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. 01, 2024
Filed:
Feb. 18, 2022
Kla Corporation, Milpitas, CA (US);
Yoel Feler, Haifa, IL;
Mark Ghinovker, Yoqneam Ilit, IL;
Diana Shaphirov, Yoqneam Illit, IL;
Evgeni Gurevich, Yokneam Illit, IL;
Vladimir Levinski, Nazareth Ilit, IL;
KLA Corporation, Milpitas, CA (US);
Abstract
A metrology target may include a first rotationally symmetric working zone with one or more instances of a first pattern and a second rotationally-symmetric working zone with one or more instances of a second pattern, where at least one of the first pattern or the second pattern is a Moiré pattern formed from a first grating structure with a first pitch along a measurement direction on a first sample layer and a second grating structure with a second pitch different than the first pitch along the measurement direction on a second sample layer. Centers of rotational symmetry of the first and second working zones may overlap by design when an overlay error between the first sample layer and the second layer is zero. A difference between the centers of rotational symmetry of the first and second working zones may indicate an overlay error between the first and second sample layers.