Patents by Inventor Hiroaki Saitoh
Hiroaki Saitoh 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: 11955558Abstract: One conductor region of a crystalline silicon semiconductor layer in a first transistor is electrically connected to one conductor region of an oxide semiconductor layer in a second transistor through a first contact hole and a second contact hole communicating with each other.Type: GrantFiled: April 26, 2019Date of Patent: April 9, 2024Assignee: SHARP KABUSHIKI KAISHAInventors: Atsushi Hachiya, Hiroaki Furukawa, Yuhichi Saitoh, Tomohisa Aoki
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Publication number: 20240085752Abstract: An active matrix substrate includes: a thin film transistor located in each pixel region; and a pixel electrode electrically coupled with the thin film transistor. The thin film transistor includes a lower gate electrode, a lower gate insulating layer, an oxide semiconductor layer, an upper gate insulating layer, and an upper gate electrode. The width of an upper gate line electrically coupled with the upper gate electrode is greater than the width of a lower gate line electrically coupled with the lower gate electrode.Type: ApplicationFiled: August 24, 2023Publication date: March 14, 2024Inventors: Atsushi HACHIYA, Hiroaki FURUKAWA, Yuhichi SAITOH
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Patent number: 11522055Abstract: A stack including at least a semiconductor drift layer stacked on a single-crystal diamond substrate having a coalescence boundary, wherein the coalescence boundary of the single-crystal diamond substrate is a region that exhibits, in a Raman spectrum at a laser excitation wavelength of 785 nm, a full width at half maximum of a peak near 1332 cm?1 due to diamond that is observed to be broader than a full width at half maximum of the peak exhibited by a region different from the coalescence boundary, the coalescence boundary has a width of 200 ?m or more, and the semiconductor drift layer is stacked on at least the coalescence boundary.Type: GrantFiled: January 11, 2019Date of Patent: December 6, 2022Assignee: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGYInventors: Shinya Ohmagari, Hideaki Yamada, Hitoshi Umezawa, Nobuteru Tsubouchi, Akiyoshi Chayahara, Yoshiaki Mokuno, Akinori Seki, Fumiaki Kawai, Hiroaki Saitoh
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Publication number: 20210066078Abstract: There is provided a novel stack that includes a single-crystal diamond substrate having a coalescence boundary, yet effectively uses the coalescence boundary. A stack comprising at least a semiconductor drift layer stacked on a single-crystal diamond substrate having a coalescence boundary, wherein the coalescence boundary of the single-crystal diamond substrate is a region that exhibits, in a Raman spectrum at a laser excitation wavelength of 785 nm, a full width at half maximum of a peak near 1332 cm?1 due to diamond that is observed to be broader than a full width at half maximum of the peak exhibited by a region different from the coalescence boundary, the coalescence boundary has a width of 200 ?m or more, and the semiconductor drift layer is stacked on at least the coalescence boundary.Type: ApplicationFiled: January 11, 2019Publication date: March 4, 2021Inventors: Shinya OHMAGARI, Hideaki YAMADA, Hitoshi UMEZAWA, Nobuteru TSUBOUCHI, Akiyoshi CHAYAHARA, Yoshiaki MOKUNO, Akinori SEKI, Fumiaki KAWAI, Hiroaki SAITOH
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Patent number: 9587327Abstract: A method of production of a SiC single crystal uses the solution method to prevent the formation of defects due to seed touch, i.e., causing a seed crystal to touch the melt, and thereby cause growth of a SiC single crystal reduced in defect density. According to the method, a SiC seed crystal touches a melt containing Si in a graphite crucible to thereby cause growth of the SiC single crystal on the SiC seed crystal. The method includes making the SiC seed crystal touch the melt, and then making the melt rise in temperature once to a temperature higher than the temperature at the time of touch and also higher than the temperature for causing growth.Type: GrantFiled: July 17, 2009Date of Patent: March 7, 2017Assignee: Toyota Jidosha Kabushiki KaishaInventors: Katsunori Danno, Akinori Seki, Hiroaki Saitoh, Yoichiro Kawai
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Patent number: 9508802Abstract: A process for producing a semiconductor device includes: forming an SiC epitaxial layer on an SiC substrate; implanting the epitaxial layer with ions; forming a gettering layer having a higher defect density than a defect density of the SiC substrate; and carrying out a heat treatment on the epitaxial layer. The semiconductor device includes an SiC substrate, an SiC epitaxial layer formed on the SiC substrate, and a gettering layer having a higher defect density than a defect density of the SiC substrate.Type: GrantFiled: May 4, 2012Date of Patent: November 29, 2016Assignees: Toyota Jidosha Kabushiki Kaisha, Kyoto UniversityInventors: Katsunori Danno, Hiroaki Saitoh, Akinori Seki, Tsunenobu Kimoto
