Patents by Inventor Masae Wada

Masae Wada 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 of recycling a delaminated wafer and a silicon wafer used for the recycling
    Publication number: 20010029072
    Abstract: There is disclosed a method of recycling a delaminated wafer produced as a by-product in producing an SOI wafer according to a hydrogen ion delaminating method by reprocessing it for reuse as a silicon wafer, wherein at least polishing of the delaminated wafer for removing of a step in the peripheral part of the delaminated wafer and heat treatment in a reducing atmosphere containing hydrogen are conducted as the reprocessing. There are provided a method of appropriately reprocessing a delaminated wafer produced as a by-product in a hydrogen ion delaminating method to reuse it as a silicon wafer actually, and particularly, a method of reprocessing an expensive wafer such as an epitaxial wafer many times for reuse, to improve productivity of SOI wafer having a high quality SOI layer, and to reduce producing cost.
    Type: Application
    Filed: June 5, 2001
    Publication date: October 11, 2001
    Applicant: Shin-Etsu Handotai Co., Ltd.
    Inventors: Susumu Kuwahara, Kiyoshi Mitani, Hiroji Aga, Masae Wada
  • Method of recycling a delaminated wafer and a silicon wafer used for the recycling
    Patent number: 6284628
    Abstract: There is disclosed a method of recycling a delaminated wafer produced as a by-product in producing an SOI wafer according to a hydrogen ion delaminating method by reprocessing it for reuse as a silicon wafer, wherein at least polishing of the delaminated wafer for removing of a step in the peripheral part of the delaminated wafer and heat treatment in a reducing atmosphere containing hydrogen are conducted as the reprocessing. There are provided a method of appropriately reprocessing a delaminated wafer produced as a by-product in a hydrogen ion delaminating method to reuse it as a silicon wafer actually, and particularly, a method of reprocessing an expensive wafer such as an epitaxial wafer many times for reuse, to improve productivity of SOI wafer having a high quality SOI layer, and to reduce producing cost.
    Type: Grant
    Filed: April 20, 1999
    Date of Patent: September 4, 2001
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Susumu Kuwahara, Kiyoshi Mitani, Hiroji Aga, Masae Wada