Patents by Inventor Fusao Tabata

Fusao Tabata 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).

  • Method for manufacturing silicon single crystal
    Patent number: 6340390
    Abstract: A method for manufacturing a silicon single crystal. In this method, silicon material melting is performed in a furnace having an internal pressure between 60 and 400 mbar. The subsequent single crystal pulling is performed in a furnace having an internal pressure which is lower than the pressure when the silicon material is molten, but not exceeding 95 mbar. This method prevents production of a defective single crystal which results from the formation of pinholes, prevents dislocation of the single crystal which results from bubbles and impurities present in silicon melting solution, and prevents dislocation of the single crystal which results from evaporation of the SiO.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: January 22, 2002
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Hiroshi Asano, Yukio Sugimoto, Fusao Tabata