	US 12,189,305 B2
	Metrology method and apparatus and computer program
Simon Gijsbert Josephus Mathijssen, Rosmalen (NL); Patricius Aloysius Jacobus Tinnemans, Hapert (NL); Arie Jeffrey Den Boef, Waalre (NL); Kaustuve Bhattacharyya, Veldhoven (NL); and Samee Ur Rehman, Milpitas, CA (US)
Assigned to ASML Netherlands B.V., Veldhoven (NL)
Appl. No. 18/004,555
Filed by ASML Netherlands B.V., Veldhoven (NL)
PCT Filed May 27, 2021, PCT No. PCT/EP2021/064156 § 371(c)(1), (2) Date Jan. 6, 2023, PCT Pub. No. WO2022/008135, PCT Pub. Date Jan. 13, 2022.
Claims priority of provisional application 63/049,897, filed on Jul. 9, 2020.
Prior Publication US 2024/0027918 A1, Jan. 25, 2024
Int. Cl. G03F 7/00 (2006.01); G03F 9/00 (2006.01)

CPC G03F 7/70633 (2013.01) [G03F 9/7042 (2013.01); G03F 9/7046 (2013.01)]

14 Claims

1. A method of improving a measurement of a parameter of interest comprising:

obtaining metrology data comprising a plurality of measured values of the parameter of interest, relating to one or more targets on a substrate, each measured value relating to a different measurement combination of a target of the one or more targets and a measurement condition used to measure that target;

obtaining asymmetry metric data relating to asymmetry for the one or more targets;

determining a respective relationship for each of the measurement combinations relating a true value for the parameter of interest to the asymmetry metric data, based on an assumption that there is a common true value for the parameter of interest over the measurement combinations; and

using one or more of the respective relationships to improve a measurement of the parameter of interest.