JPH0666226B2 - Capacitor - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor used in various electronic devices.

2. Description of the Related Art Capacitors made of plastic films, metallized films, ceramics, etc. have been used as dielectrics.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention provides a new type capacitor using an organic thin film obtained by electrolytic polymerization without incorporating the above-mentioned dielectric layer.

Means for Solving the Problems The present invention can be obtained by electropolymerization of a compound containing at least one group of a carbon ring, a nitrogen-containing ring, a selenium-containing ring, an oxygen-containing ring and an amino aromatic ring in a molecule. An insulating thin film made of various organic or non-oxide inorganic substances or highly stable metallic high valence substances is formed on the conductor of the organic thin film or the film surface of the semiconductor characteristic region, and the insulating thin films are stacked and stacked. An aluminum electrode is provided on the film surface, and a metal other than aluminum is directly attached to the other surface to form an electrode.

The above-mentioned different metal electrode may be used as a positive electrode material in the form of a foil or the like during electrolytic polymerization, which has become a polymer film-adhered body, and the polymer film may be separated from the metal foil. Then, the metal film electrode may be newly formed by the vapor deposition method.
Further, these electropolymerized films are washed with pure water, a pure solvent or the like after the film formation to remove free salts, residual solvents, unreacted monomers and the like, and dried and then subjected to the above-mentioned processing.

Monomers used for electrolytic polymerization include pyrrole, furan,
There are selenophene, paraphenylene, anthracene, azulene, aniline, etc., and salts used as supporting electrolytes during electrolytic polymerization include lithium borofluoride, paratoluene sulfonate, silver perchlorate, lithium perchlorate, copper chloride, borofluoride. There are tetrabutylamine, tetrabutylamine perchlorate, and the like, and these are used alone or in combination. Benzonitrile, acetonitrile, nitrobenzene,
Ortho-dichlorobenzene, dimethyl sulfate, water, etc.

There are various methods for forming the above-mentioned insulating thin film.

That is, it is a method of forming an organic thin film as a substrate on this surface. A vacuum deposition method, a plasma polymerization method, a sputtering method, a Langmuir-Blodgett (LB) film method and the like are possible.

Is a high-valence oxide of a stable metal such as SiO ₂ , Al ₂ O ₃ , or Ti ₂ which is subjected to resistance heating and vacuum deposition by a heating source such as an electron beam. Is styrene, methyl methacrylate, toluene,
A thin film is formed by plasma polymerizing an organic substance such as SiCl ₄ , paraxylene, an inorganic compound or an organometallic compound.
Is a thin film formed by sputtering using a metal high valence oxide such as Al ₂ O ₃ , SiO ₂ , or SiC, or a non-oxide inorganic compound as a source. Develops a long-chain alkyl soap, amphipathic polymer, etc. on the water surface and pulls up on the substrate to form a laminated film.

The present inventors formed the above-mentioned various insulating thin films on one surface of the conductors and semiconductor characteristic regions of the various organic thin films obtained by the above-mentioned electrolytic polymerization, and stacked and vacuum-deposited aluminum on this insulating thin film. System, various experiments, research results,
In a system in which the above-mentioned two-layer thin film is formed on one surface and a metal other than aluminum is directly adhered on the other surface, an electrode function produces a capacitor with extremely large capacity and small leakage current, and further insulation It has been found that it shows a much higher withstand voltage than the system without a film. It was also confirmed at the same time that the insulating film did not contribute to the excellent dielectric properties of these capacitors, but that this property was achieved due to the electrode action of the electrolytically polymerized film.

In addition, as the above-mentioned different kind of metal, it is preferable to use a metal having a work relationship larger than that of aluminum.

Examples Tables show configurations and characteristics of various capacitors according to Examples.

The pyrrole, furan, and aniline polymers used here are those having a film thickness of 5 μm, which are obtained by electrolytic polymerization of benzonitrile-lithium perchlorate system, acetonitrile-lithium borofluoride system, and water-paratoluenesulfonate system, respectively. ,
The Ni and Co foils used for the electrode B are both 6 μm thick.
Further, each insulating film and its forming method are represented by chemical symbols and the above-mentioned ,,, and the film thickness is also described.

It should be noted that V ₁ is the withstand voltage of Al directly vacuum-deposited without an insulating thin film, and V ₂ is that of Al vacuum-deposited on each insulating film. Further, these capacitors were polar, and high withstand voltage was obtained when the aluminum electrode side was positive, and the values in the table are the values at this time.

As is clear from the table, these capacitors show extremely large capacitance, their leakage current is small, and their withstand voltage is greatly improved.

The above-mentioned insulating thin film was effective in the film thickness range of 50 to 700Å, and showed the maximum effect in the film thickness of 50 to 200Å.

The polymer thin film could be electrically controlled by setting the conditions during electrolysis, could be made into a uniform ultrathin film, and a long film having a thickness of 1 μm or less and a wide film could be obtained. Even with this film thickness, the various characteristic values in the table were maintained, and even some of the characteristics were improved.
From this film, capacitors with a wound structure or a laminated structure could be manufactured.

Similar results were obtained with other organic thin films and electrode systems.

Effect of the Invention According to the present invention, due to the electrode effect of various electrolytically polymerized thin films,
It is possible to obtain a capacitor having a large capacity, a small leakage current, and a high withstand voltage. By making the polymer film ultra-thin, a further compact, lightweight and dry type capacitor can be obtained.

Claims (1)

[Claims] 1. An organic compound on one surface of an organic thin film obtained by electrolytic polymerization of a compound containing at least one of a carbon ring, a nitrogen-containing ring, a selenium-containing ring, an oxygen-containing ring and an amino aromatic ring in the molecule. Forming an insulating thin film made of a non-oxide inorganic compound or a high valent oxide of a metal, providing an electrode made of aluminum on the film surface of the insulating thin film, and providing the electrode on the other surface of the organic thin film. Is a capacitor having electrodes made of different metals.