Method of operating a lithographic apparatus, lithographic apparatus, method of manufacturing a device, and device manufactured thereby

摘要

A method of operating a lithographic projection apparatus including forming a spot of radiation at the wafer level using a pinhole at reticle level. A sensor is defocused with respect to the spot such that it is spaced apart from the wafer level. The sensor is scanned beneath the spot to measure the angular intensity distribution of radiation at the spot and to determine the intensity distribution at the pupil plane of the projection lens system.