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:
Sep. 04, 2012
Filed:
Mar. 07, 2008
Michael Arnz, Oberkochen, DE;
Gerd Klose, Oberkochen, DE;
Michael Arnz, Oberkochen, DE;
Gerd Klose, Oberkochen, DE;
Carl Zeiss SMS GmbH, Jena, DE;
Abstract
A method is provided for determining the relative overlay shift of stacked layers, said method comprising the steps of: a) providing a reference image including a reference pattern that comprises first and second pattern elements; b) providing a measurement image of a measurement pattern, which comprises a first pattern element formed by a first one of the layers and a second pattern element formed by a second one of the layers; c) weighting the reference or measurement image such that a weighted first image is generated, in which the first pattern element is emphasized relative to the second pattern element; d) determining the relative shift of the first pattern element on the basis of the weighted first image and of the measurement or reference image not weighted in step c); e) weighting the reference or measurement image such that a weighted second image is generated, in which the second pattern element is emphasized relative to the first pattern element; f) determining the relative shift of the second pattern element on the basis of the weighted second image and of the measurement or reference image not weighted in step e); g) determining the relative overlay shift on the basis of the relative shifts determined in steps d) and f).