JP4261297B2 - Method for modifying porous film, modified porous film and use thereof - Google Patents

Description

  The present invention relates to a method for modifying a porous film, a modified porous film, a semiconductor material using the modified porous film, and a semiconductor device. More specifically, the present invention relates to a modified porous film excellent in hydrophobicity and mechanical strength that can be used for optical functional materials, electronic functional materials, and the like, and a method for modifying a porous film for obtaining the same.

  Conventionally, zeolite and silica gel are known as porous materials mainly having Si—O bonds. Zeolite is a silica crystal with uniform pores, but no pore diameter exceeds 13 mm. Silica gel has pores in the meso region of 2 to 50 nm, but the pore distribution is not uniform. Therefore, the use of these materials has been limited.

  In contrast, a porous inorganic oxide having uniform mesopores is large and has uniform pores, and also has a large pore volume and surface area, so that the catalyst carrier, separation adsorbent, fuel cell, Expected to be used for sensors.

Many studies have been conducted on the production of oxides with such uniform mesopores. However, the use of organic compounds to control the structure of inorganic materials has led to the creation of new shapes and structures. The method has attracted attention. In particular, oxides with uniform mesopores synthesized by utilizing self-assembly of organic and inorganic compounds have higher pore volume and surface area than conventional oxides. It has been known. Here, the oxide with uniform mesopores means that the pores are regularly arranged in the oxide (periodic pore structure).
It means that the presence of a diffraction peak showing structural regularity is measured by a line diffraction method.

Examples of a method for producing an oxide having uniform mesopores utilizing self-organization of an organic compound and an inorganic compound include those disclosed in International Publication No. 91/11390. There, a method for producing by hydrothermal synthesis in a sealed heat-resistant container using silica gel and a surfactant is described. Bull. Chem. Soc. Jp. Journal, 1990, Vol. 63, p. 988, which describes a method of production by ion exchange between kanemite, a kind of layered silicate, and a surfactant.

  In recent years, oxides having uniform mesopores produced by such a method have been prepared in the form of films for use in optical functional materials, electronic functional materials, and the like.

For example, Nature magazine, 1996, 379, 703, J. Am. Am. Chem. So
c. 1999, 121, 7618, a method of forming a film by immersing a substrate in a sol-containing liquid comprising an alkoxysilane condensate and a surfactant and depositing porous silica on the surface of the substrate. Is described. Furthermore, Supramolecular SCie
nce, 1998, 5, 247, Adv. Mater. Magazine, 1998, 10 pages, 1280 pages, Nature magazine, 1997 pages, 389 pages, 364 pages, and Nature magazine, 1999 pages, 398 pages, 223 pages, organic compounds containing alkoxysilane condensates and surfactants. A method is described in which a solution dissolved in a solvent is applied to a substrate and then the organic solvent is evaporated to prepare a film on the substrate.

Among these, the former method of depositing porous silica on the surface of the substrate is disadvantageous in that it takes a long time to prepare the film and the yield is low because the porous silica is often precipitated as powder. There is. Therefore, the latter method of evaporating the organic solvent is superior for the preparation of the porous silica film.

  As a solvent used in the method of preparing a film on a substrate by evaporating the organic solvent, for example, a polyhydric alcohol glycol ether solvent, a glycol acetate ether solvent, an amide solvent, a ketone solvent, a carboxylic acid ester solvent, etc. No. 2000-38509 and a solvent such as an organic solvent having an amide bond and an organic solvent having an ester bond are described in WO 99/03926.

  On the other hand, recently, when such a porous silica film is used as an optical functional material, an electronic functional material, or the like, there is a need to achieve both low hygroscopicity and high mechanical strength of the film. For example, a porous silica film is promising as a film having a very low relative dielectric constant because the ratio of pores having a relative dielectric constant of 1 is high when used as an electronic functional material in a semiconductor interlayer insulating film. Due to the porous nature, the mechanical strength is significantly reduced. In addition, there is a drawback that water having a large dielectric constant is easily adsorbed to increase the relative dielectric constant.

  Therefore, as a method for preventing the adsorption of water, a method of introducing a hydrophobic functional group into the interlayer insulating film material has been proposed, but no method for improving the mechanical strength has been reported so far. For example, a method for preventing water adsorption by trimethylsilylating silanol groups in the pores has been proposed (see Patent Document 1 and Patent Document 2). However, it has been reported that this method cannot completely silylate silanol groups in the pores (see Non-Patent Document 1 and Non-Patent Document 2). Further, it has been reported that there is no effect on the mechanical strength (see Non-Patent Document 3).

  Moreover, the manufacturing method of the porous silica film by the coating liquid prepared using the co-condensate (cogelled product) of methyl trialkoxysilane and tetraalkoxysilane is proposed (refer patent document 3). This method improves the hydrophobicity of the resulting porous silica film by using a coating solution in which the proportion of methyltrialkoxysilane, which is a hydrophobic component, is increased. However, when the proportion of methyltrialkoxysilane used increases, the proportion of three-dimensional bonds of Si—O—Si bonds that form the skeleton of the porous silica film decreases, and the mechanical strength significantly decreases. Therefore, it is difficult to achieve both hydrophobicity and mechanical strength.

  In addition, a method for producing a hydrophobic mesoporous silica powder by partially hydrolyzing each of dimethylalkoxysilane and tetraalkoxysilane has been reported (see Non-Patent Document 4). The powder obtained by this method has a regular pore structure and excellent hydrophobicity even when a relatively large amount of dialkylalkoxysilane is introduced. However, since this production method requires several days for production, it is poor in practicality. Further, since the obtained product is a powder, it is difficult to use it for an optical functional material, an electronic functional material or the like.

  Moreover, it has been reported that the powder obtained by carrying out thin film coating of the tetramethyltetracyclosiloxane which is a cyclic siloxane compound on the powder surface shows hydrophobicity (refer nonpatent literature 5). However, since it is also a powder in this case, it is difficult to use it as an optical functional material, an electronic functional material, or the like.

In addition, a method of forming a film with a low-molecular silane compound vapor on the surface of a porous ceramic in the presence of a platinum catalyst to make it hydrophobic has been reported (Patent Document 4). However, in this method, the presence of a metal serving as a catalyst is indispensable for forming a film, so that the metal is present in the film, so that the dielectric constant increases when used as an electronic functional material. It adversely affects the electrical characteristics such as, and is not preferable.

  On the other hand, a method for forming a cyclic siloxane compound on a substrate by a plasma CVD method has been reported (see Patent Documents 5 to 8). In this method, a cyclic siloxane compound is decomposed by plasma and deposited on a substrate to form a film. Therefore, the obtained film has a very low porosity and a low relative dielectric constant. For example, a low relative dielectric constant required for use in a semiconductor interlayer insulating film cannot be expected. In addition, a very expensive device for generating plasma is required, which is not economically preferable.

As a report for improving the film strength, there is a method using an excimer beam (EB) cure (see Non-Patent Document 6). In this method, a porous film is placed on a single wafer heating stage installed in a vacuum chamber, and EB curing is performed in an argon atmosphere at 350 ° C. and 10 Torr (1333 Pa ), and the mechanical strength is improved by 1.5 times. To do. However, this process has the disadvantage that an expensive apparatus is required and the film thickness is reduced by the process. Such a change in film thickness is not preferable when used as an optical functional material or an electronic functional material.

  As described above, the technique for producing a porous film that satisfies both hydrophobicity and membrane strength is still insufficient.

On the other hand, such a porous film is also used as a semiconductor material such as an interlayer insulating film or an inter-wiring insulating film that electrically insulates between copper wirings. However, since copper has the property of diffusing into the silica film, a barrier film made of titanium nitride (TiN) or tantalum nitride (TaN) is formed between the copper wiring and the silica film to prevent copper diffusion. There is a need to. This barrier film is formed on the surface of the porous film by a vapor deposition method (CVD; Chemical Vapor Deposition). If the film is porous, the reaction gas diffuses into the pores. For this reason, there is a problem that the porosity of the porous silica film decreases and the dielectric constant increases.
International Publication No. 00/39028 Pamphlet US Pat. No. 6,208,014 JP 2001-049174 A US Pat. No. 5,939,141 JP-A-5-202478 US Published Application No. 2002098714 International Publication No. 02/043119 Pamphlet US Pat. No. 6,348,725 J. et al. Phys. Chem. Journal, B1997, 101, 6525 J. et al. Colloid Interface Sci. Magazine, 1997, 188, 409 J. et al. Electrochem. Soc. , Magazine, 2003, 150, 6, F123 Chem. Commun. Magazine, 2000, p. 1487 Journal of Surface Science, 2001, 22, vol.9 IITC Proceedings 2003, 106

The present invention solves the problems associated with the prior art as described above, and is a modified porous film excellent in hydrophobicity and mechanical strength that can be used for optical functional materials and electronic functional materials,
Another object of the present invention is to provide a modified porous film that is excellent in hydrophobicity and prevents diffusion of barrier metal when used as a semiconductor material. Furthermore, a porous film modifying method for obtaining such a modified porous film, a semiconductor material comprising the obtained porous film, and a semiconductor device using the semiconductor material are provided. The purpose is to do.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have made a modification with excellent hydrophobicity and mechanical strength by reacting a specific organosilicon compound on the porous film surface without using a metal catalyst. The inventors have found that an improved porous film can be obtained, and have reached the present invention. Furthermore, it has been found that the porous film has a specific pore structure, whereby a modified porous film that prevents diffusion of barrier metal when used for a semiconductor material can be obtained. It came.

That is, the present invention is a method for modifying a porous film in which a porous film mainly having a Si-O bond and an organosilicon compound are contacted under heating without using a metal catalyst,
As the organosilicon compound,
A Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule may be the same or different. ) And two or more Si—X—Si bond units (X is O, NR, C _f H _2f (f is 1 or 2) or C ₆ H ₄
R represents C _g H _{2g + 1} (g is an integer of 1 to 6) or C ₆ H ₅ . An organosilicon compound having one or more) is used.

  Further, it is preferable that the porous film having a narrow part in the pores and the organosilicon compound are brought into contact with each other under heating without using a metal catalyst, and at least a part of the narrow part is blocked.