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Publication number: 20150064882Abstract: A process for producing a semiconductor device includes: forming an SiC epitaxial layer on an SiC substrate; implanting the epitaxial layer with ions; forming a gettering layer having a higher defect density than a defect density of the SiC substrate; and carrying out a heat treatment on the epitaxial layer. The semiconductor device includes an SiC substrate, an SiC epitaxial layer formed on the SiC substrate, and a gettering layer having a higher defect density than a defect density of the SiC substrate.Type: ApplicationFiled: May 4, 2012Publication date: March 5, 2015Inventors: Katsunori Danno, Hiroaki Saitoh, Akinori Seki, Tsunenobu Kimoto
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Patent number: 8399888Abstract: A p-type SiC semiconductor includes a SiC crystal that contains Al and Ti as impurities, wherein the atom number concentration of Ti is equal to or less than the atom number concentration of Al. It is preferable that the concentration of Al and the concentration of Ti satisfy the following relations: (Concentration of Al)?5×1018/cm3; and 0.01%?(Concentration of Ti)/(Concentration of Al)?20%. It is more preferable that the concentration of Al and the concentration of Ti satisfy the following relations: (Concentration of Al)?5×1018/cm3; and 1×1017/cm3?(Concentration of Ti)?1×1018/cm3.Type: GrantFiled: November 19, 2009Date of Patent: March 19, 2013Assignee: Toyota Jidosha Kabushiki KaishaInventors: Hiroaki Saitoh, Akinori Seki, Tsunenobu Kimoto
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Publication number: 20130042802Abstract: The present invention provides a method of production of SiC single crystal using the solution method which prevents the formation of defects due to causing a seed crystal to touch the melt for seed touch, and thereby causes growth of an Si single crystal reduced in defect density. The method of the present invention is a method of production of an SiC single crystal which causes an SiC seed crystal to touch a melt containing Si in a graphite crucible to thereby cause growth of the SiC single crystal on the SiC seed crystal, characterized by making the SiC seed crystal touch the melt in the state where the C is not yet saturated.Type: ApplicationFiled: July 17, 2009Publication date: February 21, 2013Inventors: Katsunori Danno, Akinori Seki, Hiroaki Saitoh, Kawai Yoichiro
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Publication number: 20120118221Abstract: The present invention provides a method of production of an SiC single crystal using the solution method which prevents the formation of defects due to seed tough, i.e., causing a seed crystal to touch the melt, and thereby causes growth of an Si single crystal reduced in defect density. The method of the present invention is a method of production of an SiC single crystal by causing an SiC seed crystal to touch a melt containing Si in a graphite crucible to thereby cause growth of the SiC single crystal on the SiC seed crystal, characterized by making the SiC seed crystal touch the melt, then making the melt rise in temperature once to a temperature higher than the temperature at the time of touch and also higher than the temperature for causing growth.Type: ApplicationFiled: July 17, 2009Publication date: May 17, 2012Inventors: Katsunori Danno, Akinori Seki, Hiroaki Saitoh, Yoichiro Kawai
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Publication number: 20120121231Abstract: Provided is a digital broadcast receiver having a recording function, which is capable of automatically selecting a recording destination of reserved recording.Type: ApplicationFiled: June 24, 2010Publication date: May 17, 2012Inventors: Hiroaki Saitoh, Yukimi Kawaguchi, Nobuyuki Murashima, Tadamichi Atsumi, Toru Hirota
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Publication number: 20110210341Abstract: A p-type SiC semiconductor includes a SiC crystal that contains Al and Ti as impurities, wherein the atom number concentration of Ti is equal to or less than the atom number concentration of Al. It is preferable that the concentration of Al and the concentration of Ti satisfy the following relations: (Concentration of Al)?5×1018/cm3; and 0.01%?(Concentration of Ti)/(Concentration of Al)?20%. It is more preferable that the concentration of Al and the concentration of Ti satisfy the following relations: (Concentration of Al)?5×1018/cm3; and 1×1017/cm3?(Concentration of Ti)?1×1018/cm3.Type: ApplicationFiled: November 19, 2009Publication date: September 1, 2011Inventors: Hiroaki Saitoh, Akinori Seki, Tsunenobu Kimoto
