Patents by Inventor Tadataka Morishita
Tadataka Morishita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 6163713Abstract: In a high frequency transmission line having a dielectric substrate and a conductor line which is provided on the dielectric substrate for allowing electric current to flow therethrough, the conductor line has a non-grain-boundary oxide superconductor layer with twin walls but without grain boundaries. The high frequency transmission line is in the form of a plane circuit. It is preferable that an oriented oxide superconductor layer is provided between the dielectric substrate and the non-grain-boundary oxide superconductor layer.Type: GrantFiled: March 5, 1998Date of Patent: December 19, 2000Assignees: NEC Corporation, Sumitomo Electric Industries, Ltd., International Superconductivity Technology CenterInventors: Katsumi Suzuki, Sadahiko Miura, Takayuki Inoue, Koji Muranaka, Hideaki Zama, Youichi Enomoto, Tadataka Morishita, Shoji Tanaka
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Patent number: 6008162Abstract: The present invention can provide an oxide superconductive film with a smooth surface and at homogeneous thickness on a simple substrate structure at a high film formation rate. In a liquid phase epitaxial growth method for producing an ReBa.sub.2 Cu.sub.3 Ox film (3) (Rerepresents one selected from lanthanoids such as Y and Nd, and X represents the oxygen amount) having a 123 type crystal structure from a molten liquid (1), a substrate (2) surface is inclined by 1 degree to 44 degrees with respect to the molten liquid surface at the time of separating the film from the molten liquid after film formation. After separating the film from the molten liquid, the substrate is rotated at 300 rpm to 3000 rpm for 5 seconds to 5 minutes. The film formation atmosphere contains 2 at. % of oxygen and 98 at. % of nitrogen, and the film formation temperature is 900 to 970.degree. C.Type: GrantFiled: March 31, 1998Date of Patent: December 28, 1999Assignees: NEC Corporation, International Conductivity Technology CenterInventors: Sadahiko Miura, Tadataka Morishita, Youichi Enomoto
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Patent number: 5837053Abstract: A single crystal material is prepared by forming a layer of an amorphous substance over a surface of a substrate of a single crystal having the same chemical composition as that of the amorphous substance, the resulting composite material is heated to epitaxially grow the amorphous layer into a single crystal layer. A composite material for producing such a single crystal material is also disclosed which includes a substrate of a single crystal, and a layer of an amorphous substance having the same chemical composition as that of the substrate, the layer having such a thickness that the layer as a whole can epitaxially grow to make a single crystal layer.Type: GrantFiled: November 28, 1995Date of Patent: November 17, 1998Assignee: International Superconductivity Technology CenterInventors: Furen Wang, Tadataka Morishita
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Patent number: 5747427Abstract: Disclosed is a method of forming a thin junction film including a first thin oxide flilm presenting a superconductivity and second thin oxide film presenting an insulator properties or possibly semiconductive properties with an improved production efficiency as well as improved film quality and characteristics. Employed are first and second targets each having substantially the same chemical composition excepting oxygen content. The first target is sputtered at a target cathode voltage of minus 100 V by the use of voltage derived from an external D.C. voltage source, thereby forming a first thin oxide film. Subsequently, the target is changed over to the second target while changing the target cathode voltage into self-bias voltage of minus 50 V without any change of the other film formation conditions.Type: GrantFiled: April 26, 1996Date of Patent: May 5, 1998Assignees: Hokkaido Electric Power Co., Inc., International Superconductivity Technology CenterInventors: Norio Homma, Tadataka Morishita
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Patent number: 5679625Abstract: A method of making a superconducting thin film of a Y--Ba--Cu--O series material by using a diode parallel plate type sputtering apparatus including a vacuum chamber, a substrate disposed within the vacuum chamber and having a substantially flat surface on which the superconducting thin film is to be formed, and a plate-shaped target functioning as a cathode and disposed within the vacuum chamber to parallelly face to the flat surface of the substrate, the target being made of the same material as the superconducting thin film, a plasma gas being introduced into the vacuum chamber, and a voltage being applied between the cathode and the substrate, wherein the method comprises the steps of applying a high frequency voltage having a frequency higher than 40 MHz between the cathode and the substrate to generate plasma of the introduced gas, superimposing a DC voltage (V) on the high frequency voltage in a polarity that the cathode becomes negative, and setting the DC voltage at a value where the DC voltage is suType: GrantFiled: November 22, 1995Date of Patent: October 21, 1997Assignees: Nippon Steel Corporation, International Superconductivity Technology Center, Mitsubish Electric Corporation, Hokkaido Electric Power Co., Inc.Inventors: Wataru Ito, Tadataka Morishita, Norio Homma, Yukihisa Yoshida
