Patents by Inventor Shigenao Ito

Shigenao Ito 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 and pad for polishing wafer
    Patent number: 7695347
    Abstract: A method for polishing a wafer effectively preventing a sag in an outer peripheral portion of a wafer and a polishing pad for polishing a wafer preferably used in the method for polishing a wafer are provided. The method for polishing a wafer comprises the step of: mirror-polishing a wafer with a main surface of the wafer being in contact with a polishing pad of non-woven fabric impregnated with resin, wherein a ratio of surface roughness of the polishing pad to compressibility thereof {surface roughness Ra (?m)/compressibility (%)} is 3.8 or more.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: April 13, 2010
    Assignees: Shin-Etsu Handotai Co., Ltd., Rodel Nitta Company
    Inventors: Hisashi Masumura, Kazuya Tomii, Shigenao Ito, Kenichi Anzai, Kenichi Inoue
  • Method and pad for polishing wafer
    Publication number: 20050014455
    Abstract: A method for polishing a wafer effectively preventing a sag in an outer peripheral portion of a wafer and a polishing pad for polishing a wafer preferably used in the method for polishing a wafer are provided. The method for polishing a wafer comprises the step of: mirror-polishing a wafer with a main surface of the wafer being in contact with a polishing pad of non-woven fabric impregnated with resin, wherein a ratio of surface roughness of the polishing pad to compressibility thereof {surface roughness Ra (?m)/compressibility (%)} is 3.8 or more.
    Type: Application
    Filed: October 25, 2002
    Publication date: January 20, 2005
    Inventors: Hisashi Masumura, Kazuya Tomii, Shigenao Ito, Kenichi Anzai, Kenichi Inoue