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:
Jun. 14, 2022
Filed:
May. 31, 2019
Carl Zeiss Smt Gmbh, Oberkochen, DE;
Carl Zeiss SMT GmbH, Oberkochen, DE;
Abstract
A catadioptric projection lens images a pattern of a mask in an effective object field of the projection lens into an effective image field of the projection lens with electromagnetic radiation with an operating wavelength λ<260 nm. The projection lens includes a multiplicity of lens elements and a multiplicity of mirrors including at least one concave mirror. The lens elements and mirrors define a projection beam path that extends from the object plane to the image plane and contains at least one pupil plane. The mirrors include a first mirror having a first mirror surface in the projection beam path between the object and pupil planes in the optical vicinity of a first field plane optically conjugate to the object plane. The mirrors also include a second mirror having a second mirror surface in the projection beam path between the pupil and image planes in the optical vicinity of a second field plane that is optically conjugate to the first field plane. The first mirror surface and/or the second mirror surface is a freeform surface.