LITHOGRAPHIC APPARATUS AND DEVICE MANUFACTURING METHOD

摘要

A lithographic apparatus comprising an optical column capable of creating a pattern on a target portion of a substrate is disclosed. The optical column may have a self emissive contrast device configured to emit a beam, and a projection system configured to project the beam onto the target portion. The apparatus may also have an actuator to move the optical column or a part thereof with respect to the substrate. The apparatus may be constructed to reduce the optical effect of density variation in a medium around the moving part of the optical column on the beam.