JP2003218105A - Resin composition for forming electrically insulative thin film, method for forming the electrically insulative thin film, and the electrically insulative thin film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for forming an electrically insulative thin film by which a porous and low-dielectric-constant electrically insulative thin film can be formed, a method to efficiently from the porous and low- dielectric-constant electrically insulative thin film on the surface of an electric device, and the porous and low-dielectric-constant electrically insulative thin film. <P>SOLUTION: This resin composition for forming an electrically insulative thin film comprises at least (A) an electrically insulative resin with high energy ray crosslinking property and thermal crosslinking property, (B) a high energy degradable resin, and (C) a solvent. This method is used to apply the composition onto the surface of an electronic device, allow the (C) element to be evaporated partially or entirely and form a film, give a high-energy ray thereto to crosslink the (A) element and decompose the (B) element, and to remove the decomposed substance by heating. Thus, an electrically insulative thin film is formed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for forming an electrically insulating thin film, a method for forming an electrically insulating thin film, and an electrically insulating thin film, and more particularly to a porous and electrically insulating thin film having a low dielectric constant. The present invention relates to a resin composition for forming an electrically insulating thin film, a method for efficiently forming a porous electrically insulating thin film having a low dielectric constant on the surface of an electronic device, and a porous electrically insulating thin film having a low dielectric constant.

[0002]

2. Description of the Related Art In recent years, with the miniaturization and high integration of electronic devices, it has been required to form an electric insulating layer having a low dielectric constant on the surface of the electronic device. In particular, next-generation design rules of 0.10 μm are required. In the following highly integrated circuits, it is required to form an electric insulating layer having a low dielectric constant of 2.5 or less on the surface of an electronic device.

As a method of forming an electrically insulating layer having a low dielectric constant on the surface of an electronic device, US Pat. No. 5,548,159 discloses a method of applying a hydrogen silsesquioxane resin solution to the surface of an electronic device and removing the solvent. A method of heating the resin to form a porous electrically insulating thin film has been proposed. Further, Japanese Patent Laid-Open No. 10-2796887 discloses that
Electrical insulation comprising an electrically insulating / curable organic resin, a solvent capable of dissolving the organic resin, and a solvent having a boiling point or vapor pressure curve different from that of the solvent or the solvent having a different affinity for the organic resin A resin composition for forming a conductive thin film has been proposed, and after applying the composition to the surface of an electronic device, at least a part of the solvent is evaporated, and then the resin is heated and cured, or the solvent is gasified after the curing. There is proposed a method of forming a porous electrically insulating thin film by forming a porous electrically insulating film. Further, in JP-A-10-283843, an electrically insulating / curable inorganic resin or organic resin, a solvent and heat or interaction with the resin in the temperature range of 0 to 800 ° C. generate volatilization or gas. To obtain, a resin composition for forming an electrically insulating thin film composed of a solvent-soluble substance has been proposed. After applying the composition to the surface of an electronic device, the solvent is removed, and then the resin is heated and cured, or A method of forming a porous electrically insulating thin film by gasifying and removing the solvent-soluble substance after curing has been proposed.

However, in these methods, the curing of the resin and the porosity of the thin film progress competitively due to heat, so that the pores are crushed in the process of forming the electrically insulating thin film, and the film shrinkage is large. Therefore, it is difficult to obtain an electrically insulating thin film having a sufficiently low dielectric constant with good reproducibility.

On the other hand, in Japanese Patent Laid-Open No. 11-135493, a thermosetting inorganic resin or organic resin having an electric insulating property and a solvent capable of dissolving the resin, and whether the solvent has a boiling point or a vapor pressure curve different from that of the solvent. Alternatively, a resin composition for forming an electrically insulating thin film composed of a solvent having a different affinity for the resin is applied to the surface of an electronic device, after evaporating at least a part of the solvent, irradiation with a high energy ray is performed to form the resin. A method of forming a porous electrically insulating thin film by removing the solvent during or after curing has been proposed.

However, even in this method, since the solvent for making the resin porous has a relatively low molecular weight, it is volatilized little by little before the resin is cured, and voids are formed in the process of forming the electrically insulating thin film. There is a problem that it is difficult to obtain an electrically insulating thin film having a sufficiently low dielectric constant with good reproducibility because the film shrinks and the film shrinks greatly.

