester compounds are particularly preferred.
The polymerization initiator of the present invention may be used alone or in combination of two or more.
The amount of the polymerization initiator used in the present invention is preferably 0.001 to 2 mol, more preferably 0.05 to 1 mol, particularly preferably 0.01 to 0.5 mol, per 1 mol of the monomer.
The addition method of the polymerization initiator of the present invention includes batch addition, divided addition, continuous addition, etc., but it can be increased in molecular weight with a small addition amount of polymerization initiator and is advantageous from the viewpoint of film strength. And continuous addition is preferred.

Any solvent can be used for the polymerization reaction as long as it can dissolve the compound (I) at a necessary concentration and does not adversely affect the properties of the film formed from the polymer obtained. Also good. In the following description, for example, an ester solvent is a solvent having an ester group in the molecule.
For example, alcohol solvents such as water, methanol, ethanol, propanol, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, acetophenone, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, pentyl acetate, acetic acid Hexyl, methyl propionate, ethyl propionate, propylene glycol monomethyl ether acetate, γ-butyrolactone, ester solvents such as methyl benzoate, ether solvents such as dibutyl ether, anisole, tetrahydrofuran, toluene, xylene, mesitylene, 1,2, 4,5-tetramethylbenzene, pentamethylbenzene, isopropylbenzene, 1,4-diisopropylbenzene, t-butylbenzene, 1,4-di-t-butylbenzene Aroma such as 1,3,5-triethylbenzene, 1,3,5-tri-t-butylbenzene, 4-t-butyl-orthoxylene, 1-methylnaphthalene, 1,3,5-triisopropylbenzene Group hydrocarbon solvents, amide solvents such as N-methylpyrrolidinone, dimethylacetamide, carbon tetrachloride, dichloromethane, chloroform, 1,2-dichloroethane, chlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene And halogen-based solvents such as hexane, heptane, octane and cyclohexane. Among these solvents, more preferred are ester solvents, among which methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, pentyl acetate, hexyl acetate, methyl propionate, ethyl propionate, propylene glycol monomethyl ether acetate , Γ-butyrolactone and methyl benzoate, particularly preferably ethyl acetate and butyl acetate.

These may be used alone or in admixture of two or more.
If the concentration of compound (I) at the time of polymerization is high, the reaction solution will gel and a soluble polymer cannot be obtained. Therefore, the concentration of compound (I) at the time of polymerization needs to be 15% by mass or less. When the same solvent is used, the lower the concentration, the larger the number average molecular weight, and a composition that is soluble in an organic solvent can be easily synthesized. In that sense, the concentration of compound (I) in the reaction solution is preferably 11% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less.
From the viewpoint of productivity during the reaction, the higher the concentration of the compound (I) during the polymerization, the more advantageous. In that sense, the concentration of compound (I) during polymerization is 0.1% by mass or more, more preferably 1% by mass or more.

Optimum conditions for the polymerization reaction in the present invention vary depending on the polymerization initiator, monomer, solvent type, concentration, etc., but preferably the internal temperature is 0 ° C. to 200 ° C., more preferably 40 ° C. to 170 ° C., particularly preferably 70. C. to 150.degree. C., preferably 1 to 50 hours, more preferably 2 to 20 hours, and particularly preferably 3 to 10 hours.
Moreover, in order to suppress the inactivation of the polymerization initiator by oxygen, it is preferable to make it react under inert gas atmosphere (for example, nitrogen, argon, etc.). The oxygen concentration during the reaction is preferably 100 ppm or less, more preferably 50 ppm or less, and particularly preferably 20 ppm or less.
A preferred range of the weight average molecular weight (Mw) of the polymer at the end of the polymerization reaction is 50,000 to 500,000. More preferably, it is 60,000 to 400,000, and particularly preferably 70,000 to 300,000.

In the polymer of the compound (I) contained in the composition of the present invention, the reaction product of the compound (I) is preferably 60% by mass or more, preferably 80% by mass or more, and 90% by mass. More preferably, it is more preferably 95% by mass or more.
The larger these contents in the polymer, the lower the dielectric constant film can be formed.
The remaining compound (I) can be quantified from a solid GPC chart, HPLC chart, NMR spectrum, UV spectrum, IR spectrum, and the like. For copolymers and adducts other than compound (I) contained in the polymer, it may be determined by the charge ratio, but after purifying the polymer as necessary, NMR spectrum, UV spectrum, IR spectrum, It can also be quantified by measuring the elemental composition and the like.

  The composition of the present invention is preferably soluble in an organic solvent. Here, being soluble in an organic solvent means that 5% by mass or more dissolves at 25 ° C. in a solvent selected from cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and γ-butyrolactone. However, it is preferable to dissolve 10% by mass or more, and more preferable to dissolve 20% by mass or more.

  The Mw of the polymer of the compound (I) contained in the composition of the present invention is preferably 50,000 to 500,000, more preferably 60,000 to 400,000, and most preferably 70,000 to 300,000. preferable.

