Patents by Inventor Takahiro Kozawa

Takahiro Kozawa 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).

  • Publication number: 20210202947
    Abstract: A method for producing a positive electrode active material is provided. The method can prevent a gas generation due to an oxidative degradation of a non-aqueous electrolyte in a lithium-ion secondary battery using a positive electrode active material which operates at a high potential. A method for producing a coated positive electrode active material for a lithium-ion secondary battery includes coating a surface of a positive electrode active material with an oxide-based solid electrolyte by a mechanical coating method and then conducting heat treatment at 300° C. or higher, and the positive electrode active material has an average potential of extraction and insertion of lithium of 4.5V or more and 5.0V or less based on Li+/Li.
    Type: Application
    Filed: March 5, 2021
    Publication date: July 1, 2021
    Applicants: KANEKA CORPORATION, OSAKA UNIVERSITY
    Inventors: Takashi Kikuchi, Kohei Ogawa, Kazuaki Kanai, Makio Naito, Takahiro Kozawa
  • Patent number: 10896831
    Abstract: A supply part includes a first partition, a second partition under the first partition, a third partition under the second partition, a first flow path between the first partition and the second partition allowing a first gas to be introduced therein, a second flow path between the second partition and the third partition allowing a second gas to be introduced therein, a first piping extending from the second partition to reach below the third partition and being communicated with the first flow path, a second piping extending from the third partition to reach below the third partition and being communicated with the second flow path, and a convex portion provided on an outer circumferential surface of the first piping or an inner circumferential surface of the second piping protruding from one of the outer circumferential surface and the inner circumferential surface toward the other one.
    Type: Grant
    Filed: August 31, 2018
    Date of Patent: January 19, 2021
    Assignees: NuFlare Technology, Inc., Showa Denko K.K., Central Research Institute of Electric Power Industry
    Inventors: Kunihiko Suzuki, Naohisa Ikeya, Keisuke Fukada, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hiroaki Fujibayashi, Hideyuki Uehigashi, Masami Naito, Kazukuni Hara, Hirofumi Aoki, Takahiro Kozawa
  • Patent number: 10262863
    Abstract: A method for manufacturing a SiC epitaxial wafer according to one aspect of the present invention includes separately introducing, into a reaction space for SiC epitaxial growth, a basic N-based gas composed of molecules containing an N atom within the molecular structure but having neither a double bond nor a triple bond between nitrogen atoms, and a Cl-based gas composed of molecules containing a Cl atom within the molecular structure, and mixing the N-based gas and the Cl-based gas at a temperature equal to or higher than the boiling point or sublimation temperature of a solid product generated by mixing the N-based gas and the Cl-based gas.
    Type: Grant
    Filed: December 8, 2015
    Date of Patent: April 16, 2019
    Assignees: SHOWA DENKO K.K., Central Research Institute Of Electric Power Industry
    Inventors: Keisuke Fukada, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hideyuki Uehigashi, Hiroaki Fujibayashi, Masami Naito, Kazukuni Hara, Takahiro Kozawa, Hirofumi Aoki
  • Publication number: 20180374721
    Abstract: A supply part includes a first partition, a second partition under the first partition, a third partition under the second partition, a first flow path between the first partition and the second partition allowing a first gas to be introduced therein, a second flow path between the second partition and the third partition allowing a second gas to be introduced therein, a first piping extending from the second partition to reach below the third partition and being communicated with the first flow path, a second piping extending from the third partition to reach below the third partition and being communicated with the second flow path, and a convex portion provided on an outer circumferential surface of the first piping or an inner circumferential surface of the second piping protruding from one of the outer circumferential surface and the inner circumferential surface toward the other one.
    Type: Application
    Filed: August 31, 2018
    Publication date: December 27, 2018
    Inventors: Kunihiko Suzuki, Naohisa Ikeya, Keisuke Fukada, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hiroaki Fujibayashi, Hideyuki Uehigashi, Masami Naito, Kazukuni Hara, Hirofumi Aoki, Takahiro Kozawa
  • Publication number: 20170345658
    Abstract: A method for manufacturing a SiC epitaxial wafer according to one aspect of the present invention includes separately introducing, into a reaction space for SiC epitaxial growth, a basic N-based gas composed of molecules containing an N atom within the molecular structure but having neither a double bond nor a triple bond between nitrogen atoms, and a Cl-based gas composed of molecules containing a Cl atom within the molecular structure, and mixing the N-based gas and the Cl-based gas at a temperature equal to or higher than the boiling point or sublimation temperature of a solid product generated by mixing the N-based gas and the Cl-based gas.
