Patents by Inventor Shin Ohwada

Shin Ohwada 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: 6435956
    Abstract: The present invention provides a substrate holding apparatus which can adjust a holding state of a substrate in accordance with a polishing state, and maintain uniformity of a polishing amount over an entire surface of the substrate, or control the polishing amount intentionally. The substrate holding apparatus comprises a holding plate having a holding surface for a substrate, a cover element for covering a backside surface of the holding plate to form a sealed back pressure space at the backside surface side, a plurality of through-holes distributed over the substantially entire holding surface for allowing the holding surface to communicate with the back pressure space, a division element removably provided for dividing the back pressure space between the holding plate and the cover element into a plurality of predetermined sealed divisional spaces in a plane, and a back pressure controller for individually controlling back pressures in the divisional spaces.
    Type: Grant
    Filed: October 2, 2000
    Date of Patent: August 20, 2002
    Assignee: Ebara Corporation
    Inventors: Shin Ohwada, Teruhiko Ichimura
  • Patent number: 6293858
    Abstract: A polishing apparatus for polishing a workpiece such as a semiconductor wafer to a flat mirror finish includes a turntable with a polishing cloth mounted on an upper surface thereof and a top ring for polishing a semiconductor wafer to a flat mirror finish by placing the semiconductor wafer between the turntable and the top ring and pressing the semiconductor wafer under a certain pressing force. A presser ring is vertically movably provided around the top ring. A pressing device presses the presser ring against the polishing cloth under a variable pressing force, and the presser ring is supported by the top ring through a bearing.
    Type: Grant
    Filed: December 6, 1999
    Date of Patent: September 25, 2001
    Assignee: Ebara Corporation
    Inventors: Norio Kimura, Toru Maruyama, Shunichiro Kojima, Seiji Katsuoka, Shin Ohwada