[0007]

DISCLOSURE OF THE INVENTION The present inventors have achieved the present invention as a result of extensive studies to solve the above problems. That is, an object of the present invention is to provide a resin composition for forming an electrically insulating thin film which is capable of forming an electrically insulating thin film having a porous low dielectric constant, and an electrically insulating thin film having a porous low dielectric constant on an electronic device surface efficiently. It is to provide a method of forming and a porous, low dielectric constant electrically insulating thin film.

[0008]

The electrically insulating thin film-forming resin composition of the present invention comprises (A) a high energy ray crosslinkable or thermally crosslinkable electrically insulating resin and (B) a high energy ray decomposable resin. It is characterized by comprising at least a resin and a solvent (C).

The method for forming an electrically insulating thin film of the present invention is (A) a high energy ray crosslinkable or thermally crosslinkable electrically insulating resin, (B) a high energy ray decomposable resin, and (C). The resin composition for forming an electrically insulating thin film, which comprises at least a solvent, is applied to the surface of an electronic device, and the above (C) is used.
A film is formed by evaporating a part or all of the components, and (I) is irradiated with a high energy ray to produce the (A)
After crosslinking the components and decomposing the component (B),
The decomposition product of the component (B) is removed by heating, or the component (A) is crosslinked by the heating (II), and the component (B) is decomposed by irradiation with a high energy ray, and then the component is heated by the heating. Either remove the decomposition products of component (B),
Or (III) by irradiation with a high energy ray,
It is characterized in that the component is crosslinked, and then the component (B) is decomposed by irradiation with a high energy ray different from the high energy ray, and then the decomposed product of the component (B) is removed by heating. The electrically insulating thin film of the present invention is characterized by being formed by the above method.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION First, the electrically insulating thin film of the present invention is used.
The film forming resin composition will be described in detail. (A) component is high
Electrical insulation that crosslinks by irradiation of energy rays or heat
Resin, preferably by irradiation with high energy rays
It is a cross-linking resin. (A) component is a high energy wire rack
If it is a bridgeable resin, it has high energy to crosslink
Examples of gee rays include ultraviolet rays, electron beams and X-rays.
More preferably, it is an electron beam. As such (A) component
Can use a resin that can be used for negative resist.
Specifically, polyacryle such as polymethyl acrylate
Resin, polystyrene, hydrogen silsesquioxane resin,
Liglycidyl methacrylate, polyethylene, polyac
Rylamide, polymethyl vinyl ketone, chloromethylation
Polystyrene, polydiaryl orthophthalate, epo
Xylated polybutadiene, and mixtures of two or more thereof
The thing is illustrated. Crosslinked by irradiation with high energy rays,
Since silica with excellent electrical insulation can be formed,
Component (A) is hydrogen silsesquioxane resin
It is preferable. This hydrogen silsesquioxane resin is
formula: HSiO_3/2 With a trifunctional siloxane unit represented by
Uniform structure formula: [HSio_3/2]_n (In the formula, n is a positive integer.)
It's Sun. The molecular structure of this hydrogen silsesquioxane resin
Examples of the structure include a ladder type and a cage type. This la
The end of the Dar-type hydrogen silsesquioxane resin
As, a hydrogen atom, a hydroxyl group, a trimethylsiloxy group
It is illustrated. Such hydrogen silsesquioxane resin
Are disclosed, for example, in Japanese Examined Patent Publication No. 47-31838 and Japanese Unexamined Patent Publication No.
9-189126, or JP-A-60-424.
As described in Japanese Patent Publication No. 26, the trichlorosilane is hydrolyzed.
It is possible to produce by decomposing and polycondensing.

