JP3025091B2 - Organic thin film and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic thin film and a method for forming the same, and more particularly, to an organic thin film having a low surface energy, an adsorption method and a Langmuir-Blodgett method (hereinafter referred to as LB method). And a method for forming an organic thin film using the same.

[0002]

2. Description of the Related Art In recent years, interest in molecular electronics for applying the functionality of organic molecules to electronic devices and the like has been increasing. In particular, applications of low surface energy organic thin films that exhibit unique properties such as water and oil repellency, low friction properties, and chemical resistance to electronic devices are diverse, including liquid crystal alignment films, lubricating films, and water repellent films. Expected.

As a method for obtaining such a low surface energy organic thin film, a method of forming a fluorine group on the thin film surface is generally used. For example, an LB film of a fluorinated carboxylic acid (Thin Solid Films 141 vol.
p. 165-169, 1986), and an organic thin film of a fluorine-containing compound such as a fluorine-containing polyimide LB film (JP-A-02-56274) and a method for forming the same.

On the other hand, as an example of application of a low surface energy organic thin film to an electronic device, an alignment film using a liquid crystalline silane coupling agent to improve the alignment (Japanese Patent Laid-Open No.
186818), an alignment film comprising a mixture of a carrier capable of adsorbing an ionic compound and a polymer compound (Japanese Patent Laid-Open No.
24427) or a magnetic recording medium using a silane coupling agent as a lubricant (JP-A-62-15933).
2), a magnetic recording medium using a silane coupling agent and a lubricant comprising a fluorinated carbon-based compound (JP-A-63-163);
52319) and the like.

[0005]

However, the method of forming fluorine on the surface of a thin film in the above-mentioned conventional example has the following problems. For example, when forming a low surface energy organic thin film by modifying a fluorine group in an organic molecule,
The modification ratio of the fluorine group and the selection range of the organic material are very limited. Further, it is necessary to introduce a special metal ion in order to alleviate the repulsion between fluorine molecules, so that the film forming conditions are very limited, and the versatility is poor.
Furthermore, when a silane coupling agent or a mixture of a silane coupling agent and a polymer compound or a fluorine compound is used, it is necessary to have a functional group to which an organic molecule can be bonded. There is a problem that it is narrowed.

Accordingly, an object of the present invention is to solve the above-mentioned problems, to provide an organic thin film having a novel structure having excellent water and oil repellency, low friction and chemical resistance, and to easily apply a fluorine group to the thin film surface. An object of the present invention is to provide a method for forming an organic thin film that can be brought.

[0007]

According to the present invention, there is provided an adsorption layer comprising an organosilicon compound and a polyimide monomolecular film or a monomolecular cumulative film (hereinafter, referred to as a polyimide film). ), Wherein the organosilicon compound is an organic thin film having a fluoroalkyl group and an alkoxyl group or chlorine, and comprises 1750 to 1650c
An organic thin film having a strong infrared absorption spectrum at m ^-1 and 1300 to 1100 cm ^-1 .

The present invention also includes an organic thin film in which the fluoroalkyl group is a straight chain having 10 to 20 carbon atoms and the alkoxyl group is an ethoxy or methoxy group.

Further, the present invention provides an adsorption layer formed by vapor-phase growth of an organosilicon compound having a fluoroalkyl group and an alkoxyl group or chlorine on a substrate, and then forms a monomolecular film of an amine polyamidate on the adsorption layer. Or LB for monomolecular accumulation film
This is a method for forming an organic thin film, characterized in that a polyimide film is obtained by heating and baking an organic thin film formed by a method.

[0010] The present invention is also a method for forming an organic thin film having a substrate surface made of an amorphous inorganic oxide, silicon or gold.

The present invention also provides a monomolecular film or a monomolecular cumulative film of a polyamic acid amine salt formed on a substrate by an LB method.
Next, the organic thin film obtained by vapor-phase growing an organosilicon compound having a fluoroalkyl group and an alkoxyl group or chlorine on the monomolecular film or the monomolecular cumulative film to form an adsorption layer is heated and fired to form a polyimide film. And a method for forming an organic thin film.

Further, according to the present invention, after a monomolecular film or a monomolecular cumulative film of an amine polyamic acid salt is formed on a substrate by an LB method, the monomolecular film or the monomolecular cumulative film is heated and fired to form a polyimide film. Then, an organic silicon compound having a fluoroalkyl group and an alkoxyl group or chlorine is vapor-phase grown on the polyimide film to obtain an adsorption layer.

