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. 28, 2008
Filed:
May. 13, 2005
Christoph Nölscher, Dresden, DE;
Joerg Tschischgale, Dresden, DE;
Christoph Nölscher, Dresden, DE;
Joerg Tschischgale, Dresden, DE;
Infineon Technologies AG, Munich, DE;
Abstract
A method of focus variation is described herein to achieve a one-step exposure of a wafer without the limitation of applying a complex y-tilt to a wafer stage. The position of the wafer surface to be exposed is periodically varied with respect to the focal plane, or vice versa. This relative movement between the focal plane, or best focus position along the optical axis and the wafer stage, or the wafer surface, is achieved by applying a movement to at least one of the reticle stage, one or more of the optical elements of the projection lens, and the wafer stage. The frequency of the movement is selected in dependence of the laser frequency (upper limit) or the scanning frequency (lower limit).
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile