Patents by Inventor Shu Sugisawa

Shu Sugisawa 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: 8916953
    Abstract: The present invention provides a method for manufacturing a silicon single crystal wafer, in which a heat treatment is performed with respect to a silicon single crystal wafer having oxygen concentration of less than 7 ppma and nitrogen concentration of 1×1013 to 1×1014 atoms/cm3, which is obtained from a V-region silicon single crystal ingot grown by the Czochralski method, in a non-nitriding atmosphere at 1150 to 1300° C. for 1 to 120 minutes. As a result, a method for manufacturing a low-cost silicon single crystal wafer which is applicable to an IGBT by using a V-region wafer that is manufactured by the CZ method which can cope with an increase in diameter, by making a bulk have no defects and by providing a radial resistivity distribution, which is substantially equal to that when the neutron irradiation is effected, without performing the neutron irradiation is provided.
    Type: Grant
    Filed: January 6, 2012
    Date of Patent: December 23, 2014
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Wei Feng Qu, Fumio Tahara, Yuuki Ooi, Shu Sugisawa
  • Publication number: 20130264685
    Abstract: The present invention provides a method for manufacturing a silicon single crystal wafer, in which a heat treatment is performed with respect to a silicon single crystal wafer having oxygen concentration of less than 7 ppma and nitrogen concentration of 1×1013 to 1×1014 atoms/cm3, which is obtained from a V-region silicon single crystal ingot grown by the Czochralski method, in a non-nitriding atmosphere at 1150 to 1300° C. for 1 to 120 minutes. As a result, a method for manufacturing a low-cost silicon single crystal wafer which is applicable to an IGBT by using a V-region wafer that is manufactured by the CZ method which can cope with an increase in diameter, by making a bulk have no defects and by providing a radial resistivity distribution, which is substantially equal to that when the neutron irradiation is effected, without performing the neutron irradiation is provided.
    Type: Application
    Filed: January 6, 2012
    Publication date: October 10, 2013
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Wei Feng Qu, Fumio Tahara, Yuuki Ooi, Shu Sugisawa