Further, according to the present invention, after forming a monomolecular film or a monomolecular cumulative film of an amine polyamic acid salt on a substrate by an LB method, the monomolecular film or the monomolecular cumulative film is heated and fired to form a polyimide film. Then, the organic thin film obtained by vapor-phase growing an organosilicon compound having a fluoroalkyl group and an alkoxyl group or chlorine on the polyimide film to form an adsorption layer is further heated. It is a forming method.

Further, the present invention is a method for forming an organic thin film wherein the fluoroalkyl group is a straight-chain having 10 to 20 carbon atoms and the alkoxyl group is a methoxy or ethoxy group.

Hereinafter, the present invention will be described in detail.

FIG. 1 shows a typical example of the layer structure of the organic thin film of the present invention.
4 to FIG.

The organic thin film 10 shown in FIG. 1 has a form in which an adsorption layer 2 of an organosilicon compound and a polyimide film 3 are sequentially laminated on a substrate 1.

The organic thin film 10 shown in FIG. 2 has a structure in which a chromium thin film 5 and a gold thin film 6 are sequentially stacked on a substrate 4, and an organic silicon compound adsorption layer 2 and a polyimide film 3 are sequentially stacked.

The organic thin film 10 shown in FIG. 3 has a form in which a polyimide film 3 and an organic silicon compound adsorption layer 2 are sequentially laminated on a substrate 1.

The organic thin film 10 shown in FIG. 4 is formed by depositing gold on a substrate 4, forming a gold thin film 6, and then sequentially stacking an organic silicon compound adsorption layer 2 and a polyimide film 3. In the present invention, the thickness of the adsorption layer is preferably 15 to 300 mm, and the thickness of the polyimide film is preferably 4 to 50 mm.

The substrate used in the present invention is not particularly limited in size, shape, material, etc., but the surface of the substrate for forming the organosilicon compound adsorption layer may be made of amorphous inorganic oxide, silicon, or the like. Alternatively, gold is preferable in order to strengthen the bond with the organosilicon compound.

The organosilicon compound used in the present invention may have at least one fluoroalkyl group and at least one alkoxyl group or chlorine.

In order to exhibit the specific properties of the fluorine group, the fluoroalkyl group is preferably a straight chain having 10 to 20 carbon atoms. The fluoroalkyl group is obtained by substituting a part or all of the hydrogen atoms of the alkyl group with a fluorine group.

The alkoxyl group is preferably a methoxy or ethoxy group. The organosilicon compound may contain at least one alkoxyl group or chlorine, but when it contains a plurality of alkoxyl groups or chlorine, the bond between the adsorption layer and the substrate or the polyimide film becomes stronger, and It can be expected that organosilicon compounds will be combined.

Further, functional groups other than those described above may be contained in the organosilicon compound, but such functional groups are preferably three-dimensionally smaller than fluoroalkyl groups. And the like.

On the other hand, in the present invention, the polyimide film is LB
The formation by a method is preferable from the viewpoint of forming a thin film. In order to form a polyimide film, which is a polymer material, by a LB method, first, a polyamic acid is mixed with a long-chain alkylamine to impart appropriate hydrophobicity, and then formed into a polyamic acid amine salt. Thereafter, the polyimide film is heated and baked to perform a dehydration cyclization (imidization) reaction and a deamination reaction to form a polyimide film. The polyamic acid can be obtained by subjecting a carboxylic anhydride and a diamine to a condensation reaction. Examples of the carboxylic anhydride include pyromellitic anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic anhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic anhydride, 2-bis (3,4-
Dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropanoic anhydride.

As the diamine, phenylenediamine,
4,4′-oxydianiline, 4,4′-dioxyphenylenedianiline, 4,4′-phenylenedianiline,
4,4'-tidioaniline, 4,4'-sulfonyldianiline, 4,4'-methylenedianiline, 2,2-bis (4-aminophenyl) -1,1,1,3,3,3-
Hexafluoropropane, 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane and the like can be mentioned.

Since the polyamic acid used in the present invention may contain one part of the above structural unit in the polymer main chain, it is necessary to use two or more carboxylic anhydrides and / or two or more diamines. The use of polymeric polyamic acids is also possible.

The long-chain alkylamines have 7 to 7 carbon atoms.
30, preferably 16 to 22 primary to tertiary alkylamines can be used. Further, those in which part or all of the alkyl group is substituted with halogen, those in which one part of the alkyl group is substituted with a hydroxyl group, those having a cyclic structure such as a branched alkyl group or a benzene ring, and the like. It can be used.