The Mn of the polymer of the compound (I) contained in the composition of the present invention is preferably 15,000 to 200,000, preferably 20,000 to 150,000, and 25,000 to 120,000. Most preferably it is.
In addition, the GPC polystyrene conversion value in this application uses Waters2695 and Shodex GPC column KF-805L, column temperature is 40 degreeC, tetrahydrofuran is used as an elution solvent at the flow volume of 1 ml / min, and sample concentration is 0.5 mass%. 50 μl of terahydrofuran solution was injected, a monomer calibration curve was prepared using the integral value of the RI detector (Waters 2414), the monomer in the solid content was quantified, and standard polystyrene was used for Mn and Mw. It is a value calculated using the calibration curve prepared in the above.
A film having a lower dielectric constant can be formed as the average molecular weight is larger. However, when the average molecular weight is larger, an insoluble matter in an organic solvent is easily generated. When the average molecular weight is in the above range, both low dielectric constant, solubility in organic solvents, and filterability can be achieved.
The polymer of the compound (I) contained in the composition of the present invention preferably contains substantially no component having a molecular weight of 3 million or more, more preferably contains substantially no component of 2 million or more, Most preferably, it contains no more than 1 million components.

The dispersion degree (Mw / Mn) of the polymer of the compound (I) contained in the composition of the present invention calculated from the GPC chart is preferably 1 to 15, more preferably 1 to 10, and most preferably 1 to 5. . When Mw is the same, a film having a lower dielectric constant can be formed when the degree of dispersion is smaller.
The unreacted compound (I) contained in the composition of the present invention is 40% by mass or less, preferably 20% by mass or less, more preferably 10% by mass or less, and more preferably 5% by mass or less. More preferably, it is most preferable that it is 2 mass% or less.
In the polymer of the compound (I) contained in the composition of the present invention, it is preferable that 10 to 99 mol% of the vinyl group or ethynyl group of the compound (I) remain unreacted. 90 mol% is preferably left unreacted and most preferably 30 to 80 mol% is left unreacted.
Moreover, 0.1-40 mass% of polymerization initiators, additives or polymerization solvents may be bonded to the polymer of the compound (I) in the composition of the present invention. % By mass is preferable, 0.1 to 10% by mass is more preferable, and 0.1 to 5% by mass is most preferable.
About these, it can quantify from the NMR spectrum etc. of a composition.

As a method for producing the composition having the physical properties described above, when polymerizing the compound (I), a high dilution condition is used, a chain transfer agent is added, a reaction solvent is optimized, and a polymerization initiator is continuously added. Examples thereof include a method of continuously adding compound (I), adding a radical trapping agent, and using living polymerization.
Moreover, after polymerizing the compound of compound (I), it is also possible to use methods such as filtering insoluble matter, purifying using column chromatography, or purifying by reprecipitation.
Here, the reprecipitation treatment refers to adding a poor solvent (a solvent that does not substantially dissolve the composition of the present invention) to the reaction solution obtained by distilling off the reaction solvent as necessary, or adding a reaction solvent as necessary. By dropping the distilled reaction liquid into a poor solvent, the composition of the present invention is precipitated, and this is filtered.
As the poor solvent, alcohols (methanol, ethanol, isopropyl alcohol) hydrocarbons (hexane, heptane) and the like are preferable. As the poor solvent, it is preferable to use an equal mass to 200-fold mass of the composition of the present invention, and it is more preferable to use a 2-fold mass to 50-fold mass. By performing the reprecipitation treatment, a film having a lower dielectric constant can be formed.

When producing the polymer of compound (I), the reaction solution obtained by subjecting compound (I) to the polymerization reaction may be used as it is, but it is preferable to distill off the reaction solvent and concentrate it. Moreover, it is preferable to use after performing a reprecipitation process.
The concentration is preferably carried out by heating and / or reducing the pressure of the reaction solution using a rotary evaporator, a distillation apparatus or a reaction apparatus in which a polymerization reaction is performed. The temperature of the reaction solution at the time of concentration is generally 0 ° C to 180 ° C, preferably 10 ° C to 140 ° C, more preferably 20 ° C to 100 ° C, and most preferably 30 ° C to 60 ° C. The pressure at the time of concentration is generally 0.133 Pa to 100 kPa, preferably 1.33 Pa to 13.3 kPa, and more preferably 1.33 Pa to 1.33 kPa.
When concentrating the reaction solution, it is preferably concentrated until the solid content in the reaction solution becomes 10% by mass or more, more preferably concentrated until it becomes 30% by mass or more, and 50% by mass or more. It is most preferred to concentrate until

  In the composition of the present invention and its production process, a polymerization inhibitor may be added in order to suppress unnecessary polymerization. Examples of the polymerization inhibitor include 4-methoxyphenol and catechol.

The composition of the present invention contains a heat-resistant organic polymer compound having a carbon-carbon unsaturated bond that can react with the polymer of compound (I) during film formation, etc., separately from the polymer of compound (I). .
The heat-resistant organic polymer compound is a compound having a weight average molecular weight of 500 to 5 million containing carbon atoms.