    Type: Application
    Filed: December 8, 2015
    Publication date: November 30, 2017
    Applicants: SHOWA DENKO K.K., Central Research Institute of Electric Power Industry
    Inventors: Keisuke FUKADA, Masahiko ITO, Isaho KAMATA, Hidekazu TSUCHIDA, Hideyuki UEHIGASHI, Hiroaki FUJIBAYASHI, Masami NAITO, Kazukuni HARA, Takahiro KOZAWA, Hirofumi AOKI
  • Patent number: 9184044
    Abstract: A method for manufacturing a semiconductor device is provided with filling a trench by supplying trichlorosilane gas to a substrate where the trench is formed. A relation between a gas concentration of trichlorosilane gas and a film formation speed includes a concentration countergradient condition in which the film formation speed decreases as the gas concentration increases. The filling of the trench is performed under the concentration countergradient condition.
    Type: Grant
    Filed: April 29, 2015
    Date of Patent: November 10, 2015
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takayuki Koyama, Takanori Yamamoto, Kenji Nakashima, Takahiro Kozawa
  • Patent number: 8956458
    Abstract: A vapor deposition device includes a vapor deposition chamber, a heating chamber, a mixing chamber, a first reservoir for storing trichlorosilane gas, and a second reservoir for storing silane gas that reacts with hydrochloric acid gas. The heating chamber communicates with the first reservoir and the mixing chamber, heats the trichlorosilane gas and then supplies the heated gas to the mixing chamber. The mixing chamber communicates with the second reservoir and the vapor deposition chamber, mixes the heated gas supplied from the heating chamber and the silane gas and then supplies the mixed gas to the vapor deposition chamber. A temperature in the heating chamber is higher than a temperature in the mixing chamber.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: February 17, 2015
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Takahiro Kozawa, Kenji Nakashima, Keeyoung Jun, Takahiro Ito
  • Patent number: 8703590
    Abstract: A process for supplying a mixed material gas that includes a chlorosilane gas and a carrier gas to a surface of a substrate heated at 1200 to 1400° C. from a direction perpendicular to the surface is provided. A supply rate of the chlorosilane gas is equal to or more than 200 ?mol per minute per 1 cm2 of the surface of the substrate. The carrier gas includes a hydrogen gas and at least one or more gases selected from argon, xenon, krypton and neon.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: April 22, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Takahiro Ito, Takahiro Kozawa, Kenji Nakashima, Keeyoung Jun
  • Publication number: 20140038395
    Abstract: A vapor deposition device includes a vapor deposition chamber, a heating chamber, a mixing chamber, a first reservoir for storing trichlorosilane gas, and a second reservoir for storing silane gas that reacts with hydrochloric acid gas. The heating chamber communicates with the first reservoir and the mixing chamber, heats the trichlorosilane gas and then supplies the heated gas to the mixing chamber. The mixing chamber communicates with the second reservoir and the vapor deposition chamber, mixes the heated gas supplied from the heating chamber and the silane gas and then supplies the mixed gas to the vapor deposition chamber. A temperature in the heating chamber is higher than a temperature in the mixing chamber.
    Type: Application
    Filed: August 31, 2011
    Publication date: February 6, 2014
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takahiro Kozawa, Kenji Nakashima, Keeyoung Jun, Takahiro Ito
  • Publication number: 20130040441
    Abstract: A process for supplying a mixed material gas that includes a chlorosilane gas and a carrier gas to a surface of a substrate heated at 1200 to 1400° C. from a direction perpendicular to the surface is provided. A supply rate of the chlorosilane gas is equal to or more than 200 ?mol per minute per 1 cm2 of the surface of the substrate. The carrier gas includes a hydrogen gas and at least one or more gases selected from argon, xenon, krypton and neon.
