OPTICAL SYSTEM AND MULTI FACET MIRROR OF A MICROLITHOGRAPHIC PROJECTION EXPOSURE APPARATUS

摘要

An optical system of a microlithographic projection exposure apparatus includes a multi facet mirror having a support plate and a plurality of mirror facets. Each mirror facet includes a mirror substrate and a reflective coating applied thereon, and is attached to the support plate. Actuators are provided that induce a deformation of the support plate. The deformation changes the orientation and/or position, but not the shape, of at least two mirror facets. In this way aberrations can be corrected.