It is preferable that the porous film and the organosilicon compound are contacted in the presence of H ₂ O.

  The heating temperature is preferably 100 to 600 ° C.

  The porous film preferably has an average pore diameter in the range of 0.5 nm to 10 nm.

  The pore structure of the porous film is preferably a periodic pore structure.

  The crystal structure of the porous film is preferably a zeolite structure.

  It is preferable that the porous film has a diffraction peak having a maximum relative intensity among diffraction peaks measured by an X-ray diffraction method in a range of a plane spacing of 1.3 nm to 13 nm.

  The organosilicon compound is preferably a cyclic siloxane.

The cyclic siloxanes are
Formula (I):

(In the formula, R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF _{3 (CF 2) b (CH} 2) c, shows the _{C d H 2d-1, OC} e H 2e + 1, or a halogen atom, a is an integer of 1-3, b is an integer of 0, c is An integer of 0 to 4, d is an integer of 2 to 4, e is an integer of 1 to 6,
L is an integer of 0 to 8, m is an integer of 0 to 8, n is an integer of 0 to 8, and 3 ≦ L + m + n ≦ 8.
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). )
It is preferable that it is at least 1 sort (s) of the cyclic siloxane compound represented by these.

Further, the organosilicon compound is
General formula (II): YSiR ¹⁰ R ¹¹ ZSiR ¹² R ¹³ Y
(Wherein R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same as or different from each other, and H, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) represents _c , OC _e H _{2e + 1} , or a halogen atom,
a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4, e is an integer of 1 to 6,
Z is O, (CH ₂ ) _d , C ₆ H ₄ , (OSiR ^a R ^b ) _n O, OSiR ^c R ^d QSiR ^e R ^f O, or NR ^g , and R ^a , R ^b , R ^c , R ^d , R ^e and R ^f may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , halogen An atom or OSiR ^h R ⁱ R ^j , a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4; d is an integer of 1 to 2; Is an integer of 10, Q represents (CH ₂ ) _m or C ₆ H ₄ , m is an integer of 1 to 6, and R ^h , R ⁱ and R ^j may be the same or different from each other;
Each represents H or CH ₃ , R ^g represents (CH ₂ ) _p or C ₆ H ₄ , p is an integer of 1 to 6;
Two Ys may be the same or different, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (C
F ₂ ) _b (CH ₂ ) _c , OC _e H _{2e + 1} , or a halogen atom, a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4, e is 1 An integer of ~ 6,
R ^a or R ^b , R ^c or R ^d , R ^e or R ^f appearing in the formula, at least any two of the two Y are H, OH, OC _e H _{2e + 1} (e is 1 to 6) Integer), or a halogen atom.
)
It is also preferable that it is at least 1 type of the organosilicon compound represented by these.

Further, the organosilicon compound is
General formula (III):

(In the formula, R ¹⁵ , R ¹⁶ , R ¹⁸ , R ¹⁹ , R ²¹ , R ²² may be the same as or different from each other, and each of H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , OC _e H _{2e + 1} , or a halogen atom, and R ¹⁷ , R ²⁰ , and R ²³ may be the same as or different from each other, and C ₆ H ₅ , Or C _a H _{2a + 1} , a is an integer of 1 to 2, b is an integer of 0 to 10, and c is 0 to
An integer of 4, e is an integer of 1-6,
L is an integer of 0 to 8, m is an integer of 0 to 8, n is an integer of 0 to 8, and 3 ≦ L + m + n ≦ 8.
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). )
It is desirable that it is at least one of the cyclic silazane compounds represented by

  The modified porous film according to the present invention is obtained by the above modification method.

  The semiconductor material according to the present invention is preferably made of a modified porous film and used as an interlayer insulating film. The semiconductor device according to the present invention is characterized by using a semiconductor material.

  According to the present invention, a porous film having excellent hydrophobicity and mechanical strength that can be used for optical functional materials and electronic functional materials can be provided, and this can be suitably used for an interlayer insulating film as a semiconductor material. it can.

  Further, according to the present invention, when used in a semiconductor material, it is possible to provide a modified porous film capable of preventing the diffusion of a barrier metal, which is an interlayer as a semiconductor material. It can be suitably used for an insulating film.

  The modified porous film excellent in hydrophobicity and mechanical strength according to the present invention is obtained by bringing a specific organosilicon compound into contact with the porous film and reacting the organosilicon compound. Further, by using a porous film having a specific structure, a modified porous film in which diffusion of barrier metal is prevented can be obtained.

  First, the porous film used for the modification treatment will be described.

Porous film The porous film used in the present invention is a porous film mainly having Si-O bonds and may partially contain an organic substance.

  The term “porous” as used in the present invention means a structure having innumerable pores, and the pore opening has a diameter smaller than 100 nm and the pore length is longer than the diameter of the opening. With such a structure, water molecules can freely enter the porous film from the outside through the pores. These pores include voids between the particles.

Further, “mainly having a Si—O bond” is not particularly limited as long as Si atoms are bonded to Si atoms via at least two or more O atoms. For example, hydrogen, halogen, an alkyl group, a phenyl group, or a functional group containing these may be partially bonded to the Si atom. The ratio of Si and O in the porous film is confirmed by elemental analysis by XPS, and is preferably in the range of 0.5 ≦ Si / O (atomic ratio) ≦ 1.0. It is preferable that the weight fraction of Si is 40% by weight or more. Further, the Si—O bond can be confirmed by IR. Typical examples include silica, hydrogenated silsesquioxane, methyl silsesquioxane, hydrogenated methyl silsesquioxane, dimethylsiloxane, and the like. The surface of the porous film may be pretreated with a generally known surface treating agent having a methyl group, hydrogen or the like. For example, a porous film treated with hexamethyldisilazane (HMDS), trimethylsilyl chloride (TMSC), monosilane, or the like can also be used.

  The porous film used in the present invention preferably has mesopores. The average pore diameter is also preferably in the range of 0.5 nm to 10 nm. If it is this range, sufficient mechanical strength and low dielectric constant can be made compatible by the modification | reformation mentioned later.

The average pore diameter of the porous film can be generally measured using a three-sample fully automatic gas adsorption amount measuring device Autosorb-3B type (manufactured by Cantachrome). The measurement in this case is carried out by a nitrogen adsorption method at a liquid nitrogen temperature (77 K), the specific surface area can be obtained by the BET method, and the pore distribution can be obtained by the BJH method.

The porous film to be modified in the present invention is not particularly limited, but (1) a coating solution is prepared by a sol-gel method using alkoxysilanes by the production method, the coating solution is applied to the substrate surface, and then A porous film obtained by drying and baking (hereinafter also referred to as porous film (1)).
(2) Preparing a coating solution containing a composite (self-organized) product of silica sol and an organic compound, applying the obtained coating solution to the substrate surface, and then drying and baking to remove the organic compound. A porous film obtained by the following (hereinafter also referred to as porous film (2)).
(3) A porous film obtained by crystal growth of zeolite on the substrate surface, followed by drying and baking (hereinafter also referred to as porous film (3)).

  The method for producing these porous films will be described below.

Porous film (1)
The porous film (1) is obtained by preparing a coating solution by sol-gel method using alkoxysilanes, applying the coating solution to a substrate, and then drying and baking.

  This production method is not particularly limited as long as a porous film can be obtained, but specifically, it can be produced as follows.

First, a coating solution is prepared by a sol-gel method using alkoxysilanes. Such a coating solution can be obtained by a conventionally known method, specifically, alkoxysilanes, which are components as described later, a catalyst, and water, and further, if necessary, a solvent, It can be obtained by stirring at 0 to 70 ° C., preferably 30 to 50 ° C., for several minutes to 5 hours, preferably 1 to 3 hours.

First, each of the above components will be described.
(Alkoxysilanes)
The alkoxysilanes are not particularly limited, but specific examples include quaternary alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, and tetrabutylsilane;
Tertiary alkoxyfluorosilanes such as trimethoxyfluorosilane, triethoxyfluorosilane, triisopropoxyfluorosilane, tributoxyfluorosilane;
CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC
H ₃ ) ₃ , CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , (CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , (CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , (CF ₃ ) ₂ CF (CF ₂ ) ₈ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ (C ₆ H ₄ ) CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₃ (C ₆ H ₄ ) CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ (C ₆ H ₄ ) CH ₂ CH ₂ Si (OCH ₃ ) ₃ ,
CF ₃ (CF ₂ ) ₇ (C ₆ H ₄ ) CH ₂ CH ₂ Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , (CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , (CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , (CF ₃ ) ₂ CF (CF ₂ ) ₈ CH ₂ CH ₂ SiC
H ₃ (OCH ₃ ) ₂ , CF ₃ (C ₆ H ₄ ) CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , CF ₃ (CF ₂ ) ₃ (C ₆ H ₄ ) CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , CF ₃ (CF ₂ ) ₅ (C ₆ H ₄ ) CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ , CF ₃ (CF ₂ ) ₇ (C ₆ H ₄ ) CH ₂ CH ₂ SiCH ₃ (OCH _{3 2}
CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (
_{OCH 2 CH 3) 3, CF} 3 (CF 2) 7 CH 2 CH 2 Si (OCH 2 CH 3) 3, CF 3 (CF 2) 9 CH 2 CH 2 Si (OCH 2 CH 3) Fluorine-containing ₃ such Alkoxysilanes;
Tertiary alkoxyalkylsilanes such as trimethoxymethylsilane, triethoxymethylsilane, trimethoxyethylsilane, triethoxyethylsilane, trimethoxypropylsilane, triethoxypropylsilane; trimethoxyphenylsilane, triethoxyphenylsilane, trimethoxychlorophenyl Tertiary alkoxyarylsilanes such as silane and triethoxychlorophenylsilane;
Tertiary alkoxy phenethyl silane such as trimethoxy phenethyl silane, triethoxy phenethyl silane;
Secondary alkoxyalkylsilanes such as dimethoxydimethylsilane and diethoxydimethylsilane are exemplified. Of these, tetraethoxysilane is preferably used.

  Alkoxysilanes can be used alone or in combination of two or more.

(catalyst)
As a catalyst used for the preparation of the coating solution, at least one selected from an acid catalyst or an alkali catalyst is used.

  Examples of the acid catalyst include inorganic acids and organic acids.