  Examples of heat-resistant organic polymer compounds include organosiloxane, polyacrylate, polymethacrylate, aminopolyacrylamide, isobutylene maleic anhydride amide, AAS (acrylonitrile-acrylate-styrene copolymer), AES (acrylonitrile-ethylene-propylene-styrene copolymer). ), AS (acrylonitrile-styrene copolymer), ABS (acrylonitrile-butadiene-styrene copolymer), ACS (blend of acrylonitrile-styrene copolymer and chlorinated polyethylene), MBS (methyl methacrylate-butadiene-styrene copolymer), ethylene-vinyl chloride copolymer , Ethylene-vinyl acetate copolymer, ethylene vinyl acetate vinyl chloride graft copolymer, ethylene vinyl alcohol Polymer, chlorinated polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, carboxyvinyl polymer, ketone resin, fluorinated plastic, polytetrafluoroethylene, fluorinated ethylene polypropylene copolymer, PFA (tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer) , Polychlorotrifluoroethylene, ethylenetetrafluoroethylene copolymer, polyvinylidene fluoride, polyvinyl fluoride, polyacetal, polyamide, nylon, copolymerized polyamide, polyamideimide, polyarylate, polyetherimide, polyetheretherketone, polyethylene, polyethylene oxide , Polyethylene terephthalate, Polyvinylidene chloride, Polyvinylidene chloride latex, Polyvinyl chloride , Polycarbonate, polyglutamic acid ester, polyvinyl acetate, polystyrene, polysulfone, polyethersulfone, polyaminesulfone, polyparavinylphenol, polyparamethylstyrene, polyallylamine, polyvinyl alcohol, polyvinyl acetate, polyvinyl ether, polyvinyl butyral, Polyvinyl formal, polyphenylene ether, polyphenylene sulfide, polybutadiene, polybutylene terephthalate, polypropylene, polymethylpentene, polymethyl methacrylate, polyacetylene, epoxy resin, oligoester acrylate, xylene resin, guanamine resin, diallyl phthalate resin, vinyl ester resin, phenol resin , Unsaturated polyester resin, furan resin, polyimide, polyurethane Typical examples are cellulose, cellulose acetate, celluloid, cellulose fatty acid ester, cellulose aromatic carboxylic acid ester, cellulose derivative, polyoxazoline, polyvinylpyrrolidone, polyvinyl acetate, polyethylene glycol dimethyl ether, gelatin, polyarylene, polybenzoxazole, etc. As mentioned.

Among these, organic siloxane, polyimide, polybenzoxazole, polyarylene, and polyacetylene are preferable.
Polymer compounds that form the above organic polymer compounds by known reactions are also preferred examples of the organic polymer compounds of the present invention.
These organic polymer compounds have heat resistance. The term “heat resistance” as used herein means that the weight loss when held at 300 ° C. for 1 hour in nitrogen is 10% or less.
These organic polymer compounds and precursors thereof have a carbon-carbon unsaturated bond that can react with the polymer of compound (I) during film formation.
The carbon-carbon unsaturated bond contained in the organic polymer compound may be introduced after the polymer compound is synthesized, or may be introduced in advance into a low molecular compound used to form the organic polymer compound. However, it is preferably introduced in advance into the low molecular weight compound.
In that case, the organic polymer compound may be formed by the reaction of a functional group existing separately from the carbon-carbon unsaturated bond in the low molecular compound, or the carbon-carbon unsaturated bond contained in the low molecular compound may be formed. An organic polymer compound may be formed by reacting 1 part.
Examples of these polymers include siloxane polymers synthesized by hydrolyzing and condensing alkoxysilanes having vinyl or ethynyl groups as substituents, aromatic dicarboxylic acids having vinyl or ethynyl groups, and o-aminophenol derivatives. Examples include polybenzoxazole synthesized by performing a condensation reaction using benzene, polyarylene synthesized by a reaction of an aromatic ethynyl group and a cyclopentadienone group, polyacetylene synthesized by a reaction of ethynyl groups, and the like.

  What is the mixing ratio of the polymer of compound (I) contained in the composition of the present invention to the heat-resistant organic polymer compound and its precursor? The weight ratio is preferably 1:99 to 99: 1, more preferably 5:95 to 95: 5, and most preferably 10:90 to 90:10.

  In the present invention, the polymer of compound (I) and the heat-resistant organic polymer compound are preferably used after being dissolved in a suitable solvent and coated on a support. Solvents that can be used include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, methyl isobutyl ketone, γ-butyrolactone, methyl ethyl ketone, methanol, ethanol, dimethylimidazolidinone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene Glycol dimethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), tetraethylene glycol dimethyl ether, triethylene glycol monobutyl ether, triethylene glycol monomethyl ether, Isopropanol, ethyl Carbonate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, diisopropylbenzene, toluene, xylene, mesitylene and the like are preferable, and these solvents are used alone or in combination.

