Patents by Inventor Makiko Wakatsuki

Makiko Wakatsuki 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).

  • Wafer processsing method for manufacturing wafers having contaminant-gettering damage on one surface
    Patent number: 5071776
    Abstract: First, silicon wafers are formed by cutting silicon monocrystalline ingot into slices. Then back side and main surfaces of the wafers are subjected to lapping and etching processes. Next, the wafers are submerged into substantially pure water and ultrasonic waves are applied to the wafer surface via the water to clean at least one of the surfaces of each of the wafers and form gettering damage on the wafer surface. After this, the main surfaces of the wafers which have been subjected to the cleaning and damage-forming process and on which semiconductor elements are to be formed are polished into mirror finish.
    Type: Grant
    Filed: November 25, 1988
    Date of Patent: December 10, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Matsushita, Moriya Miyashita, Makiko Wakatsuki, Norihiko Tsuchiya, Atsuko Kubota