Patents by Inventor Takahiko Oohara

Takahiko Oohara 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: 5145793
    Abstract: A method for manufacturing a solar cell which includes at least a first GaAs layer of a first conductivity type and a second GaAs layer of a second conducitivity type sequentially formed on a first main surface of an Si substrate of the first conductivity type, a first electrode formed on a second main surface opposite to the first main surface of the Si substrate and a second electrode formed on the second GaAs layer. The method includes a first step of forming a layer comprising a material having a thermal expansion coefficient smaller than that of Si on the second main surface of the Si substrate at a temperature close to room temperature and a second step of sequentially forming the first and second GaAs layers on the first main surface of the Si substrate.
    Type: Grant
    Filed: April 12, 1991
    Date of Patent: September 8, 1992
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Takahiko Oohara, Yoshiro Ohmachi, Yoshiaki Kadota, Kotaro Mitsui, Nobuyoshi Ogasawara, Takashi Nishimura
  • Patent number: 5131956
    Abstract: A photovoltaic semiconductor device includes a first conductivity type silicon substrate having a first main surface, a first conductivity type compound semiconductor layer disposed on a first, major portion of the first main surface of the silicon substrate, a second conductivity type compound semiconductor layer disposed on the first conductivity type compound semiconductor layer, a first electrode connected to the second conductivity type compound semiconductor layer, a portion of the first electrode being disposed on a second, minor portion of the first main surface of the silicon substrate with an intervening insulating film, and a second electrode disposed on a third, minor portion of the first main surface of the silicon substrate.
    Type: Grant
    Filed: March 28, 1991
    Date of Patent: July 21, 1992
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Nippon Telegraph and Telephone Corporation
    Inventors: Takahiko Oohara, Masaaki Usui, Nobuyoshi Ogasawara, Kotaro Mitsui