  Among these, preferable solvents include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, 2-heptanone, cyclohexanone, γ-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl. Ether, propylene glycol monoethyl ether, ethylene carbonate, butyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, N-methylpyrrolidone, N, N-dimethylformamide, tetrahydrofuran, methyl isobutyl ketone, xylene, Mention may be made of mesitylene and diisopropylbenzene.

  A solution obtained by dissolving the composition of the present invention in a suitable solvent is also included in the scope of the composition of the present invention. The total solid content concentration in the solution of the composition of the present invention is preferably 1 to 30% by mass, and is appropriately adjusted according to the purpose of use. When the total solid content concentration of the composition is 1 to 30% by mass, the film thickness of the coating film is in an appropriate range, and the storage stability of the coating solution is also more excellent.

The composition of the present invention may contain a polymerization initiator, but it is preferable that no polymerization initiator is contained because the storage stability of the composition is good.
However, when it is necessary to harden the composition of this invention at low temperature, it is preferable to contain the polymerization initiator. Examples of the polymerization initiator in that case include the same ones as described above. For this purpose, initiators and sensitizers that cause polymerization by radiation can also be used.

  The composition of the present invention preferably has a sufficiently low metal content as an impurity. The metal concentration of the composition can be measured with high sensitivity by the ICP-MS method, and the metal content other than the transition metal in that case is preferably 30 ppm or less, more preferably 3 ppm or less, and particularly preferably 300 ppb or less. In addition, the transition metal has a high catalytic ability to promote oxidation, and from the viewpoint of increasing the dielectric constant of the film obtained in the present invention by an oxidation reaction in the prebaking and thermosetting processes, the content is preferably smaller. Preferably it is 10 ppm or less, More preferably, it is 1 ppm or less, Most preferably, it is 100 ppm or less.

The metal concentration of the composition can also be evaluated by performing total reflection X-ray fluorescence measurement on a film obtained using the composition of the present invention. When W line is used as the X-ray source, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pd can be observed as metal elements, each of which is 100 × 10 ¹⁰ cm ⁻² or less. Is more preferably 50 × 10 ¹⁰ cm ⁻² or less, and particularly preferably 10 × 10 ¹⁰ cm ⁻² or less. Moreover, Br which is halogen can also be observed, and the residual amount is preferably 10000 × 10 ¹⁰ cm ⁻² or less, more preferably 1000 × 10 ¹⁰ cm ⁻² or less, and particularly preferably 400 × 10 ¹⁰ cm ⁻² or less. is there. Further, although Cl can be observed as halogen, the remaining amount is preferably 100 × 10 ¹⁰ cm ⁻² or less, more preferably 50 × 10 ¹⁰ cm ⁻² or less from the viewpoint of damaging the CVD apparatus, the etching apparatus, and the like. Particularly preferably, it is 10 × 10 ¹⁰ cm ⁻² or less.

  Furthermore, the composition of the present invention includes a radical generator, a surfactant, and a silane coupling as long as the properties (heat resistance, dielectric constant, mechanical strength, coatability, adhesion, etc.) of the obtained insulating film are not impaired. You may add additives, such as an agent and an adhesive agent.

  Any surfactant may be used in the present invention, and examples thereof include nonionic surfactants, anionic surfactants, cationic surfactants, silicone surfactants, and fluorine-containing interfaces. Activators, polyalkylene oxide surfactants, and acrylic surfactants can be mentioned. The surfactant used in the present invention may be one type or two or more types. As the surfactant, silicone surfactants, nonionic surfactants, fluorine-containing surfactants, and acrylic surfactants are preferable, and silicone surfactants are particularly preferable.

  The addition amount of the surfactant used in the present invention is preferably 0.01% by mass or more and 1% by mass or less, and 0.1% by mass or more and 0.5% by mass or less with respect to the total amount of the film-forming coating solution. More preferably.

  In the present invention, the silicon-based surfactant is a surfactant containing at least one Si atom. The silicon-based surfactant used in the present invention may be any silicon-based surfactant, and preferably has a structure containing alkylene oxide and dimethylsiloxane. A structure including the following chemical formula is more preferable.

In the formula, R ¹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, x is an integer of 1 to 20, and m and n are each independently an integer of 2 to 100. A plurality of R ¹ may be the same or different.

  Examples of the silicone-based surfactant used in the present invention include BYK306, BYK307 (manufactured by Big Chemie), SH7PA, SH21PA, SH28PA, SH30PA (manufactured by Toray Dow Corning Silicone), Troysol S366 (manufactured by Troy Chemical). Can be mentioned.

  Any nonionic surfactant may be used as the nonionic surfactant used in the present invention. For example, polyoxyethylene alkyl ethers, polyoxyethylene aryl ethers, polyoxyethylene dialkyl esters, sorbitan fatty acid esters, fatty acid-modified polyoxyethylenes, polyoxyethylene-polyoxypropylene block copolymers, etc. Can do.

  As the fluorine-containing surfactant used in the present invention, any fluorine-containing surfactant may be used. For example, perfluorooctyl polyethylene oxide, perfluorodecyl polyethylene oxide, perfluorodecyl polyethylene oxide and the like can be mentioned.

