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:
Jun. 11, 2013
Filed:
Aug. 20, 2009
Applicants:
Shigeru Umeno, Tokyo, JP;
Manabu Nishimoto, Tokyo, JP;
Masataka Hourai, Tokyo, JP;
Inventors:
Assignee:
Sumco Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C30B 15/00 (2006.01); C30B 21/06 (2006.01);
U.S. Cl.
CPC ...
Abstract
A silicon wafer is produced through the steps of forming a silicon ingot by a CZ method with an interstitial oxygen concentration of not more than 7.0×10atoms/cmand with a diameter of a COP occurring region not more than a diameter of a crystal, slicing a wafer from the silicon ingot after doping the silicon ingot with phosphorus, forming a polysilicon layer or a strained layer on one main surface of the wafer, and mirror polishing the other main surface of the wafer.