Patents by Inventor Kenichi Ohto

Kenichi Ohto 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 for manufacturing semiconductor device
    Patent number: 6939777
    Abstract: An alignment mark section on a semiconductor substrate has two grooves which are filled with silicon oxide. The surface of the portion of the semiconductor substrate sandwiched by these grooves is lower than other portions of the semiconductor substrate to produce a step having a predetermined depth in the alignment mark section.
    Type: Grant
    Filed: June 9, 2004
    Date of Patent: September 6, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Kenichi Ohto, Takashi Terauchi
  • Method for manufacturing semiconductor device
    Publication number: 20050101107
    Abstract: An alignment mark section on a semiconductor substrate has two grooves which are filled with silicon oxide. The surface of the portion of the semiconductor substrate sandwiched by these grooves is lower than other portions of the semiconductor substrate to produce a step having a predetermined depth in the alignment mark section.
    Type: Application
    Filed: June 9, 2004
    Publication date: May 12, 2005
    Applicant: Renesas Technology Corp.
    Inventors: Kenichi Ohto, Takashi Terauchi
  • MOSFET with graded gate oxide layer
    Patent number: 6812536
    Abstract: A smile oxide film, serving as a gate oxide film, is formed under a three-layer poly-metal gate consisting of a doped polysilicon layer, a tungsten layer, and a SiON layer. The smile oxide film has a first region located beneath an edge of the poly-metal gate and a second region located beneath a central portion of the poly-metal gate. A film thickness of the first region is larger than a film thickness of the second region. An anti-oxidizing film, having a small oxygen diffusion rate compared with the polysilicon layer, entirely covers the poly-metal gate without exposing.
    Type: Grant
    Filed: March 10, 2003
    Date of Patent: November 2, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Shuichi Ueno, Yukio Nishida, Hiroshi Umeda, Kenichi Ohto, Takashi Terauchi, Shigeru Shiratake, Akinori Kinugasa
  • Semiconductor device
    Publication number: 20040046219
    Abstract: A smile oxide film, serving as a gate oxide film, is formed under a three-layer poly-metal gate consisting of a doped polysilicon layer, a tungsten layer, and a SiON layer. The smile oxide film has a first region located beneath an edge of the poly-metal gate and a second region located beneath a central portion of the poly-metal gate. A film thickness of the first region is larger than a film thickness of the second region. An anti-oxidizing film, having a small oxygen diffusion rate compared with the polysilicon layer, entirely covers the poly-metal gate without exposing.
    Type: Application
    Filed: March 10, 2003
    Publication date: March 11, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Shuichi Ueno, Yukio Nishida, Hiroshi Umeda, Kenichi Ohto, Takashi Terauchi, Shigeru Shiratake, Akinori Kinugasa