  Examples of inorganic acids include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, phosphoric acid, boric acid, hydrobromic acid and the like.

  Examples of the organic acid include acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oxalic acid, maleic acid, methylmalonic acid, adipic acid, and sebacic acid. Gallic acid, butyric acid, meritic acid, arachidonic acid, shikimic acid, 2-ethylhexanoic acid, oleic acid, stearic acid, linoleic acid, linolenic acid, salicylic acid, benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, Benzenesulfonic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, tartaric acid, succinic acid, fumaric acid, itaconic acid, mesaconic acid, citraconic acid And malic acid.

  On the other hand, examples of the alkali catalyst include ammonium salts and nitrogen-containing compounds.

  Examples of ammonium salts include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.

  Examples of the nitrogen-containing compound include pyridine, pyrrole, piperidine, 1-methylpiperidine, 2-methylpiperidine, 3-methylpiperidine, 4-methylpiperidine, piperazine, 1-methylpiperazine, 2-methylpiperazine, 1,4-dimethyl. Piperazine, pyrrolidine, 1-methylpyrrolidine, picoline, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicyclooctene, diazabicyclononane, diazabicycloundecene, 2-pyrazoline, 3 -Pyrroline, quinuclidine, ammonia, methylamine, ethylamine, propylamine, butylamine, N, N-dimethylamine, N, N-diethylamine, N, N-dipropylamine, N, - dibutylamine, may be mentioned trimethylamine, triethylamine, tripropylamine, tributylamine and the like.

(solvent)
Examples of the solvent used for preparing the coating solution include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, and i-pentanol. 2-methylbutanol, sec-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, heptanol-3, n- Octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethylheptanol-4, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadeci Alcohol, phenol, cyclohexanol, methyl cyclohexanol, 3,3,5-trimethyl cyclohexanol, benzyl alcohol, phenyl methyl carbinol, diacetone alcohol, mono-alcohol solvents such as cresol;
Ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, pentanediol-2,4, 2-methylpentanediol-2,4, hexanediol-2,5, heptanediol-2,4, 2- Polyhydric alcohol solvents such as ethylhexanediol-1,3, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin;
Acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-i- Ketone solvents such as butyl ketone, trimethylnonanone, cyclohexanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, diacetone alcohol, acetophenone, fenchon;
Ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2-ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane, dimethyldioxane, ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol diethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-n-hexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, Diethylene glycol monoethyl ether, diethylene glycol diethyl ether , Diethylene glycol mono-n-butyl ether, diethylene glycol di-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytriglycol, tetraethylene glycol di-n-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono Ether solvents such as propyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran;
Diethyl carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec -Pentyl, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methyl cyclohexyl acetate, n-nonyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl acetate Ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, propylene glycol monomethyl acetate Chill ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, glycol diacetate, methoxytriglycol acetate, ethyl propionate, N-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, phthalic acid Ester solvents such as diethyl;
Nitrogen-containing solvents such as N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropionamide, N-methylpyrrolidone, etc. Can be mentioned. A solvent can be used combining 1 type (s) or 2 or more types chosen from these.

  A coating solution is prepared using such components. The method for adding these components in preparing the coating solution is arbitrary, and the order of addition is not particularly limited, but preferably, the addition of water to the alkoxysilanes controls the hydrolysis and dehydration condensation of the alkoxysilanes. In order to do this, it is better to do it in two steps. In order to prevent hydrolysis and dehydration condensation from being completed by the first addition of water, 1 mol (molar ratio) of the alkoxy group of water / alkoxysilane is 0.1 to 0.3, preferably 0.2 to 0.25. It is preferable to add water in such an amount. The water addition for the second time may be arbitrary, but it is preferable to add water in such an amount that 1 mol (molar ratio) of alkoxy groups of water / alkoxysilanes = 1-10. The time between the first and second water additions is not particularly limited and can be arbitrarily set.

  The catalyst may be used in any amount as long as the reaction can be promoted, but is preferably added at a molar ratio of alkoxysilanes: catalyst = 1: 0.1 to 0.001. When diluting with a solvent, it is diluted approximately 1 to 100 times, preferably 3 to 20 times.

  A coating solution obtained by adding these alkoxysilanes, a catalyst, water, and a solvent as required, and stirring for several minutes to 5 hours is applied to a substrate to obtain a precursor of a porous film. . Making the film porous can be controlled by changing the type of solvent and alkoxysilane used, and pores are formed by removing the alcohol component generated by solvent evaporation and hydrolysis during drying and baking, thereby obtaining a porous film. It is done.

  As the substrate used for forming the porous film, any substrate can be used as long as it is generally used. For example, glass, quartz, a silicon wafer, stainless steel, etc. are mentioned. Moreover, any shape, such as plate shape and dish shape, may be sufficient.

  Examples of the method of applying to the substrate include general methods such as a spin coating method, a casting method, and a dip coating method. In the case of the spin coating method, a porous film having a uniform film thickness with excellent film surface smoothness is obtained by placing a substrate on a spinner, dropping a sample on the substrate, and rotating the sample at 500 to 10,000 rpm.

  After applying to the substrate, drying and baking are performed to remove the solvent and alcohol components generated by hydrolysis of alkoxysilanes from the coating film. The drying conditions are not particularly limited as long as the solvent and alcohol components can be evaporated. The baking conditions are not particularly limited as long as the condensation of the silanol groups in the film is further promoted by the baking. Therefore, the firing atmosphere can be performed in the air, in an inert gas, or in a vacuum. However, when an H group, a methyl group, or the like is present in the film, it is desirable to bake at a temperature at which these functional groups do not decompose. Specifically, it is preferable to fire in nitrogen in the range of 250 to 450 ° C.

In addition, an organic solvent or a supercritical fluid having a small surface tension can remove the solvent or an alcohol component generated by hydrolysis of alkoxysilanes. In particular, the removal with a supercritical fluid having no surface tension by adjusting the pressure and temperature is preferable because the pores of the film are not crushed and a very porous film can be obtained.
In this way, the porous film (1) is prepared. The porous film (1) is obtained in a self-supporting state or in a state of being fixed to a substrate.

  The pore structure of the obtained porous film (1) is confirmed to be pores of a random shape by cross-sectional TEM observation of the film.

  Moreover, it is confirmed that the average pore diameter of a porous film (1) is the range of 0.5 nm-10 nm by the above-mentioned pore distribution measurement. Moreover, although the thickness of a film changes with manufacturing conditions, it is the range of about 0.05-2 micrometers.

Porous film (2)
The porous film (2) is prepared by preparing a coating solution containing a composite of silica sol and an organic compound, applying the obtained coating solution to the substrate surface, then drying and baking to remove the organic compound. can get.

  Specifically, first, in the process for preparing the porous film (1), an organic compound such as a surfactant is used as a pore forming agent in the process of preparing a coating solution by sol-gel method using alkoxysilanes. Is added to prepare a coating solution. The order of addition of the organic compounds and the stirring time after the addition are not particularly limited as long as a composite with silica sol is formed.

  Moreover, the manufacturing conditions in this manufacturing method are not specifically limited, It can carry out according to a conventionally well-known method. Furthermore, as a board | substrate and alkoxysilane used in this manufacturing method, the above-mentioned board | substrate and alkoxysilane used by the manufacturing method of a porous film (1) can be used.

  As the surfactant, a compound having a long-chain alkyl group and a hydrophilic group can be usually used. The long chain alkyl group preferably has 8 to 24 carbon atoms, more preferably 12 to 18 carbon atoms, and examples of the hydrophilic group include quaternary ammonium salts, amino groups, nitroso Group, hydroxyl group, carboxyl group and the like, among which quaternary ammonium salt or hydroxyl group is desirable.

Specifically, as such a surfactant,
General formula: C _n H _{2n + 1} (N (CH ₃ ) ₂ (CH ₂ ) _m ) _a (CH ₂ ) _b N (CH ₃ ) ₂ C _L H _{2L + 1} X _{(1 + a)}
(Wherein, a is an integer from 0 to 2, b is an integer from 0 to 4, n is an integer from 8 to 24, m is an integer from 0 to 12, L is an integer from 1 to 24, and X is a halide. It is preferable to use an alkylammonium salt represented by an ion, HSO ⁴⁻ or a monovalent organic anion.

  The surfactant represented by the above general formula forms micelles and is regularly arranged. In the present invention, using this micelle as a template, silica and a surfactant form a complex, and when the template is removed, a porous film having uniform and regularly arranged pores can be prepared.

  As the surfactant, a compound having a polyalkylene oxide structure can also be used.

  Examples of the polyalkylene oxide structure include a polyethylene oxide structure, a polypropylene oxide structure, a polytetramethylene oxide structure, and a polybutylene oxide structure.

  Specific examples of the compound having such a polyalkylene oxide structure include polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxybutylene block copolymer, polyoxyethylene polyoxypropylene alkyl ether, polyethylene alkyl ether, polyoxyethylene Ether type compounds such as oxyethylene alkyl phenyl ether; ether ester type compounds such as polyoxyethylene glycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene sorbitol fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, etc. Can be mentioned. In the present invention, the surfactant may be used alone or in combination of two or more selected from these.

  The addition ratio of alkoxysilanes, catalyst, and water is the same as in the case of (1) above, but the addition amount of the surfactant is 0.002 to 1 times, preferably 0.005, to the alkoxysilanes. A molar ratio of ˜0.15 is desirable.

  The form when the surfactant is added is not limited, and any form of a solid state or a state dissolved in a solvent may be used.

  Production of a porous film (2) having a periodic pore structure such as 2D-hexagonal structure, 3D-hexagonal structure, cubic structure, etc. by changing the combination and molar ratio of the surfactant and alkoxysilane. can do.

  In order to obtain a porous film, the coating solution thus prepared is applied to a substrate and dried in the same manner as in the method for producing the porous film (1) described above, and then further baked or an organic solvent. The surfactant may be removed by extraction with.

