JPH02266930A - Electric element - Google Patents

Abstract

PURPOSE:To obtain an electric element excellent in mechanical, chemical and thermal durability and having molecular orientation properties by applying a solution of a specific fumaric diester polymer to a substrate by a spin coat method to form a polymer insulating layer. CONSTITUTION:This electric element has a substrate, a polymer insulating layer having a thickness of 50-1000Angstrom formed on the substrate by applying a solution of a fumaric diester polymer to said substrate by a spin coat method and an electrode. This fumaric diester polymer contains a repeating unit of fumaric diester represented by formula (I) (wherein at least one of R1 and R2 is a 3-12C branched alkyl group, a 3-12 cycloalkyl group, a 2-6C substituted alkyl group having a substitutent of a 3-14 ring structure, a 3-100C substituted cycloalkyl group having a substituent of a ring structure or a siloxane type hydrocarbon group).

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a spin coated film on a substrate with a thickness of 50 to 1
The present invention relates to an electrical device having a smooth and homogeneous polymer insulation layer of 1,000,000.

<Prior art> Varistors, thyristors, diodes, photodiodes, light emitting diodes, transistors, and LSIs that integrate them are basically MIM (Metal/In5
ulator/Metal: metal/insulator/metal).

M I S (Metal/In5ulator/Sa
s+1 conductor: metal/insulator 7 semiconductor)
, M S (Metal/Sem1cor+duc
tor: metal 7 semiconductor rich Schottky element), SIS (Sem1conductor/In5ulat
or/Sem1conductor). Among these, for MIM, MIS, and SIS cables that require an insulating layer (hereinafter abbreviated as "layer"), the surface of a substrate made of aluminum or beryllium or a silicon substrate is usually thinly oxidized to provide metal oxide and/or SiO□ insulation. Methods are available in which a layer is formed and then a counter electrode is provided. However, this method cannot be applied to metals and/or semiconductor substrates other than those mentioned above, and in particular when using semiconductors other than Si, including chemical compound semiconductors, this method is suitable for applications such as diodes, photodiodes, light emitting diodes, field effect transistors, etc. It has the disadvantage that it cannot be applied to MIS type elements with a wide sm. Therefore, if the organic compound I@edge thin film cage can be used in one layer, all combinations are possible.

In this case, the insulating thin film used is required to have a thickness of 50 to 1000 layers, and to be smooth and homogeneous.

By the way, one of the methods for creating ultra-thin polymer films that are smooth and homogeneous with uniform molecular orientation is the Langmuir-Prodgett method (
(hereinafter abbreviated as LB method) is known.

In the LB method, organic molecules are diluted with an organic solvent and 2
Next, it is spread on a clean water surface, and the gas film that remains after the solvent evaporates is compressed in the plane direction to form a solid film with densely backed molecules, and then the solid film is transferred to the surface of the solid substrate. The thin film formed on the substrate is called an LB film [(for example, in the literature, B.

Blodgett, J., Am., Chem., Soe, 5
5, 1007 (1935)), Trap, Fukuda
et al., J. Co11oid Interface Sci.
, 54, 430 (1976)], the features of the LB film are 1.
It is possible to create anything from ultra-thin films on the order of molecules to cumulative films of arbitrary thickness by repeating lamination, and the film is smooth and homogeneous with uniform molecular orientation. Therefore, LB film is expected to be used as a material for various electronics, and has 1 carbon number.
LB film formation of straight chain fatty acids of 6 or more or their alkaline earth metal salts and cadmium salts has been widely studied [for example, Kiyonari Fukuda and Hiroo Nakahara, Kagaku Sou A40 <Molecular Assembly>
p, 112-104. t983], However, the LB film of M et al.'s fatty acid or its metal salt has a drawback in that it is poor in mechanical strength, heat resistance, etc., and is therefore impractical. Therefore, a method has been devised in which polymerizable fatty acids are formed into an LB film and then subjected to polymerization treatment, or where polymerizable fatty acids are polymerized on the water surface and then formed into an LB film. The formation is severe and transfer to the substrate is extremely difficult.

On the other hand, one possible method is to prepare an LB film using a polymer and accumulate it on the substrate.

General polymers have a thread-like aggregated state even in a dilute solution, and do not form a gas film when expanded on the water surface, making it difficult to form an LB film.9 Exceptionally, polypeptides and It has been reported that by using polyfumarate, the polymer chains form a rod-like structure and form an LB film [J, H, Mc
alear et al., Symposium VLSI T
achnology, DigeStoftech,
Papar, 82 (1981L K, Shigeha
ra et al., J. Muhoer, ches+, soc.