The component (B) is a resin which decomposes upon irradiation with high energy rays. Examples of the high energy ray for decomposing the component (B) include ultraviolet rays, electron beams and X-rays, and even if the high energy ray is different from the high energy ray for crosslinking the component (A). It is good, but high energy beams of the same kind are preferable, and electron beams are particularly preferable. As the component (B), a resin that can be used in a positive resist can be used, and specifically, polyalkyl methacrylate such as polymethyl methacrylate; poly α-methylstyrene, polymethyl isopropenyl ketone. , Polystyrene sulfone, polyisobutylene,
Examples include polymethacrylamide, polymethacrylonitrile, polycyanoacrylate, polyolefin sulfone, and mixtures of two or more thereof. It decomposes by irradiation with high-energy rays and tends to have a low molecular weight.
The component (B) is preferably polyisobutylene. The weight average molecular weight of this polyisobutylene is not limited, but it is preferably less than 1000, and further 100 to 1000 (however, 1000 is not included).
Is preferably within the range of 100 to 90
It is preferably in the range of 0, particularly 100 to 80
It is preferably in the range of 0.

In the composition, the content of the component (B) is not limited, but is 1 to 100 parts by weight of the component (A).
It is preferably in the range of 200 parts by weight. this is,
This is because if the content of the component (B) is less than the lower limit of the above range, the dielectric constant of the obtained electrically insulating thin film is less likely to decrease, while if it exceeds the upper limit of the above range, the resin composition obtained. This makes it difficult to form an electrically insulating thin film.

The component (C) is a solvent for dissolving the components (A) and (B), and is not particularly limited as long as it does not chemically change with these components. Examples of the component (C) include aromatic solvents such as toluene, xylene and mesitylene; aliphatic solvents such as hexane, heptane and octane; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; butyl acetate and isoamyl acetate. Aliphatic ester solvents such as; hexamethyldisiloxane, chain siloxanes such as 1,1,3,3-tetramethyldisiloxane; 1,1,3,3,5,5,7,7-octamethylcyclo Examples include cyclic siloxanes such as tetrasiloxane and 1,3,5,7-tetramethylcyclotetrasiloxane; silicone solvents such as silane such as tetramethylsilane and dimethyldiethylsilane.

In this composition, the content of the component (C) is not limited, but is 50 per 100 parts by weight of the component (A).
It is preferably at least parts by weight. This is because if the content of the component (C) is less than the lower limit of the above range, it becomes difficult to thinly apply the obtained resin composition for forming an electrically insulating thin film onto the surface of a substrate such as an electronic device.

Further, the composition may optionally contain a sensitizer, a catalyst, an acid / alkali generator and the like. Examples of the sensitizer include photo (ultraviolet) sensitizers such as amines; photocationic polymerization initiators such as iodonium salts and phosphonium salts; radical polymerization initiators such as azoisobutyronitrile. As the catalyst, when the component (A) is a silicone-based one, an addition reaction catalyst such as a platinum-based catalyst; a condensation reaction catalyst such as a tin-based catalyst or a titanium-based catalyst; an organic oxide or an oxime compound is exemplified. Further, when the component (A) is an epoxy type, an amine type catalyst, an acid anhydride type catalyst, a phenol type catalyst, an imidazole type catalyst and an onium salt are exemplified. The acid / alkali generator is a compound that generates acid / alkali by light,
Examples thereof include acid generators such as onium salts and sulfonates, and alkali (amine) generators such as oxime compounds. Although the contents of these components are not limited, the components (A) and (B)
It is preferably within the range of 1 to 1,000 parts by weight with respect to the total of 1 million parts by weight of the components.

Next, the method for forming the electrically insulating thin film of the present invention will be described in detail. In this method, first, the surface of the electronic device is coated with the above resin composition for forming an electrically insulating thin film. This resin composition for forming an electrically insulating thin film comprises (A) a high energy ray crosslinkable or thermally crosslinkable electrically insulating resin, (B) a high energy ray decomposable resin, and (C).
At least consisting of a solvent, these (A) component ~ (C)
The components, other optional components, and their contents are as described above. In the present method, examples of the method for applying the above-mentioned resin composition for forming an electrically insulating thin film on the surface of an electronic device include a spin coating method, a dip coating method, a spray coating method and a flow coating method.

Next, a part or the whole of the component (C) is evaporated to form a film containing at least the component (A) and the component (B). The method for evaporating the component (C) is not limited, and it is possible to evaporate a part or all of the component (C) when the resin composition for forming an electrically insulating thin film is applied to the surface of an electronic device. After that, it can be evaporated by leaving it at room temperature, heating, or further reducing the pressure.

