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, 2017
Filed:
Oct. 27, 2015
Kla-tencor Corporation, Milpitas, CA (US);
Stilian Ivanov Pandev, Santa Clara, CA (US);
Siddharth Srivastava, Hayward, CA (US);
KLA-Tencor Corporation, Milpitas, CA (US);
Abstract
Methods and systems for measuring overlay error between structures formed on a substrate by successive lithographic processes are presented herein. Two overlay targets, each having programmed offsets in opposite directions are employed to perform an overlay measurement. Overlay error is measured based on zero order scatterometry signals and scatterometry data is collected from each target at two different azimuth angles. In addition, methods and systems for creating an image-based measurement model based on measured, image-based training data are presented. The trained, image-based measurement model is then used to calculate values of one or more parameters of interest directly from measured image data collected from other wafers. The methods and systems for image based measurement described herein are applicable to both metrology and inspection applications.