1237 Vol, 109. (19g?)].

Furthermore, attempts have been made to spin-coat a synthetic polymer solution onto a substrate in order to provide an insulating layer on an electric element, but the performance required for an ultra-thin film requires a heat resistance temperature of at least 200°C. .

It must be thermally and chemically stable, with excellent moisture resistance, and mechanical and electrical properties.There are only a limited number of polymers that meet these requirements1, such as polyimide, polyethersulfone, and polyphenylene. sulfide, polysulfone,
Polyphenylene oxide, polyethylene terephthalate, etc. are known. In the method of manufacturing ultra-thin films by spin coating, the polymer is dissolved in an organic solvent to create a dilute solution, and after spin coating, the solvent is evaporated to form an insulating film. For example, dimethyl, which dissolves polyimide and polysulfone, Solvents such as acetamide and N-methylpyrrolidone are polar solvents and have high boiling points, so they have the disadvantage that they have a slow evaporation rate and are likely to remain in ultra-thin films. Furthermore, the viscosity of the polymer solution is relatively high, and the reality is that considerable skill is required to create a uniform and smooth film in an electrical element.

<Problems to be Solved by the Invention> An object of the present invention is to provide an electrical element including a polymer insulating layer that is excellent in mechanical, chemical and thermal durability and has molecular orientation.

<Means for Solving the Problems> According to the present invention, a substrate, a polymeric insulating layer having a thickness of 5 to 1000 layers formed by forming a solution of a fumaric acid diester polymer on the substrate by a spin coating method; , an electrode, wherein the fumaric acid diester polymer has the following general formula (wherein R8 and R1 represent the same or specific groups, and at least one of R2 and R1 has a carbon number of A branched alkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a substituted alkyl group having 2 to 6 carbon atoms having a substituent having a ring structure having 3 to 14 carbon atoms, and a substituent having the above ring structure. represents a substituted cycloalkyl group or siloxane hydrocarbon group having 3 to 10 carbon atoms, and the branched alkyl group, the cycloalkyl group, the substituted alkyl group, the substituted cycloalkyl group, and the siloxane hydrocarbon group An electric element is provided, characterized in that it contains a repeating unit of a fumaric acid diester represented by ), which may contain a hetero atom and may be substituted with a halogen atom.

The present invention will be explained in more detail below.

In the present invention, an electric element is, for example, an MIM structure of ``metal/polymer insulating layer/metal'', ``metal/polymer insulating layer 7
It has an MIS structure of "semiconductor" and a "S/S structure of semiconductor/polymer insulating layer/semiconductor", and one of the metal and semiconductor represents the substrate, and the other represents the electrode.

In the present invention, a fumaric acid diester polymer containing repeating units of a fumaric diester represented by the following general formula is used as a component for constructing a polymer insulating layer. In the formula 0, R3 and R3 are the same or different groups. , and at least one of R1 and R8 is a branched 9-alkyl group having 3 to 12 carbon atoms, and 3 to 12 carbon atoms.
~12 cycloalkyl group, a substituted alkyl group having 2 to 6 carbon atoms having a substituent having a ring structure having 3 to 14 carbon atoms, a substituted cycloalkyl group having 3 to 10 carbon atoms having a substituent having the above ring structure, or siloxane Yarn hydrocarbon table representation.

The branched alkyl group, the cycloalkyl group, the substituted alkyl group, the substituted cycloalkyl group and the siloxane hydrocarbon group contain a heteroatom such as a nitrogen atom, an oxygen atom, a phosphorus atom, a sulfur atom, etc. When only one of Rl and R8, which may be substituted with a halogen atom, is the above-mentioned hydrocarbon group, the other group is an alkyl group having 1 to 12 carbon atoms, or a cyclocarbon group having 3 to 12 carbon atoms. The fumaric acid diester polymer having a repeating unit represented by the above general formula is preferably an alkyl group.

For example, diethyl fumarate, diisopropyl fumarate, di-5ao-butyl fumarate, di-tart-butyl fumarate, isopropyl-n-amyl fumarate, tart-butyl-5ao-butyl fumarate, te
rt-butylisoamyl fumarate, isopropyl-t
Dialkyl fumarates such as ert-butyl fumarate;
Dicyclopentyl fumarate, dicyclohexyl fumarate.

