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:
Jun. 10, 2014
Filed:
Oct. 12, 2010
Andreas Fuchs, Meerbusch, DE;
Maurits Van Der Schaar, Eindhoven, NL;
Scott Anderson Middlebrooks, Duizel, NL;
Panagiotis Pieter Bintevinos, Best, NL;
Andreas Fuchs, Meerbusch, DE;
Maurits Van Der Schaar, Eindhoven, NL;
Scott Anderson Middlebrooks, Duizel, NL;
Panagiotis Pieter Bintevinos, Best, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
A method and associated apparatus determine an overlay error on a substrate. A beam is projected onto three or more targets. Each target includes first and second overlapping patterns with predetermined overlay offsets on the substrate. The asymmetry of the radiation reflected from each target on the substrate is measured. The overlay error not resultant from the predetermined overlay offsets is determined. The function that enables calculation of overlay from asymmetry for other points on the wafer is determined by limiting the effect of linearity error when determining the overlay error from the function.