Patents by Inventor Daiki Wakimoto

Daiki Wakimoto 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: 11043602
    Abstract: Provided is a Schottky barrier diode which is configured from a Ga2O3-based semiconductor, and has a lower rising voltage than a conventional one. In one embodiment, the Schottky barrier diode 1 is provided which has: a semiconductor layer 10 configured from a Ga2O3-based single crystal; an anode electrode 11 which forms a Schottky junction with the semiconductor layer 10, and has a portion which contacts the semiconductor layer 10 and is composed of Fe or Cu; and a cathode electrode 12.
    Type: Grant
    Filed: February 19, 2018
    Date of Patent: June 22, 2021
    Assignees: Tamura Corporation, Novel Crystal Technology, Inc.
    Inventors: Kohei Sasaki, Daiki Wakimoto, Yuki Koishikawa, Quang Tu Thieu
  • Publication number: 20210151611
    Abstract: A Schottky barrier diode includes a semiconductor layer including a Ga2O3-based single crystal, an anode electrode that forms a Schottky junction with the semiconductor layer and is configured so that a portion in contact with the semiconductor layer includes Mo or W, and a cathode electrode. A turn-on voltage thereof is not less than 0.3 V and not more than 0.5 V.
    Type: Application
    Filed: June 12, 2018
    Publication date: May 20, 2021
    Applicants: TAMURA CORPORATION, Novel Crystal Technology, Inc.
    Inventors: Kohei SASAKI, Daiki WAKIMOTO, Yuki KOISHIKAWA, Quang Tu THIEU
  • Patent number: 11011653
    Abstract: Provided is a Schottky barrier diode which is configured from a Ga2O3-based semiconductor, and has a lower rising voltage than a conventional one. In one embodiment, the Schottky barrier diode 1 is provided which has: a semiconductor layer 10 configured from a Ga2O3-based single crystal; an anode electrode 11 which forms a Schottky junction with the semiconductor layer 10, and has a portion which contacts the semiconductor layer 10 and is composed of Fe or Cu; and a cathode electrode 12.
    Type: Grant
    Filed: February 19, 2018
    Date of Patent: May 18, 2021
    Assignees: Tamura Corporation, Novel Crystal Technology, Inc.
    Inventors: Kohei Sasaki, Daiki Wakimoto, Yuki Koishikawa, Quang Tu Thieu
  • Publication number: 20200144377
    Abstract: A Ga2O3-based semiconductor device includes a Ga2O3-based crystal layer including a donor, and an N-doped region formed in at least a part of the Ga2O3-based crystal layer.
    Type: Application
    Filed: April 26, 2018
    Publication date: May 7, 2020
    Applicants: NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY, TAMURA CORPORATION, NOVEL CRYSTAL TECHNOLOGY, INC.
    Inventors: Masataka HIGASHIWAKI, Yoshiaki NAKATA, Takafumi KAMIMURA, Man Hoi WONG, Kohei SASAKI, Daiki WAKIMOTO
  • Publication number: 20190363197
    Abstract: Provided is a Schottky barrier diode which is configured from a Ga2O3-based semiconductor, and has a lower rising voltage than a conventional one. In one embodiment, the Schottky barrier diode 1 is provided which has: a semiconductor layer 10 configured from a Ga2O3-based single crystal; an anode electrode 11 which forms a Schottky junction with the semiconductor layer 10, and has a portion which contacts the semiconductor layer 10 and is composed of Fe or Cu; and a cathode electrode 12.
    Type: Application
    Filed: February 19, 2018
    Publication date: November 28, 2019
    Applicants: TAMURA CORPORATION, NOVEL CRYSTAL TECHNOLOGY, INC.
    Inventors: Kohei SASAKI, Daiki WAKIMOTO, Yuki KOISHIKAWA, Quang Tu THIEU
  • Patent number: 10358742
    Abstract: A method of growing a conductive Ga2O3-based crystal film by MBE includes producing a Ga vapor and a Si-containing vapor and supplying the vapors as molecular beams onto a surface of a Ga2O3-based crystal substrate so as to grow the Ga2O3-based crystal film. The Ga2O3-based crystal film includes a Si-containing Ga2O3-based single crystal film. The Si-containing vapor is produced by heating Si or a Si compound and Ga while allowing the Si or a Si compound to contact with the Ga.
