JP4460884B2 - Low dielectric material - Google Patents

Description

  The present invention relates to a low dielectric material and a manufacturing method thereof, and more particularly to a low dielectric material prepared using a borazine ring-containing compound. The low dielectric material of the present invention can be used as an interlayer insulating film for semiconductors.

  As the performance of information equipment increases, LSI design rules become finer year by year. In the manufacture of LSIs with fine design rules, the materials that make up LSIs must also have high performance and function on fine LSIs.

  For example, regarding materials used for interlayer insulating films in LSIs, a high dielectric constant causes signal delay. In a fine LSI, the influence of this signal delay is particularly great. For this reason, development of a new low dielectric material that can be used as an interlayer insulating film has been desired. Further, in order to be used as an interlayer insulating film, it is necessary not only to have a low dielectric constant but also to be excellent in characteristics such as moisture resistance, heat resistance and mechanical strength.

  As a response to such a demand, a compound having a borazine ring skeleton has been proposed (for example, see Patent Document 1). Since the compound having a borazine ring skeleton has a low molecular polarizability, the formed film has a low dielectric constant. In addition, the formed film is excellent in heat resistance.

In addition, a polymer composition composed of a compound having a borazine ring skeleton and an organosilicon compound has been proposed (see, for example, Patent Document 2). A film formed using a polymer composition comprising a compound having a borazine ring skeleton and an organosilicon compound has excellent moisture resistance and the like.
JP 2000-340689 A JP 2002-317049 A

  As described above, a compound having a borazine ring skeleton is very useful as a raw material for a low dielectric material used for an interlayer insulating film or the like. However, further improvements are required in order to increase the value as a low dielectric material.

  Therefore, an object of the present invention is to further improve the characteristics of a low dielectric material formed using a compound having a borazine ring skeleton.

（式中、Ｒ ^１ 、Ｒ ^３ およびＲ ^５ は、同一または異なっていてもよく、下記式（２）：

（式中、Ｒ ^７ はアルキル基である）
で表される官能基であり、Ｒ ^２ 、Ｒ ^４ およびＲ ^６ は、同一または異なっていてもよく、水素原子またはアルキル基であり、Ｒ ^２ 、Ｒ ^４ およびＲ ^６ の少なくとも１つが水素原子である）
で表される化合物、またはその重合体を含む組成物を、酸素濃度０．１体積％以下の雰囲気中で、２００〜６００℃で焼成して得られる低誘電材料である。 The present invention provides the following formula (1):

(Wherein R ¹ , R ³ and R ⁵ may be the same or different, and the following formula (2):

(Wherein R ⁷ is an alkyl group)
R ² , R ⁴ and R ^{6, which} may be the same or different, are a hydrogen atom or an alkyl group, and at least one of R ² , R ⁴ and R ⁶ is a hydrogen atom is there)
A compound represented by, or a composition comprising the polymer, an oxygen concentration of 0.1 vol% in the following atmosphere is a low dielectric material obtained by baking at 200 to 600 ° C..

  Since the low dielectric material of this invention is formed using the composition containing a borazine ring containing compound, its dielectric constant is low. Further, by controlling the oxygen concentration during firing, the dielectric constant of the formed dielectric material is further reduced. Furthermore, by controlling the temperature during firing, the moisture resistance and film-forming property of the formed dielectric material are improved.

  A low dielectric material having such characteristics is particularly useful as an interlayer insulating film in a semiconductor device, and the low dielectric material of the present invention can greatly contribute to the realization of high-speed ULSI.

  As described above, a compound having a borazine ring skeleton is excellent as a raw material for a low dielectric material. The present inventors diligently studied to further improve the characteristics of a low dielectric material formed using a compound having a borazine ring skeleton. As a result, the present inventors have found that the firing conditions for producing the low dielectric material have a great influence on the characteristics of the low dielectric material to be formed, and completed the present invention. Moreover, the preferable borazine ring containing compound was discovered as a low dielectric material. Hereinafter, embodiments of the present invention will be described in detail.

  The first of the present invention is a low dielectric material obtained by firing a composition containing a borazine ring-containing compound at 200 to 600 ° C. in an atmosphere having an oxygen concentration of 0.1% by volume or less.

