	US 12,259,659 B2
	Aligning a distorted image
Coen Adrianus Verschuren, Eindhoven (NL); Scott Anderson Middlebrooks, Duizel (NL); and Maxim Pisarenco, Son en Breugel (NL)
Assigned to ASML Netherlands B.V., Veldhoven (NL)
Filed by ASML Netherlands B.V., Veldhoven (NL)
Filed on Oct. 10, 2022, as Appl. No. 17/963,063.
Application 17/963,063 is a continuation of application No. PCT/EP2021/058546, filed on Mar. 31, 2021.
Claims priority of application No. 20169199 (EP), filed on Apr. 10, 2020.
Prior Publication US 2023/0036630 A1, Feb. 2, 2023
Int. Cl. G06T 7/00 (2017.01); G03F 7/00 (2006.01); G06V 10/75 (2022.01); G06V 10/764 (2022.01); G06V 10/82 (2022.01); G06V 10/24 (2022.01)

CPC G03F 7/705 (2013.01) [G06T 7/001 (2013.01); G06V 10/754 (2022.01); G06V 10/764 (2022.01); G06V 10/82 (2022.01); G06T 2207/20084 (2013.01); G06T 2207/30148 (2013.01); G06V 10/247 (2022.01)]

15 Claims

1. An inspection tool comprising:

an imaging system configured to capture an image of a portion of a semiconductor substrate; and

an image analysis system configured to reduce distortion in an image captured by the imaging system by determining an optimized weighting of a network comprising an encoder and a decoder, wherein the image analysis system is configured to:

for each of a plurality of test weightings, perform the following steps with the encoder and decoder operating using the test weighting:

(a) encoding, using the encoder, a reference image and a distorted image into a latent space to form an encoding;

(b) decoding the encoding, using the decoder, to form a distortion map indicative of a difference between the reference image and a distorted image;

(d) comparing the aligned image to the reference image to obtain a similarity metric; and

(e) determining a loss function which is at least partially defined by the similarity metric;

wherein the optimized weighting is determined to be the test weighting which has an optimized loss function.