Patents by Inventor Tuyoshi Tanaka

Tuyoshi Tanaka 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).

  • Compound semiconductor device and method for fabricating the same
    Patent number: 6797996
    Abstract: A compound semiconductor device includes an emitter layer, a base layer which is in contact with the emitter layer and formed of a first compound semiconductor, a collector layer which is in contact with the base layer and formed of a second compound semiconductor having a wider bandgap than that of the first compound semiconductor. In the device, a delta doped layer having a higher concentration of an impurity than that of the collector layer is formed at the heterojunction interface between the collector layer and the base layer or in a region of the collector layer located at about 10 nm or less from the heterojunction interface with the base layer.
    Type: Grant
    Filed: May 27, 2003
    Date of Patent: September 28, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masahiro Hikita, Manabu Yanagihara, Tuyoshi Tanaka