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:
Nov. 22, 2016
Filed:
Feb. 03, 2011
Toshiaki Ono, Tokyo, JP;
Jun Fujise, Tokyo, JP;
Toshiaki Ono, Tokyo, JP;
Jun Fujise, Tokyo, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
An object of the present invention is to provide an epitaxial wafer on which dislocation is preventable even when a LSA treatment is performed in device processes. An epitaxial wafer according to the present invention includes a waferwhose nitrogen concentration is 1×10atoms/cmor more or whose specific resistance is 20 mΩ·cm or less by boron doping, and an epitaxial layerprovided on the wafer. On the wafer, if a thermal treatment is performed at 750° C. for 4 hours and then at 1,000° C. for 4 hours, polyhedron oxygen precipitates grow predominantly over plate-like oxygen precipitates. Therefore, in the device processes, plate-like oxygen precipitates cannot be easily formed. As a result, even when the LSA treatment is performed after various thermal histories in the device processes, it is possible to prevent the dislocation, which is triggered by oxygen precipitates, from generating.