Patents by Inventor Makoto Kiyama

Makoto Kiyama 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).

  • Patent number: 11910714
    Abstract: A thermoelectric conversion material contains a matrix composed of a semiconductor and nanoparticles disposed in the matrix, and the nanoparticles have a lattice constant distribution ?d/d of 0.0055 or more.
    Type: Grant
    Filed: August 11, 2021
    Date of Patent: February 20, 2024
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masahiro Adachi, Makoto Kiyama, Yoshiyuki Yamamoto, Ryo Toyoshima
  • Patent number: 11737364
    Abstract: A thermoelectric conversion material includes: a base material that is a semiconductor composed of a base material element; a first additional element that is an element different from the base material element, has a vacant orbital in a d orbital or f orbital located internal to an outermost shell of the first additional element and forms a first additional level in a forbidden band of the base material; and a second additional element that is an element different from both of the base material element and the first additional element and forms a second additional level in the forbidden band of the base material. A difference is 1 between the number of electrons in an outermost shell of the second additional element and the number of electrons in at least one outermost shell of the base material element.
    Type: Grant
    Filed: December 28, 2018
    Date of Patent: August 22, 2023
    Assignees: SUMITOMO ELECTRIC INDUSTRIES, LTD., TOYOTA SCHOOL FOUNDATION
    Inventors: Masahiro Adachi, Kotaro Hirose, Makoto Kiyama, Takashi Matsuura, Yoshiyuki Yamamoto, Tsunehiro Takeuchi, Shunsuke Nishino
  • Patent number: 11611030
    Abstract: A thermoelectric material element includes: a thermoelectric material portion composed of a thermoelectric material that includes a first crystal phase and a second crystal phase during an operation, the second crystal phase being different from the first crystal phase; a first electrode disposed in contact with the thermoelectric material portion; and a second electrode disposed in contact with the thermoelectric material portion and disposed to be separated from the first electrode. During the operation, the thermoelectric material portion includes a first temperature region having a first temperature, and a second temperature region having a second temperature lower than the first temperature of the first temperature region. A ratio of the first crystal phase to the second crystal phase in the first temperature region is larger than a ratio of the first crystal phase to the second crystal phase in the second temperature region.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: March 21, 2023
    Assignees: SUMITOMO ELECTRIC INDUSTRIES, LTD., TOYOTA SCHOOL FOUNDATION
    Inventors: Masahiro Adachi, Makoto Kiyama, Takashi Matsuura, Yoshiyuki Yamamoto, Do-Gyun Byeon, Tsunehiro Takeuchi
  • Patent number: 11462670
    Abstract: A thermoelectric conversion material includes: a base material that is a semiconductor; and an additive element that differs from an element constituting the base material. An additional band formed of the additive element is present within a forbidden band of the base material. A density of states of the additional band has a ratio of greater than or equal to 0.1 relative to a maximum value of a density of states of a valence band adjacent to the forbidden band of the base material.
    Type: Grant
    Filed: August 29, 2017
    Date of Patent: October 4, 2022
    Assignees: Sumitomo Electric Industries, Ltd., Toyota School Foundation
    Inventors: Masahiro Adachi, Makoto Kiyama, Yoshiyuki Yamamoto, Tsunehiro Takeuchi
  • Patent number: 11282997
    Abstract: A plate-shaped thermoelectric conversion material having a first main surface and a second main surface on the opposite side of the first main surface is formed of semiconductor grains that are in contact with one another. The semiconductor grains each include a particle composed of a semiconductor containing an amorphous phase, and an oxidized layer covering the particle. The distance between the first main surface and the second main surface exceeds 0.5 mm.
    Type: Grant
    Filed: April 18, 2018
    Date of Patent: March 22, 2022
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masahiro Adachi, Makoto Kiyama, Yoshiyuki Yamamoto
  • Publication number: 20210384397
    Abstract: A thermoelectric conversion material contains a matrix composed of a semiconductor and nanoparticles disposed in the matrix, and the nanoparticles have a lattice constant distribution ?d/d of 0.0055 or more.
    Type: Application
    Filed: August 11, 2021
    Publication date: December 9, 2021
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masahiro Adachi, Makoto Kiyama, Yoshiyuki Yamamoto, Ryo Toyoshima
  • Patent number: 11139422
    Abstract: A thermoelectric conversion material contains a matrix composed of a semiconductor and nanoparticles disposed in the matrix, and the nanoparticles have a lattice constant distribution ?d/d of 0.0055 or more.
    Type: Grant
    Filed: April 11, 2018
    Date of Patent: October 5, 2021
    Assignee: SUMITOMO ELECTRIC INDUSTRIES. LTD.
