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:
Nov. 26, 2002
Filed:
Jun. 15, 2000
Applicant:
Inventors:
John C. Stover, Charlotte, NC (US);
Yuri A. Eremin, Moscow, RU;
Assignee:
ADE Corporation, Westwood, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N 2/100 ; G01N 2/183 ;
U.S. Cl.
CPC ...
G01N 2/100 ; G01N 2/183 ;
Abstract
P-polarized light or having a strong P-polarized component is directed onto a filmed substrate at two (or more) different incidence angles, one angle being relatively large and the other angle being relatively small as measured from a surface normal. Light that is scattered into a back region of the hemispherical space above the substrate surface is collected and the intensity of the collected light is measured for each of the two incident angles. A defect can be classified as either a hole in the film or a particle on the film based on the relative intensities of the collected light.