Dicycloalkyl fumarates such as dicyclohebutyl fumarate and cyclopentyl-cyclohexyl fumarate;
Alkylcycloalkyl fumarates such as isopropyl-cyclohexyl fumarate; diaryl fumarates such as diphenyl fumarate and dibenzyl fumarate; alkylaryl fumarates such as isopropyl-phenyl fumarate and tart-butylbenzyl fumarate; ditrimethylsilyl fumarate , isopropyl-tris(trimethylsiloxy)silylpropyl fumarate, tert
Various alkylsiloxanyl fumarates such as -butyl-tris(trimethylsiloxy)silylpropyl fumarate; arylsiloxanyl fumarates such as cycloalkylsiloxanyl fumarate; ditrifluoroethyl fumarate.

Various fluoroalkyl fumarates such as dihexafluoroisopropyl fumarate, ciba-fluorobutylethyl fumarate, diperfluorooctylethyl fumarate; isopropyl-hexafluoroisopropyl fumarate, isopropyl-perfluorooctylethyl fumarate, tert -Alkylfluoroalkyl fumarates such as butyl-perfluorooctylethyl fumarate; homopolymers or copolymers such as arylfluoroalkyl fumarate and bischloroisopropyl fumarate; further comprising the fumaric acid diester polymers; fumaric acid diester, styrene, α-methylstyrene,
Examples include copolymers with known radically polymerizable heptamers such as vinyl acetate, vinyl benzoate, vinylpyridine, vinyl ethers, acrylonitrile, and (meth)acrylic acid esters.

In the present invention, the molecular weight of the fumaric acid diester polymer is 10,000 to 1,000,000, particularly 20,000 in view of the mechanical strength and chemical stability of the polymeric insulating layer.
It is preferably in the range of ~5oooooo.

Further, the polymer insulating layer used in the electric element of the present invention has a film thickness of 5
It needs to be between 0 and 1000 people.

In the present invention, to produce the fumaric acid diester polymer which is a component of the polymeric insulating layer, 1. An ordinary radical polymerization method can be preferably used. 0. The polymerization initiator used in the polymerization has a half-life of 10 hours. temperature is 120
℃ or less and one or more types of azo compounds can be preferably used, and examples of the polymerization initiator include benzoyl peroxide, diisopropyl peroxycarbonate, and tart-butylperoxy-2-ethylhexanoate. % tert-butylperoxypiparate,
The amount of the polymerization initiator, which may include t/rt-butyl peroxydiisobutyrate, sensitized lauroyl, azobisisobutyronitrile, etc., is preferably 10 parts by weight or less per 100 parts by weight of the raw material. More preferably, it is 5 parts by weight or less.

The fumaric acid diester polymer used in the present invention preferably contains at least 60 mol% or more of repeating units of the fumaric acid diester represented by the above general formula, and the glass transition temperature (
Tg) is preferably 200°C or higher.

In the present invention, in order to use the fumaric acid diester polymer as a polymeric insulating layer, the fumaric acid diester polymer is first dissolved in a general-purpose organic solvent such as chloroform, ethylene difluoride, dioxane, tetrahydrofuran, benzene, etc. However, if a solution of fumaric acid diester polymer is prepared, for example, if a high concentration solution or a solution of a high boiling point solvent is used, it will not be possible to control the surface smoothness, homogeneity, etc. when forming a polymer insulating layer. Therefore, it is preferable to use the above-mentioned organic solvent, and chloroform is particularly preferable, and the solution concentration of the fumaric acid diester polymer is 0.0. It is preferable to prepare a solution containing 5 to 20 .mu./-, particularly preferably 0.5 to 10 .mu./-1, and even more preferably 0.5 to 3 .mu./-.

A solution of fumaric acid diester polymer can be obtained at 0
Next, a polymer insulating layer is formed by a solution spin coating method using the fumaric acid diester polymer. Here, the spin coating method is a process in which a solution is dropped onto a rotating substrate to produce a thin film. This is a method in which the film thickness is controlled by the concentration of the m-liquid, the rotational speed of the substrate, the boiling point of the solvent, etc.

In the present invention, the solution of the fumaric acid diester polymer is spin-coated to form an ultra-thin film with a thickness of 50 to 1000, and the rotational speed of the spin coater is set to 1000 to 150.
It is preferable to set the film thickness to about 0.00, and the film thickness varies slightly depending on the working temperature, but under each of the above conditions, it is usually about 1.00.
A desired polymeric insulating layer can be manufactured by spin coating at an operating temperature of about 0 to 36°C.