  In the present application, the borazine ring-containing compound is a compound represented by the following formula:

The compound which has the borazine ring represented by these. As can be seen from the above formula, nitrogen (N) and boron (B) of the borazine ring each have one bond that does not form a borazine ring. There are no particular limitations on the elements or functional groups outside the ring that bind to the nitrogen and boron that form the borazine ring. Examples of the element and functional group bonded to nitrogen or boron forming the borazine ring include a hydrogen atom, a halogen atom, an alkyl group, an amino group, and a borazinyl group.

  The borazine ring-containing compound may be a compound having one borazine ring or a compound having two or more borazine rings. The borazine ring-containing compound may be a polymer. In this application, as long as it has a borazine ring irrespective of the form and molecular weight of a compound, it is included by the concept of a "borazine ring containing compound". When the production process of the low dielectric material includes a step of applying a composition containing a borazine ring-containing compound by spin coating, the borazine ring-containing compound is preferably a polymer. Since the viscosity of the solution containing the polymer is high, it is convenient for application using spin coating.

  The polymer as the borazine ring-containing compound can be formed using a compound having a borazine ring skeleton as a monomer. A polymerization method and a polymerization form are not particularly limited. The polymerization method is selected depending on the functional group bonded to the borazine ring. For example, when an amino group is bonded, a polymer can be synthesized by condensation polymerization as shown in Examples. When a vinyl group or a functional group containing a vinyl group is bonded to the borazine ring, for example, a polymer can be formed by radical polymerization using a polymerization initiator. The polymer may be a homopolymer or a copolymer composed of two or more monomer units. The form of the copolymer may be any of a random copolymer, a block copolymer, a graft copolymer, and the like. If a monomer having three or more functional groups capable of forming a bond with another monomer is used, it is possible to obtain a polymer in which the monomers are bonded in a network.

  Preferably, the borazine ring-containing compound of the present invention has the following formula (1):

Or a polymer thereof.

R ¹ , R ³ and R ⁵ bonded to boron (B) constituting the borazine ring are a hydrogen atom, an alkyl group which may be substituted, or the following formula (2):

Is a functional group represented by R ¹ , R ³ and R ⁵ may be the same or different. In the formula (2), R ⁷ is an alkyl group.

The alkyl group that can be included as R ¹ , R ³ , R ⁵ and R ⁷ can be a linear, branched or cyclic alkyl group. Specific examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, 1-methyl-ethyl group, sec-butyl group, A tert-butyl group, a neopentyl group, a cyclohexyl group, etc. are mentioned. However, alkyl groups that can be included as R ¹ , R ³ , R ⁵ and R ⁷ are not limited thereto.

In the alkyl group that can be included as R ¹ , R ³ , R ^5, and R ⁷ , the hydrogen atom may be substituted with another functional group without departing from the effects of the present invention. Functional groups include amino groups, isocyanate groups, vinyl groups, ethynyl groups, and the like.

When it has a functional group represented by Formula (2), it is suitable for polycondensation of the borazine ring-containing compound represented by Formula (1). In that case, the borazine ring-containing compound used as a monomer preferably contains two or more functional groups of the formula (2). In order to obtain a network polymer, it is preferable to use a borazine ring-containing compound in which all of R ¹ , R ³ and R ⁵ are functional groups represented by the formula (2). Even in the case of synthesizing a network-like polymer, R ¹ , R ³ and R ⁵ must be functional groups represented by the formula (2) for all borazine ring-containing compounds used as monomers. There is no. When a film is formed using spin coating or the like, it is necessary to uniformly dissolve in an appropriate solvent. If the network-like polymer is three-dimensionally cross-linked at a high density, the uniformity of the solvent and the solubility of the polymer in the solvent may be reduced. For this reason, according to the solvent to be used and the borazine ring containing compound to be used, it is good to control the degree which is a network form.

  When using a composition containing a borazine ring-containing compound polymerized in a network, compared to using a composition consisting only of an unpolymerized borazine ring-containing compound, when forming a coating film using spin coating Improved workability. Such an effect is very large from the viewpoints of cost and productivity in industrial mass production of the present invention.

