Patents by Inventor Weitao Cheng

Weitao Cheng 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).

  • Patent number: 10224322
    Abstract: A semiconductor device includes a diode provided with: a drift layer being a first conductivity type; a cathode region being provided in a back face side of the drift layer and being the first conductivity type; a second conductivity type region provided in a surface layer part of the drift layer; multiple trenches dividing the second conductivity type region into pieces by being provided deeper than the second conductivity type region, and configuring an anode region; a gate insulation film provided in a surface of the trench; a gate electrode provided in a surface of the gate insulation film; an upper electrode electrically connected with the anode region; and a lower electrode electrically connected with the cathode region. A width between the trenches is narrowest in the drift layer is defined as a mesa width. The mesa width is set to be equal to or greater than 0.3 ?m.
    Type: Grant
    Filed: July 22, 2016
    Date of Patent: March 5, 2019
    Assignee: DENSO CORPORATION
    Inventors: Weitao Cheng, Shigeki Takahashi, Masakiyo Sumitomo
  • Publication number: 20180151558
    Abstract: A semiconductor device includes a diode provided with: a drift layer being a first conductivity type; a cathode region being provided in a back face side of the drift layer and being the first conductivity type; a second conductivity type region provided in a surface layer part of the drift layer; multiple trenches dividing the second conductivity type region into pieces by being provided deeper than the second conductivity type region, and configuring an anode region; a gate insulation film provided in a surface of the trench; a gate electrode provided in a surface of the gate insulation film; an upper electrode electrically connected with the anode region; and a lower electrode electrically connected with the cathode region. A width between the trenches is narrowest in the drift layer is defined as a mesa width. The mesa width is set to be equal to or greater than 0.3 ?m.
    Type: Application
    Filed: July 22, 2016
    Publication date: May 31, 2018
    Inventors: Weitao CHENG, Shigeki TAKAHASHI, Masakiyo SUMITOMO
  • Patent number: 9721945
    Abstract: A semiconductor device includes: an IGBT section including a vertical IGBT; and a diode section arranged along the IGBT section and including a diode. The diode section includes a hole injection reduction layer having a first conductivity type and arranged in an upper layer portion of a drift layer, extending to a depth deeper than an anode region constituted by a second conductivity type region in the diode section, having an impurity concentration lower than an impurity concentration of the anode region and higher than an impurity concentration of the drift layer.
    Type: Grant
    Filed: December 16, 2014
    Date of Patent: August 1, 2017
    Assignee: DENSO CORPORATION
    Inventors: Weitao Cheng, Shigeki Takahashi
  • Publication number: 20170025410
    Abstract: A semiconductor device includes: an IGBT section including a vertical IGBT; and a diode section arranged along the IGBT section and including a diode. The diode section includes a hole injection reduction layer having a first conductivity type and arranged in an upper layer portion of a drift layer, extending to a depth deeper than an anode region constituted by a second conductivity type region in the diode section, having an impurity concentration lower than an impurity concentration of the anode region and higher than an impurity concentration of the drift layer.
    Type: Application
    Filed: December 16, 2014
    Publication date: January 26, 2017
    Inventors: Weitao CHENG, Shigeki TAKAHASHI
  • Publication number: 20150008478
    Abstract: A manufacturing method of a semiconductor device includes applying at least one of a particle ray and a radial ray to a surface of a semiconductor substrate on which a transistor including a gate insulation film and a gate electrode has been formed adjacent to the surface, and annealing the semiconductor substrate for recovering a crystal defect contained in the gate insulation film and the gate electrode, after the applying. Further, the manufacturing method includes pre-annealing for reducing a content of a hydrogen molecule and a water molecule contained in the gate insulation film and the gate electrode to a predetermined concentration, before the applying. In the semiconductor device manufactured by this method, a concentration of thermally stable defect existing in the gate insulation film is reduced to a predetermined concentration.
    Type: Application
    Filed: January 22, 2013
    Publication date: January 8, 2015
    Inventors: Weitao Cheng, Shinji Amano, Yoshifumi Okabe, Tomofusa Shiga
  • Publication number: 20090250755
    Abstract: A transistor capable of adjusting a threshold value is obtained by adjusting an impurity concentration of a silicon substrate supporting an SOI layer and by controlling a thickness of a buried insulating layer formed on a surface of the silicon substrate in contact with the SOI layer.
    Type: Application
    Filed: June 21, 2007
    Publication date: October 8, 2009
    Inventors: Tadahiro Ohmi, Akinobu Teramoto, Weitao Cheng