In the present invention, the substrate used in the pin coating method is
Although it may affect the homogeneity and smoothness of the polymer insulating layer, it is usually visible to the naked eye. l! It is sufficient to have a mirror surface that shows no polishing traces when inspected. Examples of the substrate include A1, Si, Gem, Ni%Fa,
Go, Cu, Pt, Au, rare earth metals, metal oxides and metal oxide semiconductors 1 e.g. S i O,, Ni0
1SnO,, In, O,, indium tin neta glass,
Tin oxide NESA glass (hereinafter abbreviated as NESA), compound semiconductors such as gallium arsenide, gallium phosphide, indium phosphide, chalcogens, transition metal selenides such as zinc selenide and zinc sulfide, sulfides, W03-based chalcogenides, vO□-based Substrates prepared from chalcogenide, polycarbonate, polyethylene terephthalate, polyethylene, polypropylene, etc. can be used, but are not necessarily limited to these, and any conductive or semiconducting material may be used.

In the present invention, an electrode of a conductive material or a semiconductor similar to that of the substrate is formed on a polymer insulating layer having a substrate obtained by the spin coating method using, for example, a vacuum state, high frequency sputtering, ion beam sputtering, molecular beam epitaxy, etc. By installing using this method, the desired electric element can be obtained.

<Effects of the Invention> The electric element of the present invention uses a polymeric insulating layer containing a fumaric acid diester polymer having excellent mechanical strength, heat resistance, weather resistance, transparency, insulation properties, physical properties, etc. It is applicable to electric elements using substrates of all materials such as , metals, and semiconductors, and can be used in primary fields.

(1) M I M (Metal/In5ulato
r/Metal) type elements, i.e. varistors, thyristors, etc.

(2) M I S (Metal/In5ulato
r/Sem1conductor) type elements, i.e. diodes, photodiodes, light emitting diodes (LEDs)
)Such.

(3) SIS (p-5emicond
uctor/In5ulator/n-5amicon
DUCN-5A type devices, ie, diodes, photodiodes, light emitting diodes (LEDs), etc.

<Examples> The present invention will be explained in more detail below using Examples and Reference Examples, but the present invention is not limited thereto.

1L diisopropyl fumarate in a glass ampoule 10.
and 0.1% azobisisobutyronitrile as a radical polymerization initiator. Then, the inside of the ampoule was repeatedly purged with nitrogen and degassed, and then sealed, and bulk polymerization was carried out at 40° C. for 48 hours.

After polymerization, the contents were dissolved in benzene, poured into a large amount of methanol to precipitate the polymer, separated in a furnace, thoroughly washed with methanol, and dried under reduced pressure to obtain poly(diisopropyl fumarate) (hereinafter referred to as PDIPF) with a molecular weight of 235,000. ) was obtained.

After providing a transparent substrate 2 of ITO (indium tin oxide, intensified indium, tin oxide) (10 ohm/a1) with a thickness of 2300 on a glass substrate 4, Chloroform (CH
C1) solution (3/72) was spin-coated at a rotational speed of 4900 to form a thin film 1 of 100 layers. Furthermore, aluminum is vapor-deposited, electrodes 3 are provided, and an MIM type element (IT
O/PDiPF/Al) was created. The obtained MIM type device was incubated in 5 situ under vacuum (10-”tor
r), the current-voltage (J-V) characteristics were measured.

A schematic diagram of the obtained MIM type element is shown in FIG. 1, and the J-V characteristics were measured.

A schematic diagram of the obtained MIM type element is shown in FIG. 1, and the J-V characteristic is shown in FIG. 2.

After providing a transparent substrate of ITO (indium tin oxide, intensified indium, tin oxide) (10 ohm/ci) with a thickness of 2300 on a glass substrate, the sample prepared in Reference Example 1 was placed on the transparent substrate. Chloroform (CHCl, ) of PDiPF
The solution (S■/-) was spin-coated at a rotational speed of 4900 to form a 200-layer thin film. Furthermore, gold was vapor-deposited, electrodes were provided, and MIM type elements (ITO/PDiF'F/Au
) was prepared and its current-voltage (J-V) characteristics were measured under air. The results are shown in FIG.

