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:
Oct. 27, 2020
Filed:
Jul. 12, 2018
Kla-tencor Corporation, Milpitas, CA (US);
David Gready, Tel Aviv, IL;
Nimrod Shuall, Beaverton, OR (US);
Claire Staniunas, Forest Grove, OR (US);
KLA Corporation, Milpitas, CA (US);
Abstract
A metrology system includes a controller coupled to a detector to image a sample based on the light captured by an objective lens, where an object plane of the detector with respect to the sample is adjustable. The controller may direct the detector to generate reference images of an overlay target on the sample at multiple object planes including at least a first reference image at a first sample layer and a second reference image at a second sample layer. The controller may further determine a reference overlay between the first layer and the second layer at the overlay target based on the first reference image and the second reference image. The controller may further select a measurement object plane for single-image overlay determination that corresponds to the reference overlay within a selected tolerance. The controller may further determine overlay for additional overlay targets at the measurement plane.