US 12,066,762 B2
On chip sensor for wafer overlay measurement
Mohamed Swillam, Wilton, CT (US); Stephen Roux, New Fairfield, CT (US); Tamer Mohamed Tawfik Ahmed Mohamed Elazhary, New Canaan, CT (US); and Arie Jeffrey Den Boef, Waalre (NL)
Assigned to ASML Holding N.V. & ASML Netherlands B.V., Veldhoven (NL)
Appl. No. 17/637,942
Filed by ASML Holding N.V., Veldhoven (NL); and ASML Netherlands B.V., Veldhoven (NL)
PCT Filed Aug. 5, 2020, PCT No. PCT/EP2020/072063
§ 371(c)(1), (2) Date Feb. 24, 2022,
PCT Pub. No. WO2021/037509, PCT Pub. Date Mar. 4, 2021.
Claims priority of provisional application 62/893,256, filed on Aug. 29, 2019.
Prior Publication US 2022/0283516 A1, Sep. 8, 2022
Int. Cl. G03F 7/20 (2006.01); G02B 6/122 (2006.01); G02B 26/08 (2006.01); G03F 7/00 (2006.01)
CPC G03F 7/70633 (2013.01) [G02B 6/1225 (2013.01); G02B 26/0833 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A sensor apparatus comprising:
a sensor chip comprising a first side and a second side opposite the first side;
an illumination system coupled to the sensor chip and configured to transmit an illumination beam along an illumination path;
a first optical system disposed on the sensor chip and comprising a first integrated optic configuration to configure and transmit the illumination beam toward a diffraction target on a substrate, disposed adjacent to the sensor chip, and generate a signal beam comprising diffraction order sub-beams generated from the diffraction target;
a second optical system disposed on the sensor chip and comprising a second integrated optic configuration to collect and transmit the signal beam from the first side to the second side of the sensor chip; and
a detector system configured to measure a characteristic of the diffraction target based on the signal beam transmitted by the second optical system.