    Inventors: Masahiro Adachi, Makoto Kiyama, Yoshiyuki Yamamoto, Ryo Toyoshima
  • Patent number: 11024705
    Abstract: A semi-insulating gallium arsenide crystal substrate has a main surface with a plane orientation of (100) and a diameter of 2R mm, the main surface having a specific resistance with an average value of 5×107 ?·cm or more and with a standard deviation divided by the average value of the specific resistance, or with a coefficient of variation, of 0.50 or less in each of three measurement areas having their centers at distances of 0 mm, 0.5R mm, and (R-17) mm, respectively, from the center of the main surface in the [010] direction.
    Type: Grant
    Filed: September 21, 2017
    Date of Patent: June 1, 2021
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shinya Kawamoto, Makoto Kiyama, Yukio Ishikawa, Katsushi Hashio
  • Publication number: 20210091289
    Abstract: A thermoelectric conversion material includes: a base material that is a semiconductor composed of a base material element; a first additional element that is an element different from the base material element, has a vacant orbital in a d orbital or f orbital located internal to an outermost shell of the first additional element and forms a first additional level in a forbidden band of the base material; and a second additional element that is an element different from both of the base material element and the first additional element and forms a second additional level in the forbidden band of the base material. A difference is 1 between the number of electrons in an outermost shell of the second additional element and the number of electrons in at least one outermost shell of the base material element.
    Type: Application
    Filed: December 28, 2018
    Publication date: March 25, 2021
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., TOYOTA SCHOOL FOUNDATION
    Inventors: Masahiro ADACHI, Kotaro HIROSE, Makoto KIYAMA, Takashi MATSUURA, Yoshiyuki YAMAMOTO, Tsunehiro TAKEUCHI, Shunsuke NISHINO
  • Publication number: 20200403136
    Abstract: A thermoelectric material element includes: a thermoelectric material portion composed of a thermoelectric material that includes a first crystal phase and a second crystal phase during an operation, the second crystal phase being different from the first crystal phase; a first electrode disposed in contact with the thermoelectric material portion; and a second electrode disposed in contact with the thermoelectric material portion and disposed to be separated from the first electrode. During the operation, the thermoelectric material portion includes a first temperature region having a first temperature, and a second temperature region having a second temperature lower than the first temperature of the first temperature region. A ratio of the first crystal phase to the second crystal phase in the first temperature region is larger than a ratio of the first crystal phase to the second crystal phase in the second temperature region.
    Type: Application
    Filed: February 15, 2019
    Publication date: December 24, 2020
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., TOYOTA SCHOOL FOUNDATION
    Inventors: Masahiro ADACHI, Makoto KIYAMA, Takashi MATSUURA, Yoshiyuki YAMAMOTO, Do-Gyun BYEON, Tsunehiro TAKEUCHI
  • Publication number: 20200381509
    Abstract: A semi-insulating gallium arsenide crystal substrate has a main surface with a plane orientation of (100) and a diameter of 2R mm, the main surface having a specific resistance with an average value of 5×107 ?·cm or more and with a standard deviation divided by the average value of the specific resistance, or with a coefficient of variation, of 0.50 or less in each of three measurement areas having their centers at distances of 0 mm, 0.5R mm, and (R-17) mm, respectively, from the center of the main surface in the [010] direction.
    Type: Application
    Filed: September 21, 2017
    Publication date: December 3, 2020
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Shinya KAWAMOTO, Makoto KIYAMA, Yukio ISHIKAWA, Katsushi HASHIO
  • Patent number: 10837124
    Abstract: A gallium nitride substrate has a surface with a diameter of not less than 100 mm, a difference being not less than 0.1 cm?1 and not more than 2 cm?1 between maximum and minimum values of wave numbers at a maximum peak of peaks corresponding to an E2H phonon mode in micro-Raman scattering mapping measurement at each of square regions having sides each having a length of 2 mm, the square regions being located at a total of five locations including a central location and four circumferential edge locations on the surface of the gallium nitride substrate, a difference being not more than 2 cm?1 between maximum and minimum values of the wave numbers at the maximum peak of the peaks corresponding to the E2H phonon mode at all of measurement points in the five locations.
    Type: Grant
    Filed: September 16, 2019
    Date of Patent: November 17, 2020
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Makoto Kiyama, Ryu Hirota, Seiji Nakahata
  • Publication number: 20200203591
    Abstract: A thermoelectric conversion material contains a matrix composed of a semiconductor and nanoparticles disposed in the matrix, and the nanoparticles have a lattice constant distribution ?d/d of 0.0055 or more.
    Type: Application
    Filed: April 11, 2018
    Publication date: June 25, 2020
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Masahiro ADACHI, Makoto KIYAMA, Yoshiyuki YAMAMOTO, Ryo TOYOSHIMA
  • Publication number: 20200105992
    Abstract: A plate-shaped thermoelectric conversion material having a first main surface and a second main surface on the opposite side of the first main surface is formed of semiconductor grains that are in contact with one another. The semiconductor grains each include a particle composed of a semiconductor containing an amorphous phase, and an oxidized layer covering the particle. The distance between the first main surface and the second main surface exceeds 0.5 mm.
