METHOD OF OPERATING A MICROLITHOGRAPHIC PROJECTION EXPOSURE APPARATUS

摘要

A method of operating a microlithographic projection exposure apparatus comprising the steps of : providing an illumination system (12) having an illumination pupil plane (38); providing a projection objective (18) having an objective pupil plane (58), which is optically conjugate to the illumination pupil plane (38); providing a mask (14) containing structures (15); determining a target spatial irradiance distribution of projection light (28) in the illumination pupil plane (38); illuminating a portion of the mask (14) with projection light that produces in the illumination pupil plane (38) a modified spatial irradiance distribution, wherein there is an excess area (70) in the illumination pupil plane which is irradiated in the modified spatial irradiance distribution, but is not irradiated in the target spatial irradiance distribution; and stopping those light rays (36c), which pass the excess area (70) in the illumination pupil plane (38), from reaching a light sensitive surface (20) by using a stop (66; 166; 266) that is arranged in the projection pupil plane (58).