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:
Feb. 28, 2023
Filed:
Mar. 31, 2021
Kla Corporation, Milpitas, CA (US);
Amnon Manassen, Haifa, IL;
Andrew Hill, Portland, OR (US);
Yonatan Vaknin, Migdal Ha'emek, IL;
Yossi Simon, Qiryat Atta, IL;
Daria Negri, Haifa, IL;
Vladimir Levinski, Migdal Ha'emek, IL;
Yuri Paskover, Binyamina, IL;
Anna Golotsvan, Qiryat Tivon, IL;
Nachshon Rothman, DN Oshrat, IL;
Nireekshan K. Reddy, Tel Aviv, IL;
Nir BenDavid, Migdal Ha'emek, IL;
Avi Abramov, Haifa, IL;
Dror Yaacov, Migdal Ha'emek, IL;
Yoram Uziel, Migdal Ha'emek, IL;
Nadav Gutman, Zichron Ya'aqov, IL;
KLA Corporation, Milpitas, CA (US);
Abstract
A method for metrology includes directing at least one illumination beam to illuminate a semiconductor wafer on which at least first and second patterned layers have been deposited in succession, including a first target feature in the first patterned layer and a second target feature in the second patterned layer, overlaid on the first target feature. A sequence of images of the first and second target features is captured while varying one or more imaging parameters over the sequence. The images in the sequence are processed in order to identify respective centers of symmetry of the first and second target features in the images and measure variations in the centers of symmetry as a function of the varying image parameters. The measured variations are applied in measuring an overlay error between the first and second patterned layers.