Illumination system for an EUV projection lithographic projection exposure apparatus

Abstract

An illumination system for an EUV projection lithographic projection exposure apparatus comprises an EUV light source, which generates an output beam of EUV illumination light with a predetermined polarization state. An illumination optical unit guides the output beam along an optical axis, as a result of which an illumination field in a reticle plane is illuminated by the output beam. The light source comprises an electron beam supply device, an EUV generating device and a polarization setting device. The EUV generating device is supplied with an electron beam by the electron beam supply device. The polarization setting device exerts an adjustable deflecting effect on the electron beam for setting the polarization of the output beam. This results in an illumination system, which operates on the basis of an electron beam-based EUV light source and provides an output beam, which is improved for a resolution-optimized illumination.

Dependencies are inferred from the claim text.