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Patent number: 5650376Abstract: A superconducting film is disclosed which has the following composition:(Nd, Ba).sub.3 Cu.sub.3 O.sub.7-dwhere d is a number greater than 0 but smaller than 0.5. The superconducting film has the same crystal structure as that of YBa.sub.2 Cu.sub.3 O.sub.7 except that part of the Nd sites and/or part of the Ba sites are occupied by Ba and Nd atoms, respectively.Type: GrantFiled: November 6, 1995Date of Patent: July 22, 1997Assignee: International Superconductivity Technology CenterInventors: Massoud Badaye, Tadataka Morishita, Youichi Enomoto, Shoji Tanaka
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Patent number: 5635716Abstract: The atoms constituting a surface of a solid sample are identified by first forming, on the surface, island-like deposits of a substance capable of generating fluorescent X-rays upon being energized by an electron beam. The deposits are then energized with the electron beam so that fluorescent X-rays are emitted therefrom and reflected on the surface. From the critical angle for total reflection of the fluorescent X-rays reflected on that portion of the surface of the sample on which no deposits are present, the atoms constituting the surface may be determined. An apparatus for carrying out the above method is also disclosed which is a modification of the conventional RHEED/TRAXS device.Type: GrantFiled: March 13, 1996Date of Patent: June 3, 1997Assignee: International Superconductivity Technology CenterInventors: Ziyuan Liu, Tadataka Morishita
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Patent number: 5466665Abstract: A method of manufacturing YBCO superconducting thin films is obtained which is capable of providing superconducting thin films having excellent crystallinity in a high yield by introducing a new film formation parameter in a hybrid plasma sputtering method. When a Y--Ba--Cu--O type superconducting thin film is formed by using a parallel plate sputtering method, a high-frequency voltage generated by a high-frequency power source is superimposed on a DC voltage generated by a DC power source and applied to the cathode electrode at the same time, an electrically conductive YBCO target is placed on the cathode, and the film formation conditions are controlled on the basis of the difference between the voltage drops in each ion sheath formed on the substrate and directly on the target by applying a DC voltage to a substrate holder from the DC power source.Type: GrantFiled: June 16, 1994Date of Patent: November 14, 1995Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Steel Corporation, International Superconductivity Technology CenterInventors: Yukihisa Yoshida, Wataru Ito, Tadataka Morishita
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Patent number: 5421890Abstract: Disclosed is an oxide thin film producing method and apparatus for producing an oxide thin film having excellent crystallinity and purity with high productivity while correctly controlling the composition of the oxide thin film. After reducing the pressure inside a vacuum chamber to 1.times.10.sup.-9 Torr or less, a metal thin film is formed by evaporating a specified metal element and depositing vapor of the metal element on a substrate in the vacuum chamber. Then a cover member is moved upward to closely abut to a cover receiving member to thereby form an airtight chamber for enclosing the substrate airtightly in the vacuum chamber. With the degree of vacuum around the airtight chamber maintained, O.sub.2 gas is directly introduced into the airtight chamber through a gas piping to oxidize the metal thin film and thereby form an oxide thin film. At the same time, the gas inside the airtight chamber is discharged directly out of the vacuum chamber through a gas piping.Type: GrantFiled: July 29, 1993Date of Patent: June 6, 1995Assignees: International Superconductivity Technology Center, Sharp Kabushiki Kaisha, Kabushiki Kaisha Kobe Seiko ShoInventors: Ryusuke Kita, Takashi Hase, Masato Sasaki, Tadataka Morishita
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Patent number: 5420103Abstract: A LnBaCuO-series superconducting thin film is provided over a surface of a substrate of Y.sub.2 O.sub.3 single crystal to form a composite superconductor. Ln stands for Y or a lanthanoid element. The composite superconductor has an improved interfacial diffusion.Type: GrantFiled: August 19, 1993Date of Patent: May 30, 1995Assignee: International Superconductivity Technology CenterInventors: Akira Oishi, Tadataka Morishita
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Patent number: 5369275Abstract: An apparatus for solid surface analysis capable of carrying out the X-ray fluorescence analysis of the sample surface according to the characteristic X-rays detected by the energy dispersive X-ray detector. The apparatus can also obtain an enlarged image of the sample surface according to the secondary electrons emitted from the excited sample surface detected by the electron detector. The apparatus can also carry out an X-ray diffraction analysis of the sample surface according to diffracted X-rays detected by the diffracted X-ray detector. The apparatus is also capable of attaching or detaching the energy dispersive X-ray detector easily by incorporating a connection room which can be put in a vacuum state independent of the vacuum chamber.Type: GrantFiled: July 10, 1992Date of Patent: November 29, 1994Assignees: International Superconductivity Technology Center, Fujikura Ltd., Showa Electric Wire & Cable Co., Ltd.Inventors: Toshio Usui, Yuji Aoki, Masayuki Kamei, Tadataka Morishita
