Patents by Inventor Tadashi Komatsubara

Tadashi Komatsubara 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: 4706101
    Abstract: A light emitting diode is disclosed which includes an N-GaAs substrate, a double hetero-junction structure obtained by forming an N-GaAlAs clad layer, a P-GaAs active layer and a P-GaAlAs clad layer on the substrate in that order, and a current narrowing structure obtained by selectively forming a contact metal on the P-GaAlAs clad layer in the double hetero-junction structure with the contact metal formed around the contact metal. In the light emitting diode so manufactured, the double hetero-junction structure is formed by a metal organic vapor deposition method. The N-GaAlAs clad layer is of a three-layer structure with one layer of a narrower forbidden band width sandwiched between the remaining two layers of a wider forbidden band width.
    Type: Grant
    Filed: August 20, 1985
    Date of Patent: November 10, 1987
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Nakamura, Masaki Okajima, Tadashi Komatsubara, Tetsuo Sadamasa, Koichi Nitta
  • Patent number: 4625223
    Abstract: A double heterostructure light-emitting semi-conductor device includes a p-GaAs substrate having a first electrode formed on one surface and a current confining layer on the other surface; a confined current conduction layer; and a light-emitting layer structure formed on the current confining layer and the confined current conduction layer. A capping layer of GaAs having a second electrode is formed on the light-emitting layer structure. A light exit window layer for exiting the emitted light is constructed by a thin film of the capping layer.
    Type: Grant
    Filed: February 14, 1985
    Date of Patent: November 25, 1986
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadashi Komatsubara, Tetsuo Sadamasa