Patents by Inventor Seizou Doi

Seizou Doi 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).

  • Impurity concentrator and analyzer
    Patent number: 5746829
    Abstract: The invention provides a method for concentrating impurity contained in a semiconductor crystal sample 11 by irradiating repeatedly a specified position of the semiconductor crystal sample 11 with a laser beam having a specified intensity by means of a laser oscillator 13. Then the invention provides a method for analyzing impurity contained in the impurity concentrated area of the semiconductor crystal sample 11 in high sensitivity by means of a specified physical analyzing means. According to demand, a method of the invention concentrates impurity by means of a laser beam after forming an insulating film such as an oxide film and the like transparent to the laser beam on the surface of the semiconductor crystal sample. At the same time, the invention provides a concentrator and an analyzer to be used for these concentrating method and analyzing method.
    Type: Grant
    Filed: September 10, 1996
    Date of Patent: May 5, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideki Matsunaga, Hiroshi Yamaguchi, Mitsuhiro Tomita, Seizou Doi, Masahiko Yoshiki, Shoji Kozuka, Masayuki Onuma