  The acrylic surfactant used in the present invention may be any acrylic surfactant. For example, a (meth) acrylic acid type copolymer etc. are mentioned.

Any silane coupling agent may be used in the present invention. For example, 3-glycidyloxypropyltrimethoxysilane, 3-aminoglycidyloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- Glycidyloxypropylmethyldimethoxysilane, 1-methacryloxypropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N -(2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane Emissions, N- ethoxycarbonyl-3-aminopropyltrimethoxysilane, N- ethoxycarbonyl-3-aminopropyltriethoxysilane, N- triethoxysilylpropyl triethylene triamine, N- trimethinecyanine butoxy silyl propyl triethylene triamine, 10 -Trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3, 6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-amino Propyltriethoxysilane, - bis (oxyethylene) -3-aminopropyltrimethoxysilane, N- bis (oxyethylene) -3-aminopropyltriethoxysilane and the like. The silane coupling agent used in the present invention may be one type or two or more types.

Any adhesion promoter may be used in the present invention. For example, trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane , Γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, trimethoxyvinylsilane, γ-aminopropyltriethoxysilane, aluminum monoethylacetoacetate diisopropylate, vinyltris (2 -Methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3- Chloropropyltrimethoxy Sisilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, trimethylchlorosilane, dimethylvinylchlorosilane, methyldiphenylchlorosilane, chloromethyldimethylchlorosilane, trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane, dimethyl Vinylethoxysilane, diphenyldimethoxysilane, phenyltriethoxysilane, hexamethyldisilazane, N, N′-bis (trimethylsilyl) urea, dimethyltrimethylsilylamine, trimethylsilylimidazole, vinyltrichlorosilane, benzotriazole, benzimidazole, indazole, Imidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-merca DOO benzoxazole, urazole, thiouracil, mercaptoimidazole, mercaptopyrimidine, 1,1-dimethylurea, 1,3-dimethylurea, may be mentioned thiourea compounds. Functional silane coupling agents are preferred as adhesion promoters. The preferable use amount of the adhesion promoter is preferably 10 parts by mass or less, particularly 0.05 to 5 parts by mass with respect to 100 parts by mass of the total solid content.

In the composition of the present invention, a pore forming factor can be used within the range allowed by the mechanical strength of the film to make the film porous and to reduce the dielectric constant.
There are no particular limitations on the pore-forming factor of the additive that serves as the pore-forming agent, but non-metallic compounds are preferably used, solubility in the solvent used in the film-forming coating solution, and the polymer of the present invention. It is necessary to satisfy the compatibility of

  A polymer can also be used as the pore-forming agent. Examples of the polymer that can be used as the pore-forming agent include polyvinyl aromatic compounds (polystyrene, polyvinyl pyridine, halogenated polyvinyl aromatic compounds, etc.), polyacrylonitrile, polyalkylene oxide (polyethylene oxide, polypropylene oxide, etc.), polyethylene, poly Lactic acid, polysiloxane, polycaprolactone, polycaprolactam, polyurethane, polymethacrylate (such as polymethyl methacrylate) or polymethacrylic acid, polyacrylate (such as polymethyl acrylate) and polyacrylic acid, polydiene (such as polybutadiene and polyisoprene), polyvinyl chloride , Polyacetal, and amine-capped alkylene oxide, other polyphenylene oxide, poly (dimethyl) Siloxane), polytetrahydrofuran, poly cyclohexyl ethylene, polyethyl oxazoline, polyvinyl pyridine, may be a polycaprolactone.

In particular, polystyrene can be suitably used as a pore forming agent. Examples of polystyrene include anionic polymerized polystyrene, syndiotactic polystyrene, unsubstituted and substituted polystyrene (for example, poly (α-methylstyrene)), and unsubstituted polystyrene is preferred.
Further, a thermoplastic polymer can also be used as the pore forming agent. Examples of thermoplastic pore forming polymers include polyacrylate, polymethacrylate, polybutadiene, polyisoprene, polyphenylene oxide, polypropylene oxide, polyethylene oxide, poly (dimethylsiloxane), polytetrahydrofuran, polyethylene, polycyclohexylethylene, polyethyloxazoline. , Polycaprolactone, polylactic acid, polyvinyl pyridine and the like.

Moreover, the boiling point or decomposition temperature of the pore-forming agent is preferably 100 to 500 ° C, more preferably 200 to 450 ° C, and particularly preferably 250 to 400 ° C. As molecular weight, it is preferable that it is 200-50000, More preferably, it is 300-10000, Most preferably, it is 400-5000.
The amount of the pore-forming agent added is preferably 0.5 to 75%, more preferably 0.5 to 30%, and particularly preferably 1% to 20% by mass% with respect to the polymer forming the film. .
The polymer may contain a decomposable group as a pore-forming factor, and the decomposition temperature is preferably 100 to 500 ° C, more preferably 200 to 450 ° C, and particularly preferably 250 to 400 ° C. Good to have. The content of the decomposable group is 0.5 to 75%, more preferably 0.5 to 30%, and particularly preferably 1 to 20% in terms of mol% with respect to the polymer forming the film.

