US 11,733,614 B2
Method of metrology and associated apparatuses
Thomas Jarik Huisman, Eindhoven (NL); Ruben Cornelis Maas, Utrecht (NL); and Hermanus Adrianus Dillen, Maarheeze (NL)
Assigned to ASML Netherlands B.V., Veldhoven (NL)
Filed by ASML Netherlands B.V., Veldhoven (NL)
Filed on Sep. 6, 2021, as Appl. No. 17/467,441.
Application 17/467,441 is a continuation of application No. 16/362,025, filed on Mar. 22, 2019, granted, now 11,112,703.
Claims priority of application No. 18163680 (EP), filed on Mar. 23, 2018.
Prior Publication US 2022/0107571 A1, Apr. 7, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G06T 7/12 (2017.01); G03F 7/00 (2006.01); G01B 9/04 (2006.01); G03F 1/84 (2012.01); G03F 1/86 (2012.01)
CPC G03F 7/70625 (2013.01) [G01B 9/04 (2013.01); G03F 1/84 (2013.01); G03F 1/86 (2013.01); G06T 7/12 (2017.01); G06T 2207/10061 (2013.01); G06T 2207/20168 (2013.01); G06T 2207/30148 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A non-transitory computer readable medium storing a set of instructions that are executable by one or more processors of an apparatus to cause the apparatus to perform a method for determining an edge position relating to an edge of a feature, the method comprising:
determining a reference signal from an inspection image by applying a 1-dimensional low-pass filter to the inspection image; and
determining the edge position based on a matched edge-contour and a threshold characteristic of the inspection image, the matched edge-contour comprising a matched estimate of the edge position based on the reference signal.