Patents by Inventor Toshio Chuma

Toshio Chuma 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 and production process thereof, as well as wire bonding device used therefor
    Patent number: 4976393
    Abstract: The present invention concerns a semiconductor device and a process for producing semiconductor device, as well as a wire bonding device used therefor.In accordance with the present invention, a ball formed at the top end of a bonding wire is sphericalized by electric discharge within a reducing gas atmosphere at a high temperature from 100.degree. C. to 200.degree. C. By using the ball of the bonding wire formed under such a condition to the bonding of the bonding pad of a semiconductor pellet, it is possible to conduct highly reliable ball bonding with excellent bondability and with no development of cracks or the like in the semiconductor pellet, as well as to obtain a highly reliable semiconductor device, that is, LSI or IC.
    Type: Grant
    Filed: December 17, 1987
    Date of Patent: December 11, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Nakajima, Yoshio Ohashi, Toshio Chuma, Kazuo Hatori, Isao Araki, Masahiro Koizumi, Jin Onuki, Hitoshi Suzuki, Susumu Okikawa