  The film-forming composition of the present invention is preferably used for film formation after removing insolubles, gel components and the like by filter filtration. The pore size of the filter used at that time is preferably 0.001 to 0.2 μm, more preferably 0.005 to 0.05 μm, and most preferably 0.005 to 0.03 μm. The material of the filter is preferably PTFE, polyethylene, or nylon, and more preferably polyethylene or nylon.

The film obtained by using the film forming composition of the present invention can be obtained by any method such as spin coating method, roller coating method, dip coating method, scanning method, spray method, bar coating method. After applying to a substrate such as a silicon wafer, a SiO ₂ wafer, a SiN wafer, glass, or a plastic film, the solvent can be removed by heat treatment as necessary. As a method of applying to the substrate, a spin coating method or a scanning method is preferable. Particularly preferred is the spin coating method.
For spin coating, commercially available equipment can be used. For example, the clean truck series (manufactured by Tokyo Electron), D-Spin series (manufactured by Dainippon Screen), SS series or CS series (manufactured by Tokyo Ohka Kogyo) can be preferably used. The spin coating conditions may be any rotational speed, but a rotational speed of about 1300 rpm is preferable for a 300 mm silicon substrate from the viewpoint of in-plane uniformity of the film. In addition, the method for discharging the composition solution may be either dynamic discharge for discharging the composition solution onto a rotating substrate or static discharge for discharging the composition solution onto a stationary substrate. From the viewpoint of performance, dynamic ejection is preferable. In addition, from the viewpoint of suppressing the consumption of the composition, it is also possible to use a method in which only the main solvent of the composition is preliminarily discharged onto the substrate to form a liquid film, and then the composition is discharged from there. it can. The spin coating time is not particularly limited, but is preferably within 180 seconds from the viewpoint of throughput. Further, from the viewpoint of transporting the substrate, it is also preferable to perform processing (edge rinse, back rinse) so as not to leave the film at the edge portion of the substrate. The heat treatment method is not particularly limited, but generally used hot plate heating, heating method using a furnace, light irradiation heating using a xenon lamp by RTP (Rapid Thermal Processor), etc. are applied. Can do. A heating method using hot plate heating or furnace is preferable. As the hot plate, a commercially available device can be preferably used, and the clean track series (manufactured by Tokyo Electron), D-Spin series (manufactured by Dainippon Screen), SS series or CS series (manufactured by Tokyo Ohka Kogyo Co., Ltd.) can be preferably used. As the furnace, α series (manufactured by Tokyo Electron) and the like can be preferably used.

  The polymer of the present invention is preferably hardened after being coated on a substrate. Hardened means that the composition on the substrate is cured and the film is given solvent resistance. As a method of hardening, it is particularly preferable to perform heat treatment (firing). For example, a polymerization reaction during post-heating of vinyl groups remaining in the polymer can be used. The conditions for this post-heat treatment are preferably 100 to 450 ° C., more preferably 200 to 420 ° C., particularly preferably 350 to 400 ° C., preferably 1 minute to 2 hours, more preferably 10 minutes to 1.5 ° C. Time, particularly preferably in the range of 30 minutes to 1 hour. The post-heating treatment may be performed in several times. Further, this post-heating is particularly preferably performed in a nitrogen atmosphere in order to prevent thermal oxidation by oxygen.

In the present invention, the film may be hardened by causing a polymerization reaction of a vinyl group or an ethynyl group remaining in the polymer by irradiating with a high energy ray instead of heat treatment. Examples of high energy rays include electron beams, ultraviolet rays, and X-rays, but are not particularly limited to these methods.
The energy when an electron beam is used as the high energy beam is preferably 0 to 50 keV, more preferably 0 to 30 keV, and particularly preferably 0 to 20 keV. The total dose of the electron beam is preferably 0 to 5 μC / cm ² , more preferably 0 to ² μC / cm ² , and particularly preferably 0 to 1 μC / cm ² . The substrate temperature at the time of irradiation with an electron beam is preferably 0 to 450 ° C, more preferably 0 to 400 ° C, and particularly preferably 0 to 350 ° C. The pressure is preferably 0 to 133 kPa, more preferably 0 to 60 kPa, and particularly preferably 0 to 20 kPa. From the viewpoint of preventing oxidation of the polymer of the present invention, the atmosphere around the substrate is preferably an inert atmosphere such as Ar, He, or nitrogen. Further, a gas such as oxygen, hydrocarbon, or ammonia may be added for the purpose of reaction with plasma, electromagnetic waves, or chemical species generated by interaction with an electron beam. The electron beam irradiation in the present invention may be performed a plurality of times. In this case, the electron beam irradiation conditions need not be the same each time, and may be performed under different conditions each time.
Ultraviolet rays may be used as the high energy rays. The irradiation wavelength region when using ultraviolet rays is preferably 190 to 400 nm, and the output is preferably 0.1 to 2000 mWcm ⁻² immediately above the substrate. The substrate temperature at the time of ultraviolet irradiation is preferably 250 to 450 ° C., more preferably 250 to 400 ° C., and particularly preferably 250 to 350 ° C. From the viewpoint of preventing oxidation of the polymer of the present invention, the atmosphere around the substrate is preferably an inert atmosphere such as Ar, He, or nitrogen. Further, the pressure at that time is preferably 0 to 133 kPa.

