Patents by Inventor Toshio Chaki

Toshio Chaki 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).

  • Semiconductor device
    Patent number: 6441406
    Abstract: In order that the threshold value of a cell separated from an emitter wire bonding portion (W1, W2) be larger than that of a cell immediately below the emitter wire bonding portion, the area of a diffusion layer (8a) of a cell separated from the wire bonding portion is made larger than that of a diffusion layer (8) for connecting an emitter electrode (2) and a base region (7) in a cell immediately below the wire bonding portion. This allows a hole current to be discharged outside via an emitter wire within a short time period, without adversely affecting the operating characteristics and the steady loss, in a position where this hole current readily remains upon turn-off in a conventional IGBT. This shortens the fall time and reduces the switching loss.
    Type: Grant
    Filed: October 19, 2001
    Date of Patent: August 27, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidetoshi Nakanishi, Masakazu Kobayashi, Toshio Chaki
  • Semiconductor device
    Publication number: 20020089015
    Abstract: In order that the threshold value of a cell separated from an emitter wire bonding portion (W1, W2) be larger than that of a cell immediately below the emitter wire bonding portion, the area of a diffusion layer (8a) of a cell separated from the wire bonding portion is made larger than that of a diffusion layer (8) for connecting an emitter electrode (2) and a base region (7) in a cell immediately below the wire bonding portion. This allows a hole current to be discharged outside via an emitter wire within a short time period, without adversely affecting the operating characteristics and the steady loss, in a position where this hole current readily remains upon turn-off in a conventional IGBT. This shortens the fall time and reduces the switching loss.
    Type: Application
    Filed: October 19, 2001
    Publication date: July 11, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hidetoshi Nakanishi, Masakazu Kobayashi, Toshio Chaki