Hitachi, Ltd.

Hitachi Maxell, Limited

Katsuki Miyauchi

Tetsuichi Kudo

Kazumasa Takagi

Tokuumi Fukazawa

Keiichi Kanehori

Yukio Ito

Masahiko Hiratani

Toshiyuki Aida

Hiroshi Okamoto

Yukio Okamoto

Fumiyoshi Kirino

Toshiaki Masuhara

Osamu Minato

Akira Ishikawa

Shinji Takayama

Gyozo Toda

Iwao Matsuyama

Yoshimi Kawanami

Masaaki Futamoto

Katsuhiro Shimohigashi

Masaharu Kubo

Yukio Honda

Ushio Kawabe

Takahiko Kato

Fumio Murai

Toshikazu Nishino

Shinji Okazaki

Yutaka Misawa

Tsuneo Suganuma

Katsuzo Aihara

Haruhiro Hasegawa

Yoshihide Wadayama

Jiro Kuniya

Takao Iwayanagi

Tetsu Oi

Yoshio Uetani

Yuuichi Madokoro

Tsune Miyashita

Masahiro Ogihara

Shigeru Jyomura

Tsuyoshi Seko

Shin'ichiro Saitoh

Chemical reactions of superconducting raw materials with active oxygen atoms and their charged particles are accelerated by using at least oxygen plasma in the fabrication process of a superconductive body. Thereby an ionic crystal is grown in a short time, which provides stable superconducting materials of high quality such as high critical temperature and low resistivity. In another aspect, a substrate is irradiated simultaneously with streams of vapor of metal elements, of which a superconductive body is to be composed, and a stream of gas of ions generated in a plasma chamber and film growth is effected while keeping the substrate at a temperature higher than 400.degree. C. to produce a ceramic type superconductive thin film.

Method for fabricating superconducting materials and superconductive

A superconducting oxide composition comprising Ln-Th-Cu-O wherein Ln indicates at least one element selected from a group consisting of Pr, Nd, Pm, Sm, Eu, Gd and Er. A superconducting structure is formed in such a manner that at least an insulating layer is sandwiched between two superconductor layers but the superconductor layers are electrically coupled with each other, and a superconducting device including the superconducting structure is constructed so as to perform a switching operation for an electric signal, to detect a light signal, and to detect the intensity of a magnetic field. Another superconducting device is formed so that two superconductor layers are put in direct contact with each other, and a tunnel current between the superconductor layers can be controlled. Further, a superconductor structure is formed which includes a plurality of superconductor layers and has a superconducting transition temperature or superconducting critical current higher than that of each superconductor layer, and a superconducting device including this superconducting structure can operate at a relatively high temperature. Furthermore, a superconducting circuit device is formed which can emit a coherent electromagnetic wave having a wavelength of the order of 10 .mu.m on the basis of the difference in energy gap between adjacent superconductor layers. Additionally, novel oxide superconductor materials are disclosed.

Superconducting composition comprising Ln-Th-Cu-O, wherein Ln is Pr, Nd,

A process for controlling an oxygen content of a non-superconductive or superconductive oxide is provided, in which a beam of particles such as ions, electrons or neutrons or an electromagnetic radiation is applied to the non-superconductive or superconductive oxide of a perovskite type such as YBa.sub.2 Cu.sub.3 O.sub.7-x, thereby increasing or reducing the oxygen content of the oxide at the sites of oxygen in the crystal lattice of the oxide. Furthermore, a superconductive device such as a superconductive magnet, superconductive power transmission wire, superconductive transformer, superconductive shield, permanent current switch and electronic element is made by utilizing the process for controlling the oxygen concentration of the superconductive oxide.

Process for controlling oxygen content of superconductive oxide,

A weak-link Josephson junction is of the type employing a thin film of an oxide superconductor, in which a crystal grain boundary produced reflecting an artificial crystal defect is utilized as the weak-link junction. The crystal grain boundary is formed concretely by a method in which atoms of different species are deposited on the predetermined part of the surface of a substrate, the predetermined part of the surface of a substrate is disturbed, or parts of different crystal face orientations are formed at the surface of a substrate, whereupon the superconducting thin film is epitaxially grown on the substrate, or by a method in which the predetermined part of the superconducting thin film, epitaxially grown on a substrate, is diffused with atoms of different species hampering a superconductivity, or the predetermined part of the superconducting thin film is disturbed, whereupon the superconducting thin film is annealed.

