Patents by Inventor Yasushi Yukimoto

Yasushi Yukimoto 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).

  • Publication number: 20120049330
    Abstract: A method of producing a silicon wafer comprises the steps of subjecting a silicon wafer, which has been sliced from a silicon single crystal ingot grown by the Czochralski method, to RTA treatment in a nitriding gas atmosphere; forming an oxide film on a surface of either side of the wafer; then forming a polysilicon layer thereon. The polysilicon layer on the front side of the wafer is removed and a wafer free of crystal defects in the surface part and with improved gettering performance is obtained. The polysilicon layer may be formed not on the surface of either side of the wafer but only on the back side thereof. It is desirable that a wafer composed of only a defect-free region is used as the source material since a defect-free layer can be stably secured in the wafer surface part.
    Type: Application
    Filed: April 9, 2010
    Publication date: March 1, 2012
    Applicant: SUMCO CORPORATION
    Inventor: Yasushi Yukimoto