US 9,811,001 B2
Method and apparatus for inspection and metrology
Peter Danny Van Voorst, Nijmegen (NL); Duygu Akbulut, Eindhoven (NL); Koos Van Berkel, Waalre (NL); Jeroen Johan Maarten Van De Wijdeven, Eindhoven (NL); and Ferry Zijp, Nuenen (NL)
Assigned to ASML NETHERLANDS B.V., Veldhoven (NL)
Filed by ASML NETHERLANDS B.V., Veldhoven (NL)
Filed on Mar. 9, 2016, as Appl. No. 15/65,674.
Claims priority of application No. 15158677 (EP), filed on Mar. 11, 2015.
Prior Publication US 2016/0266503 A1, Sep. 15, 2016
Int. Cl. G01B 11/04 (2006.01); G02B 7/02 (2006.01); G03B 27/32 (2006.01); G03B 27/74 (2006.01); G03F 7/20 (2006.01); G02B 21/00 (2006.01); G01N 21/956 (2006.01); G01B 11/00 (2006.01); G02B 27/09 (2006.01)
CPC G03F 7/70483 (2013.01) [G01B 11/00 (2013.01); G01N 21/956 (2013.01); G02B 21/0016 (2013.01); G02B 27/0988 (2013.01); G03F 7/70625 (2013.01); G03F 7/70633 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of position control of an optical component relative to a surface, the method comprising:
obtaining a first signal by a first position measurement process, the obtaining the first signal comprising:
providing radiation through the optical component to reach the surface,
blocking at least part of the radiation redirected by the surface to cause a change of shape or size of illuminated area in a pupil, or conjugate thereof, as a function of change in position between the optical component and the surface, and
detecting the redirected radiation of the illuminated area to produce a signal used to derive the first signal;
controlling relative movement between the optical component and the surface for a first range of motion using the first signal;
obtaining a second signal by a second position measurement process different than the first position measurement process; and
controlling relative movement between the optical component and the surface for a second range of motion using the second signal, the second range of motion being nearer the surface than the first range of motion.