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. 29, 2000
Filed:
Feb. 26, 1998
Ankur H Desai, St. Peters, MO (US);
David L Vadnais, St. Charles, MO (US);
Robert W Standley, Chesterfield, MO (US);
MEMC Electronic Materials, Inc., St. Peters, MO (US);
Abstract
Process for the preparation of an epitaxial wafer having a total thickness variation and/or site total indicated reading of less than about 1.0 .mu.ms. The distance between the front and back surfaces of the epitaxial wafer at discrete positions on the front surface is measured to generate thickness profile data. Additional stock is removed from the front surface of the epitaxial wafer in a stock removal step to reduce the thickness of the epitaxial wafer to the target thickness, T.sub.t, with the amount of stock being removed at each of said discrete positions being determined after taking into account the thickness profile data and T.sub.t.