Patent ID: 9052605
Filing Date: 2015-06-09
Classification: G03F

Abstract:
1. An illumination system for a lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the illumination system configured to condition a radiation beam and direct the radiation beam onto the patterning device, the illumination system comprising: a first reflective component and a second reflective component, the first reflective component being arranged to direct radiation of the radiation beam onto the second reflective component, the first reflective component comprising a plurality of movable reflective elements, each movable reflective element being moveable between at least a first position and a second position so as to change an illumination mode, and the second reflective component being associated with a pupil plane of the patterning device; and a control system arranged to set the plurality of moveable reflective elements to respective desired positions in order to effect a desired illumination mode selected from a set of predetermined illumination modes and further arranged to set at least one of the moveable reflective elements to a corrective position, different than its desired position, to effect a correction of a proximity effect in the pattern.