The mixing ratio of the polyamic acid to the long-chain alkylamine is preferably such that all the carboxyl groups of the polyamic acid are aminated. That is, there are usually two carboxyl groups per repeating unit of polyamic acid. In this case, the total of repeating units of polyamic acid: the number of moles of primary alkylamine = 1: 1 to 1:
3, more preferably 1: 2 to 1: 2.5.

The solvent used at this time is N, N
-Any solvent capable of sufficiently dissolving the polyamic acid and the alkylamine and developing the solution on the water surface, such as dimethylacetamide (DMAC; hereinafter, referred to as DMAC). Or a mixed solvent. The concentration at this time is not particularly limited, but is preferably in the range of 1 × 10 ⁻⁵ to 1 × 10 ⁻³ repeating unit / l from the viewpoint of expandability.

In general, there is an infrared absorption spectrum as one method for knowing the surface structure of an organic thin film. FIG. 5 shows an example of an infrared absorption spectrum of the organic thin film of the present invention. As will be described later in detail, as shown in FIG. 5, the organic thin film of the present invention has 1750-1650 cm ^-1 and 1300-1100 cm ^-1 .
It has a strong infrared absorption spectrum at cm ^-1 . Further, the absorption intensity at 1750-1650 cm ^-1 is 1300-
Greater than the absorption intensity of 1100 cm ^-1 , the former being -CF
_2- , the latter is thought to be due to the carbonyl group.
Further, since -CF ₂ -is derived from an organosilicon compound and a carbonyl group is derived from a polyimide film, the organic thin film of the present invention may be an organic thin film comprising a reaction product of the above organosilicon compound and the above polyimide film. I understand. Further, -CF ₂ - since the absorption intensity of the absorption spectrum due to larger than that of a carbonyl group, reduction of the surface energy may be due to the effect of the fluorine groups.

In the method of the present invention, first, the organosilicon compound is vapor-phase-grown on the substrate surface to form an adsorption layer in which physicochemical adsorption is performed. Subsequently, a low molecular weight organic thin film can be formed by forming a monomolecular film of a polyamic acid amine salt or a monomolecular cumulative film on the adsorption layer by the LB method, followed by heating and baking. Note that a monomolecular film or a monomolecular cumulative film formed by the LB method is called an LB film.

Although the detailed mechanism of obtaining a low surface energy organic thin film by the above-mentioned forming method is not clear, the organic silicon can be simultaneously obtained by dehydration cyclization (imidization) and deamination of the polyamic acid amine salt by heating and baking. It is considered that interdiffusion between the compound and the LB film occurs, and the fluorine groups are arranged on the outermost surface of the thin film, so that the surface energy is reduced.

As a second method of the present invention, an LB film of a polyamic acid amine salt is formed on a substrate, and then, an adsorption layer of the organosilicon compound is formed on the LB film. There is a method of obtaining an energy organic thin film. According to this method, the organosilicon compound is physicochemically adsorbed on the LB film of the polyamic acid amine salt, and subsequently heated and calcined, and the organic dehydration cyclization (imidization) and deamination reaction of the polyamic acid amine salt are simultaneously performed. It is considered that the bond between the silicon compound and the polyimide film becomes stronger, and the surface energy is reduced by the fluorine groups arranged on the outermost surface.

As a third method of the present invention, a polyimide film is formed by forming an LB film of a polyamic acid amine salt on a substrate and then heating and baking to form an adsorption layer of an organosilicon compound on the polyimide LB film. Then, there is a method of obtaining a low surface energy organic thin film. Also in this method, it is considered that the surface energy is reduced by the fluorine groups of the organosilicon compound covering the outermost surface of the organic thin film.

As a fourth method of the present invention, there is a method in which the organic thin film formed by the above third method is further heated and fired. According to this method, the bond between the polyimide LB film and the organosilicon compound becomes stronger. Further, the surface smoothness is improved by making the surface of the organic thin film uniform.

As a method of forming an organosilicon compound on a substrate, there are generally a vapor phase growth method, a dipping method, a coating method, and the like. The growth method is preferred.

In the present invention, the aforementioned polyamic acid amine salt solution is gently spread on the water surface to form an LB film. At this time, pure water at 2 to 25 ° C. is used as the aqueous phase. preferable. In the present invention, the pH may be adjusted by adding various metal ions, acids or alkalis to the pure water. Subsequently, the polyamic acid amine salt mixed solvent is compressed on the water surface to form a monomolecular film of the polyamic acid amine salt on the water surface.

