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:
Oct. 20, 2009
Filed:
Apr. 23, 2008
Andreas Kirchner, Lorch, DE;
Bernhard Kneer, Altheim, DE;
Hans-jürgen Mann, Oberkochen, DE;
Carl Zeiss SMT AG, Oberkochen, DE;
Abstract
For the correction of anamorphism in the case of a projection lens of an EUV projection exposure apparatus for wafers it is proposed to tilt the reticle bearing the pattern to be projected and preferably also the wafer by a small angle about an axis that is perpendicular to the axis A of the lens and perpendicular to the scan direction and that in each instance passes through the middle of the light field generated on the reticle or on the wafer. For the correction of a substantially antisymmetric quadratic distortion the reticle and/or the substrate is instead rotated about an axis of rotation that is disposed at least approximately parallel to an optical axis of the projection lens.