Method of forming weak-link Josephson junction, and superconducting

A radiation-sensitive material comprising a polyacid composed of tungsten and niobium, titanium and/or tantalum. A uniform film can be formed by an easy spin coating method. The polyacid has a radiation sensitivity higher than that of a polyacid comprising only tungsten.

Radiation sensitive materials

A material for an optical component comprising polytungstic acid having peroxo groups, and an optical component, at least part of which is constituted of a thin film of the above-mentioned material. By using this material, a thin film of an inorganic material having an excellent stability is formed by the inexpensive wet painting method. An optical component using the above-mentioned thin film can be formed on an arbitrary substrate with high accuracy at a low temperature of about 100.degree. C. or below. The polytungstic acid may contain carbon as a heteroatom and/or may have Nb, Ti, V, Ta and/or Mo substituted for part of W.

Material for micro optical component and optical component using the same

A process for fabricating a superconducting oxide thin film is disclosed which comprises the steps of separately evaporating metal elements, of which the superconducting oxide thin film with a desired stoichiometry is to be composed, to a substrate and simultaneously irradiating the substrate with oxygen plasma generated by RF wave or ECR microwave to form a crystalline oxide film without further annealing.

Method for fabricating superconducting oxide thin films by activated

A semiconductor memory using a dynamic memory device, wherein a battery supplies a power source voltage and a substrate bias voltage when the memory is cut off from an external device, and a refresh control circuit changes in refresh timing of the memory device in accordance with the leakage current of the memory device. The power consumption of the memory can thus be reduced and the data can be kept for an extended period without an external power source.

Semiconductor memory having circuit effecting refresh on variable cycles

A compact, light-weight all solid state lithium battery is disclosed. The battery provides a good contact between a solid electrolyte and a Li anode by forming a Li alloy layer therebetween, even at the time of discharge at a large current density.

Solid state lithium battery

The present invention relates to a titanium disulfide film fabricated on a substrate, where crystallites of titanium disulfide is oriented at an angle of their c-axis to the substrate surface of not more than 45.degree., and to a process for fabricating the film, where the film is prepared by chemical vapor deposition from TiCl.sub.4 and H.sub.2 S as source gases under an inner pressure of reaction tube of 30 kPa or less.

Titanium disulfide thin film and process for fabricating the same

A cathode structure for a thin film battery in which a titanium oxide layer is disposed on a substrate and has a titanium disulfide thin film disposed thereon. The cathode structure exhibits an excellent performance when applied to a lithium battery, a sodium battery, etc.

Cathode structure for thin film battery

A nonvolatile memory in which at least one power supply element is carried with an integrated circuit chip containing the memory and connected to power supply terminals of the integrated circuit chip having a memory cell array in which a plurality of memory elements or memory circuits are arrayed.

Semiconductor integrated circuit

The invention relates to a lithium oxide-based amorphous ionic conductor which is a ternary composition consisting of Li.sub.2 O, SiO.sub.2 and ZrO.sub.2, said composition having a composition of components falling within the range of a quadrilateral defined by two lines corresponding to the Li.sub.2 O contents of 80% and 50%, respectively, and by two lines which pass the apex of Li.sub.2 O and on which a ratio SiO.sub.2 :ZrO.sub.2 is 100:0.5 and 1:9, respectively. The conductor is used as a solid electrolyte in the form of a high ionic conductive amorphous thin film.

Lithium oxide-based amorphous ionic conductor

Disclosed is a lithium oxide based amorphous material having a composition included in a region defined by lines connecting points A, B, C and D in the composition diagram of the ternary system of Li.sub.2 O.SiO.sub.2.P.sub.2 O.sub.5 shown in FIG. 1 of the accompanying drawings. This amorphous material can be formed by performing sputtering by using as a target a mixture of a lithium silicate/lithium phosphate composition and LiO.sub.2. This amorphous material is excellent in the ionic conductivity.

Lithium oxide based amorphous material and process for preparation

A pulse generator comprising an induction element, and a nonlinear condenser whose dielectric material portion is made of ferroelectric ceramics represented by a general formula of (Pb.sub.1-x-y, Ba.sub.x, Sr.sub.y)(Ti.sub.z, Zr.sub.1-z)O.sub.3.

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Hino, Japan

Katsuki Miyauchi