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:
Feb. 26, 2013
Filed:
Oct. 26, 2009
Applicants:
Katsuhiko Nakai, Yamaguchi, JP;
Masayuki Fukuda, Yamaguchi, JP;
Inventors:
Katsuhiko Nakai, Yamaguchi, JP;
Masayuki Fukuda, Yamaguchi, JP;
Assignee:
Siltronic AG, Munich, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C30B 15/14 (2006.01);
U.S. Cl.
CPC ...
Abstract
Silicon wafers wherein slip dislocations and warpages during device production are suppressed, contain BMDs with an octahedral shape, and of BMDs at a depth greater than 50 μm from the surface of the wafer, the density of BMDs with diagonal size of 10 nm to 50 nm is ≧1×10/cm, and the density of BSFs is ≦1×10/cm. The present silicon wafers preferably have an interstitial oxygen concentration of 4×10atoms/cmto 6×10atoms/cm, and a density of BMDs with diagonal size of ≧200 nm of not more than 1×10/cm.