R ² , R ⁴ and R ⁶ bonded to nitrogen (N) constituting the borazine ring are a hydrogen atom or an alkyl group. R ² , R ⁴ and R ⁶ may be the same or different. The alkyl groups that can be included as R ² , R ^4, and R ⁶ are the same as those described in the above description as the alkyl groups that can be included as R ¹ , R ³ , R ^5, and R ^7. To do.

Moreover, at least 1 of R < ¹ > -R < ⁶ > in Formula (1) contains a hydrogen atom. When R ^{1 to} R ⁶ are not hydrogen atoms, polycondensation does not proceed, and a low dielectric material having sufficient mechanical strength and moisture resistance may not be formed.

  By calcining a composition containing a borazine ring-containing compound represented by the above formula (1) or a polymer thereof under the oxygen concentration and temperature conditions defined in the present invention, the dielectric constant and moisture resistance of the low dielectric material obtained are obtained. Sex can be significantly improved.

  Specific examples of the borazine ring-containing compound represented by the formula (1) include unsubstituted borazine; B, B ′, B ″ -tris (propylamino) borazine, B, B ′, B ″ -tris (hexylamino) ) Alkylaminoborazines such as borazine, B, B ′, B ″ -tris (methylamino) borazine, B, B ′, B ″ -tris (propylamino) -N, N′N ″ -trimethylborazine; mono- Examples include alkyl borazines such as B-methyl borazine, di-B-methyl borazine, mono-N-ethyl borazine, di-N-methyl borazine, tri-N-propyl borazine, mono-N-di-B-methyl borazine. It is done.

  The composition containing a borazine ring-containing compound may contain other components as long as it does not affect the effects of the present invention. For example, a polysiloxane polymer described in Patent Document 2 may be included. An appropriate amount of an inorganic or organic additive such as a curing catalyst, a wettability improver, a plasticizer, an antifoaming agent or a thickener may be included.

  The solvent for dissolving or dispersing the borazine ring-containing compound is not particularly limited. There is no particular limitation as long as it can dissolve the borazine ring-containing compound and other components added as necessary. For example, alcohols such as ethylene glycol and ethylene glycol monomethyl ether; aromatic hydrocarbons such as toluene, benzene, and xylene; hydrocarbons such as hexane, heptane, and octane; tetrahydrofuran, diglyme, and tetraglyme are used as solvents. Can be. These may be used alone or in combination of two or more. In the case of film formation using spin coating, diglyme is preferred. When diglyme or a derivative thereof is used as a solvent, the uniformity of the produced film is improved. Moreover, the cloudiness of the film is prevented. The amount of the solvent used for producing the boron-containing polymer composition of the present invention is not particularly limited, and may be determined according to the means for producing the low dielectric material. For example, when a film is formed by spin coating, the solvent and the amount of the solvent may be determined so that the viscosity is suitable for spin coating.

  The borazine ring-containing compound can be produced with appropriate consideration of known techniques. Therefore, in the present invention, the method for producing the borazine ring-containing compound is not particularly limited. For example, “Yoshiharu Kimura, Textiles and Industries, Vol. 52, No. 8, 341, 1996”, “Paine & Sneddon, Recent Developments in Borazine-Based Polymers,” Inorganic and Organic Polymers 35 ”. Reference can be made to known techniques described in 1994 and the like.

  The composition containing the borazine ring-containing compound is supplied to a desired site and solidified by drying. For example, in order to form a semiconductor interlayer insulating film, it may be applied onto a substrate by spin coating and dried. If a coating with the desired thickness cannot be obtained by a single coating and drying, the coating and drying may be repeated until the desired thickness is obtained. Film formation conditions such as the spin coater rotation speed, drying temperature, and drying time are not particularly limited.

  Application to the substrate may use a technique other than spin coating. For example, spray coating, dip coating, etc. can be used. Further, when a low dielectric substrate that is a bulk body is manufactured, a composition containing a borazine ring-containing compound is poured into a mold and molded, and the obtained molded body is fired.

  Thereafter, the dried film is fired in an atmosphere having an oxygen concentration of 0.1 vol% or less, preferably 0.0000001 vol% or less (0.1 vol ppm or less). When the oxygen concentration in the atmosphere is high, the dielectric constant of the obtained low dielectric material tends to increase. The lower the oxygen concentration in the atmosphere, the better, and the lower limit is not particularly limited.