  The pores of the obtained film can be confirmed to have an average pore diameter of 1 nm to 10 nm by cross-sectional TEM observation or pore distribution measurement of the film. In addition, in the case of having a periodic pore structure such as 2D-hexagonal structure, 3D-hexagonal structure, cubic structure, etc., the relative intensity is in the range of 1.3 to 13 nm in the distance between planes by X-ray diffraction (CuKα). The maximum diffraction peak can be confirmed. Since the porous film (2) has a periodic pore structure, a modified porous film having excellent hydrophobicity and mechanical strength can be easily obtained.

The specific pore structure of the porous film (2) is confirmed by X-ray diffraction (CuKα) and TEM observation of the film cross section.

  The 2D-hexagonal structure is confirmed by honey-crystal-like regular pores observed by TEM observation and a diffraction peak at 2θ = 1 to 10 ° by X-ray diffraction. The 3D-hexagonal structure is confirmed by the fact that three-dimensional regular pores are observed by TEM observation, and a diffraction peak showing a (100) plane at 2θ = 1 to 10 ° is obtained by X-ray diffraction. The cubic structure is confirmed by three-dimensional regular pores observed by TEM observation, and a diffraction peak showing a (200) plane at 2θ = 1 to 10 ° is obtained by X-ray diffraction.

  The obtained film has a pore structure of 3D-hexagonal structure or cubic structure, and in particular, the pore walls in the pores have a narrow portion separated in a range of 1 to 40 mm, preferably 2 to 25 mm. In such a case, the narrow portion can be easily blocked by a modification treatment described later, and a porous film in which at least a part of the narrow pore portion is blocked can be obtained. The measurement of the size of the narrow portion is confirmed by an electron beam structural analysis method. By modifying such a porous film, it is possible to obtain a modified porous film that is excellent in hydrophobicity and that can prevent diffusion of barrier metal when used as a semiconductor material.

  The porous film having a narrow portion in the pore is a porous film having a 2D-hexagonal structure in which a narrow portion is formed in the pore, in addition to the porous film having a 3D-hexagonal structure or a cubic structure. Can be used.

  In order to prepare a porous film having a 2D-hexagonal structure in which narrow portions are formed in the pores, the following procedure is performed.

Specifically, first, a coating solution is prepared by partially hydrolyzing and dehydrating and condensing alkoxysilanes in the presence of a surfactant and silicone oil. It is preferable to prepare a mixed solution by previously mixing a surfactant and silicone oil and add the partially mixed hydrolyzed dehydrated alkoxysilane. Here, “partially” means a state in which the mixed solution is fluidized without gelation. In general, since the viscosity can be regarded as gelation at 10 ⁵ poise, a mixed solution having this viscosity or less is partially hydrolyzed and dehydrated. The partially hydrolyzed and dehydrated condensed state can be obtained by controlling and mixing water below the required amount.

  By preparing the coating solution in this way, it is considered that surfactants are arranged around silicone oil to form micelles. Thereafter, after applying the coating liquid to the substrate and drying, and further removing the surfactant by baking, the silicone oil taken into the center of the micelles adheres to the pore inner surface of the porous film, It is thought that the narrow part of the is formed.

  Although it does not specifically limit as said silicone oil, The organosilicon compound which has polydimethylsiloxane as a main component is mentioned. As such, trimethylsiloxy-terminated polydimethylsiloxane, polyphenylsiloxane and polydimethylsiloxane copolymer, polyphenylmethylsiloxane and polydimethylsiloxane copolymer, poly-3,3,3-trifluoropropylmethylsiloxane and polydimethylsiloxane. Copolymer of siloxane, copolymer of polyethylene oxide and polydimethylsiloxane, copolymer of polypropylene oxide and polydimethylsiloxane, copolymer of polyethylene oxide and polypropylene oxide and polydimethylsiloxane, hydride-terminated polydimethylsiloxane, copolymer of polymethylhydridosiloxane and polydimethylsiloxane And silanol-terminated polydimethylsiloxane. The silicone oil used in the present invention can be used alone or in combination of two or more thereof.

The amount of such silicone oil added is preferably in the range of 1 to 100 parts by weight, more preferably 5 to 50 parts by weight with respect to 100 parts by weight of the alkoxysilanes. When the silicone oil is in the above range, a porous film having the narrow portion in the pores can be easily prepared.

  The coating solution prepared in this manner was applied to the substrate and dried in the same manner as in the method for producing the porous film (1) described above, and then the surfactant was removed by baking to remove the narrow portion. A porous film having a 2D-hexagonal structure is obtained.

  The obtained porous film has a diffraction peak at 2θ = 1 to 10 ° by X-ray analysis (CuKα), and when the cross section of the film is observed with a TEM, honeycomb-like regular pores are recognized. , It was confirmed that the periodic 2D-hexagonal structure was retained, and it was also confirmed that the pore walls in the pores were partially separated by about 1 to 40 mm in the electron beam structural analysis method. Is done.

Porous film (3)
The porous film (3) is obtained by crystal growth of zeolite on the substrate surface, followed by drying and firing.

  As long as a porous film can be obtained, the production method is not particularly limited, and specific examples include the following production methods.

  (A) A coating liquid containing zeolite microcrystals is produced by hydrothermal synthesis of a silica source such as alkoxysilanes or colloidal silica using organic amines as a template. Next, this coating solution is applied to the substrate surface, and the obtained substrate with a coating film is dried and fired under desired conditions to produce a porous film.

  (B) A solution containing zeolite crystallites is produced by hydrothermal synthesis of a silica source such as alkoxysilanes or colloidal silica using organic amines as a template. Further, a surfactant is added to this solution to prepare a coating solution. Next, this coating solution is applied to the substrate surface, and the obtained substrate with a coating film is dried and fired under desired conditions to produce a porous film.

  (C) When a silica source such as alkoxysilanes or colloidal silica is hydrothermally synthesized using organic amines as a template, a substrate is inserted and zeolite is crystal-grown on the substrate surface. Next, a method for producing a porous film by drying and firing a substrate coated with zeolite crystals under desired conditions.

(D) A silica gel is apply | coated to a substrate surface and a board | substrate with a coating film is obtained. Furthermore, a substrate with a coating film is placed in water vapor containing organic amines, and the silica in the coating film is crystallized into zeolite. Next, a method for producing a porous film by drying and firing a substrate coated with zeolite crystals under desired conditions. (Dry gel conversion)
The production conditions in these production methods are not particularly limited, and can be performed according to a conventionally known method.

Examples of the organic amines include tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tripropylamine, triethylamine, triethanolamine, piperidine, cyclohexylamine, neopentylamine, isopropyl Amine, t-butylamine, 2-methylpyridine, N, N′-dimethylbenzylamine, N, N-diethylethanolamine, di (n-butyl) amine, di (n-pentyl) amine, dicyclohexylamine, N, N
-Dimethylethanolamine, choline, N, N-dimethylpiperazine, 1,4-diazabicyclo (2,2,2) octane, N-methyldiethanolamine, N-methylethanolamine, N-methylpiperidine, quinuclidine, N, N ' -Dimethyl-1,4-diazabicyclo (2,2,2) octane dihydroxide, ethylenediamine, 2-imidazolidone and the like.

  The porous film (3) obtained by the production methods (A) to (D) has a diffraction peak unique to zeolite by X-ray diffraction (CuKα), and the crystal structure is a zeolite structure. Is confirmed.

  Moreover, it is confirmed that the average pore diameter of the porous silica film (2) is in the range of 0.5 nm to 10 nm by the above pore distribution measurement.

Method for modifying porous film The method for modifying a porous film of the present invention can be obtained by bringing the porous film as described above into contact with a specific organosilicon compound under heating.

As the organosilicon compound, a linear or cyclic organosilicon compound can be used. As such an organosilicon compound, two Si—A bond units (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom) are included. What has the above is preferable. When a plurality of Si-A bond units are present in the organosilicon compound, A may be the same or different.

In addition, the organosilicon compound used in the present invention has two or more of the above Si-A bond units, and further includes Si—X—Si bond units (X is O, NR, C _f H _2f (f is 1 Or 2) or C ₆ H ₄ , R represents C _g H _{2g + 1} (g is an integer of 1 to 6) or C ₆ H ₅ .
) Is more preferable. When a plurality of Si-A bond units are present in the organosilicon compound, A may be the same or different, and when a plurality of Si-X-Si bond units are present, X may be the same or different. Good.

  The organosilicon compound can be used as long as it has a vapor pressure in any temperature range of 100 to 600 ° C. and does not decompose in the presence of only the compound. In addition, the organosilicon compound needs to have a molecular diameter that sufficiently diffuses into the pores of the porous film. The molecular weight is preferably 900 or less, 70 or more, and 600 or less, 120 or more. More preferred are those of 300 or less and 170 or more. Examples of such organosilicon compounds include cyclic organosilicon compounds such as cyclic siloxane and cyclic silazane, and other acyclic organosilicon compounds. Of these, cyclic siloxane is preferred.

Specifically, as such an organosilicon compound,
Formula (I):

(In the formula, R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF _{3 (CF 2) b (CH} 2) c, shows the _{C d H 2d-1, OC} e H 2e + 1, or a halogen atom, a is an integer of 1-3, b is an integer of 0, c is An integer of 0 to 4, d is an integer of 2 to 4, e is an integer of 1 to 6,
L is an integer of 0 to 8, m is an integer of 0 to 8, n is an integer of 0 to 8, and 3 ≦ L + m + n ≦ 8.
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). It is preferable that it is at least 1 sort (s) of the cyclic siloxane compound represented by this.

  More preferably, the following general formula

(Wherein R ¹ and R ² may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , _{C d H 2d-1, OC} e H 2e + 1, or a halogen atom, a is 1 to 3 integers, b is an integer of 0, c is an integer of 0 to 4, d is 2 to 4 An integer, e is an integer from 1 to 6,
p is an integer of 3 to 8,
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). )
At least one cyclic siloxane represented by the formula is desirable.

  Specific examples of the organosilicon compound represented by the above formula (I) include (3,3,3-trifluoropropyl) methylcyclotrisiloxane, triphenyltrimethylcyclotrisiloxane, 1,3,5 , 7-tetramethylcyclotetrasiloxane, octamethylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenylcyclotetrasiloxane, tetraethylcyclotetrasiloxane, pentamethylcyclopentasiloxane Cyclic siloxanes such as In particular, 1,3,5,7-tetramethylcyclotetrasiloxane is preferred. The organosilicon compound can be used alone or in combination of two or more.

