Patents by Inventor Hajime Nago

Hajime Nago 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: 20080179623
    Abstract: A semiconductor light emitting element includes: an {0001} n-type semiconductor substrate formed of a III-V semiconductor, which is in a range of 0° to 45° in inclination angle into a <1-100> direction, and which is in a range of 0° to 10° in inclination angle into a <11-20> direction; an n-type layer formed of a III-V semiconductor on the n-type semiconductor substrate; an n-type guide layer formed of a III-V semiconductor above the n-type layer; an active layer formed of a III-V semiconductor above the n-type guide layer; a p-type first guide layer formed of a III-V semiconductor above the active layer; a p-type contact layer formed of a III-V semiconductor above the p-type first guide layer; and an concavo-convex layer formed of a III-V semiconductor between the p-type first guide layer and the p-type contact layer.
    Type: Application
    Filed: September 5, 2007
    Publication date: July 31, 2008
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Koichi TACHIBANA, Hajime Nago, Shinji Saito, Shinya Nunoue, Genichi Hatakoshi
  • Patent number: 7397069
    Abstract: A semiconductor device has an active layer, a first semiconductor layer of first conductive type, an overflow prevention layer disposed between the active layer and the first semiconductor layer, which is doped with impurities of first conductive type and which prevents overflow of electrons or holes, a second semiconductor layer of first conductive type disposed at least one of between the active layer and the overflow prevention layer and between the overflow prevention layer and the first semiconductor layer, and an impurity diffusion prevention layer disposed between the first semiconductor layer and the active layer, which has a band gap smaller than those of the overflow prevention layer, the first semiconductor layer and the second semiconductor layer and which prevents diffusion of impurities of first conductive type.
    Type: Grant
    Filed: August 29, 2006
    Date of Patent: July 8, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichi Tachibana, Chie Hongo, Hajime Nago, Shinya Nunoue
  • Publication number: 20080151957
    Abstract: A semiconductor device has an active layer, a first semiconductor layer of first conductive type, an overflow prevention layer disposed between the active layer and the first semiconductor layer, which is doped with impurities of first conductive type and which prevents overflow of electrons or holes, a second semiconductor layer of first conductive type disposed at least one of between the active layer and the overflow prevention layer and between the overflow prevention layer and the first semiconductor layer, and an impurity diffusion prevention layer disposed between the first semiconductor layer and the active layer, which has a band gap smaller than those of the overflow prevention layer, the first semiconductor layer and the second semiconductor layer and which prevents diffusion of impurities of first conductive type.
    Type: Application
    Filed: February 25, 2008
    Publication date: June 26, 2008
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Koichi Tachibana, Chie Hongo, Hajime Nago, Shinya Nunoue
  • Publication number: 20070096142
    Abstract: A semiconductor device has an active layer, a first semiconductor layer of first conductive type, an overflow prevention layer disposed between the active layer and the first semiconductor layer, which is doped with impurities of first conductive type and which prevents overflow of electrons or holes, a second semiconductor layer of first conductive type disposed at least one of between the active layer and the overflow prevention layer and between the overflow prevention layer and the first semiconductor layer, and an impurity diffusion prevention layer disposed between the first semiconductor layer and the active layer, which has a band gap smaller than those of the overflow prevention layer, the first semiconductor layer and the second semiconductor layer and which prevents diffusion of impurities of first conductive type.
    Type: Application
    Filed: August 29, 2006
    Publication date: May 3, 2007
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Koichi Tachibana, Chie Hongo, Hajime Nago, Shinya Nunoue