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:
Jul. 22, 2003
Filed:
Dec. 29, 2000
Applicant:
Inventors:
Michael J. Ries, St. Charles, MO (US);
Charles Chiun-Chieh Yang, St. Peters, MO (US);
Robert W. Standley, Chesterfield, MO (US);
Assignee:
MEMC Electronic Materials, Inc., St. Peters, MO (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C30B 2/906 ;
U.S. Cl.
CPC ...
C30B 2/906 ;
Abstract
A single crystal silicon wafer with a back surface free of an oxide seal and substantially free of a chemical vapor deposition process induced halo and an epitaxial silicon layer on the front surface, the epitaxial layer is characterized by an axially symmetric region extending radially outwardly from the central axis of the wafer toward the circumferential edge of the wafer having a substantially uniform resistivity, the radius of the axially symmetric region being at least about 80% of the length of the radius of the wafer.