Patents by Inventor Ryouichi Takeuchi

Ryouichi Takeuchi 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: 20060163603
    Abstract: A double hetero structure light-emitting diode device includes an active layer (6), a positive-electrode-side cladding layer, a negative-electrode-side cladding layer (4), a window layer (9) and an undoped AlInP layer. The positive-electrode-side cladding layer includes an undoped AlInP layer (7) grown to have a thickness of 0.5 ?m and an intermediate layer (8) doped to assume p-type conductivity and having an intermediate energy band gap value between that of the undoped AlInP layer and that of the window layer. The window layer on the intermediate layer is a GaP layer grown at 730° C. or higher and at a growth rate of 7.8 ?m/hour or more in the presence of Ze serving as a dopant. The negative-electrode-side cladding layer is provided with an undoped AlInP layer (5) having a thickness of 0.1 ?m or more.
    Type: Application
    Filed: February 9, 2004
    Publication date: July 27, 2006
    Inventors: Ryouichi Takeuchi, Keiichi Matsuzawa, Junichi Yamazaki
  • Patent number: 6677615
    Abstract: A semiconductor light-emitting device includes a semiconductor substrate that has a rear surface formed with a first electrode, a semiconductor layer that includes a light-emitting portion and is formed on the semiconductor substrate, a plurality of dispersed electrodes that are individually formed on a part of the surface of the semiconductor layer to make ohmic contact with the semiconductor layer, a transparent conductive film that covers the surface of the semiconductor layer and the dispersed electrodes to electrically conduct with the dispersed electrodes, and a pad electrode that is formed on a part of the surface of the transparent conductive film to electrically conduct with the transparent conductive film.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: January 13, 2004
    Assignee: Showa Denko K.K.
    Inventors: Ryouichi Takeuchi, Kazuhiro Mitani, Wataru Nabekura, Takashi Udagawa, Takaharu Hoshina
  • Publication number: 20030052323
    Abstract: A semiconductor light-emitting device includes a semiconductor substrate that has a rear surface formed with a first electrode, a semiconductor layer that includes a light-emitting portion and is formed on the semiconductor substrate, a plurality of dispersed electrodes that are individually formed on a part of the surface of the semiconductor layer to make ohmic contact with the semiconductor layer, a transparent conductive film that covers the surface of the semiconductor layer and the dispersed electrodes to electrically conduct with the dispersed electrodes, and a pad electrode that is formed on a part of the surface of the transparent conductive film to electrically conduct with the transparent conductive film.
    Type: Application
    Filed: October 7, 2002
    Publication date: March 20, 2003
    Applicant: SHOWA DENKO K.K.
    Inventors: Ryouichi Takeuchi, Kazuhiro Mitani, Wataru Nabekura, Takashi Udagawa, Takaharu Hoshina
  • Patent number: 6512248
    Abstract: A semiconductor light-emitting device includes a semiconductor substrate that has a rear surface formed with a first electrode, a semiconductor layer that includes a light-emitting portion and is formed on the semiconductor substrate, a plurality of dispersed electrodes that are individually formed on a part of the surface of the semiconductor layer to make ohmic contact with the semiconductor layer, a transparent conductive film that covers the surface of the semiconductor layer and the dispersed electrodes to electrically conduct with the dispersed electrodes, and a pad electrode that is formed on a part of the surface of the transparent conductive film to electrically conduct with the transparent conductive film.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: January 28, 2003
    Assignee: Showa Denko K.K.
    Inventors: Ryouichi Takeuchi, Kazuhiro Mitani, Wataru Nabekura, Takashi Udagawa, Takaharu Hoshina
  • Patent number: 6346719
    Abstract: An object of the present invention is to provide a high brightness n-side-up type AlGaInP light-emitting device with a simple structure. An n-type upper cladding layer is constructed by superimposing three n-type AlGaInP layers with different electron concentrations. The relationship between the electron concentrations of the three n-type AlGaInP layers is n3>n1>n2.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: February 12, 2002
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Takashi Udagawa, Toshiki Yoshiuji, Ryouichi Takeuchi