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:
Mar. 28, 2017
Filed:
Jun. 05, 2015
Carl Zeiss Smt Gmbh, Oberkochen, DE;
Norbert Wabra, Werneck, DE;
Boris Bittner, Roth, DE;
Martin Von Hodenberg, Oberkochen, DE;
Hartmut Enkisch, Aalen, DE;
Stephan Muellender, Aalen, DE;
Olaf Conradi, Westhausen, DE;
CARL ZEISS SMT GMBH, Oberkochen, DE;
Abstract
A reflective optical element of an optical system for EUV lithography and an associated manufacturing method. The reflective optical element () includes a multilayer system () for reflecting an incident electromagnetic wave having an operating wavelength in the EUV range, the reflected wave having a phase φ, and a capping layer () made from a capping layer material. The method includes determining a dependency according to which the phase of the reflected wave varies with the thickness d of the capping layer, determining a linearity-region in the dependency in which the phase of the reflected wave varies substantially linearly with the thickness of the capping layer, and creating a thickness profile in the capping layer such that both the maximum thickness and the minimum thickness in the thickness profile are in the linearity-region.