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:
Jul. 28, 2009
Filed:
Jul. 07, 2005
Sven Hansen, Kiefersfelden, DE;
Sven Hansen, Kiefersfelden, DE;
Sus MicroTec Lithography GmbH, Garching, DE;
Abstract
The invention provides a method for determining the center of a rotationally symmetrical alignment mark thereby using an image recognition software. The alignment mark is recognized by the image recognition software in different orientations by rotating the alignment mark around a symmetry angle with respect to which the alignment mark is rotationally symmetrical, and respective reference points are determined. The center of rotation of the determined reference points corresponds to the center of the alignment mark. Moreover, the invention provides a method for aligning two flat substrates each having a rotationally symmetrical alignment mark and being arranged substantially parallel with respect to each other. To this end, the centers of the alignment marks of the two substrates are determined by means of the method for determining the centers according to the present invention, and the two substrates are aligned by moving at least one of the two substrates in parallel so that the positions of the centers of the alignment marks coincide.