LITHOGRAPHIC APPARATUS AND DEVICE MANUFACTURING METHOD

摘要

A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate is disclosed. The lithographic apparatus includes an illumination system (IL) and an outlet connected to a pumping system (78) to pump away gas from between an inner wall (64) and outer wall (62) of the illumination system (IL) or, if a radiation source (SO) is present, between the inner wall (64) of the illumination system (IL) and an inner wall (62) of the radiation source (SO).