Patents by Inventor Yohei Otoki

Yohei Otoki 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: 20230152268
    Abstract: There is provided an electrochemical sensor, comprising: a working electrode; a counter electrode; and a base material supporting the working electrode and the counter electrode, wherein the working electrode is a chip-shaped electrode including a diamond film that causes a redox reaction on its surface when a predetermined voltage is applied in a state where a test sample exists between the working electrode and the counter electrode, and a support that comprises a material other than diamond and supports the diamond film, and the working electrode is mounted on the base material, with the support positioned on the base material side and at least a part of a side surface of the support exposed.
    Type: Application
    Filed: April 15, 2021
    Publication date: May 18, 2023
    Applicant: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Kaori KURIHARA, Yohei OTOKI, Koji NAKAMURA, Yuichi KOIBUCHI, Atsushi SATO
  • Publication number: 20220260516
    Abstract: An electrochemical sensor unit including: a working electrode; and a counter electrode, wherein the working electrode includes a diamond film which generates a redox reaction on a surface when a voltage is applied between the working electrode and the counter electrode, and a support which is formed of a material different from diamond and supports the diamond film, when the working electrode is viewed laterally, in the support, a width of a surface opposite to a surface in contact with the diamond film is smaller than a width of the diamond film, and a liquid test sample is supplied to the working electrode from the diamond film side.
    Type: Application
    Filed: July 15, 2020
    Publication date: August 18, 2022
    Applicant: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Kaori KURIHARA, Yohei OTOKI, Fumimasa HORIKIRI
  • Patent number: 8440549
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: May 14, 2013
    Assignees: Fujitsu Limited, Hitachi Cable Co., Ltd.
    Inventors: Kenji Imanishi, Toshihide Kikkawa, Takeshi Tanaka, Yoshihiko Moriya, Yohei Otoki
  • Patent number: 8264006
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: September 11, 2012
    Assignees: Fujitsu Limited, Hitachi Cable Co., Ltd.
    Inventors: Kenji Imanishi, Toshihide Kikkawa, Takeshi Tanaka, Yoshihiko Moriya, Yohei Otoki
  • Patent number: 8264005
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: September 11, 2012
    Assignee: Fujitsu Limited
    Inventors: Kenji Imanishi, Toshihide Kikkawa, Takeshi Tanaka, Yoshihiko Moriya, Yohei Otoki
  • Publication number: 20120067275
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Application
    Filed: September 20, 2011
    Publication date: March 22, 2012
    Applicants: HITACHI CABLE CO., LTD., FUJITSU LIMITED
    Inventors: Kenji Imanishi, Toshihide Kikkawa, Takeshi Tanaka, Yoshihiko Moriya, Yohei Otoki
  • Patent number: 8044492
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: October 25, 2011
    Assignees: Fujitsu Limited, Hitachi Cable Co., Ltd.
    Inventors: Kenji Imanishi, Toshihide Kikkawa, Takeshi Tanaka, Yoshihiko Moriya, Yohei Otoki
  • Patent number: 7948009
    Abstract: A nitride semiconductor epitaxial wafer includes a growth substrate including a surface for growing a nitride semiconductor thereon, a first structure layer formed on the growth substrate, a dislocation propagation direction changing layer formed on the first structure layer for changing a propagation direction of a dislocation propagated in the first structure layer into a lateral direction, a second structure layer formed on the dislocation propagation direction changing layer, and a buffer layer formed on the second structure layer for changing a propagation direction of a dislocation propagated in the second structure layer.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: May 24, 2011
    Assignee: Hitachi Cable, Ltd.
    Inventors: Yoshihiko Moriya, Takeshi Tanaka, Yohei Otoki, Masae Sahara
  • Publication number: 20100207167
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Application
    Filed: May 3, 2010
    Publication date: August 19, 2010
    Applicants: FUJITSU LIMITED, HITACHI CABLE, LTD.
    Inventors: Kenji IMANISHI, Toshihide KIKKAWA, Takeshi TANAKA, Yoshihiko MORIYA, Yohei OTOKI
  • Publication number: 20100207124
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Application
    Filed: May 3, 2010
    Publication date: August 19, 2010
    Applicants: FUJITSU LIMITED, HITACHI CABLE, LTD.
    Inventors: Kenji IMANISHI, Toshihide KIKKAWA, Takeshi TANAKA, Yoshihiko MORIYA, Yohei OTOKI
  • Publication number: 20090236634
    Abstract: A nitride semiconductor epitaxial wafer includes a growth substrate including a surface for growing a nitride semiconductor thereon, a first structure layer formed on the growth substrate, a dislocation propagation direction changing layer formed on the first structure layer for changing a propagation direction of a dislocation propagated in the first structure layer into a lateral direction, a second structure layer formed on the dislocation propagation direction changing layer, and a buffer layer formed on the second structure layer for changing a propagation direction of a dislocation propagated in the second structure layer.
    Type: Application
    Filed: March 17, 2009
    Publication date: September 24, 2009
    Applicant: Hitachi Cable, Ltd.
    Inventors: Yoshihiko Moriya, Takeshi Tanaka, Yohei Otoki, Masae Sahara
  • Publication number: 20090026499
    Abstract: A semiconductor integrated circuit device having a plurality of semiconductor electronic members including a field effect transistor, intended for suppressing a sidegating effect on the field effect transistor, wherein accumulation of majority carriers of the field effect transistor is suppressed at the interface of heterojunction in the buffering compound semiconductor layer and the interface between the substrate and the buffering compound semiconductor layer in the device isolation region so that the discontinuity of energy forbidden bands of the semiconductors caused at the interfaces does not form a potential barrier upon conduction of the carriers into the substrate, whereby the sidegating effect from the resistor element, etc. placed adjacently to the field effect transistor can be decreased drastically.
    Type: Application
    Filed: January 24, 2008
    Publication date: January 29, 2009
    Inventors: Takeshi Kikawa, Shinichiro Takatani, Tomihisa Yukimoto, Yohei Otoki, Hiroyuki Kamogawa, Tomoyoshi Mishima
  • Publication number: 20080237610
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Application
    Filed: March 31, 2008
    Publication date: October 2, 2008
    Applicants: FUJITSU LIMITED, HITACHI CABLE, LTD.
    Inventors: Kenji IMANISHI, Toshihide KIKKAWA, Takeshi TANAKA, Yoshihiko MORIYA, Yohei OTOKI