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:
Aug. 16, 2022
Filed:
Apr. 05, 2018
Asml Netherlands B.v., Veldhoven, NL;
Wim Tjibbo Tel, Helmond, NL;
Bart Laenens, San Jose, CA (US);
ASML Netherlands B.V., Veldhoven, NL;
Abstract
Methods and apparatus for determining a focus of a projection system are disclosed. In one arrangement, a method includes obtaining first data derived from a first measurement of one or more selected properties of a target pattern formed on a substrate by exposing the substrate using the projection system. The first measurement is performed before the substrate is etched based on the target pattern. The method further includes obtaining second data derived from a second measurement of the one or more selected properties of the target pattern. The second measurement is performed after the substrate is etched based on the target pattern. The method further includes determining the focus of the projection system using the first data and the second data.