While maintaining the surface pressure of the monomolecular film constant, the substrate is immersed in a direction crossing the monomolecular film on the water surface, and then continuously pulled up to accumulate two layers of the Y-type monomolecular cumulative film on the substrate. can do.

At this time, the surface pressure of the monomolecular film depends on the kind of the polyamic acid or the amine, but is approximately 5 to 35 mN.
/ M is preferable.

[0042]

EXAMPLES The present invention will be described more specifically with reference to the following examples.

Example 1 An organic thin film 10 having the structure shown in FIG. 1 was prepared as follows.

First, the cleaned Si substrate 1 is placed on CF ₃ (C
It was kept in a vapor of F ₂ ) ₇ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ at room temperature for 24 hours to form an adsorption layer 2. Next, a polyamic acid represented by the formula 1,

[0045]

Embedded image Was dissolved in DMAC to prepare a polyamic acid solution having a monomer conversion concentration of 1 × 10 ⁻³ mol.

Next, 1 × 10 ^-3 mol of a DMAC solution of N, N-dimethyloctadecylamine was prepared and mixed with the polyamic acid solution at a volume ratio of 2: 1 to prepare a polyamic acid amine salt solution.

The above polyamic acid amine salt solution was cooled to a water temperature of 20.
The solution was developed on an aqueous phase composed of pure water at a temperature of ° C. to form a monomolecular film on the surface of the aqueous phase. After removing the solvent by evaporation, the surface pressure is 25 mN / m
Up to. Subsequently, while maintaining the surface pressure constant, the substrate on which the above-mentioned adsorption layer is formed is moved at a speed of 5 in a direction crossing the water surface.
After immersion gently at a speed of 5 mm / min,
The film was gently pulled up with n to form a two-layer Y-type monomolecular accumulation film (LB film) on the adsorption layer 2.

Subsequently, the substrate was heated and baked at 300 ° C. for 10 minutes to obtain a polyimide film 3. As a result of measuring the film thickness of the polyimide film by an ellipsometry method, 4
Was Å.

Further, droplets having various surface tensions before and after heating and firing were measured, and the critical surface tension was measured.
N / m was reduced to 7 mN / m. When the obtained organic thin film was immersed in ethanol and the critical surface tension was measured again, there was no change from that before immersion in ethanol.

Example 2 An organic thin film 10 having the structure shown in FIG. 2 was prepared as follows.

The Corning # 7059 glass substrate 4 was washed, and Cr was deposited as a subbing layer on the substrate by a vacuum deposition method at a deposition rate of 5 ° / sec, an ultimate pressure of 2 × 10 ⁻⁶ Torr,
A chromium thin film 5 was obtained under the condition of a film thickness of 50 °. Further, Au was formed on the chromium thin film 5 under the conditions of a deposition rate of 10 ° / sec, an ultimate pressure of 2 × 10 ⁻⁶ Torr, and a film thickness of 2000 °, to obtain a gold thin film 6.

Subsequently, an adsorption layer 2 and an LB film of a polyamic acid amine salt were formed on the gold thin film 6 in the same manner as in Example 1, and baked by heating to obtain a polyimide film 3.

Further, when the critical surface tension was measured and immersed in ethanol in the same manner as in Example 1, the critical surface tension of the organic thin film 10 was found to be 6 mN / m, and the critical surface tension before and after immersion in ethanol. There was no change.

Example 3 An organic thin film 10 having the structure shown in FIG. 3 was prepared as follows.

The cleaned Si substrate 1 was subjected to a hydrophobic treatment, and a 12-layer amine polyamidate LB film was formed in the same manner as in Example 1.

Subsequently, the substrate is made of CF ₃ (CF ₂ ) ₇ CH ₂ C
H ₂ Si (OC ₂ H ₅ ) ₃ vapor at room temperature for 24 hours,
The adsorption layer 2 was formed.

Subsequently, the resultant was baked at 300 ° C. for 10 minutes to form a polyimide film 3.

Further, when the critical surface tension was measured and immersed in ethanol in the same manner as in Example 1, the critical surface tension of the organic thin film 10 was found to be 6 mN / m, and the critical surface tension before and after immersion in ethanol. Did not change.

Example 4 An organic thin film 10 having the structure shown in FIG. 4 was prepared as follows.

