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:
May. 26, 2009
Filed:
Aug. 10, 2005
Yonghang Fu, Plano, TX (US);
Yongqiang Liu, Plano, TX (US);
Michael J. Darwin, Beaverton, OR (US);
Rudolph Technologies, Inc., Flanders, NJ (US);
Abstract
A method for inspecting objects such as semiconductor wafers. A staging platform and an optical platform are arranged so that the object may be staged and its surface scanned by optical equipment situated on the optical platform. During the scanning process, the surface is illuminated with light of a plurality of wavelengths, each strobed at a predetermined rate so that multiple images may be collected using time and frequency multiplexing. The multiple images are stored in a database for analysis, which includes processing selected ones of the multiple images according to one or more algorithms. The defect-detection algorithms used for each object are determined by referenced to a predetermined or calculated defect detection protocol, then a defect mask is created for each pixel in the images that is suspected to be defective. The defect mask is then compared to threshold parameters to determine which if any of the suspected defects should be reported.