Heat treatment and high energy ray treatment irradiation at the same time. Or you may harden | cure by carrying out sequentially.
The film thickness when forming the insulating film is a dry film thickness of about 0.05 to 1.5 μm in thickness when applied once, and about 0.1 to 3 μm in thickness when applied twice. Can do.
Since the cage structure does not decompose during firing, it is preferable that groups (hydroxyl groups, silanol groups, etc.) that undergo nucleophilic attack on Si atoms are not substantially present during the production of the composition and the insulating film.

  More specifically, the composition of the present invention is applied onto a substrate (usually a substrate having a metal wiring) by, for example, a spin coating method, a pre-heat treatment is performed to dry the solvent, and then 300 ° C. to 430 ° C. An insulating film having a low dielectric constant can be formed by performing a final heat treatment (annealing) at a temperature of ℃ or less.

  When the film obtained by using the film forming composition of the present invention is used as an interlayer insulating film for a semiconductor, the wiring structure thereof may have a barrier layer for preventing metal migration on the wiring side surface. In addition to the cap layer and interlayer adhesion layer that prevent separation by CMP, there may be an etching stopper layer, etc. on the bottom surface of the upper surface of the wiring and interlayer insulating film. The seed material may be divided into a plurality of layers.

  The insulating film of the present invention may be used by forming a laminated structure with other Si-containing insulating films or organic films. It is preferable to use it laminated with a hydrocarbon film.

  The film obtained using the film forming composition of the present invention can be etched for copper wiring or other purposes. Etching may be either wet etching or dry etching, but dry etching is preferred. For dry etching, either ammonia-based plasma or fluorocarbon-based plasma can be used as appropriate. These plasmas can use not only Ar but also oxygen, or gases such as nitrogen, hydrogen, and helium. In addition, after the etching process, ashing can be performed for the purpose of removing the photoresist or the like used for the processing, and further, cleaning can be performed to remove a residue at the time of ashing.

  The film obtained by using the film forming composition of the present invention can be subjected to CMP (Chemical Mechanical Polishing) in order to planarize the copper plating portion after the copper wiring processing. As the CMP slurry (chemical solution), commercially available slurries (for example, manufactured by Fujimi, manufactured by Rodel Nitta, manufactured by JSR, manufactured by Hitachi Chemical, etc.) can be used as appropriate. Moreover, as a CMP apparatus, a commercially available apparatus (Applied Materials Co., Ltd., Ebara Seisakusho etc.) can be used suitably. Furthermore, it can be washed to remove the slurry residue after CMP.

  The film obtained using the film forming composition of the present invention can be used for various purposes. For example, it is suitable as an insulating film for semiconductor devices such as LSI, system LSI, DRAM, SDRAM, RDRAM, and D-RDRAM, and electronic parts such as multichip module multilayer wiring boards, interlayer insulating film for semiconductor, etching stopper film, surface protection In addition to films, buffer coat films, LSI passivation films, alpha ray blocking films, flexographic printing plate cover lay films, overcoat films, flexible copper clad cover coats, solder resist films, liquid crystal alignment films, etc. I can do it. It can also be used as a surface protective film, an antireflection film, or a retardation film for optical devices.

  By this method, an insulating film having a low dielectric constant, that is, an insulating film having a relative dielectric constant of 2.7 or less, preferably 2.5 or less can be obtained.

  The present invention will be described more specifically with reference to the following examples. However, the scope of the present invention is not limited to these examples.

[Synthesis Example 1]
1 g of exemplary compound (Id) was added to 55 g of butyl acetate, and the mixture was heated to reflux in a nitrogen stream. As a polymerization initiator, 8 μl of 2 μl of Lupelox 11 manufactured by Arkema Yoshitsugu was added every 2 hours, and the mixture was further heated to reflux for 4 hours. Next, the mixture was cooled to room temperature and concentrated under reduced pressure to a liquid weight of 1.5 g. After adding 20 ml of methanol and stirring for 1 hour, the solid matter was collected by filtration and dried to obtain 0.80 g of a solid content (A-1). . When the solid content was analyzed by GPC, Mw was 208,000 and Mn was 39,000. The unreacted exemplary compound (Id) in the solid was 1% by mass or less. The solid content did not substantially contain a component having a molecular weight of 2 million or more. As GPC, Waters 2695 and Shodex GPC column KF-805L are used, column temperature is 40 ° C., tetrahydrofuran is used as an elution solvent at a flow rate of 1 ml / min, and a terahydrohydrofuran solution having a sample concentration of 0.5 mass%. Was injected. A monomer calibration curve was created using the integrated value of the RI detector (Waters 2414), and the monomer in the solid content was quantified. Mn and Mw were calculated using a calibration curve prepared using standard polystyrene.
When a ¹ H-NMR spectrum of solid content was measured using deuterated chloroform as a measurement solvent, the proton peak derived from the alkyl group formed by polymerizing the vinyl group and the remaining proton peak derived from the vinyl group had an integration of 43:57. The ratio was observed and it was found that vinyl groups were polymerized. It is clear that (A-1) contains 60% by mass or more of the reaction product of the compound (I).