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Patent number: 7837789Abstract: A method of epitaxial growth of a 4H—SiC single crystal enabling growth of an SiC single crystal with low defects and low impurities able to be used for a semiconductor material at a practical growth rate, comprising growing a 4H—SiC single crystal on a 4H—SiC single crystal substrate by epitaxial growth while inclining an epitaxial growth plane of the substrate from a (0001) plane of the 4H—SiC single crystal by an off-angle of at least 12 degrees and less than 30 degrees in a <11-20> axial direction, and a 4H—SiC single crystal obtained by the same.Type: GrantFiled: May 13, 2005Date of Patent: November 23, 2010Assignees: Toyota Jidosha Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.Inventors: Tsunenobu Kimoto, Hiromu Shiomi, Hiroaki Saitoh
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Publication number: 20090229519Abstract: The present invention provides an apparatus for manufacturing a semiconductor thin film that is capable of manufacturing an even thin film with substantially no adhesion of impurities, and is capable of improving in-plane evenness of a grown thin film. The invention is an apparatus for manufacturing a semiconductor thin film includes a reaction tube 12, a susceptor 20 disposed in the reaction tube 12, and a negative pressure generator, the negative pressure generator applying a negative pressure to a substrate 22A placed on the susceptor 20 to hold the substrate, and the substrate 22A is placed so that an angle of a normal line to a crystal growth face of the substrate 22A to a vertical downward direction is less than 180°.Type: ApplicationFiled: December 20, 2006Publication date: September 17, 2009Inventor: Hiroaki Saitoh
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Publication number: 20070221119Abstract: A method of epitaxial growth of a 4H—SiC single crystal enabling growth of an SiC single crystal with low defects and low impurities able to be used for a semiconductor material at a practical growth rate, comprising growing a 4H—SiC single crystal on a 4H—SiC single crystal substrate by epitaxial growth while inclining an epitaxial growth plane of the substrate from a (0001) plane of the 4H—SiC single crystal by an off-angle of at least 12 degrees and less than 30 degrees in a <11-20> axial direction, and a 4H—SiC single crystal obtained by the same.Type: ApplicationFiled: May 13, 2005Publication date: September 27, 2007Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, SIXON LTDInventors: Tsunenobu Kimoto, Hiromu Shiomi, Hiroaki Saitoh
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Patent number: 5810480Abstract: A rotary shaft is inserted in a bearing bore of a sleeve with lubricant stored therebetween. Upper and lower groove patterns, spaced in a vertical direction for cooperatively generating a dynamic pressure when the rotary shaft rotates in the bearing bore, are formed on at least one of an outside surface of the rotary shaft and an inside surface of the bearing bore. The rotary shaft has a recessed portion in a region located between the upper and lower groove patterns for storing the lubricant therein. The recessed portion is asymmetrically tapered so that the lubricant stored in the recessed portion is chiefly circulated to the upper groove pattern against a gravity acting thereon when the rotary shaft rotates in the bearing bore, whereby the upper and lower groove patterns are uniformly lubricated.Type: GrantFiled: May 30, 1997Date of Patent: September 22, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Takafumi Asada, Hiroaki Saitoh, Tsutomu Hamada
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Patent number: 4730890Abstract: A plug set for optical connector for optical fiber cables arranged to fix reinforcing fibers of an optical fiber cable by at first placing the reinforcing fibers round an outer surface of an end portion of a bushing for inserting the optical fiber cable therein, attaching a thermo-shrinkable tube to the end portion of the bushing after the above so that the reinforcing fibers are covered with the thermo-shrinkable tube and, then, heating the tube so that the tube shrinks, the plug set for optical connector being arranged to thereby fix the reinforcing fibers without using a bonding agent.Type: GrantFiled: November 23, 1982Date of Patent: March 15, 1988Assignee: Dai-Ichi Seiko Co., Ltd.Inventors: Noritake Kashimura, Hiroaki Saitoh
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Patent number: 4636034Abstract: An optical connector for optical fiber cables comprising two ferrules respectively serving to hold end portions of two optical fibers to be connected and a sleeve with a longitudinal through hole having a cross sectional shape of regular hexagon and serving to insert the ferrules thereto, the optical connector being arranged to connect the two optical fibers by respectively inserting the two ferrules to the sleeve from both ends of the sleeve so that the end portions of the two ferrules contact each other in the inside of the sleeve and also arranged that the ferrules can be inserted easily and the ends of the two optical fibers are connected properly.Type: GrantFiled: April 4, 1985Date of Patent: January 13, 1987Assignee: Dai-Ichi Seiko Co., Ltd.Inventors: Noritake Kashimura, Hiroaki Saitoh