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:
Sep. 17, 2013
Filed:
Jul. 14, 2010
Applicant:
Shouhong Tang, Santa Clara, CA (US);
Inventor:
Shouhong Tang, Santa Clara, CA (US);
Assignee:
KLA Tencor, Milpitas, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B 11/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method and system is disclosed for utilizing two single-shot phase shift interferometers to simultaneously measure wafer shape and thickness variation of two sides of a wafer. This system is able to extract the front height, the back height, and the thickness variation of a wafer in a single data acquisition. This system, when utilized with a fast shutter speed, decreases the insensitivity to vibration. Algorithms are introduced that extract the true thickness variation of a wafer even when the wafer is vibrating. The effects of air turbulence can be reduced by a phase averaging technique.