US 12,140,872 B2
Optical designs of miniaturized overlay measurement system
Mohamed Swillam, Wilton, CT (US); Tamer Mohamed Tawfik Ahmed Mohamed Elazhary, New Canaan, CT (US); Stephen Roux, New Fairfield, CT (US); and Yevgeniy Konstantinovich Shmarev, Campbell, CA (US)
Assigned to ASML Holding N.V., Veldhoven (NL)
Appl. No. 17/796,640
Filed by ASML Holding N.V., Veldhoven (NL)
PCT Filed Jan. 21, 2021, PCT No. PCT/EP2021/051340
§ 371(c)(1), (2) Date Jul. 29, 2022,
PCT Pub. No. WO2021/151775, PCT Pub. Date Aug. 5, 2021.
Claims priority of provisional application 62/967,106, filed on Jan. 29, 2020.
Prior Publication US 2023/0059471 A1, Feb. 23, 2023
Int. Cl. G03F 7/00 (2006.01); G03F 9/00 (2006.01)
CPC G03F 7/70633 (2013.01) [G03F 9/7088 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A sensor apparatus, comprising:
a beam shaping system configured to shape an illumination beam generated from an illumination system and to generate a flat top beam spot of the illumination beam;
a beam projection system configured to project the flat top beam spot toward a target on a substrate; and
a signal detection system configured to collect a signal beam comprising diffraction order sub-beams generated from the target and to measure a characteristic of the target based on the collected signal beam,
wherein the beam shaping system comprises:
a collimator lens, followed by a spatial light modulator, followed by a focusing lens; or
a photonic element coupled to a photonic crystal fiber, followed by a collimator lens, followed by a focusing lens; or
a collimator lens followed by an aspheric beam shaper.