Then, in the method (I), the coating film formed on the surface of the electronic device is irradiated with high energy rays to crosslink the component (A). As the high energy ray for cross-linking the component (A) with high energy ray, ultraviolet rays,
An electron beam and an X-ray are illustrated, and an electron beam is preferable. In this method, by irradiating with high energy rays (A)
The components are crosslinked and the component (B) is decomposed. The crosslinking of the component (A) and the decomposition of the component (B) may proceed simultaneously,
Further, the component (B) may be decomposed after the crosslinking of the component (A).

Finally, the decomposition product of the component (B) produced by irradiation with high energy rays is removed by heating. The heating temperature for removing the decomposition product of the component (B) is not limited, but it is preferably a temperature at which the decomposition product can be removed at a relatively low temperature in a short time, specifically, 400 ° C. or less. Is preferred. At the time of this heating, a heating furnace, a hot plate or the like may be used. Further, if necessary, the decomposition product may be removed under reduced pressure.

In the method (II), the component (A) is cross-linked by heating the film formed on the surface of the electronic device. The heating temperature for thermally crosslinking the component (A) is not limited, but is preferably a relatively low temperature at which the component (B) is not thermally decomposed and a temperature at which the component (A) can be crosslinked in a short time. . At the time of this heating, a heating furnace, a hot plate or the like may be used.

Next, the coating film obtained by crosslinking the component (A) is irradiated with high energy rays to decompose the component (B).
Examples of the high-energy rays include ultraviolet rays, electron rays, and X-rays, and electron rays are preferable. Then, the decomposed product of the component (B) generated by irradiation with high energy rays is removed by heating. The heating temperature for removing the decomposition product of the component (B) is not limited, but the decomposition product is kept at a relatively low temperature,
In addition, the temperature is preferably such that it can be removed in a short time, and specifically, it is preferably 400 ° C. or lower. At the time of this heating, a heating furnace, a hot plate or the like may be used. Further, if necessary, the decomposition product may be removed under reduced pressure.

In the method (III), the coating film formed on the surface of the electronic device is irradiated with a high energy ray to crosslink the component (A). As the high energy ray for cross-linking the component (A) with high energy ray, ultraviolet rays,
Examples of electron beams and X-rays are ultraviolet rays. Next, the film obtained by crosslinking the component (A) is added to the above (A).
The component (B) is decomposed by irradiating a high energy ray different from the high energy ray obtained by crosslinking the component.
Examples of high-energy rays for decomposing the component (B) with high-energy rays include ultraviolet rays, electron beams, and X-rays, and electron rays are preferable. Then, the decomposed product of the component (B) generated by irradiation with high energy rays is removed by heating.
The heating temperature for removing the decomposition product of the component (B) is not limited, but is preferably a temperature at which the decomposition product can be removed at a relatively low temperature in a short time, specifically, 40
It is preferably 0 ° C. or lower. In this heating,
A heating furnace, a hot plate or the like may be used. Further, if necessary, the decomposition product may be removed under reduced pressure.

Finally, the electrically insulating thin film of the present invention will be described in detail. The thin film is characterized by being formed by the above method. Since the electrically insulating thin film thus formed has a low relative dielectric constant (2.5 or less),
It is suitable as an interlayer insulating film for a highly integrated circuit, and is particularly suitable as an interlayer insulating film which is required to have a relative dielectric constant of 2.5 or less in the next generation.

[0024]

EXAMPLE A resin composition for forming an electrically insulating thin film of the present invention,
The method for forming the electrically insulating thin film and the electrically insulating thin film will be described in detail with reference to Examples. In addition, the physical-property value in an Example is a value in 25 degreeC. Further, the degree of crosslinking of the electrically insulating thin film and its dielectric constant were measured as follows. [Crosslinking degree of electrically insulating thin film] The degree of crosslinking of the electrically insulating thin film is determined by Fourier transform infrared absorption spectroscopy analysis.
It was judged by measuring the residual SiH% in the thin film. The residual SiH% in the electrically insulating thin film is 100% of the content of silicon atom-bonded hydrogen atoms in the film formed by removing the solvent by spin coating the resin composition for forming the electrically insulating thin film on the silicon wafer surface. The relative content of the silicon atom-bonded hydrogen atoms in the electrically insulating thin film is shown. [Dielectric Constant of Electrically Insulating Thin Film] An electrically insulating thin film is formed on the surface of a silicon wafer having a specific resistance value of 10 ⁻² Ω · cm, and the thin film is sandwiched between aluminum electrodes under the conditions of a temperature of 25 ° C. and a frequency of 1 MHz. It was measured by an impedance analyzer according to the method.