According to Example 5 of JP-T-2002-534546, equimolar 3,3 ′-(oxydi1,4-phenylene) bis (2,4,5-triphenylcyclopentadienone) and 1,3,3 A polyphenylene polymer (Polymer 1) synthesized from 5-tris (phenylethynyl) benzene was obtained. When this polymer was analyzed by GPC, it was Mw = 181,000. It was confirmed from H-NMR and IR spectra that polymer 1 contains an unreacted ethynyl group that can react with the solid content (A-1) during film formation.
0.2 g of A-1 was added to 20 g of a solution containing polymer 1 (including 1 g of solid content) to prepare a composition (B-1).

[Synthesis Example 2]
500 mg of tetravinylsilane was added to 11 ml of butyl acetate. While heating and refluxing in a nitrogen stream, 5 μl of Luplox 11 manufactured by Arkema Yoshitosha was added every hour for a total of 5 times, and the mixture was further heated to reflux for 1 hour. After cooling to room temperature, the mixture was concentrated under reduced pressure, 20 ml of methanol was added and stirred for 1 hour, and then the solid was collected by filtration and dried to obtain 200 mg of a solid (polymer 2). When the solid content was analyzed by GPC, Mw was 191,000. It was confirmed from H-NMR and IR spectra that polymer 2 contains an unreacted vinyl group that can react with the solid content (A-1) during film formation. 100 mg of (Polymer 2) and 100 mg of (A-1) were dissolved in 4 ml of cyclohexanone. A composition (B-2) was produced.

[Synthesis Example 3]
20 g of 1,3-diethynyladamantane and 100 ml of 1,3,5-triisopropylbenzene were placed in a flask and heated and stirred at an internal temperature of 200 ° C. for 30 hours in a nitrogen stream. After cooling to room temperature, insoluble matters in the reaction solution were removed by filtration. Isopropyl alcohol was added to the obtained filtrate, and the precipitated solid was filtered. Further, the obtained solid was suspended in isopropyl alcohol, stirred, and then filtered again to obtain 7 g of a yellow polymer (polymer 3). As a result of GPC measurement, the quality average molecular weight was 31,000. It was confirmed from H-NMR and IR spectra that polymer 3 contains an unreacted ethynyl group that can react with the solid content (A-1) during film formation. 200 mg of (Polymer 3) and 100 mg of (A-1) were dissolved in 6 ml of cyclohexanone to prepare a composition (B-3).

[Synthesis Example 4]
0.2 g of exemplary compound (d-1) was added to 20 g of solution containing polymer 1 (including 1 g of solid content) to prepare a comparative composition (B-4).

[Examples 1 to 3, Comparative Examples 1 to 4]
Teflon (registered trademark) filters having a pore size of 0.2 μm each of 5 mass% cyclohexanone solutions of coating solutions (B-1) to (B-4) and (Polymer 1) to (Polymer 3) prepared in the above synthesis example After filtration on a 4-inch silicon wafer by spin coating, the substrate is dried on a hot plate at 130 ° C. for 1 minute and then at 230 ° C. for 1 minute, and further at 400 ° C. for 30 minutes in a clean oven in a nitrogen atmosphere. Coating films (C-1) to (C-7) were prepared by heating for minutes.

  The dielectric constant was measured using a mercury probe manufactured by Four Dimensions Inc. (measurement temperature 25 ° C.). The evaluation results are shown in Table 1.

  From the results shown in Table 1, it can be seen that a film having a low dielectric constant can be formed by using the composition of the present invention.

Claims (3)

The cage-type silsesquioxane compound having two or more unsaturated groups as substituents is at least one selected from polymer compounds obtained by polymerizing the following compounds ( Id) and the following A) to C): A composition for forming an insulating film comprising a heat-resistant organic polymer compound having a carbon-carbon unsaturated bond and an organic solvent.

A) a polymer synthesized from 3,3 ′-(oxydi1,4-phenylene) bis (2,4,5-triphenylcyclopentadienone) and 1,3,5-tris (phenylethynyl) benzene,
B) a polymer synthesized from tetravinylsilane,
C) a polymer synthesized from 1,3-diethynyladamantane and 1,3,5-triisopropylbenzene, The polymer compound obtained by polymerizing the silsesquioxane compound (Id) has a polystyrene equivalent weight average molecular weight measured by GPC of 50,000 to 500,000, and a polystyrene equivalent number average molecular weight of 15,000 to 20%. The composition for forming an insulating film according to claim 1, wherein the composition is 10,000 . A method for producing an insulating film, comprising: applying a composition for forming an insulating film according to claim 1 or 2 onto a substrate, and then hardening the composition.