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:
May. 12, 2020
Filed:
Feb. 24, 2017
Globalwafers Japan Co., Ltd., Niigata, JP;
Susumu Maeda, Niigata, JP;
Hironori Banba, Niigata, JP;
Haruo Sudo, Niigata, JP;
Hideyuki Okamura, Niigata, JP;
Koji Araki, Niigata, JP;
Koji Sueoka, Okayama, JP;
Kozo Nakamura, Okayama, JP;
GLOBALWAFERS JAPAN CO., LTD., Niigata, JP;
Abstract
A silicon wafer includes a denuded zone which is a surface layer and of which the density of vacancy-oxygen complexes which are complexes of vacancies and oxygen is less than 1.0×10/cm. An intermediate layer is disposed inwardly of the denuded zone so as to be adjacent to the denuded zone. The density of the vacancy-oxygen complexes in the intermediate layer increases gradually inwardly in the depth direction from the boundary with the denuded zone within a range of 1.0×10/cmor over and less than 5.0×10/cm. The intermediate layer has a depth determined corresponding to the depth of the denuded zone. A bulk layer is disposed inwardly of the intermediate layer so as to be adjacent to the intermediate layer. The density of the vacancy-oxygen complexes in the bulk layer is 5.0×10/cmor over.