Patents by Inventor Tatsuhiro Hirata

Tatsuhiro Hirata 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: 8223814
    Abstract: The present invention provides a semiconductor laser realizing reduced possibility that a wiring layer disposed in the air is broken even under severe environment of a large temperature difference. A trench is provided between adjacent ridges, and a wiring layer electrically connecting an upper electrode and a pad electrode is disposed in the air at least above the trench. The wiring layer in a portion above the trench has a flat shape or a concave shape which dents toward the trench. With the configuration, accumulation of strains in the wiring layer when the wiring layer repeats expansion and shrink under severe environment of a large temperature difference is suppressed.
    Type: Grant
    Filed: September 23, 2010
    Date of Patent: July 17, 2012
    Assignee: Sony Corporation
    Inventors: Hisayoshi Kuramochi, Tomonori Hino, Tatsuhiro Hirata, Yuta Yoshida
  • Publication number: 20110075693
    Abstract: The present invention provides a semiconductor laser realizing reduced possibility that a wiring layer disposed in the air is broken even under severe environment of a large temperature difference. A trench is provided between adjacent ridges, and a wiring layer electrically connecting an upper electrode and a pad electrode is disposed in the air at least above the trench. The wiring layer in a portion above the trench has a flat shape or a concave shape which dents toward the trench. With the configuration, accumulation of strains in the wiring layer when the wiring layer repeats expansion and shrink under severe environment of a large temperature difference is suppressed.
    Type: Application
    Filed: September 23, 2010
    Publication date: March 31, 2011
    Applicant: SONY CORPORATION
    Inventors: Hisayoshi Kuramochi, Tomonori Hino, Tatsuhiro Hirata, Yuta Yoshida
  • Publication number: 20030134491
    Abstract: In a vapor-phase growth method in which a silicon-germanium mixed crystal layer is deposited on a semiconductor substrate, the vapor-phase growth method comprises a first step of introducing silicon raw material gas into a reaction furnace in such a manner that a silicon raw material gas partial pressure increases in proportion to a time to thereby deposit a first semiconductor layer of a silicon layer on the semiconductor substrate under reduced pressure, a second step of introducing silicon raw material gas and germanium raw material gas into the reaction furnace in such a manner that a desired germanium concentration may be obtained to thereby deposit a second semiconductor layer of a silicon-germanium mixed crystal layer on the first semiconductor layer under reduced pressure and a third step of introducing silicon raw material gas into the reaction furnace under reduced pressure to thereby deposit a third semiconductor layer of a silicon layer on the second semiconductor layer.
    Type: Application
    Filed: December 2, 2002
    Publication date: July 17, 2003
    Inventors: Hideo Yamagata, Takeyoshi Koumoto, Kenji Atsuumi, Yoichi Negoro, Tatsuhiro Hirata, Takashi Noguchi