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:
Aug. 22, 2023
Filed:
May. 06, 2021
Kla Corporation, Milpitas, CA (US);
Anatoly Romanovsky, Palo Alto, CA (US);
Jenn-Kuen Leong, San Jose, CA (US);
Daniel Kavaldjiev, San Jose, CA (US);
Chunhai Wang, Pleasanton, CA (US);
Bret Whiteside, Gilroy, CA (US);
Zhiwei Xu, Sunnyvale, CA (US);
KLA Corporation, Milpitas, CA (US);
Abstract
A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.