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Patent number: 5350738Abstract: The present invention provides a method of manufacturing a high quality oxide superconductor film capable of controlling the film-forming rate and the film composition easily and forming the superconductor film safely and economically, over a wide region and homogeneously, wherein each of elements of R in which R represents one or more of elements selected from the group consisting of Y and lanthanide series rare earth elements, Ba and Cu is vapor deposited in the state of metal on a substrate under a high vacuum of lower than 10.sup.-8 Torr by a vacuum vapor deposition process to form a precursor comprising an amorphous metal and the precursor is oxidized and crystallized by applying a heat treatment without taking out the same into the atmospheric air.Type: GrantFiled: November 27, 1992Date of Patent: September 27, 1994Assignees: International Superconductivity Technology Center, Kabushiki Kaisha Kobe Seiko Sho, Sharp Kabushiki KaishaInventors: Takashi Hase, Ryusuke Kita, Masato Sasaki, Tadataka Morishita
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Patent number: 5310707Abstract: A substrate material for the preparation of an oxide superconductor includes two different rare earth elements A' and A" in the IIIa group, Ga, and 0, the atomic ratio of these elements being expressed as A'1-xA"xGaO.sub.3 (where 0<x<1), and a mixed crystal material forming a perovskite-type structure having a composition of AGaO.sub.3 with A being at least one of the two rare earth elements A' and A" in the IIIa group, a substrate material for preparing an oxide superconductor includes a mixed crystal material made up of Nd, La, Ga, and O in an atomic ratio of La.sub.1-x Nd.sub.x GaO.sub.3 wherein 0.2.ltoreq.x<1.0, the substrate material forming a GdFeO.sub.3 -type structure; a substrate material for preparing an oxide superconductor includes a mixed material made up of Nd, A.sup.1, Ga, and O in an atomic ratio of A.sup.1.sub.1-x Nd.sub.x GaO.sub.3 where A.sup.1 is a rare earth element excluding La and Nd, and 0.2.ltoreq.x<1.0, the mixed crystal material forming a GdFeO.sub.3 -type structure.Type: GrantFiled: September 28, 1992Date of Patent: May 10, 1994Assignee: Superconductivity Research Laboratory InternationalInventors: Akira Oishi, Toshio Usui, Hidekazu Teshima, Tadataka Morishita
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Patent number: 5281575Abstract: In manufacturing a high-temperature superconductive oxide thin film by irradiating a laser beam onto an oxide target in an atmosphere of oxygen to form the high-temperature superconductive oxide thin film on an oxide substrate, the laser beam is irradiated from a back surface of the substrate and is transmitted through the substrate, and thereafter the laser beam is irradiated onto the oxide target.Type: GrantFiled: April 21, 1992Date of Patent: January 25, 1994Assignees: International Superconductivity Technology Center, Kabushiki Kaisha Kobe Seiko Sho, Hitachi Densen Kabushiki KaishaInventors: Takashi Hase, Tadataka Morishita, Katsumi Ohata, Hirohiko Izumi
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Patent number: 5254363Abstract: Disclosed is an oxide thin film producing method for producing an oxide thin film having excellent crystallinity and purity with high productivity while correctly controlling the composition of the oxide thin film. After reducing the pressure inside a vacuum chamber to 1.times.10.sup.-9 Torr or less, a metal thin film is formed by evaporating a specified metal element and depositing vapor of the metal element on a substrate in the vacuum chamber. Then a cover member is moved upward to closely abut to a cover receiving member to thereby form an airtight chamber for enclosing the substrate airtightly in the vacuum chamber. With the degree of vacuum around the airtight chamber maintained, O.sub.2 gas is directly introduced into the airtight chamber through a gas piping to oxidize the metal thin film and thereby form an oxide thin film. At the same time, the gas inside the airtight chamber is discharged directly out of the vacuum chamber through a gas piping.Type: GrantFiled: July 10, 1992Date of Patent: October 19, 1993Assignees: Int'l Superconductivity Tech. Center, Kabushiki Kaisha, Kabushiki Kaisha Kobe Seiko IhoInventors: Ryusuke Kita, Takashi Hase, Masato Sasaki, Tadataka Morishita
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Patent number: 5225393Abstract: A process for forming a thin oxide film on an underlying surface adapted for film formation thereon according to a radio frequency magnetron sputtering method using an oxide target(s). The excitation frequency is a frequency which is higher than 13.56 MHz and which provides a negative target self-bias voltage permitting of film formation.Type: GrantFiled: January 10, 1992Date of Patent: July 6, 1993Assignees: International Superconductivity Technology Center, Oki Electric Industry Co., Ltd., The Hokkaido Electric Power Company Inc., The Chugoku Electric Power Co., Inc., Mitsubishi Materials CorporationInventors: Norio Homma, Hiromi Takahashi, Shinji Kawamoto, Hideyuki Kondo, Tadataka Morishita