    Type: Grant
    Filed: June 2, 2017
    Date of Patent: July 23, 2019
    Assignees: TAMURA CORPORATION, Novel Crystal Technology, Inc.
    Inventors: Kohei Sasaki, Daiki Wakimoto
  • Patent number: 9926646
    Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105 /cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.
    Type: Grant
    Filed: October 9, 2013
    Date of Patent: March 27, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Shinya Watanabe, Daiki Wakimoto, Kazuyuki Iizuka, Kimiyoshi Koshi, Takekazu Masui
  • Patent number: 9903045
    Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105 /cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.
    Type: Grant
    Filed: October 9, 2013
    Date of Patent: February 27, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Shinya Watanabe, Daiki Wakimoto, Kazuyuki Iizuka, Kimiyoshi Koshi, Takekazu Masui
  • Publication number: 20170350037
    Abstract: A method of growing a conductive Ga2O3-based crystal film by MBE includes producing a Ga vapor and a Si-containing vapor and supplying the vapors as molecular beams onto a surface of a Ga2O3-based crystal substrate so as to grow the Ga2O3-based crystal film. The Ga2O3-based crystal film includes a Si-containing Ga2O3-based single crystal film. The Si-containing vapor is produced by heating Si or a Si compound and Ga while allowing the Si or a Si compound to contact with the Ga.
    Type: Application
    Filed: June 2, 2017
    Publication date: December 7, 2017
    Applicants: TAMURA CORPORATION, Novel Crystal Techonology, Inc.
    Inventors: Kohei SASAKI, Daiki WAKIMOTO
  • Patent number: 9349915
    Abstract: A ?-Ga2O3-based single crystal substrate includes a ?-Ga2O3-based single crystal. The ?-Ga2O3-based single crystal includes a full width at half maximum of an x-ray rocking curve of less than 75 seconds.
    Type: Grant
    Filed: February 26, 2015
    Date of Patent: May 24, 2016
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi Koshi, Shinya Watanabe, Masaru Takizawa, Yu Yamaoka, Daiki Wakimoto, Makoto Watanabe
  • Publication number: 20150308012
    Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105/cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.
    Type: Application
    Filed: October 9, 2013
    Publication date: October 29, 2015
    Inventors: Shinya WATANABE, Daiki WAKIMOTO, Kazuyuki IIZUKA, Kimiyoshi KOSHI, Takekazu MASUI
  • Publication number: 20150249185
    Abstract: A ?-Ga2O3-based single crystal substrate includes a ?-Ga2O3-based single crystal. The ?-Ga2O3-based single crystal includes a full width at half maximum of an x-ray rocking curve of less than 75 seconds.
    Type: Application
    Filed: February 26, 2015
    Publication date: September 3, 2015
    Inventors: Kimiyoshi KOSHI, Shinya Watanabe, Masaru Takizawa, Yu Yamaoka, Daiki Wakimoto, Makoto Watanabe
  • Publication number: 20150155356
    Abstract: Provided is a semiconductor laminate structure including a Ga2O3 substrate and a nitride semiconductor layer with high crystal quality on the Ga2O3 substrate, and also provided is a semiconductor element including this semiconductor laminate structure. In one embodiment, this semiconductor laminate structure includes a ?-Ga2O3 substrate including ?-Ga2O3 crystal and a principal surface inclined from a (?201) surface to a [102] direction nd a nitride semiconductor layer including AlxGayInzN (0?x?1, 0?y?1, 0?z?1, x+y+z=1) crystal formed by epitaxial crystal growth on the principal surface of the ?-Ga2O3 substrate.
    Type: Application
    Filed: May 27, 2013
    Publication date: June 4, 2015
    Applicants: TAMURA CORPORATIO9N, KOHA CO., LTD
    Inventors: Kazuyuki Iizuka, Shinya Watanabe, Kimiyoshi Koshi, Daiki Wakimoto, Yoshihiro Yamashita, Shinkuro Sato