[Example 1] Average structural formula: [HSio_3/2]_n (N is a positive integer.) Hydrogen silsesquio
Xane resin 14.4% by weight, weight average molecular weight 470
Liisobutylene (Nissan Polyb manufactured by NOF CORPORATION)
20% by weight, and methyl isobutyl keto
65.6% by weight of electrically insulating thin film forming resin group
The product was prepared. Next, this composition is subjected to main rotation (3000
spin) spin coating on silicon wafer surface in 10 seconds
Evaporate the methyl isobutyl ketone while applying more
After forming the film, the electron beam (30
0 Mrad) to crosslink hydrogen silsesquioxane resin
At the same time, polyisobutylene was decomposed. Then,
Heat at 350 ° C for 1 hour in a quartz furnace in an atmosphere
By removing the decomposition products of sobutylene, film thickness = 12
600Å, residual SiH% = 67%, relative permittivity = 2.1
An electrically insulating thin film was formed. Film after spin coating
And infrared absorption spectra of electrically insulating thin films (250
0-3500 cm^-1 ), The electrical insulation
The thin film should have a methyl group of polyisobutylene or a methyl group.
2800-3000 cm belonging to the group^-1Absorption around
Since it has disappeared, this electrically insulating thin film is
It is a porous material containing no butylene and its decomposition products.
I was able to confirm that

Example 2 Average structural formula: Polysilane having a hydrogen silsesquioxane resin of 14.4% by weight and a weight average molecular weight of 640 represented by [HSiO _3/2 ] _n (n is a positive integer). An electrically insulating thin film-forming resin composition comprising 20% by weight of isobutylene (Nissan Polybutene 015N manufactured by NOF CORPORATION) and 65.6% by weight of methyl isobutyl ketone was prepared. Next, this composition is subjected to main rotation (300
(0 rpm) for 10 seconds, the surface of the silicon wafer was applied by spin coating, methyl isobutyl ketone was evaporated to form a film, and then the electron beam accelerated by 165 kV (3
(00 Mrad) to crosslink the hydrogen cis-sesquioxane resin and decompose polyisobutylene. Then
By heating at 350 ° C. for 1 hour in a nitrogen atmosphere quartz furnace to remove polyisobutylene decomposition products, film thickness = 1
4300Å, residual SiH% = 59%, relative permittivity = 2.2
Was formed into an electrically insulating thin film. Infrared absorption spectra of spin-coated films and electrically insulating thin films (25
00~3500cm ^-1) were compared, since the absorption near 2800 to 3000 cm ^-1 attributable has disappeared methyl group or methylene group, polyisobutylene in the electrically insulating thin film, polyisobutylene and It was confirmed that the product had no decomposition product and was porous.

Example 3 Average structural formula: A polysiloxane having a hydrogen silsesquioxane resin of 14.4% by weight and a weight average molecular weight of 330 represented by [HSiO _3/2 ] _n (n is a positive integer). Isobutylene (pearl oil E manufactured by NOF CORPORATION)
X) 20% by weight, and methyl isobutyl ketone 65.
An electrically insulating thin film-forming resin composition containing 6% by weight was prepared. Next, this composition is subjected to main rotation (3000 rpm) 1
Electron beam accelerated at 165 kV (300 Mrad) after evaporating methyl isobutyl ketone to form a film while applying it to the silicon wafer surface by spin coating for 0 seconds.
Was irradiated to crosslink the hydrogen silsesquioxane resin and decompose polyisobutylene. Then, by heating in a quartz furnace in a nitrogen atmosphere at 350 ° C. for 1 hour to remove decomposed products of polyisobutylene, film thickness = 9700Å,
An electrically insulating thin film having a residual SiH% of 65% and a relative dielectric constant of 1.9 was prepared. Infrared absorption spectrum of the film and the electrically insulating thin film after spin coating (2,500 to 350)
0 cm ⁻¹ ), this electrically insulating thin film shows that the absorption at around 2800 to 3000 cm ⁻¹ attributed to the methyl group or methylene group of polyisobutylene has disappeared. Was confirmed to be a porous material having no polyisobutylene and its decomposition products.

