Patents Assigned to Tsiyo Sanso Co., Ltd.
  • Patent number: 4932168
    Abstract: A cleaning method and a gettering method for semiconductor wafers comprises blasting frozen particles at the surface of a semiconductor wafer. A processing apparatus for a semiconductor wafer comprises means for forming ultrafine frozen particles and means for blasting the frozen particles at the surface of a semiconductor wafer to perform either the gettering or the cleaning of the semiconductor wafer. In one form of the invention, the frozen particles are formed by spraying a mist of water into a chamber partially filled with liquid nitrogen, which freezes the mist to form ice particles. In another form of the invention, the frozen particles are formed by spraying a mist of water into a chamber containing cold nitrogen gas, which freezes the mist to form ice particles.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: June 12, 1990
    Assignees: Tsiyo Sanso Co., Ltd., Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masuo Tada, Takeki Hata, Takaaki Fukumoto, Toshiaki Ohmori