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:
May. 31, 2011
Filed:
Mar. 06, 2009
Johann Trenkler, Schwäbisch Gmünd, DE;
Hans-jürgen Mann, Oberkochen, DE;
Udo Nothelfer, Radebeul, DE;
Johann Trenkler, Schwäbisch Gmünd, DE;
Hans-Jürgen Mann, Oberkochen, DE;
Udo Nothelfer, Radebeul, DE;
CARL ZEISS SMT GmbH, Oberkochen, DE;
Abstract
A reflective optical element and an EUV lithography appliance containing one such element are provided, the appliance displaying a low propensity to contamination. The reflective optical element has a protective layer system consisting of at least one layer. The optical characteristics of the protective layer system are between those of a spacer and an absorber, or correspond to those of a spacer. The selection of a material with the smallest possible imaginary part and a real part which is as close to 1 as possible in terms of the refractive index leads to a plateau-type reflectivity course according to the thickness of the protective layer system between two thicknesses dand d. The thickness of the protective layer system is selected in such a way that it is less than d.