Moreover, as an organosilicon compound,
General formula (II): YSiR ¹⁰ R ¹¹ ZSiR ¹² R ¹³ Y
(Wherein R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same as or different from each other, and H, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) represents _c , OC _e H _{2e + 1} , or a halogen atom,
a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4, e is an integer of 1 to 6,
Z is O, (CH ₂ ) _d , C ₆ H ₄ , (OSiR ^a R ^b ) _n O, OSiR ^c R ^d QSiR ^e R ^f O, or NR ^g , and R ^a , R ^b , R ^c , R ^d , R ^e and R ^f may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , halogen An atom or OSiR ^h R ⁱ R ^j , a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4; d is an integer of 1 to 2; Is an integer of 10, Q represents (CH ₂ ) _m or C ₆ H ₄ , m is an integer of 1 to 6, and R ^h , R ⁱ and R ^j may be the same or different from each other;
Each represents H or CH ₃ , R ^g represents (CH ₂ ) _P or C ₆ H ₄ , p is an integer of 1 to 6;
Two Ys may be the same or different, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (C
F ₂ ) _b (CH ₂ ) _c , OC _e H _{2e + 1} , or a halogen atom, a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4, e is 1 An integer of ~ 6,
R ^a or R ^b , R ^c or R ^d , R ^e or R ^f appearing in the formula, at least any two of the two Y are H, OH, OC _e H _{2e + 1} (e is 1 to 6) Integer), or a halogen atom.
)
It is also preferable that it is at least 1 type of the organosilicon compound represented by these.

Specific examples of the organosilicon compound represented by the above formula (II) include 1,2-bis (tetramethyldisiloxanyl) ethane, 1,3-bis (trimethylsiloxy) -1,3-dimethyldi Siloxane, 1,1,3,3-tetraisopropyldisiloxane, 1,1,4,4-tetramethyldisilethylene, 1,1,3,3-tetramethyldisiloxane, 1,1,3,3- Tetraethyldisiloxane, 1,1,3,3-tetraphenyldisiloxane, 1,1,4,4-tetramethyldisylethylene, 1,1,3,3,5,5-hexamethyltrisiloxane, 1,3,3,5,5-hexaethyltrisiloxane, 1,1,3,3,5,5-hexaisopropyltrisiloxane, 1,1,3,3,5,5,7,7-octamethyl Tetrasiloxane, 1,1 1,3,5,5-hexamethyltrisiloxane, 1,1,1,3,3,5,7,7-octamethyltetrasiloxane, 1,3-dimethyltetramethoxydisiloxane, 1,1,3, Examples thereof include siloxane compounds such as 3-tetramethyl-1,3-diethoxydisiloxane, 1,1,3,3,5,5-hexamethyldiethoxytrisiloxane, and tetramethyl-1,3-dimethoxydisiloxane. . The organosilicon compound can be used alone or in combination of two or more.

  Further, as the organosilicon compound, the general formula (III):

(In the formula, R ¹⁵ , R ¹⁶ , R ¹⁸ , R ¹⁹ , R ²¹ , R ²² may be the same as or different from each other, and each of H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , OC _e H _{2e + 1} , or a halogen atom, and R ¹⁷ , R ²⁰ , and R ²³ may be the same as or different from each other, and C ₆ H ₅ , Or C _a H _{2a + 1} , a is an integer of 1 to 2, b is an integer of 0 to 10, and c is 0 to
An integer of 4, e is an integer of 1-6,
L is an integer of 0 to 8, m is an integer of 0 to 8, n is an integer of 0 to 8, and 3 ≦ L + m + n ≦ 8.
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). )
It is also preferable that it is at least 1 type of the cyclic silazane compound represented by these.

Specific examples of the organosilicon compound represented by the above formula (III) include 1, 2, 3, 4
, 5,6-hexamethylcyclotrisilazane, 1,3,5,7-tetraethyl-2,4,6,8-tetramethylcyclotetrasilazane, 1,2,3-triethyl-2,4,6-triethyl And cyclic silazane compounds such as cyclotrisilazane. The organosilicon compound can be used alone or in combination of two or more.

In the present invention, the organosilicon compound is an organosilicon compound represented by the above general formula (I), a siloxane compound represented by the general formula (II), or a cyclic silazane compound represented by the general formula (III). It can be used alone or in combination of two or more. In these, it is preferable to use the cyclic siloxane represented by general formula (I).

  The method for modifying a porous film according to the present invention is carried out by bringing the above-mentioned porous film and an organosilicon compound into contact with each other under heating and causing the organosilicon compound to react on the surface of the porous film. Such modification of the porous film can be carried out in a liquid phase or a gas phase atmosphere.

  When the reaction is carried out in the liquid phase, it may be carried out using an organic solvent. Examples of organic solvents that can be used include alcohols such as methanol, ethanol, n-propyl alcohol, and isopropyl alcohol; ethers such as diethyl ether, diethylene glycol dimethyl ether, 1,4-dioxane, and tetrahydrofuran; aryls such as benzene, toluene, and xylene. Examples include alkanes. In the case of treatment in an organic solvent, the concentration of the organosilicon compound is not particularly limited and can be carried out at any concentration.

  When the reaction is carried out in the gas phase, the organosilicon compound may be diluted with a gas. Dilution gases that can be used include air, nitrogen, argon, hydrogen and the like. Moreover, it is also possible to carry out under reduced pressure instead of diluting with gas. In particular, it is preferable to carry out in a gas phase atmosphere because solvent recovery and a drying step are unnecessary. When diluting the organosilicon compound, the concentration of the organosilicon compound is not particularly limited as long as it is 0.1 vol% or more. Further, the reaction gas arbitrarily diluted can be carried out by any method, whether it is brought into contact in circulation, brought into contact by recycling, or brought into contact in a sealed container.

  The reaction temperature (heating temperature) between the organosilicon compound and the porous film is preferably in the range of 100 to 600 ° C, more preferably in the range of 300 to 450 ° C. Heating is not particularly limited as long as the temperature of the porous film can be made uniform, whether it is a hot plate type or an electric furnace type. If the reaction temperature is within this range, the reaction does not proceed because the temperature is low, and the reaction proceeds efficiently without causing side reactions due to the temperature being too high.

  There is no particular problem in raising the temperature of the porous film even if it is gradually heated to the reaction temperature or inserted into the reaction film at once. It is also possible to fire after the porous film is fired. Although the time required for the modification of the porous film depends on the reaction temperature, it is usually several minutes to 40 hours, preferably 10 minutes to 24 hours.

  The improvement in hydrophobicity and mechanical strength in the modification method of the present invention is presumed to be mainly due to the reaction between the silanol groups present on the porous film surface and the organosilicon compound. This silanol group is generally present on the surface of a porous film mainly having Si—O bonds. In particular, in the case of a porous material, many silanol groups are present inside the pores. In addition to the method of the present invention, silanol groups can be reduced by introducing a hydrophobic group or the like, but it is still difficult to completely remove the silanol groups by heat treatment up to 600 ° C.

Moreover, since the dehydration reaction further proceeds as the heat treatment temperature rises, silanol groups present on the surface of the porous film are reduced. Therefore, heating the porous film in the presence of H ₂ O increases the silanol groups by hydrolysis, so that the organosilicon compound is likely to react, and for the modification treatment that improves hydrophobicity and mechanical strength. Is preferred.

For the above reasons, the modification treatment is also preferably performed in the presence of H ₂ O when the organosilicon compound and the porous film are brought into contact with each other. Since the reaction is promoted by the contact in the presence of H ₂ O, a modified porous film excellent in hydrophobicity and mechanical strength can be obtained efficiently. The addition amount of H ₂ O is used so as to be a predetermined amount depending on the kind of the organosilicon compound that reacts with the porous film, but a range corresponding to a partial pressure of 0.05 to 25 kPa is preferable. If it is within this range, there is no case where the reaction promoting effect cannot be obtained due to too little addition of H ₂ O. Moreover, there is no adverse effect such as collapse of the pore structure due to too much. The temperature of adding H ₂ O is not particularly limited as long as the following reaction temperature. The addition method is not particularly limited, but it is preferably added before contact with the organosilicon compound.

  The porous film is improved in hydrophobicity and mechanical strength by contacting with such an organosilicon compound under heating. That is, the organosilicon compound reacts on the surface of the porous film and is bonded to the film surface, or is polymerized with other organosilicon compounds, or polymerized with organosilicon compounds. At least a part of the surface is coated with the reactant, and as a result, not only the hydrophobicity is developed, but also the mechanical strength is improved. The porous film surface here refers not only to the outer surface of the film but also to the inner surface of the pores.

  The mechanism of such modification of the porous film is not clear, but the silanol group on the film surface and the organosilicon compound are first bonded, and then the organosilicon compound and the unreacted organosilicon compound react (polymerization). Thus, it is presumed that the siloxane polymer grows and further bonds with an organosilicon compound or siloxane polymer bonded to another surface. When such a reaction takes place in the pores, the reacted organosilicon compound coats the surface of the film pores in a cocoon-like structure, and in the pores with a pore diameter of several nm. Is presumed to form a bridge-like structure. Such a unique structure formed in the pores is presumed to have manifested mechanical strength that was not conventionally known, while at the same time expressing hydrophobicity.

  Therefore, this reaction needs to proceed on the pore inner surface of the film. Therefore, it is desirable that the catalyst does not exist in the gas phase at a reaction temperature of 100 to 600 ° C., and it is not preferable that the catalyst be present together with the organosilicon compound before the reaction. In the case where the catalyst is a metal, the metal remains in the modified film, and the relative dielectric constant increases, which is not particularly preferable. Therefore, it is preferable to contact the porous film and the organosilicon compound under heating in an atmosphere substantially free of a metal catalyst.

  On the other hand, it is considered that the presence of the catalyst in the porous silica is not particularly a problem, but when the catalyst is a metal, the metal remains in the film, which increases the dielectric constant. Therefore, it is not preferable.

  In the hydrophobization method using a silylating agent other than the organosilicon compound used in the present invention, for example, hexamethyldisilazane (HMDS), only the silanol group on the film surface is changed to a trimethylsilyl group. It is estimated that the strength hardly improves.

