Patents by Inventor Ryousei Kawa-ai

Ryousei Kawa-ai 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).

  • Polishing method and apparatus
    Patent number: 6478977
    Abstract: The present invention relates to a polishing method using a grindstone comprising abrasive grains and a bonding resin for bonding the abrasive grains, as well as to a polishing apparatus to be used for the polishing method. By using a resin for bonding abrasive grains, it is possible to obtain a grindstone having a desired modulus of elasticity. With such a grindstone, the surface of a substrate having concave and convex portions can be rendered uniformly flat, irrespective of the size of the concave and convex portions. Further, by first polishing the substrate surface with a polishing tool of a small elastic modulus and thereafter polishing it with a polishing tool of a large elastic modulus, it is possible to obtain a polished surface of reduced damage. The method of the invention is effective in planarizing various substrate surfaces having concave and convex portions.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: November 12, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Moriyama, Katsuhiko Yamaguchi, Yoshio Homma, Sunao Matsubara, Yoshihiro Ishida, Ryousei Kawa-ai
  • Polishing method and apparatus
    Patent number: 6180020
    Abstract: The present invention relates to a polishing method using a grindstone comprising abrasive grains and a bonding resin for bonding the abrasive grains, as well as to a polishing apparatus to be used for the polishing method. By using a resin for bonding abrasive grains, it is possible to obtain a grindstone having a desired modulus of elasticity. With such a grindstone, the surface of a substrate having concave and convex portions can be rendered uniformly flat, irrespective of the size of the concave and convex portions. Further, by first polishing the substrate surface with a polishing tool of a small elastic modulus and thereafter polishing it with a polishing tool of a large elastic modulus, it is possible to obtain a polished surface of reduced damage. The method of the invention is effective in planarizing various substrate surfaces having concave and convex portions.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: January 30, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Moriyama, Katsuhiko Yamaguchi, Yoshio Homma, Sunao Matsubara, Yoshihiro Ishida, Ryousei Kawa-ai