Patents by Inventor Kouzou Yokota

Kouzou Yokota 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: 8821636
    Abstract: The present invention is a single-crystal manufacturing apparatus based on the Czochralski method having a main chamber configured to accommodate hot zone components including a crucible, and a pull chamber configured to accommodate and take out a single crystal pulled from a raw material melt, the apparatus further comprising a multipurpose chamber interchangeable with the pull chamber, wherein a heating means for heating a raw material charged into the crucible and a cooling means for cooling the hot zone components after pulling the single crystal are placeable in the multipurpose chamber respectively. As a result, there is provided a single-crystal manufacturing apparatus that enables, in manufacture of a single crystal of a large diameter, e.g., approximately 200 mm or more, an operating rate of the single-crystal manufacturing apparatus and productivity of the single crystal to be improved.
    Type: Grant
    Filed: April 24, 2009
    Date of Patent: September 2, 2014
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Takao Abe, Kouzou Yokota, Kouji Mizuishi
  • Publication number: 20110030612
    Abstract: The present invention is a single-crystal manufacturing apparatus based on the Czochralski method having a main chamber configured to accommodate hot zone components including a crucible, and a pull chamber configured to accommodate and take out a single crystal pulled from a raw material melt, the apparatus further comprising a multipurpose chamber interchangeable with the pull chamber, wherein a heating means for heating a raw material charged into the crucible and a cooling means for cooling the hot zone components after pulling the single crystal are placeable in the multipurpose chamber respectively. As a result, there is provided a single-crystal manufacturing apparatus that enables, in manufacture of a single crystal of a large diameter, e.g., approximately 200 mm or more, an operating rate of the single-crystal manufacturing apparatus and productivity of the single crystal to be improved.
    Type: Application
    Filed: April 24, 2009
    Publication date: February 10, 2011
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Takao Abe, Kouzou Yokota, Kouji Mizuishi
  • 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: 5356113
    Abstract: An isolation valve for a single crystal pulling apparatus providing a good sealing performance is disclosed. The apparatus comprises a casing having two opposite valve seats, a first valve seat having a first opening communicable with the main chamber of the apparatus, a second valve seat having a second opening communicable with the pull chamber of the apparatus. The body of the isolation valve includes a first plate movable in and out of contact with the first valve seat to open and shut the first opening, a second plate movable in and out of contact with the second valve seat to open and shut the second opening, and a bellows connecting the first and second plates.
    Type: Grant
    Filed: September 23, 1993
    Date of Patent: October 18, 1994
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Koji Mizuishi, Kouzou Yokota, Katsuhiko Ogino