Patents by Inventor Choho Yamagishi

Choho Yamagishi 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).

  • Method of forming ohmic contact on GaAs by Ge film and implanting impurity ions therethrough
    Patent number: 4540446
    Abstract: A method of manufacturing a GaAs compound semiconductor device is disclosed. The method comprises steps of applying a Ge film on an n+ region for forming ohmic electrode thereon, injecting impurity ion into the Ge film with high concentration, applying metal of high melting point overall surface of the semiconductor body to an annealing treatment after final ion implantation step.
    Type: Grant
    Filed: April 20, 1984
    Date of Patent: September 10, 1985
    Assignee: OKI Electric Industry Co., Ltd.
    Inventors: Toshio Nonaka, Hiroshi Nakamura, Choho Yamagishi