Stop for arrangement in a constriction of an euv illumination beam

Abstract

A stop is configured to be arranged in a constriction of an EUV illumination light beam between an EUV light source for EUV illumination light and an EUV illumination optical unit. The stop has a beam entrance section, a beam exit section and an intervening beam tube section. The entrance section has a cross section that decreases in the propagation direction of the EUV illumination light beam. The cross section of the exit section increases in the propagation direction. The cross section of the tube section is constant. An inner wall of the beam tube section is embodied as reflective for the EUV illumination light. The result is a stop that can have a defined predetermination of the illumination light beam in conjunction with a good thermal loading capacity of the stop.

Dependencies are inferred from the claim text.