  The oxygen concentration here refers to the oxygen concentration in the atmosphere inside the baking apparatus in which the coating is disposed. Specifically, the oxygen concentration can be determined by measurement using a zirconia oximeter.

  The baking temperature of the dried film is controlled to 200 to 600 ° C, preferably 300 to 500 ° C. If the firing temperature is too low, the moisture resistance of the resulting low dielectric material tends to decrease. On the other hand, if the firing temperature is too high, defects such as cracks may occur on the surface of the resulting low dielectric material.

  The firing temperature here means the highest temperature at the time of firing treatment. For example, the firing temperature is 400 ° C. when the firing temperature is gradually increased and maintained at 400 ° C. for 30 minutes and then cooled. The firing temperature can be measured using a thermocouple.

  The firing time of the dried film is not particularly limited. What is necessary is just to determine suitably considering characteristics, such as a dielectric constant and moisture resistance, about the low dielectric material obtained. Usually, the time from the start of temperature rise to the end of cooling is about 3 to 300 minutes.

  As described above, the low dielectric material of the present invention can be used as an interlayer insulating film for a semiconductor. That is, the second of the present invention is an interlayer insulating film for semiconductor made of the low dielectric material. A third aspect of the present invention is a semiconductor device having the semiconductor interlayer insulating film. Since the interlayer insulating film of the present invention is excellent in characteristics such as dielectric constant and moisture resistance, it is useful for various electronic components such as LSI elements and IC substrates. In particular, since the interlayer insulating film of the present invention has a low dielectric constant, it can greatly contribute to the realization of high-speed ULSI.

  The configuration of various electronic components such as LSI and IC is not particularly limited. Any semiconductor device may be used as long as the interlayer insulating film of the present invention can be formed, and the semiconductor device having the semiconductor interlayer insulating film of the present invention belongs to the technical scope of the present invention.

  According to a fourth aspect of the present invention, there is provided a method for producing a low dielectric material, comprising firing a composition containing a borazine ring-containing compound at 200 to 600 ° C. in an atmosphere having an oxygen concentration of 0.1% by volume or less. It is. The meanings of the borazine ring-containing compound, the oxygen concentration, and the like here are as described in the first aspect of the present invention, and thus the description thereof is omitted here. In the fourth aspect of the present invention, an application process, a drying process, and the like can be employed as necessary. Since these are also as described above, description thereof is omitted here.

  Next, the effects of the present invention will be described using examples. However, the technical scope of the present invention is not limited to the following examples.

[Synthesis Example 1]
B, B ′, B ″ -trichloroborazine (15 g) was dissolved in sufficiently dehydrated toluene (100 mL), and a mixed solution of n-propylamine (22 g), triethylamine (25 g) and toluene (100 mL) was added at room temperature. After dropwise addition, the mixture was stirred for 3 hours at 25 ° C. and further stirred for 3 hours at 60 ° C. After the resulting amine hydrochloride was removed by filtration, the solvent and unreacted amine were distilled off under reduced pressure. A yellow viscous liquid (22.5 g) of B, B ′, B ″ -tris (propylamino) borazine was obtained (see the following formula). The resulting compound was further stirred in xylene at 130 ° C. for 3 hours to advance the polycondensation reaction. After the reaction, the solvent was distilled off under reduced pressure to obtain a borazine ring-containing compound 1 which is a polymer having repeating units bonded in a network form (see the following formula).

[Synthesis Example 2]
B, B ′, B ″ -trichloroborazine (15 g) was dissolved in sufficiently dehydrated toluene (100 mL), and a mixed solution of n-hexylamine (37 g), triethylamine (25 g) and toluene (100 mL) was added at room temperature. After dropwise addition, the mixture was stirred for 3 hours at 25 ° C. and further stirred for 3 hours at 60 ° C. After the resulting amine hydrochloride was removed by filtration, the solvent and unreacted amine were distilled off under reduced pressure. As a result, a yellow viscous liquid (30 g) of B, B ′, B ″ -tris (hexylamino) borazine was obtained. The resulting compound was further stirred in xylene at 130 ° C. for 3 hours to advance the polycondensation reaction. After the reaction, the solvent was distilled off under reduced pressure to obtain a borazine ring-containing compound 2.

