Patents by Inventor Toyomasa Koda

Toyomasa Koda 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: 5299091
    Abstract: A packaged semiconductor device has, according to one embodiment of the present invention, a semiconductor pellet having an electronic circuit therein and electrode pads formed on a principal surface of the pellet, a plurality of electrical connection bumps provided on the electrode pads, a plurality of heat dissipation bumps provided at the principal surface of the pellet and electrically insulated from the electronic circuit and the electrode pads, electrical connection leads for the electronic circuit, heat dissipators for the electronic circuit and a packaging material for sealing pellet, the electrical connection bumps, the heat dissipation bumps and parts of the electrical connection leads and the heat dissipator. One or more of the heat dissipation bumps are arranged relatively nearer to the electronic circuit than the electrical connection bumps for thermal coupling to the electronic circuit.
    Type: Grant
    Filed: March 19, 1992
    Date of Patent: March 29, 1994
    Assignees: Hitachi, Ltd., Hitachi Tohbu Semiconductor, Ltd.
    Inventors: Akio Hoshi, Yukihiro Sato, Toyomasa Koda, Isao Yoshida, Kouzou Sakamoto
  • Patent number: 4814288
    Abstract: A method of fabricating semiconductor devices which include vertical elements and control elements. A well is formed by etching in a semiconductor substrate of a first conductivity type, and a first epitaxial layer having a second conductivity type opposite to the first conductivity type is epitaxially grown, followed by etching and/or grinding and/or polishing to fill said well. Further, a second epitaxial layer of the first conductivity type is epitaxially grown on the substrate and on the first epitaxial layer, and an impurity-doped layer of the second conductivity type for isolation is formed in the second epitaxial layer to penetrate therethrough. A first element is formed in the second epitaxial layer in a portion that corresponds to the well, and a second element having a vertical structure and having a current capability higher than that of the first element is formed except a portion of the second epitaxial layer that corresponds to the well.
    Type: Grant
    Filed: July 10, 1987
    Date of Patent: March 21, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Kimura, Takeaki Okabe, Isao Yoshida, Kouzou Sakamoto, Kazuo Hoya, Kouichiro Satonaka, Toyomasa Koda, Shigeo Ohtaka
  • Patent number: 4443812
    Abstract: A high-breakdown-voltage semiconductor device wherein a resistor body made of a P-type impurity region is disposed in a surface region of an N-type semiconductor body so as to form a resistor element, a P-type low doped region is disposed around the resistor body, and a plate layer which extends from a high potential electrode of the resistor body covers a main part of the P-type low doped region.
    Type: Grant
    Filed: February 4, 1981
    Date of Patent: April 17, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Ichiro Imaizumi, Masatoshi Kimura, Shikayuki Ochi, Masayoshi Yoshimura, Takashi Yamaguchi, Toyomasa Koda
  • Patent number: 4423433
    Abstract: A high-breakdown-voltage resistance element comprises a semiconductor body, an impurity layer disposed in a surface region of the semiconductor body to provide a resistor body, a first electrode connected to one end of the resistor body through a contact hole in a first insulating film formed on the surface of the semiconductor body, and a second electrode connected to the other end of the resistor body through another contact hole in the insulating film. A second insulating film is formed on the first and second electrodes, and a third electrode is connected to the first electrode through a contact hole in the second insulating film, so that the entire surface of the resistor body and adjacent areas are covered with the first, second and third electrodes.
    Type: Grant
    Filed: June 3, 1980
    Date of Patent: December 27, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Ichiro Imaizumi, Shikayuki Ochi, Masatoshi Kimura, Masayoshi Yoshimura, Takashi Yamaguchi, Toyomasa Koda