    Type: Application
    Filed: December 8, 2010
    Publication date: February 14, 2013
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Takahiro Ito, Takahiro Kozawa, Kenji Nakashima, Keeyoung Jun
  • Patent number: 7897987
    Abstract: A light-emitting device includes a light-emitting diode, a red light-emitting phosphor layer, a yellow light-emitting phosphor layer, and a blue light-emitting phosphor layer. These layers are stacked in the stacking sequence of the yellow, blue, and red phosphor layers in order of increasing distance from the LED. The stacking sequence of the yellow and blue phosphor layers is first determined in such a manner that these layers do not interact with each other. The stacking sequence of the red and yellow phosphor layers and the stacking sequence of the red and blue phosphor layers are determined by the discriminant D. This determination of the stacking sequence suppresses a reduction in the conversion efficiency of the phosphors due to concentration quenching, improving the emission efficiency of the light-emitting device.
    Type: Grant
    Filed: March 6, 2009
    Date of Patent: March 1, 2011
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Mitsuhiro Inoue, Kenji Ito, Kazuyohi Tomita, Tetsu Kachi, Takahiro Kozawa, Satoru Kato, Tadashi Ichikawa
  • Patent number: 7646036
    Abstract: An object of the invention is to prevent migration of silver contained in an electrode of a Group III nitride-based compound semiconductor light-emitting device. A positive electrode is formed on a p-type layer. In the positive electrode, an ITO light-transmitting electrode layer, a silver alloy reflecting electrode layer, a diffusion-preventing layer in which a Ti layer and a Pt layer are stacked, and a gold thick-film electrode are sequentially stacked on the p-type layer. The reflecting electrode layer made of a silver alloy contains palladium (Pd) and copper (Cu) as additives and also contains oxygen (O). By virtue of this structure, migration of silver from the silver alloy reflecting electrode layer and blackening of the interface between the silver alloy layer and the ITO light-transmitting electrode layer disposed thereunder are prevented, whereby light extraction efficiency can be enhanced.
    Type: Grant
    Filed: February 4, 2008
    Date of Patent: January 12, 2010
    Assignees: Kabushiki Kaisha Toyota Chuo Kenkyusho, Toyoda Gosei Co., Ltd.
    Inventors: Takahiro Kozawa, Kazuyoshi Tomita, Toshiya Uemura, Shigemi Horiuchi
  • Publication number: 20090242917
    Abstract: A light-emitting device includes a light-emitting diode, a red light-emitting phosphor layer, a yellow light-emitting phosphor layer, and a blue light-emitting phosphor layer. These layers are stacked in the stacking sequence of the yellow, blue, and red phosphor layers in order of increasing distance from the LED. The stacking sequence of the yellow and blue phosphor layers is first determined in such a manner that these layers do not interact with each other. The stacking sequence of the red and yellow phosphor layers and the stacking sequence of the red and blue phosphor layers are determined by the discriminant D. This determination of the stacking sequence suppresses a reduction in the conversion efficiency of the phosphors due to concentration quenching, improving the emission efficiency of the light-emitting device.
    Type: Application
    Filed: March 6, 2009
    Publication date: October 1, 2009
    Applicant: TOYODA GOSEI CO., LTD.
    Inventors: Mitsuhiro Inoue, Kenji Ito, Kazuyohi Tomita, Tetsu Kachi, Takahiro Kozawa, Satoru Kato, Tadashi Ichikawa
  • Publication number: 20080185609
    Abstract: An object of the invention is to prevent migration of silver contained in an electrode of a Group III nitride-based compound semiconductor light-emitting device. An n-type AlxGayIn1-x-yN layer, a light-emitting layer, and a p-type AlxGayIn1-x-yN layer are formed on a dielectric substrate such as a sapphire substrate. After formation of these layers, the n-type AlxGayIn1-x-yN layer is exposed through etching or a similar technique, and an n-electrode is formed on the exposed area. A positive electrode is formed on the p-type layer. In the positive electrode, an ITO light-transmitting electrode layer, a silver alloy reflecting electrode layer, a diffusion-preventing layer in which a Ti layer and a Pt layer are stacked, and a gold thick-film electrode are sequentially stacked on the p-type layer. The reflecting electrode layer made of a silver alloy contains palladium (Pd) and copper (Cu) as additives and also contains oxygen (O).
