Patents by Inventor Takehiro Yuasa

Takehiro Yuasa 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).

  • Double-side polishing method
    Patent number: 9987721
    Abstract: A double-side polishing method of polishing both surfaces of a wafer by holding the wafer with a carrier including a holding hole configured to hold the wafer and a ring-shaped resin insert disposed along an internal circumference of the holding hole, the resin insert having an inner circumferential surface configured to contact a peripheral portion of the wafer, interposing the carrier between upper and lower turn tables to which polishing pads are attached, polishing both the surfaces of the wafer while maintaining planarity of the inner circumferential surface at or below 100 ?m and verticalness of the inner circumferential surface at or below 5°. The method can inhibit the degradation of the flatness of the polished wafer, such as particularly an outer circumferential sag, due to variation in shape of the inner circumferential surface of the resin insert of a carrier.
    Type: Grant
    Filed: August 8, 2013
    Date of Patent: June 5, 2018
    Inventors: Masanao Sasaki, Kazuaki Aoki, Taichi Yasuda, Taketoshi Sato, Takehiro Yuasa, Kazumasa Asai, Daisuke Furukawa
  • DOUBLE-SIDE POLISHING METHOD
    Publication number: 20150217425
    Abstract: A double-side polishing method of polishing both surfaces of a wafer by holding the wafer with a carrier including a holding hole configured to hold the wafer and a ring-shaped resin insert disposed along an internal circumference of the holding hole, the resin insert having an inner circumferential surface configured to contact a peripheral portion of the wafer, interposing the carrier between upper and lower turn tables to which polishing pads are attached, polishing both the surfaces of the wafer while maintaining planarity of the inner circumferential surface at or below 100 ?m and verticalness of the inner circumferential surface at or below 5°. The method can inhibit the degradation of the flatness of the polished wafer, such as particularly an outer circumferential sag, due to variation in shape of the inner circumferential surface of the resin insert of a carrier.
    Type: Application
    Filed: August 8, 2013
    Publication date: August 6, 2015
    Applicant: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masanao Sasaki, Kazuaki Aoki, Taichi Yasuda, Taketoshi Sato, Takehiro Yuasa, Kazumasa Asai, Daisuke Furukawa