PROJECTION LENS, MICROLITHOGRAPHIC PROJECTION EXPOSURE SYSTEM AND METHOD FOR PRODUCING A SEMICONDUCTOR CIRCUIT

摘要

The invention relates to a projection lens for a microlithographic projection exposure system (10) comprising several optical elements (M1 to M6) and temperature adjustment means (34, 36) for achieving at least an approximately homogeneous temperature in at least one of the optical elements (M6). Said optical element(s) (M6) contain(s) a material, whose thermal expansion co-efficient ( alpha ) has a minimum value at a zero crossover temperature (T0). The temperature adjustment means (34, 36) enable at least the approximate zero crossover temperature (T0) to be achieved at least in one region of the material, in particular in a region in the vicinity of a surface (46) that is exposed to a projection light (161, 162). A vanishing or minimal value thermal expansion coefficient at the temperature T0 is advantageous, as neither smaller temperature fluctuations of the entire optical element (M6), nor inhomogeneities of the temperature distribution inside the optical element (M6) can lead to an appreciable thermal deformation of the element (M6) and thus to aberrations.