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. 11, 2022
Filed:
Jul. 13, 2017
Asml Netherlands B.v, Veldhoven, NL;
Maurits Van Der Schaar, Eindhoven, NL;
Kaustuve Bhattacharyya, Veldhoven, NL;
Hendrik-Jan Hidde Smilde, Veldhoven, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
A lithographic process is used to form a plurality of target structures distributed at a plurality of locations across a substrate and having overlaid periodic structures with a number of different overlay bias values distributed across the target structures. At least some of the target structures comprising a number of overlaid periodic structures (e.g., gratings) that is fewer than said number of different overlay bias values. Asymmetry measurements are obtained for the target structures. The detected asymmetries are used to determine parameters of a lithographic process. Overlay model parameters including translation, magnification and rotation, can be calculated while correcting the effect of bottom grating asymmetry, and using a multi-parameter model of overlay error across the substrate.