[Synthesis Example 3]
B, B ′, B ″ -trichloroborazine (15 g) was dissolved in sufficiently dehydrated toluene (100 mL) and added dropwise to a flask containing methylamine (16 g) maintained at about −70 ° C. over 1 hour. After completion of the dropwise addition, the mixture was stirred for 3 hours at 25 ° C. and further stirred for 3 hours at 60 ° C. After removing the resulting amine hydrochloride by filtration, the solvent and unreacted amine were distilled off under reduced pressure, and B and B A white viscous liquid (12 g) of ', B ″ -tris (methylamino) borazine was obtained. The resulting compound was further stirred in xylene at 130 ° C. for 3 hours to advance the polycondensation reaction. After distilling off the solvent under reduced pressure, a borazine ring-containing compound 3 was obtained.

[Synthesis Example 4]
B, B ′, B ″ -trichloro-N, N′N ″ -trimethylborazine (15 g) was dissolved in sufficiently dehydrated toluene (100 mL), and n-propylamine (14 g), triethylamine (23 g), toluene 100 mL was dissolved. Was added dropwise at room temperature over 1 hour. After completion of dropping, the mixture was stirred at 25 ° C. for 3 hours and at 60 ° C. for 3 hours. After the generated amine hydrochloride was removed by filtration, the solvent and unreacted amine were distilled off under reduced pressure, and yellow viscosity of B, B ′, B ″ -tris (propylamino) -N, N′N ″ -trimethylborazine was obtained. A liquid (17 g) was obtained. The resulting compound was further stirred in xylene at 130 ° C. for 3 hours to advance the polycondensation reaction. After distilling off the solvent under reduced pressure, a borazine ring-containing compound 4 was obtained.

[Example 1]
The borazine ring-containing compound 1 obtained in Synthesis Example 1 was dissolved in sufficiently dried xylene to obtain a solution having a borazine ring-containing compound concentration of 10% by mass. This solution was applied to a silicon substrate at 3000 rpm using a spin coater and dried at 120 ° C. for 3 minutes. By repeating this operation 8 times, a film having a thickness of 1 μm was obtained. When this film was baked at 350 ° C. for 30 minutes in an argon atmosphere having an oxygen concentration of 0.1 ppm or less, a transparent and crack-free film 1 was formed. A gold electrode was deposited on the coating 1, and the dielectric constant of the film was measured. In addition, the moisture resistance of the film was evaluated. The results are shown in Table 1.

  In addition, in the moisture resistance evaluation, the appearance change under the condition of 20 ° C. and 20% Rh was observed, ◎ when there was no change for 2 days or more, ○ changed within 1-2 days, ○ changed within 1 day Was marked with x.

[Example 2]
A film 2 was formed according to the procedure of Example 1 except that the borazine ring-containing compound 2 obtained in Synthesis Example 2 was used. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 2.

[Example 3]
A coating 3 was formed according to the procedure of Example 1 except that the borazine ring-containing compound 3 obtained in Synthesis Example 3 was used. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 3.

[Example 4]
A film 4 was formed according to the procedure of Example 1 except that the borazine ring-containing compound 4 obtained in Synthesis Example 4 was used. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 4.

[Example 5]
A film 5 was formed according to the procedure of Example 1 except that the firing temperature was 550 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the film 5.

[Example 6]
A film 6 was formed according to the procedure of Example 2 except that the firing temperature was 550 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the film 6.

[Example 7]
A film 7 was formed according to the procedure of Example 3 except that the firing temperature was 550 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the film 7.

[Example 8]
A film 8 was formed according to the procedure of Example 4 except that the firing temperature was 550 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 8.

[Example 9]
A film 9 was formed in accordance with the procedure of Example 1 except that the baking temperature was 200 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the film 9.

[Example 10]
A film 10 was formed according to the procedure of Example 2 except that the firing temperature was 200 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 10.

[Example 11]
A film 11 was formed according to the procedure of Example 3 except that the baking temperature was 200 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 11.

