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. 10, 2015
Filed:
Jan. 21, 2014
Kla-tencor Corporation, Milpitas, CA (US);
KLA-Tencor Corporation, Milpitas, CA (US);
Abstract
A method and system for overly measurement is disclosed. The overlay measurement is performed based on moiré effect observed between structured illumination grids and overlay targets. A structured illumination is used to illuminate a first overlay target and a second overlay target. Upon obtaining an image of the first overlay target illuminated by the structured illumination and an image of the second overlay target illuminated by the structured illumination, relative displacement between the first overlay target and the structured illumination and relative displacement between the second overlay target and the structured illumination are measured. The overlay between the first overlay target and the second overlay target is then measured based on their relative displacements with respect to the structured illumination.