Residual pupil asymmetry compensator for a lithography scanner

摘要: A uniformity correction system may be used as an actuator for the of asymmetry scan-integrated illumination pupil fill that varies in non-scanning direction a lithography system. Instead minimizing asymmetric opaque element insertion, elements are inserted into beam to introduce additional beam. The compensating substantially nulls original asymmetry. To asymmetry, first can moved or out tandem with second, opposing element. Iterative feedback both and ensure simultaneously optimized.