Spatial uniformity varier for microlithographic illuminator

摘要

A microlithographic projection imager has an illuminator system that is adjustable for the uniformity of spatial intensity of the illumination delivered to the wafer plane. This uniformity adjustment can compensate for factors tending to deviate the illumination from uniformity. The uniformity adjusting member is preferably refractive and axially movable next to a pupil of the illuminator.