Patents by Inventor Masashi Matsushita

Masashi Matsushita 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 with a silicon carbide substrate and ohmic metal layer
    Patent number: 7262434
    Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicide formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such as molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: August 28, 2007
    Assignee: Rohm Co., Ltd.
    Inventors: Yuji Okamura, Masashi Matsushita
  • Semiconductor Device and method of manufacturing the same
    Publication number: 20060234501
    Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicate formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such a s molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.
    Type: Application
    Filed: June 14, 2006
    Publication date: October 19, 2006
    Inventors: Yuji Okamura, Masashi Matsushita
  • Semiconductor device and method of manufacturing the same
    Publication number: 20050145971
    Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicate formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such as molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.
    Type: Application
    Filed: February 8, 2005
    Publication date: July 7, 2005
    Inventors: Yuji Okamura, Masashi Matsushita
  • Semiconductor device and method of manufacturing the same
    Publication number: 20030183895
    Abstract: A semiconductor device provided with a silicon carbide semiconductor substrate, and an ohmic metal layer joined to one surface of the silicon carbide semiconductor substrate in an ohmic contact and composed of a metal material whose silicate formation free energy and carbide formation free energy respectively take negative values. The ohmic metal layer is composed of, for example, a metal material such as molybdenum, titanium, chromium, manganese, zirconium, tantalum, or tungsten.
    Type: Application
    Filed: March 27, 2003
    Publication date: October 2, 2003
    Inventors: Yuji Okamura, Masashi Matsushita
  • BIPOLAR TRANSISTOR AND METHOD OF MANUFACTURING THE SAME
    Publication number: 20030127707
    Abstract: A discrete bipolar transistor for use in high frequency circuits is disclosed, in which a base electrode is formed in a base region through contact holes formed in a thermal oxide film without forming a CVD oxide film on the thermal oxide film, and an emitter contact layer composed of polysilicon and an emitter electrode are formed on an emitter region. The wide diffusion of dopant that occurs during CVD oxide film annealing can be prevented, and a shallow base region can be formed.
    Type: Application
    Filed: January 9, 2003
    Publication date: July 10, 2003
    Applicant: Rohm Co., Ltd.
    Inventors: Masashi Matsushita , Takayuki Kito