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:
Oct. 12, 2017
Asml Netherlands B.v., Veldhoven, NL;
Hans Butler, Best, NL;
Johannes Petrus Martinus Bernardus Vermeulen, Leende, NL;
Marinus Petrus Reijnders, Eindhoven, NL;
ASML Netherlands B.V., Veldhoven, NL;
Abstract
A lithographic apparatus (LA) applies a pattern to a substrate (W). The lithographic apparatus includes a height sensor (LS), a substrate positioning subsystem, and a controller configured for causing the height sensor to measure the height (h) of the substrate surface at locations across the substrate. The measured heights are used to control the focusing of one or more patterns applied to the substrate. The height h is measured relative to a reference height (zref). The height sensor is operable to vary the reference height (zref), which allows a wider effective range of operation. Specifications for control of the substrate height during measurement can be relaxed. The reference height can be varied by moving one or more optical elements (and/or) within the height sensor, or moving the height sensor. An embodiment without moving parts includes a multi-element photodetector ().