Patents Represented by Law Firm 31ydig, Voit & Mayer
  • Heterojunction bipolar transistor
    Patent number: 5073812
    Abstract: A semiconductor device includes an n.sup.+ type InGaAs layer at a surface of the device, a refractory metal emitter electrode making ohmic contact to the n.sup.+ layer without alloying, and an externally accessible base region produced in the neighborhood of the emitter electrode by a diffusion using the emitter electrode and an insulating side wall film as a diffusion mask.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: December 17, 1991
    Assignee: Mitubishi Denki Kabushiki Kaisha
    Inventor: Teruyuki Shimura