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. 04, 2012
Filed:
Nov. 06, 2008
Applicants:
Takashi Fujikawa, Tokyo, JP;
Seiji Sugimoto, Tokyo, JP;
Inventors:
Takashi Fujikawa, Tokyo, JP;
Seiji Sugimoto, Tokyo, JP;
Assignee:
Sumco Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 21/331 (2006.01);
U.S. Cl.
CPC ...
Abstract
An annular step portion provided to a periphery of a wafer housing portion is provided to an area with which an area of 1 to 6 mm from a boundary line with a chamfered surface of a wafer rear surface toward a wafer center comes in contact. As a result, it is possible to produce an epitaxial wafer having no scratch in a boundary area between the rear surface and the chamfered surface, and to eliminate particles generated due to a scratch in a device process.