    Type: Application
    Filed: February 4, 2008
    Publication date: August 7, 2008
    Applicants: KABUSHIKI KAISHA TOYOTA CHUO KENKYUSHO, TOYODA GOSEI CO., LTD.
    Inventors: Takahiro KOZAWA, Kazuyoshi TOMITA, Toshiya UEMURA, Shigemi HORIUCHI
  • Patent number: 7247884
    Abstract: A photo-excited semiconductor layer smaller in band gap energy than a light-emitting layer made of a Group III nitride compound semiconductor is provided between a substrate and the light-emitting layer. The photo-excited semiconductor layer is excited by the light emitted from the light-emitting layer to thereby emit light at a wavelength longer than that of the light emitted from the light-emitting layer.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: July 24, 2007
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Naoki Shibata, Takahiro Kozawa
  • Publication number: 20060273324
    Abstract: The back surface of a semiconductor crystal substrate 102 which has a thickness of about 150 ?m and is made of undoped GaN bulk crystal consists of a polished plane 102a which is flattened through dry-etching and a grinded plane 102b which is formed in a taper shape and is flattened through dry-etching. On about 10 nm in thickness of GaN n-type clad layer (low carrier concentration layer) 104, about 2 nm in thickness of Al0.005In0.045Ga0.95N well layer 51 and about 18 nm in thickness of Al0.12Ga0.88N barrier layer 52 are deposited alternately as an active layer 105 which emits ultraviolet light and has MQW structure comprising 5 layers in total. Before forming a negative electrode (n-electrode c) on the polished plane of the semiconductor substrate a, the polished plane is dry-etched.
    Type: Application
    Filed: July 26, 2004
    Publication date: December 7, 2006
    Inventors: Makoto Asai, Shiro Yamazaki, Takahiro Kozawa, Mitsuhisa Narukawa
  • Patent number: 6891203
    Abstract: According to the invention, a Group III nitride compound semiconductor light-emitting element is provided with a light-emitting layer comprising two layers of different in ratio of AlGaInN composition, and emitting light with an emission peak wavelength in an ultraviolet region and light with an emission peak wavelength in a visible region. The light-emitting element and a fluorescent material excited by light in the ultraviolet region are combined to configure a light emitting device.
    Type: Grant
    Filed: January 4, 2002
    Date of Patent: May 10, 2005
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Takahiro Kozawa, Naoki Shibata
  • Patent number: 6864502
    Abstract: A III group nitride system compound semiconductor light emitting element has a quantum well structure that includes a well layer of AlX1GaY1In1-X1-Y1N, where 0<X1, 0?Y1 and X1+Y1<1 and a barrier layer of AlX2GaY2In1-X2-Y2N, where 0<X2, 0?Y2 and X2+Y2<1. The Al composition (X2) of barrier layer is equal to or smaller than that (X1) of well layer.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: March 8, 2005
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Naoki Shibata, Takahiro Kozawa
  • Publication number: 20040169186
    Abstract: A III group nitride system compound semiconductor light emitting element has a quantum well structure that includes a well layer of AlX1GaY1In1−X1−Y1N, where 0<X1, 0≦Y1 and X1+Y1<1 and a barrier layer of AlX2GaY2In1−X2−Y2N, where 0<X2, 0≦Y2 and X2+Y2<1. The Al composition (X2) of barrier layer is equal to or smaller than that (X1) of well layer.
    Type: Application
    Filed: September 17, 2003
    Publication date: September 2, 2004
    Applicant: Toyoda Gosei Co., Ltd.
    Inventors: Naoki Shibata, Takahiro Kozawa
  • Publication number: 20040061115
    Abstract: According to the invention, a Group III nitride compound semiconductor light-emitting element is provided with a light-emitting layer comprising two layers of different in ratio of AlGaInN composition, and emitting light with an emission peak wavelength in an ultraviolet region and light with an emission peak wavelength in a visible region. The light-emitting element and a fluorescent material excited by light in the ultraviolet region are combined to configure a light emitting device.
    Type: Application
    Filed: July 9, 2003
    Publication date: April 1, 2004
    Inventors: Takahiro Kozawa, Naoki Shibata