Therefore, conventional silane compounds are insufficient as reinforcing agents. Therefore, in order to improve both hydrophobicity and mechanical strength, the Si—A bond unit (A is H, OH, OC _e H _{2e + 1).}
(E is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule may be the same or different. ) And two or more Si—X—Si bond units (X is O, NR, C _f H _2f (f is an integer of 1 to 6) or C ₆ H ₄ , and R is C _g H It is particularly preferable to react an organosilicon compound having one or more of _{2g + 1} (g is 1 or 2) or C ₆ H ₅ .

  As this Si-A bond unit, a Si-H bond is particularly preferable. In other words, organosilicon compounds react with water to form Si—OH, which reacts with other —OH groups to cause dehydration condensation. Direct dehydrogenation reaction occurs with the Si-OH group. The organosilicon compound may have an —OH group from the beginning, but in this case, it is estimated that the rate of reaching the inside of the pore and reacting with the inside surface of the pore becomes small.

  Furthermore, in the functional group A of the Si—A bond unit, when the reactivity is compared between hydrogen, an alkoxy group, and halogen, the order is halogen> alkoxy group> hydrogen. As functional groups, those having a low boiling point and being easy to handle and those having little steric hindrance and easy diffusion are desired. When halogen is used for the functional group A of the Si-A bond unit, since the halogen easily reacts, it reaches the inside of the pore as described above, and the proportion of the organosilicon compound that reacts with the inside surface of the pore decreases. Seem. In addition, organosilicon compounds having an alkoxy group are slow to diffuse into mesopores due to steric hindrance, and the alcohol produced by the reaction interacts with water and Si-OR reacts with water. It seems to inhibit. From the above, when the Si—A bond unit of the organosilicon compound is Si—H, the modified organosilicon compound of the present invention has particularly excellent effects on hydrophobicity and mechanical strength.

  The porous film used for obtaining a modified porous film excellent in hydrophobicity and mechanical strength of the present invention may be a free-standing film or a film formed on a substrate. Moreover, since the porous film used by this invention does not generate | occur | produce defects, such as cloudiness and coloring, after reaction with an organosilicon compound, it can be used also when a transparent thing is required.

  The hydrophobicity of the porous film modified in the present invention is confirmed by measuring the relative dielectric constant. The relative permittivity is measured by forming an aluminum electrode by vapor deposition on the surface of the porous film on the substrate and the back surface of the silicon wafer used for the substrate, and at a frequency of 100 kHz in an atmosphere of 25 ° C. and 50% relative humidity. Can be done by law. Further, the mechanical strength of the porous film is confirmed by measuring the elastic modulus of the film by nanoindentation measurement.

  Since the modified porous film of the present invention is excellent in both hydrophobicity and mechanical strength, optical functions such as interlayer insulating films, molecular recording media, transparent conductive films, solid electrolytes, optical waveguides, LCD color members, etc. It can be used as a material or an electronic functional material. In particular, an interlayer insulating film as a semiconductor material is required to have strength, heat resistance, and low dielectric constant, and such a porous film excellent in hydrophobicity and mechanical strength is preferably applied.

  On the other hand, even in a porous film having narrow portions in the pores, the porous film is modified by the same method as the above-described modification method. The modified porous film has improved hydrophobicity, and when used as a semiconductor material, it can prevent diffusion of barrier metal and prevent a decrease in dielectric constant.

  Although the mechanism by which such an effect is obtained is not clear, siloxanes are polymerized on the silica surface inside the pores, so that the surface is coated with a thin film of siloxane having a hydrophobic functional group. It is presumed that at least a part of the separated narrow part is blocked by siloxane.

  In the porous film in which at least a part of the narrow pore portion of the present invention is blocked, the narrow pore portion is blocked and the improvement in hydrophobicity is measured by measuring the relative dielectric constant and TEM observation of the film cross section. Confirmed by The relative dielectric constant can be measured by the above method.

  A barrier film made of titanium nitride (TiN), tantalum nitride (TaN), or the like is formed on the porous film surface by vapor deposition (CVD) or sputtering, and then a TEM observation of the film cross section is performed. Thus, diffusion of the metal can be confirmed.

  Since the porous film in which at least a part of the narrow pore portion of the present invention is blocked is excellent in both barrier metal diffusion prevention and hydrophobicity, a semiconductor material such as an interlayer insulating film, an inter-wiring insulating film, and a barrier film; Optical functional materials such as molecular recording media, transparent conductive films, solid electrolytes, optical waveguides, LCD color members, and electronic functional materials. In particular, interlayer insulating films and inter-wiring insulating films made of semiconductor materials are required to have barrier metal intrusion prevention and hydrophobicity. Such barrier metal intrusion is prevented, and the narrow pores having excellent hydrophobicity are required. A porous film at least partially blocked is preferably used.

  Next, an example of a semiconductor device using the modified porous film of the present invention as an interlayer insulating film will be specifically described.

  First, as described above, a porous film is formed on the surface of a silicon wafer, and the porous film is reacted with an organosilicon compound to be modified. The modified porous film is then etched according to the pattern of the photoresist. After etching the porous film, a barrier film made of titanium nitride (TiN), tantalum nitride (TaN), or the like is formed on the surface of the porous film and the etched portion by a vapor phase growth method.

Thereafter, a copper film is formed by a metal CVD method, a sputtering method, or an electrolytic plating method, and an unnecessary copper film is removed by CMP (Chemical Mechanical Polishing) to create a circuit wiring. Next, a cap film (for example, a film made of silicon carbide) is formed on the surface. Further, if necessary, a semiconductor device according to the present invention can be manufactured by forming a hard mask (for example, a film made of silicon nitride) and repeating the above steps to form a multilayer.

[Example]
EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.

In addition, the following were used for the raw material used by the Example and the comparative example.
<Tetraethoxysilane>
High purity chemical research institute EL grade: Si (OC ₂ H ₅ ) ₄
<Ethanol>
Wako Pure Chemical Industries, Ltd.
Wako Pure Chemical Industries, Ltd. For ultra-trace analysis <Poly (alkylene oxide) block copolymer>
70 g of HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H (Pluronic P123 manufactured by BASF) is weighed and dissolved in 700 g of the above-mentioned ethanol for electronics industry. This was ion-exchanged using an ion exchange resin SK1BH manufactured by Nippon Nensui, and demetallized by removing ethanol by distillation and used. HO (CH ₂ CH ₂ O) ₁₀₆ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₁₀₆ H (Pluronic F127 manufactured by BASF), HO (CH ₂ CH ₂ O) ₃₉ (C ₂ H ₄ CH (CH ₃ ) O) ₄₇ (CH ₂ CH ₂ O) ₃₉ H (manufactured by Mitsui Takeda Chemical Co., Ltd.) was also used after demetalization.
<Water>
Water demetallized with a pure water production apparatus manufactured by Milipore was used.
<N, N-dimethylacetamide>
Kanto Chemical Co., Ltd. for electronic industry [Example 1]
(Preparation of coating solution)
Tetraethoxysilane [TEOS: Si (OC ₂ H ₅ ) ₄ ] 10.0 g and ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] 10 mL at room temperature were added. 1N hydrochloric acid [Wako Pure Chemical Industries, Ltd .: HCl] 1.0 mL was added and stirred, and then ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] 40 mL was added. Stir and mix uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

(Film formation)
Each of the prepared coating solutions is placed on the surface of an 8-inch silicon wafer, applied to the silicon wafer surface by rotating at 2000 rpm for 10 seconds, dried at 100 ° C. for 1 hour, and further baked at 400 ° C. for 3 hours. A porous film was prepared.

(Modification of porous film)
The above porous film was packed in a quartz reaction tube, and under a flow of N ₂ gas of 500 mL / min, 4
It was left (dried) at 00 ° C. for 30 minutes. Thereafter, N ₂ gas was passed through an evaporator at 25 ° C. containing 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by AMAX Co., Ltd.), and 1, 3, 5 together with N ₂ gas was put into the reaction tube , 7-tetramethylcyclotetrasiloxane, 400
The reaction was carried out at ° C. After 1 hour, the introduction of 1,3,5,7-tetramethylcyclotetrasiloxane was stopped, and the reaction tube was cooled to 30 ° C. under a flow of N ₂ gas of 500 mL / min to obtain a modified porous film. . The average pore diameter of the porous film was 1.5 nm. The average pore diameter was measured by a nitrogen adsorption method at 77 K under a liquid nitrogen temperature using a three-sample fully automatic gas adsorption amount measuring device Autosorb-3B type (manufactured by Cantachrome).

(Measurement of dielectric constant and elastic modulus)
The relative dielectric constant was measured by forming an aluminum electrode by vapor deposition on the surface of the porous film on the substrate and the back surface of the silicon wafer used for the substrate to form a metal-insulating film-silicon structure, 25 ° C., relative humidity 50 % Of the electric capacity measured in the range of −40 V to 40 V in a frequency of 100 kHz and the film thickness measured with a Dicktack film thickness meter.

  The elastic modulus of the porous film was confirmed by measuring the elastic modulus of the film by nanoindenter measurement. The nanoindenter measurement was performed using a Triboscope system manufactured by Hystron.

  Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 2]
Tetraethoxysilane [TEOS: Si (OC ₂ H ₅ ) ₄ ] 10.0 g and ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] 10 mL at room temperature After mixing, 1.0 mL of 1N hydrochloric acid [manufactured by Wako Pure Chemical Industries, Ltd .: HCl] was added and stirred, and then poly (alkylene oxide) block copolymer [Pluronic manufactured by BASF Corp.] was added to this solution.
_{P123, HO (CH 2 CH 2} O) 20 (CH 2 CH (CH 3) O) 70 (CH 2 CH 2 O) 20 H] 2.8
A solution prepared by dissolving g in 40 mL of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] was added and stirred, and mixed uniformly. Further, 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a periodic 2D-hexagonal structure with an interplanar spacing of 7.0 nm by X-ray diffraction measurement. The average pore diameter of the porous film was 5.8 nm. Further, the porous film was modified in the same manner as in Example 1. Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 3]
10.0 g of tetraethoxysilane [TEOS: Si (OC ₂ H ₅ ) ₄ ] manufactured by Kojundo Chemical Laboratory Co., Ltd. and 10 ml of ethanol [C ₂ H ₅ OH manufactured by Wako Pure Chemical Industries, Ltd.] After mixing, 1.0 ml of 1N hydrochloric acid was added and stirred to obtain component solution (A). Also, tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ ] 0.13 g and 2- (methoxy (polyethyleneoxy) propyl) trimethylsilane [manufactured by AMAX Co .: CH ₃ O (CH ₂ CH ₂ O) _6-9 (CH ₂ ) ₃ Si (OCH ₃ ) ₃ ] After 0.14 g and 10 ml of ethanol were mixed and stirred, 0.0035 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (B). Furthermore, a poly (alkylene oxide) block copolymer (manufactured by Mitsui Takeda Chemical Co., Ltd .: HO (CH ₂ CH ₂ O) ₃₉ (C ₂ H ₄ CH (CH ₃ ) O) ₄₇ (CH ₂ CH ₂ O) ₃₉ H ) 2.9 g was dissolved in 30 ml of ethanol to obtain a component solution (C). To this (C) component solution, the (B) component solution was added and stirred. Next, the mixed solution of the component solution (C) and the component solution (B) was added to the component solution (A) and stirred, and mixed uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film was confirmed to be 3D-cubic by X-ray diffraction. Moreover, the average pore diameter of the porous film was 5.3 nm. Further, the porous film was modified in the same manner as in Example 1. Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 4]
While 10.0 g of tetraethoxysilane was vigorously stirred, 2.7 g of tetrapropylammonium hydroxide dissolved in 15 g of water was added dropwise thereto, followed by aging at 30 ° C. for 3 days while stirring at room temperature. The obtained transparent and uniform solution was put into a Teflon (R) -coated autoclave and heated at 80 ° C. for 3 days with stirring. As a result, microcrystals were obtained. The obtained microcrystals were collected by a centrifuge and washed with ion-exchanged water and centrifuged until pH <8. Next, 2.8 g of a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] Ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅
OH] A solution obtained by dissolving in 40 mL was added to obtain a coating solution containing zeolite microcrystals.

A porous film was prepared in the same manner as in Example 1. The obtained porous film was confirmed to have a zeolite structure by X-ray diffraction. The porous film had pores having a peak at 7.1 nm in addition to the pores derived from zeolite. Further, the porous film was modified in the same manner as in Example 1. Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 5]
After mixing 10.0 g of tetraethoxysilane and 10 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (A). .
Further, tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ ] 0.13 g and 2- (methoxy (polyethyleneoxy) propyl) trimethylsilane [manufactured by AMAX Co .: CH ₃ O (CH ₂ CH ₂ O) _6-9 (CH ₂ ) ₃ Si (OCH ₃ ) ₃ ] 0.14 g and methyltriethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CH ₃ Si (OC ₂ H ₅ ) ₃ ] 0.06
1 g of ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] 10 ml was mixed and stirred, then 0.0035 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (B). Furthermore, 2.8 g of a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is added. Dissolved in 30 ml of ethanol to obtain a component solution (C). To this (C) component solution, the (B) component solution was added and stirred. Next, the mixed solution of the component solution (C) and the component solution (B) was added to the component solution (A), stirred, and mixed uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 5.5 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 6]
After mixing 10.0 g of tetraethoxysilane and 10 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (A). .
Further, tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ ] 0.60 g and 2- (methoxy (polyethyleneoxy) propyl) trimethylsilane [manufactured by AMAX Co .: CH ₃ O (CH ₂ CH ₂ O) _6-9 (CH ₂ ) ₃ Si (OCH ₃ ) ₃ ] 0.63g,
Methyl triethoxysilane [Tokyo Chemical Industry Co., _{Ltd.: CH 3 Si (OC 2 H} 5) 3] 0.1
4 g and 10 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] were mixed and stirred, and 0.046 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (B). Furthermore, 2.8 g of a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is added. Dissolved in 30 ml of ethanol to obtain a component solution (C). To this (C) component solution, the (B) component solution was added and stirred. Next, the mixed solution of the component solution (C) and the component solution (B) was added to the component solution (A), stirred, and mixed uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. The average pore size of the porous film was 5.2 nm. Further, the porous film was modified in the same manner as in Example 1. Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 7]
After mixing 10.0 g of tetraethoxysilane and 10 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (A). .
Further, tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ ] 0.13 g and 2- (methoxy (polyethyleneoxy) propyl) trimethylsilane [manufactured by AMAX Co .: CH ₃ O (CH ₂ CH ₂ O) _6-9 (CH ₂ ) ₃ Si (OCH ₃ ) ₃ ] 0.14 g,
After mixing and stirring with 10 ml of ethanol, 0.0014 ml of 1N hydrochloric acid was added and stirred, and (B)
A component solution was obtained. Furthermore, a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (C
2.8 g of H ₂ CH ₂ O) ₂₀ H] in ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] 30 m
1 to obtain a component solution (C). To this (C) component solution, the (B) component solution was added and stirred. Next, the mixed solution of the component solution (C) and the component solution (B) was added to the component solution (A), stirred, and mixed uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 5.5 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 8]
After mixing 10.0 g of tetraethoxysilane and 10 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (A). .
Further, tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ ] 0.20 g and 2- (methoxy (polyethyleneoxy) propyl) trimethylsilane [manufactured by Amax Co .: CH ₃ O (CH ₂ CH ₂ O) _6-9 (CH ₂ ) ₃ Si (OCH ₃ ) ₃ ] 0.21 g,
Ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] was mixed and stirred, and then 0.021 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (B). Furthermore, 2.8 g of a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is added. Dissolved in 30 ml of ethanol to obtain a component solution (C). To this (C) component solution, the (B) component solution was added and stirred. Next, the mixed solution of the component solution (C) and the component solution (B) was added to the component solution (A), stirred, and mixed uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. The average pore diameter of the porous film was 5.4 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 9]
After mixing 10.0 g of tetraethoxysilane and 10 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (A). .
Further, tridecafluoro-1,1,2,2-tetrahydrooctyl-1-triethoxysilane [manufactured by Tokyo Chemical Industry Co., Ltd .: CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ ] 0.07 g and 2- (methoxy (polyethyleneoxy) propyl) trimethylsilane [manufactured by AMAX Co .: CH ₃ O (CH ₂ CH ₂ O) _6-9 (CH ₂ ) ₃ Si (OCH ₃ ) ₃ ] 0.07g,
Ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] was mixed and stirred, and then 0.007 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (B). Furthermore, 2.8 g of a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is added. Dissolve in 30 ml of ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] to obtain a component solution (C). To this (C) component solution, the (B) component solution was added and stirred. Next, the mixed solution of the component solution (C) and the component solution (B) was added to the component solution (A), stirred, and mixed uniformly. 8 mL of water was added to this solution and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 5.5 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 10]
8.1 g of tetraethoxysilane, 1.5 g of methyltriethoxysilane, and ethanol 8
After mixing with ml, 1.0 ml of 1N hydrochloric acid was added and stirred to obtain a component solution (A). Further, 2.8 g of a poly (alkylene oxide) block copolymer [BARON's Pluronic P123: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is ethanol. [Wako Pure Chemical Industries, Ltd.: C ₂ H ₅ OH] was dissolved in 32 ml, to obtain component (B) solution. The component solution (B) was added to the component solution (A) and stirred. To this solution, 8 g of water was added and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 4.9 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 11]
After mixing 5.1 g of tetraethoxysilane, 3.6 g of methyltriethoxysilane, and 8 ml of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred ( A) A component solution was obtained. Further, 2.8 g of a poly (alkylene oxide) block copolymer [BARON's Pluronic P123: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is ethanol. [Wako Pure Chemical Industries, Ltd.: C ₂ H ₅ OH] was dissolved in 32 ml, to obtain component (B) solution. The component solution (B) was added to the component solution (A) and stirred. To this solution, 8 g of water was added and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 4.9 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 12]
After mixing 8.1 g of tetraethoxysilane and 1.4 g of dimethyldiethoxysilane and 8 ml of ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred. A component solution (A) was obtained. Also, poly (alkylene oxide) block copolymer [BASF's Pluronic P123: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ )
_{O) 70 (CH 2 CH 2} O) 20 H] 2.8g of ethanol [Wako Pure Chemical Industries, Ltd.: C ₂ H ₅ OH
It was dissolved in 32 ml to obtain a component solution (B). The component solution (B) was added to the component solution (A) and stirred. To this solution, 8 g of water was added and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film retained a 2D-hexagonal structure by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 5.0 nm. Further, the porous film was modified in the same manner as in Example 1.
Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 13]
After mixing 5.0 g of tetraethoxysilane and 3.6 g of dimethyldiethoxysilane and 8 ml of ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], 1.0 ml of 1N hydrochloric acid was added and stirred. A component solution (A) was obtained. To this component (A) solution, a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (
2.8 g of CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] is dissolved in 32 ml of ethanol [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH], and component (B) A solution was obtained. To this (B) component solution, 8 g of water was added and stirred to obtain a transparent and uniform coating solution.

A porous film was prepared in the same manner as in Example 1. The obtained porous film did not show clear regularity by X-ray diffraction measurement. Moreover, the average pore diameter of the porous film was 4.9 nm. Further, the porous film was modified in the same manner as in Example 1. Table 1 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 14]
The porous film was modified in the same manner as in Example 2 except that water vapor was mixed into the introduced gas by passing the introduced gas through an evaporator of water at 25 ° C. Table 2 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 15]
The porous film was modified in the same manner as in Example 2 except that the modification treatment temperature at 400 ° C. was 250 ° C. Table 2 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 16]
The porous film was modified in the same manner as in Example 2 except that the modification treatment time for 30 minutes was changed to 5 minutes. Table 2 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 17]
The modifying agent is changed from 1,3,5,7-tetramethylcyclotetrasiloxane to 1,1,3,3,5,
The porous film was modified in the same manner as in Example 2 except that it was changed to 5-hexamethyltrisiloxane (manufactured by Amax Co., Ltd.). Table 2 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 18]
From the flow equation in which 1,3,5,7-tetramethylcyclotetrasiloxane is introduced into the reaction tube together with N ₂ gas at 500 mL / min, 1,3,5,7-tetramethylcyclotetrasiloxane is introduced into the system. The porous film was modified in the same manner as in Example 2 except that the batch type was changed to 5 vol%. Table 2 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 19]
Implementation was performed except that the modifying agent was changed from 1,3,5,7-tetramethylcyclotetrasiloxane to 1,2,3,4,5,6-hexamethylcyclotrisilazane (manufactured by Amax Co., Ltd.) The porous film was modified in the same manner as in Example 2. Table 2 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Example 20]
After mixing and stirring 10.0 g of tetraethoxysilane and 10 mL of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] at room temperature, 1.0 mL of 1N hydrochloric acid and 10.0 mL of water were added and stirred. [Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] Poly (alkylene oxide) block copolymer dissolved in 60 mL [BASF's Pluronic F127: HO (CH ₂ CH ₂ O) ₁₀₆ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₁₀₆ H] was added and stirred and stirred to obtain a transparent and uniform coating solution.

  A porous film was prepared and modified in the same manner as in Example 1.

  The porous film before the modification retained a periodic cubic structure with an interplanar spacing of 83 nm by X-ray diffraction measurement. The relative dielectric constant of this film was k = 5.6. Furthermore, the pore diameter was calculated | required from the electron density distribution calculated | required by Fourier-transforming an electron diffraction point using the ultra high resolution analytical electron microscope (HREM) (model JEM-3010, product made by JEOL) (electron beam structure analysis method). ) As a result, the pore had a narrow portion having a pore diameter of about 15 mm. The average pore diameter of the porous film was 7.0 nm.

This porous film was modified in the same manner as in Example 1. The dielectric constant of the modified porous film was k = 2.1. Further, the modified porous film is put into a vacuum chamber, 10% pentakis (ethylmethylamide) tantalum-containing isopropyl alcohol vapor and NH ₃ gas are introduced into the chamber, and the reaction pressure is 5 Torr, the reaction temperature is 400 ° C., and TaN. Was formed on a porous film. When the cross-sectional TEM observation of the porous film after TaN film formation was carried out, the diffusion of TaN was not confirmed in the pores.

[Example 21]
After 10.4 g of tetraethoxysilane and 10 mL of ethanol [manufactured by Wako Pure Chemical Industries, Ltd .: C ₂ H ₅ OH] were mixed and stirred at room temperature, 1.0 mL of 1N hydrochloric acid and 10.0 mL of water were added and stirred. After stirring, 2.8 g of a poly (alkylene oxide) block copolymer [Pluronic P123 manufactured by BASF: HO (CH ₂ CH ₂ O) ₂₀ (CH ₂ CH (CH ₃ ) O) ₇₀ (CH ₂ CH ₂ O) ₂₀ H] , 1.5 g of block copolymer of polydimethylsiloxane, polyethylene oxide and polypropylene oxide [DBP-732 (demetallized in the same manner as poly (alkylene oxide) block copolymer) manufactured by AMAX Co., Ltd.] in 60 mL of ethanol. The mixed solution obtained was added and stirred to obtain a transparent and uniform coating solution.

  A porous film was prepared and modified in the same manner as in Example 1.

  The porous film before the modification retained a periodic 2D-hexagonal structure with an interplanar spacing of 7.0 nm by X-ray diffraction measurement. The relative dielectric constant of this film was k = 4.8. Furthermore, from cross-sectional TEM observation, the pores had a narrow portion with a pore diameter of about 10 mm. The average pore diameter of the porous film was 5.9 nm.

This porous film was modified in the same manner as in Example 1. The relative dielectric constant of the film after modification is k
= 2.3. Further, the modified porous film is put into a vacuum chamber, 10% pentakis (ethylmethylamide) tantalum-containing isopropyl alcohol vapor and NH ₃ gas are introduced into the chamber, and TaN is added at a reaction pressure of 5 Torr and a reaction temperature of 400 ° C. A film was formed on the porous film. From the cross-sectional TEM observation of the porous film after forming the TaN film, no diffusion of TaN was confirmed in the pores.

[Comparative Example 1]
The porous film was modified in the same manner as in Example 2 except that 1,3,5,7-tetramethylcyclotetrasiloxane was changed to hexamethyldisilazane. Table 3 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

[Comparative Example 2]
The porous film was modified in the same manner as in Example 2 except that 1,3,5,7-tetramethylcyclotetrasiloxane was changed to trimethylsilyl chloride. Table 3 shows the measurement results of the relative dielectric constant and elastic modulus of the porous film before and after the modification treatment.

  According to the present invention, a modified porous film excellent in hydrophobicity and mechanical strength that can be used for optical functional materials and electronic functional materials, or excellent in hydrophobicity, prevents barrier metal diffusion when used in semiconductor materials. The modified porous film to be used can be suitably used for an interlayer insulating film as a semiconductor material.

Claims (15)

A porous film mainly having a Si—O bond and having an average pore diameter in the range of 0.5 nm to 10 nm and an organosilicon compound are brought into contact with each other under heating at 100 to 600 ° C. without using a metal catalyst. A method for modifying a film,
As the organosilicon compound,
A Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule may be the same or different. ) And two or more Si—X—Si bond units (X is O, NR, C _f H _2f (f is 1 or 2) or C ₆ H ₄
R represents C _g H _{2g + 1} (g is an integer of 1 to 6) or C ₆ H ₅ . A method for modifying a porous film, which comprises using an organosilicon compound having one or more of The porous film is selected from a porous film (1) having randomly shaped pores, a porous film (2) having a periodic pore structure, or a porous film (3) having a crystal structure of a zeolite structure The method for modifying a porous film according to claim 1, which is any one of the above. The method for modifying a porous film according to claim 1, wherein the porous film and the organosilicon compound are contacted in the presence of H ₂ O. The method for modifying a porous film according to claim 2, wherein the porous film (2) having a periodic pore structure has a 2D-hexagonal structure, a 3D-hexagonal structure, or a cubic structure. Porous film, a multi-porous film that have a narrow portion in the pores, and the with the film organosilicon compound, without using a metal catalyst, is contacted under heating at 100 to 600 ° C. The method for modifying a porous film according to claim 1, wherein at least a part of the narrow portion is closed. Contacting the porous film and the organosilicon compound in the presence of H ₂ O.
The method for modifying a porous film according to claim 5, wherein: The porous film (2) having a periodic pore structure has a diffraction peak having a maximum relative intensity among diffraction peaks measured by an X-ray diffraction method in a range of a surface spacing of 1.3 nm to 13 nm. The method for modifying a porous film according to claim 2 .   The method for modifying a porous film according to claim 1, wherein the organosilicon compound is a cyclic siloxane. The cyclic siloxanes are
Formula (I):

(In the formula, R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF _{3 (CF 2) b (CH} 2) c, shows the _{C d H 2d-1, OC} e H 2e + 1, or a halogen atom, a is an integer of 1-3, b is an integer of 0, c is An integer of 0 to 4, d is an integer of 2 to 4, e is an integer of 1 to 6,
L is an integer of 0 to 8, m is an integer of 0 to 8, n is an integer of 0 to 8, and 3 ≦ L + m + n ≦ 8.
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). )
The method for modifying a porous film according to claim 8 , wherein the method is at least one cyclic siloxane compound represented by the formula: The organosilicon compound is
General formula (II): YSiR ¹⁰ R ¹¹ ZSiR ¹² R ¹³ Y
(Wherein R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same as or different from each other, and H, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) represents _c , OC _e H _{2e + 1} , or a halogen atom,
a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4, e is an integer of 1 to 6,
Z is O, (CH ₂ ) _d , C ₆ H ₄ , (OSiR ^a R ^b ) _n O, OSiR ^c R ^d QSiR ^e R ^f O, or NR ^g , and R ^a , R ^b , R ^c , R ^d , R ^e and R ^f may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , halogen An atom or OSiR ^h R ⁱ R ^j , a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4; d is an integer of 1 to 2; Is an integer of 10, Q represents (CH ₂ ) _m or C ₆ H ₄ , m is an integer of 1 to 6, and R ^h , R ⁱ and R ^j may be the same or different from each other;
Each represents H or CH ₃ , R ^g represents (CH ₂ ) _p or C ₆ H ₄ , p is an integer of 1 to 6;
Two Ys may be the same or different, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (C
F ₂ ) _b (CH ₂ ) _c , OC _e H _{2e + 1} , or a halogen atom, a is an integer of 1 to 3, b is an integer of 0 to 10, c is an integer of 0 to 4, e is 1 An integer of ~ 6,
R ^a or R ^b , R ^c or R ^d , R ^e or R ^f appearing in the formula, at least any two of the two Y are H, OH, OC _e H _{2e + 1} (e is 1 to 6) Integer), or a halogen atom.
)
Method for modifying a porous film according to any one of claims 1 to 6, characterized in that in at least one organic silicon compound represented by. The organosilicon compound is
General formula (III):

(In the formula, R ¹⁵ , R ¹⁶ , R ¹⁸ , R ¹⁹ , R ²¹ and R ²² may be the same as or different from each other, and H, OH, C ₆ H ₅ , C _a H _{2a + 1} , CF ₃ (CF ₂ ) _b (CH ₂ ) _c , OC _e H _{2e + 1} , or a halogen atom, and R ¹⁷ , R ²⁰ , and R ²³ may be the same as or different from each other, and C ₆ H ₅ , Or C _a H _{2a + 1} , a is an integer of 1 to 2, b is an integer of 0 to 10, and c is 0 to
An integer of 4, e is an integer of 1-6,
L is an integer of 0 to 8, m is an integer of 0 to 8, n is an integer of 0 to 8, and 3 ≦ L + m + n ≦ 8.
In the formula, Si—A bond unit (A is H, OH, OC _e H _{2e + 1} (e is an integer of 1 to 6) or a halogen atom, and a plurality of A in the same molecule are the same or different. May be included). )
Method for modifying a porous film according to any one of claims 1 to 6, characterized in that in at least one cyclic silazane compound represented. Porous film that has been modified obtained by the modification method according to any of claims 1 to 11. A semiconductor material comprising the modified porous film according to claim 12 . 14. The semiconductor material according to claim 13 , which is an interlayer insulating film. 15. A semiconductor device comprising the semiconductor material according to claim 13 or 14 .