Patents by Inventor Yuji Ontani

Yuji Ontani 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: 5439732
    Abstract: In a ceramic multi-layer wiring board, a surface conductor layer is made of a copper-based material and an inner conductor in the ceramic multilayer is a non-copper metal having a melting point higher than a temperature at which the ceramic multilayer is fired, typically Ag. Cu and Ag form eutectic crystals when firing the surface conductor layer of Cu. This can be prevented by connecting the surface conductor layer and the inner conductor with Ag-Pd or a metal which is different from the materials of the surface wiring layer and the inner conductor and which does not form eutectic crystals with the material of the surface wiring layer at the temperature at which the surface wiring layer is fired.
    Type: Grant
    Filed: January 21, 1994
    Date of Patent: August 8, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventors: Takashi Nagasaka, Yuji Ontani, Mitsuhiro Saitou