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. 18, 2016
Filed:
Feb. 25, 2014
Asml Netherlands B.v., Veldhoven, 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 for determining overlay error includes measuring asymmetry of radiation reflected from each of a plurality of targets on a substrate. The plurality of targets include a predetermined overlay offset. The method also includes comparing the measured asymmetry of the radiation reflected from each of the plurality of targets to the corresponding predetermined overlay offset of the respective target. Additionally, the method includes determining the overlay error of a point on the substrate as a function of measured asymmetry reflected from the point. The function is determined by fitting a polynomial or a Fourier series to a comparison of the measured asymmetry of the radiation reflected from each of the plurality of targets to the corresponding predetermined overlay offset of the respective target. The function limits an effect of linearity error.