Projection exposure system as well as a process for compensating image defects occuring in the projection optics of a projection exposure system, in particular for microlithography

摘要

A projection exposure system, in particular for microlithography, serves for the generation of an image in an image plane of an object arranged in an object plane. The system comprises a light source that emits a projection light bundle. The system also comprises a projection optics arranged in the optical path between the object plane and the image plane as well as at least one optical correction component arranged in the projection light optical path in front of the image plane. In order to change the optical image properties this component is coupled to at least one correction manipulator so that an optical surface of the optical correction component illuminated by the projection light bundle is moved at least regionally. In this connection the correction manipulator operates together with a correction sensor device. The correction sensor device comprises a light source that emits at least one measuring light bundle. This light bundle passes through at least a part of the projection optics and lie sin front of the entry point to and after the exit from the projection optics outside the projection light bundle. The correction sensory device also has a position-sensitive correction sensor element for the detection of the wave front of the at least one measuring light bundle. By means of the correction sensor device a correction of image defects of the projection optics is ensured without the loss of projection light.