[Example 4] Average structural formula: [HSiO _3/2 ] _n (n is a positive integer.) Hydrogen silsesquioxane resin 12.4% by weight, weight average molecular weight 470 poly An electrically insulating thin film-forming resin composition comprising 10.7% by weight of isobutylene (Nissan Polybutene 06N manufactured by NOF CORPORATION) and 76.9% by weight of methyl isobutyl ketone was prepared. Next, this composition is subjected to main rotation (24
(00 rpm) for 10 seconds by spin coating on the surface of the silicon wafer to evaporate methyl isobutyl ketone to form a film, which is then irradiated with an electron beam (300 Mrad) accelerated at 165 kV to crosslink the hydrogen silsesquioxane resin. At the same time, polyisobutylene was differentiated. Then, by heating at 350 ° C. for 1 hour in a nitrogen atmosphere quartz furnace to remove the decomposed product of polyisobutylene, film thickness = 6900Å, residual SiH% = 43%, relative dielectric constant = 2.
An electrically insulating thin film of No. 3 was formed. Infrared absorption spectra of spin-coated films and electrically insulating thin films (2
500-3500 cm ^-1 ), the electrical insulation thin film shows that the absorption near 2800-3000 cm ^-1 attributed to the methyl group or methylene group of polyisobutylene disappears. It was confirmed that the conductive thin film was porous without polyisobutylene and its decomposed products.

[Embodiment 5] Average structural formula: [HSio_3/2]_n (N is a positive integer.) Hydrogen silsesquio
Xane resin 8.4% by weight, weight average molecular weight 470 poly
Isobutylene (Nissan Polybute manufactured by NOF CORPORATION)
06N) 11.5% by weight, and methyl isobutyl ketone
Ton 80.1% by weight of electrically insulating thin film forming resin
A composition was prepared. Next, this composition is subjected to main rotation (300
Spin coating on the surface of silicon wafer in 10 seconds
Evaporate the methyl isobutyl ketone while applying
After forming a film with the electron beam (3
(00Mrad) to irradiate hydrogen silsesquioxane resin.
As it bridged, polyisobutylene was decomposed. Then
Heat in a quartz furnace in a nitrogen atmosphere at 350 ° C for 1 hour to remove poly.
By removing the decomposition products of isobutylene, the film thickness = 6
000Å, residual SiH% = 45%, relative permittivity = 2.2
An electrically insulating thin film was formed. Film after spin coating
And infrared absorption spectra of electrically insulating thin films (250
0-3500 cm^-1 ), The electrical insulation
The thin film should have a methyl group of polyisobutylene or a methyl group.
2800-3000 cm belonging to the group^-1Absorption around
Since it has disappeared, this electrically insulating thin film is
It is a porous material containing no butylene and its decomposition products.
I was able to confirm that

Comparative Example 1 Average structural formula: [HSiO _3/2 ] _n (n is a positive integer) 17.1% by weight of hydrogen silsesquioxane resin, polybutadiene having a weight average molecular weight of 5100 (R-15H manufactured by Idemitsu Petrochemical Co., Ltd.
T) 5% by weight, and methyl isobutyl ketone 77.9
An electrically insulative thin film-forming resin composition consisting of wt% was prepared. Next, this composition is subjected to main rotation (3000 rpm) 10
After coating the surface of the silicon wafer by spin coating for 2 seconds to evaporate methyl isobutyl ketone to form a film, the hydrogen silsesquioxane resin was cross-linked by irradiation with an electron beam (300 Mrad) accelerated at 165 kV. Then, it was heated in a quartz furnace in a nitrogen atmosphere at 350 ° C. for 1 hour to form an electrically insulating thin film having a film thickness = 7200Å, residual SiH% = 40%, and a relative dielectric constant = 3.9. When the infrared absorption spectra (2500-3500 cm ^-1 ) of the film after spin coating and the electrically insulating thin film were compared, it was found that 2800-3 assigned to the methylene group of polybutadiene, etc.
Since there was no large change in absorption intensity near 000 cm ^-1 , it was confirmed that this electrically insulating thin film was a non-porous one having polybutadiene.