    Type: Application
    Filed: April 18, 2018
    Publication date: April 2, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masahiro ADACHI, Makoto KIYAMA, Yoshiyuki YAMAMOTO
  • Publication number: 20200032419
    Abstract: A gallium nitride substrate has a surface with a diameter of not less than 100 mm, a difference being not less than 0.1 cm?1 and not more than 2 cm?1 between maximum and minimum values of wave numbers at a maximum peak of peaks corresponding to an E2H phonon mode in micro-Raman scattering mapping measurement at each of square regions having sides each having a length of 2 mm, the square regions being located at a total of five locations including a central location and four circumferential edge locations on the surface of the gallium nitride substrate, a difference being not more than 2 cm?1 between maximum and minimum values of the wave numbers at the maximum peak of the peaks corresponding to the E2H phonon mode at all of measurement points in the five locations.
    Type: Application
    Filed: September 16, 2019
    Publication date: January 30, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Makoto KIYAMA, Ryu HIROTA, Seiji NAKAHATA
  • Patent number: 10458043
    Abstract: A gallium nitride substrate has a surface with a diameter of not less than 100 mm, a difference being not less than 0.1 cm?1 and not more than 2 cm?1 between maximum and minimum values of wave numbers at a maximum peak of peaks corresponding to an E2H phonon mode in micro-Raman scattering mapping measurement at each of square regions having sides each having a length of 2 mm, the square regions being located at a total of five locations including a central location and four circumferential edge locations on the surface of the gallium nitride substrate, a difference being not more than 2 cm?1 between maximum and minimum values of the wave numbers at the maximum peak of the peaks corresponding to the E2H phonon mode at all of measurement points in the five locations.
    Type: Grant
    Filed: April 10, 2015
    Date of Patent: October 29, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Makoto Kiyama, Ryu Hirota, Seiji Nakahata
  • Patent number: 10443151
    Abstract: There is provided a gallium nitride substrate having a C plane as a surface with a diameter of not less than 100 mm, the gallium nitride substrate including first regions and second regions having different average values of band-edge emission intensities in a micro photoluminescence mapping at 25° C. in a square region located in the C plane and having sides each having a length of 2 mm, an average value Ibe1a of the band-edge emission intensities of the first regions and an average value Ibe2a of the band-edge emission intensities of the second regions satisfying the following relational expressions (I) and (II): Ibe1a>Ibe2a . . . (I) and 2.1?Ibe1a/Ibe2a?9.4 . . . (II).
    Type: Grant
    Filed: April 20, 2018
    Date of Patent: October 15, 2019
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Makoto Kiyama, Ryu Hirota, Seiji Nakahata
  • Publication number: 20190214538
    Abstract: A thermoelectric conversion material includes: a base material that is a semiconductor; and an additive element that differs from an element constituting the base material. An additional band formed of the additive element is present within a forbidden band of the base material. A density of states of the additional band has a ratio of greater than or equal to 0.1 relative to a maximum value of a density of states of a valence band adjacent to the forbidden band of the base material.
    Type: Application
    Filed: August 29, 2017
    Publication date: July 11, 2019
    Applicants: Sumitomo Electric Industries, Ltd., Toyota School Foundation
    Inventors: Masahiro ADACHI, Makoto KIYAMA, Yoshiyuki YAMAMOTO, Tsunehiro TAKEUCHI
  • Publication number: 20180237946
    Abstract: There is provided a gallium nitride substrate having a C plane as a surface with a diameter of not less than 100 mm, the gallium nitride substrate including first regions and second regions having different average values of band-edge emission intensities in a micro photoluminescence mapping at 25° C. in a square region located in the C plane and having sides each having a length of 2 mm, an average value Ibe1a of the band-edge emission intensities of the first regions and an average value Ibe2a of the band-edge emission intensities of the second regions satisfying the following relational expressions (I) and (II): Ibe1a>Ibe2a . . . (I) and 2.1?Ibe1a/Ibe2a?9.4 . . . (II).
    Type: Application
    Filed: April 20, 2018
    Publication date: August 23, 2018
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Makoto KIYAMA, Ryu HIROTA, Seiji NAKAHATA
  • Patent number: 10006147
    Abstract: There is provided a gallium nitride substrate having a C plane as a surface with a diameter of not less than 100 mm, the gallium nitride substrate including first regions and second regions having different average values of band-edge emission intensities in a micro photoluminescence mapping at 25° C. in a square region located in the C plane and having sides each having a length of 2 mm, an average value Ibe1a of the band-edge emission intensities of the first regions and an average value Ibe2a of the band-edge emission intensities of the second regions satisfying the following relational expressions (I) and (II): Ibe1a>Ibe2a??(I) and 2.1?Ibe1a/Ibe2a?9.4??(II).
    Type: Grant
    Filed: April 16, 2015
    Date of Patent: June 26, 2018
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Makoto Kiyama, Ryu Hirota, Seiji Nakahata