A gold thin film 6 was formed on a glass substrate 4 in the same manner as in Example 2. Subsequently, the adsorption layer 2 was formed on the gold thin film 6 in the same manner as in Example 1.

Subsequently, a polyamic acid represented by the formula (2):

[0062]

Embedded image A DMAC solution (concentration in terms of monomer: 1 × 10 ⁻³ mol),
A solution of an amine polyamidate was prepared by mixing a DMAC solution of N, N-dimethyloctadecylamine (concentration in terms of monomer: 1 × 10 ⁻³ mol) at a volume ratio of 1: 2.

From this solution, six layers of polyamic acid amine LB films were formed in the same manner as in Example 1.

Subsequently, the substrate was heated and baked at 300 ° C. for 10 minutes to obtain a polyimide film 3.

The organic thin film 10 formed through the above steps
On the other hand, when the measurement of the critical surface tension and the immersion in ethanol were performed in the same manner as in Example 1, there was no change in the critical surface tension.

FIG. 5 shows the results of measuring infrared absorption spectra before and after immersion in ethanol. In FIG. 5, 51
Indicates an infrared absorption spectrum before immersion in ethanol, and 52 indicates an infrared absorption spectrum after immersion in ethanol. As can be seen from FIG. 5, there is no change in the absorption spectrum before and after the immersion in ethanol, and the carbonyl group at 1750 cm ⁻¹ and 1210 c
-CF ₂ to m ^-1 -, alkoxyl group 1150 cm ^-1 and 960 cm ^-1, an absorption spectrum is attributed to siloxane bond 1100 cm ^-1.

Example 5 An organic thin film 10 having the structure shown in FIG. 3 was prepared as follows.

First, a solution prepared by dissolving a polyamic acid represented by the formula 3 and N, N-dimethyloctadecylamine at a monomer conversion concentration of 1 × 10 ^-3 mol with DMAC at a ratio of 1: 2 was mixed. An amine salt solution was prepared.

[0069]

Embedded image From this solution, 12 layers of polyamic acid amine salt LB films were formed on the cleaned Si substrate 1 in the same manner as in Example 1.

Subsequently, this was heated and baked at 300 ° C. for 10 minutes to form a polyimide film 3, and then CF ₃ (CF ₂ ) ₇
It was kept in a vapor of CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ at room temperature for 24 hours to form an adsorption layer 2.

The organic thin film 10 formed through the above steps
Was prepared in the same manner as in Example 1.
N / m.

Example 6 The organic thin film 10 formed in Example 5 was further heated and baked at 300 ° C. for 10 minutes, and the critical surface tension was measured in the same manner as in Example 1. The result was 7 mN / m. Furthermore, when the surfaces of this organic thin film and the organic thin film prepared in Example 5 were observed with a scanning electron microscope (SEM), the organic thin film of this example was more excellent in surface smoothness.

Example 7 An organic thin film 10 having the structure shown in FIG. 1 was prepared as follows.

The cleaned Si substrate 1 is made of CF ₃ (CF ₂ ) ₇ C
After holding in an H ₂ CH ₂ SiCl ₃ vapor for 1 hour at room temperature to form the adsorption layer 2, six layers of polyamic acid amine LB films were formed in the same manner as in Example 1.

Subsequently, the organic thin film was heated and baked at 300 ° C. for 10 minutes to obtain a polyimide film 3. With respect to the organic thin film 10 formed through the above steps, measurement of critical surface tension and immersion in ethanol were performed in the same manner as in Example 1. As a result, the critical surface tension was 6 mN / m, and there was no change before and after immersion in ethanol.

Example 8 An organosilicon compound was prepared using CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ Si (C
H ₃₎ except for changing the ₂ Cl was prepared an organic thin film 10 having the structure shown in FIG. 1 in the same manner as in Example 7.

The measurement of the critical surface tension and the immersion in ethanol were performed on the organic thin film 10 in the same manner as in Example 1. As a result, the critical surface tension was 8 mN / m, and there was no change before and after immersion in ethanol.

Comparative Example 1 An organic thin film 60 having the structure shown in FIG. 6 was prepared as follows.

Except that the organosilicon compound adsorption layer was not formed, six layers of the polyimide monomolecular cumulative film 62 were formed on the Si substrate 61 in the same manner as in Example 1.

Further, similar to the first embodiment, the organic thin film 60
Was 38 mN / m. From this result, it was found that the surface energy was not reduced even when heated and baked without the adsorbed layer of the organosilicon compound in the present invention.