Comparative Example 2 Average structural formula: 8.5% by weight of hydrogen silsesquioxane resin represented by [HSiO _3/2 ] _n (n is a positive integer) and polybutadiene having a weight average molecular weight of 5100. (R-15H manufactured by Idemitsu Petrochemical Co., Ltd.
T) 11.5% by weight, and methyl isobutyl ketone 8
An electrically insulating thin film-forming resin composition containing 0.1% by weight was prepared. Next, this composition is subjected to main rotation (3000 rp).
m) Methyl isobutyl ketone was evaporated to form a film while applying it on the surface of a silicon wafer by spin coating for 10 seconds, and then an electron beam (300 kV) accelerated at 165 kV was applied.
Mrad) was irradiated to crosslink the hydrogen silsesquioxane resin. Then, heat in a quartz furnace in a nitrogen atmosphere at 350 ° C. for 1 hour to obtain a film thickness = 6500Å, residual SiH% = 38%,
An electrically insulating thin film having a relative dielectric constant of 4.0 was formed. When the infrared absorption spectra (2,500 to 3,500 cm ⁻¹ ) of the film after spin coating and the electrically insulating thin film were compared, it was found that 280 was assigned to the methylene group of polybutadiene or the like.
Since there was no significant change in the absorption intensity around 0 to 3000 cm ^-1 , it was confirmed that this electrically insulating thin film was a non-porous one having polybutadiene.

[0032]

The resin composition for forming an electrically insulating thin film of the present invention is characterized in that it can form an electrically insulating thin film having a porous and low dielectric constant. Further, the method of forming an electrically insulating thin film of the present invention is characterized in that a porous electrically insulating thin film having a low dielectric constant can be efficiently formed on the surface of an electronic device. Further, the electrically insulating thin film of the present invention is characterized by being porous and having a low dielectric constant.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/312 H01L 21/312 A 21/768 21/90 S (72) Inventor Takashi Nakamura Ichihara City, Chiba Prefecture Chikusaigan 2-2 Toray Dow Corning Silicone Co., Ltd. Research & Development Headquarters (72) Inventor Satoshi Mine 2-2 Chikusaigan, Ichihara City, Chiba Toray Dow Corning Silicone Co., Ltd. Research & Development Division F-term (reference) 4J002 BB17X CP04W GQ01 HA05 5F033 RR21 RR29 SS22 5F058 BA20 BC02 BC05 BF46 BH04 BH20 BJ02 5G305 AA07 AA11 AB10 BA09 CA26 CA47 CD12

Claims (7)

[Claims] 1. A resin composition for forming an electrically insulating thin film comprising at least (A) a high energy ray crosslinkable or thermally crosslinkable electrically insulating resin, (B) a high energy ray decomposable resin, and (C) a solvent. object. 2. The resin composition for forming an electrically insulating thin film according to claim 1, wherein the component (A) is a hydrogen silsesquioxane resin. 3. The resin composition for forming an electrically insulating thin film according to claim 1, wherein the component (B) is polyisobutylene. 4. A resin composition for forming an electrically insulating thin film, comprising at least (A) a high energy ray crosslinkable or thermally crosslinkable electrically insulating resin, (B) a high energy ray decomposable resin, and (C) a solvent. A substance is applied to the surface of an electronic device to form a film by evaporating a part or all of the component (C), and (I) the component (A) is crosslinked by irradiation with a high energy ray and the component (B) ) After decomposing the component, the decomposition product of the component (B) is removed by heating, or the component (A) is crosslinked by heating (II), and then the component (B) is irradiated by irradiation with high energy rays. After the decomposition, the decomposition product of the component (B) is removed by heating, or the component (A) is crosslinked by irradiation of (III) high energy rays, and then a high energy ray different from the high energy rays. After decomposing the component (B) by irradiation, forming method of the electrically insulating thin film and removing the decomposition product of the component (B) by heating. 5. The method for forming an electrically insulating thin film according to claim 4, wherein the component (A) is a hydrogen silsesquioxane resin. 6. The method for forming an electrically insulating thin film according to claim 4, wherein the component (B) is polyisobutylene. 7. An electrically insulating thin film formed by the method according to any one of claims 4 to 6.