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:
Jul. 18, 2000
Filed:
Mar. 22, 1999
Applicant:
Inventor:
Robert Bishop, Newton, MA (US);
Assignee:
Beltronics, Inc., , US;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
3562375 ;
Abstract
Semiconductor wafers, circuit boards and similar multi-layer structures are optically inspected at high speeds with the aid of preferably a pair of oppositely and inclinedly directed laser beams at inclined angles to the vertical and the wafer surface to cause fluorescence by a photoresist layer carrying conductor patterns, defects in which are to be inspected, and using preferably a time-delay-integration CCD imaging camera for recording a fluorescent resist surface image accentuating the non-fluorescing conductor pattern thereupon, while masking all light from layers therebelow.