Patents by Inventor Tadashi Niwayama

Tadashi Niwayama 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: 5885365
    Abstract: A method for cleaning and drying crucibles for use in pulling single crystals by the Czochralski method after transportation of the crucibles, includes cleaning a crucible in a cleaning process; warming the crucible with pure water heated at a temperature of at least 50.degree. C.; and drying the warmed crucible under ambient conditions.
    Type: Grant
    Filed: March 12, 1997
    Date of Patent: March 23, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Shiniti Sugai, Kouzou Yokota, Tadashi Niwayama, Michiaki Oda, Shiniti Kon
  • Patent number: 5394829
    Abstract: A device for pulling a silicon single crystal is constructed so as to preclude deposition of a SiO-derived substance on graphite parts inside the device and prevent the graphite parts from deterioration, elongate the duration of continuous use of the device in a great measure, and simplify the disassembly and reassembly of the device.This device pulls a silicon single crystal in an atmosphere of inert gas by the Czochralski method, which device is chracterized by comprising a crucible 1 for accommodating a molten silicon mass 2, a heater 3 disposed round the periphery of the crucible 1, an outer member 14 forming a pulling chamber 6 for accomodating the crucible 1, an inert gas inlet part 15 disposed in the upper part of the pulling chamber 6, and an inert gas outlet part 16 separated from the inert gas inlet part 15 in the same upper part of the pulling chamber 6.
    Type: Grant
    Filed: March 23, 1993
    Date of Patent: March 7, 1995
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Toshiharu Uesugi, Koji Mizuishi, Atsushi Iwasaki, Tadashi Niwayama, Tetsuhiro Oda