[Example 12]
A film 12 was formed according to the procedure of Example 4 except that the baking temperature was 200 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 12.

[Comparative Example 1]
A coating 13 was formed in accordance with the procedure of Example 1 except that firing was performed in air with an oxygen concentration of 20%. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 13.

[Comparative Example 2]
A coating 14 was formed in accordance with the procedure of Example 2 except that firing was performed in air with an oxygen concentration of 20%. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 14.

[Comparative Example 3]
A film 15 was formed in accordance with the procedure of Example 3 except that firing was performed in air with an oxygen concentration of 20%. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 15.

[Comparative Example 4]
A coating film 16 was formed according to the procedure of Example 4 except that firing was performed in air with an oxygen concentration of 20%. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 16.

[Comparative Example 5]
A coating film 17 was formed according to the procedure of Example 1 except that the firing temperature was 150 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the film 17.

[Comparative Example 6]
A film 18 was formed in accordance with the procedure of Example 2 except that the baking temperature was 150 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 18.

[Comparative Example 7]
A coating film 19 was formed according to the procedure of Example 3 except that the baking temperature was 150 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the film 19.

[Comparative Example 8]
A coating film 20 was formed according to the procedure of Example 4 except that the firing temperature was 150 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 20.

[Comparative Example 9]
A coating film 21 was formed according to the procedure of Example 1 except that the firing temperature was set to 700 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 21.

[Comparative Example 10]
A coating film 22 was formed according to the procedure of Example 2 except that the baking temperature was set to 700 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 22.

[Comparative Example 11]
A coating film 23 was formed according to the procedure of Example 3 except that the baking temperature was set to 700 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 23.

[Comparative Example 12]
A coating 24 was formed in accordance with the procedure of Example 4 except that the firing temperature was 700 ° C. Table 1 shows the measurement results of the dielectric constant and moisture resistance of the coating 24.

  As shown in Comparative Examples 1 to 4 (films 13 to 16), when the oxygen concentration in the firing atmosphere was high, the dielectric constant of the obtained low dielectric material was increased. As shown in Comparative Examples 5 to 8 (Coatings 17 to 20), when the firing temperature was low, the resulting low dielectric material had insufficient moisture resistance. The obtained low dielectric material did not have a function as a low dielectric material because the film was decomposed by moisture in the atmosphere. As shown in Comparative Examples 9 to 12 (Coatings 21 to 24), when the firing temperature was high, cracks occurred in the obtained low dielectric material. A part of the low dielectric material was peeled off from the substrate. On the other hand, the low dielectric material of the present invention has a low dielectric constant and excellent moisture resistance.

  Thus, the low dielectric material of the present invention has a low dielectric constant and also has high moisture resistance. The low dielectric material of the present invention is particularly useful as an interlayer insulating film in a semiconductor device, and can greatly contribute to the realization of high-speed ULSI.

Claims (4)

Following formula (1):

(Wherein R ¹ , R ³ and R ⁵ may be the same or different, and the following formula (2):

(Wherein R ⁷ is an alkyl group)
R ² , R ⁴ and R ^{6, which} may be the same or different, are a hydrogen atom or an alkyl group, and at least one of R ² , R ⁴ and R ⁶ is a hydrogen atom is there)
A low dielectric material obtained by firing a composition containing the compound or a polymer thereof at 200 to 600 ° C. in an atmosphere having an oxygen concentration of 0.1% by volume or less. An interlayer insulating film for a semiconductor comprising the low dielectric material according to claim 1 . The semiconductor device having a semiconductor interlayer insulating film according to claim 2. Following formula (1):

(Wherein R ¹ , R ³ and R ⁵ may be the same or different, and the following formula (2):

(Wherein R ⁷ is an alkyl group)
R ² , R ⁴ and R ^{6, which} may be the same or different, are a hydrogen atom or an alkyl group, and at least one of R ² , R ⁴ and R ⁶ is a hydrogen atom is there)
A method for producing a low dielectric material, comprising firing a compound represented by the formula: or a composition containing the polymer thereof at 200 to 600 ° C. in an atmosphere having an oxygen concentration of 0.1% by volume or less.