[0081]

According to the present invention, an adsorption layer of an organosilicon compound having at least one fluoroalkyl group and at least an alkoxyl group or chlorine and a polyimide monomolecular film or a monomolecular cumulative film are formed by an adsorption method and an LB method. By forming it, a low surface energy organic thin film excellent in heat resistance and chemical resistance can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing one example of a layer structure of an organic thin film of the present invention.

FIG. 2 is a conceptual diagram showing another example of the layer structure of the organic thin film of the present invention.

FIG. 3 is a conceptual diagram showing another example of the layer structure of the organic thin film of the present invention.

FIG. 4 is a conceptual diagram showing another example of the layer structure of the organic thin film of the present invention.

FIG. 5 is a chart showing an example of an infrared absorption spectrum of the organic thin film of the present invention.

FIG. 6 is a conceptual diagram showing a layer structure of an organic thin film formed in a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Si substrate 2 Adsorption layer 3 Polyimide film 4 Glass substrate 5 Chromium thin film 6 Gold thin film 10 Organic thin film 51 Infrared absorption spectrum before ethanol immersion 52 Infrared absorption spectrum after ethanol immersion 60 Organic thin film 61 Si substrate 62 Polyimide film

Continuation of the front page (56) References JP-A-3-121129 (JP, A) JP-A-62-135530 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1 / 00-35/00 B01J 19/00 B05D 1/20

Claims (10)

(57) [Claims] 1. An adsorption layer comprising an organosilicon compound and a polyimide monomolecular film or a monomolecular accumulation film formed on a substrate, wherein the organosilicon compound has a fluoroalkyl group and an alkoxyl group or chlorine. , 1750-1650
The organic thin film characterized by exhibiting a strong infrared absorption spectrum cm ^-1 and 1300~1100cm ^-1. 2. A fluoroalkyl group having 10 to 20 carbon atoms.
The organic thin film according to claim 1, wherein the organic thin film is linear. 3. The organic thin film according to claim 1, wherein the alkoxyl group is a methoxy or ethoxy group. 4. An adsorption layer is formed by vapor-phase growth of an organosilicon compound having a fluoroalkyl group and an alkoxyl group or chlorine on a substrate to form an adsorption layer, and then a monomolecular film or monomolecule of an amine polyamidate is formed on the adsorption layer. Langmuir accumulation film
A method for forming an organic thin film, comprising heating and firing an organic thin film formed by a blow jet method to obtain a polyimide monomolecular film or a monomolecular cumulative film. 5. The method according to claim 4, wherein the surface of the substrate is made of an amorphous inorganic oxide, silicon or gold. 6. A monomolecular film or a monomolecular accumulation film of a polyamic acid amine salt is formed on a substrate by a Langmuir-Blodgett method, and then a fluoroalkyl group and an alkoxyl film are formed on the monomolecular film or the monomolecular accumulation film. A method for forming an organic thin film, characterized in that an organic thin film obtained by forming an adsorption layer by vapor-phase growth of an organosilicon compound having a base or chlorine is heated and baked to obtain a polyimide monomolecular film or a monomolecular cumulative film. . 7. A monomolecular film of a polyamic acid amine salt is formed on a substrate by a Langmuir-Blodgett method, and then the monomolecular film or the monomolecular cumulative film is heated and fired to form a polyimide monomolecular film. Or to form a monomolecular cumulative film,
Then, an organic silicon compound having a fluoroalkyl group, an alkoxyl group, or chlorine is vapor-phase grown on the polyimide monomolecular film or monomolecular accumulation film to obtain an adsorption layer. 8. A monomolecular film or a monomolecular accumulation film of a polyamic acid amine salt is formed on a substrate by a Langmuir-Blodgett method, and the monomolecular film or the monomolecular accumulation film is heated and fired to form a polyimide monomolecular film. Forming a film or a monomolecular cumulative film, and then forming an adsorption layer by vapor-phase growing an organosilicon compound having a fluoroalkyl group and an alkoxyl group or chlorine on the polyimide monomolecular film or the monomolecular cumulative film; A method for forming an organic thin film, further comprising heating and firing the obtained organic thin film. 9. The fluoroalkyl group has 10 to 20 carbon atoms.
The method for forming an organic thin film according to any one of claims 4 to 8, wherein the organic thin film is linear. 10. The method for forming an organic thin film according to claim 4, wherein the alkoxyl group is a methoxy or ethoxy group.