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. 25, 2021
Filed:
Aug. 26, 2019
Kla Corporation, Milpitas, CA (US);
Andrew Zeng, Fremont, CA (US);
Helen Heng Liu, Fremont, CA (US);
KLA Corporation, Milpitas, CA (US);
Abstract
An inspection system may include a controller coupled to a differential interference contrast imaging tool for generating images of a sample based on illumination with two sheared illumination beams. The controller may determine a first defect-induced phase shift based on a first set of images of a defect on the sample with a first selected illumination spectrum and two or more selected induced phase differences between the two sheared illumination beams, determine a second defect-induced phase shift based a second set of images of the defect with a second selected illumination spectrum and two or more selected induced phase differences between the two sheared illumination beams, and classify the defect as a metal or a non-metal based on a comparison of the first phase shift to the second phase shift.