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:
Jan. 12, 1999
Filed:
May. 07, 1997
Applicant:
Inventors:
Henry K Chau, San Francisco, CA (US);
Arun A Aiyer, Fremont, CA (US);
Assignee:
Nikon Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G01N / ; C06K / ;
U.S. Cl.
CPC ...
356237 ; 382149 ; 382218 ;
Abstract
Macro defects in a processed or partly processed semiconductor wafer, liquid crystal display element, disk drive element or the like, are detected using scattered light. By use of automated image processing techniques, a reference image and a sample image are formed from the scattered light and edge enhanced. A difference image is formed by comparing the edge enhanced reference and sample images. The difference image is evaluated using one or more automated image processing techniques such as thresholding, morphological transformations and blob analysis to identify macro defects.