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. 26, 2019
Filed:
Nov. 02, 2017
Carl Zeiss Smt Gmbh, Oberkochen, DE;
Thomas Fischer, Aalen, DE;
Sarina Wunderlich, Oberkochen, DE;
Carl Zeiss SMT GmbH, Oberkochen, DE;
Abstract
A facet mirror for EUV projection lithography has a plurality of facets for reflecting EUV illumination light. At least some of the facets are in the form of alignment facets and have a reflection surface, the edge contour of which is aligned along two alignment coordinates of an overall facet arrangement. The reflection surface of at least one of the alignment facets has a surface shape that exhibits different curvatures along two axes of curvature. The axes of curvature are tilted about a finite axis tilt angle relative to the alignment coordinates of the overall facet arrangement. The result is a facet mirror with increased EUV throughput, particularly for prolonged operation of a projection exposure apparatus that is equipped therewith.