The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 2009
Filed:
Sep. 01, 2004
Applicants:
Akihiko Endo, Tokyo, JP;
Hideki Nishihata, Tokyo, JP;
Inventors:
Akihiko Endo, Tokyo, JP;
Hideki Nishihata, Tokyo, JP;
Assignee:
Sumco Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 21/30 (2006.01); H01L 21/44 (2006.01);
U.S. Cl.
CPC ...
Abstract
A thickness of silicon oxide film of a wafer for active layer is controlled to be thinner than that of buried silicon oxide film. Consequently, uniformity in film thickness of the active layer of a bonded wafer is improved even if a variation in the in-plane thickness of the silicon oxide film is large at a time of ion implantation. Furthermore, since the silicon oxide film is rather thinner and thereby the ion implantation depth is relatively deeper, damages to the active layer and the buried silicon oxide film caused by the ion implantation can be reduced.