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:
Jun. 06, 1995
Filed:
Aug. 31, 1993
Patrick D Kinney, Coon Rapids, MN (US);
Yuri S Uritsky, Foster City, CA (US);
Harry Q Lee, Mountain View, CA (US);
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
A method for reducing targeting errors encountered when trying to locate contaminant particles in a high-magnification imaging device, based on estimates of the particle positions obtained from a scanning device. The method of the invention includes scanning a semiconductor wafer in a scanning device, then preferably moving the wafer to a different orientation, and scanning the wafer again, to obtain at least two sets of particle coordinates that may differ slightly because of uncertainties in the scanning process. The multiple sets of coordinates are averaged to reduce the targeting errors, but only after transforming the coordinates to a common coordinate system. The transformation step includes computing transformation parameters for each possible pair of particles detected in at least two scans, averaging the results, and then transforming all of the particle coordinates to the common coordinate system. Optionally, the method may include discarding any transformation parameters that deviate too far from the average, and then computing the average transformation parameters again.