Patents Examined by Lang Pham
  • Method of making a heterojunction bipolar transistor
    Patent number: 5212103
    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 diffusion using the emitter electrode and an insulating side wall film as a diffusion mask.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: May 18, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Teruyuki Shimura