A transparent substrate of ITO (indium tin oxide, indium oxide, tin oxide) (10 ohm/a1) with a thickness of 2300 mm was provided on a glass substrate, and then the transparent substrate prepared in Reference Example 1 was placed on the transparent substrate. PDiPF chloroform (CHCl,)
The solution (6/-) was spin-coated at a rotational speed of 5000 to form a 300-layer thin film. Furthermore, gold is vapor-deposited and electrodes are provided to form an MIM type element (ITO/PDiPF/Au).
was prepared and its current-voltage (J-V) characteristics were measured under air. The results are shown in FIG.

11'' - After providing a transparent substrate of ITO (indium tin oxide, indium oxide, tin oxide) (10 ohms/aI) with a thickness of 2300 on a glass substrate, polydicyclohexyl fumarate (PDcHF) was placed on the transparent substrate. ) (molecular weight 1
74,000) of chloro*)LtA (CHCl,) @ solution (3 m/d) was spin-coated at a rotational speed of 4,900 to 15
A thin film of 0A was formed. Furthermore, gold was deposited and electrodes were provided to create an MIM type element (ITO/PDiPF/Au'J), and the current-voltage (J-V) characteristics were measured in air.

As a result, characteristics similar to those shown in FIG. 4 were obtained.

11J- After providing a transparent substrate of ITO (indium tin oxide, indium oxide, tin oxide) (10 ohm/-) with a thickness of 2300 on a glass substrate, polydi-tart-butyl fumarate ( PDtBF) (molecular weight 2
58000) in chloroform (CHCl) solution (5■
/-) was spin-coated at a rotational speed of 4900 to form a thin film of 200 layers. Furthermore, gold is evaporated, electrodes are provided, and MI
An M-type element (ITO/PDiPF/Au) was prepared and its current-voltage (J-V) characteristics were measured under air. As a result, characteristics similar to those shown in FIG. 4 were obtained.

Same as in Example 2, except that polyisopropyl-tart-butyl fumarate (PiP/1
BF), polyisopropyl-n-amyl fumarate (P
i P/AmF), polytart-butyl-860
-butyl fumarate (PtB/5BF), polybischloroisopropyl fumarate (PBCI PF), polytart-butyl isoamyl fumarate (PtB/i
AmF), polyisopropyl hexafluoroisopropyl fumarate (P i P / F * l P F )
-Polyisopropyl-perfluorooctylethyl fumarate (P i P / Fat F), polyte
A polymer insulating layer was provided on the substrate using rt-butylperfluorooctylethyl fumarate (ptB/Fi, F) under each condition shown in Table 1. Furthermore, gold or aluminum is vapor-deposited, electrodes are provided, and MIM type elements (
ITO/PDRF/^1) or (ITO/PDRF/A
1) was prepared and the current-voltage (J-V) characteristics were measured under air, and results similar to those shown in Figure 4 were obtained.Table 1 shows the conditions and the film thickness of the polymer insulating layer. .

[Brief explanation of drawings]

1st I! 1 is a schematic diagram of the MIM type device manufactured in Example 1, and FIG. 2 is a schematic diagram of the MIM type device manufactured in Example 1. ! A graph showing the current-voltage characteristics of the device. FIG. 3 is a graph showing the current-voltage characteristics of the device manufactured in Example 2. FIG. 4 is a graph showing the current-voltage characteristics of the device manufactured in Example 3. 1..PDiPF thin film, 2..ITO transparent substrate, 3.
...Electrode, 4...Glass substrate.

Claims (1)

[Scope of Claims] A substrate and a film having a thickness of 50 to 100 mm formed by forming a solution of a fumaric acid diester polymer on the substrate by spin coating.
An electric element having a 0 Å polymer insulating layer and an electrode, in which the fumaric acid diester polymer has the following general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R_1 and R_2 are the same or different. represents a group, and at least one of R_1 and R_2 is a branched alkyl group having 3 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or a carbon number having a substituent having a ring structure having 3 to 14 carbon atoms. 2 to 6 substituted alkyl group, a substituted cycloalkyl group having 3 to 10 carbon atoms or a siloxane hydrocarbon group having a substituent in the ring structure, and the branched alkyl group,
The cycloalkyl group, the substituted alkyl group, the substituted cycloalkyl group, and the siloxane hydrocarbon group may contain a heteroatom or may be substituted with a halogen atom. ) An electric device comprising a repeating unit of a fumaric acid diester represented by: