LITHOGRAPHIC PROJECTION APPARATUS AND METHOD OF COMPENSATING PERTURBATION FACTORS

A lithographic projection apparatus including a support structure configured to support a patterning device, the patterning device configured to impart a beam of radiation with a pattern in its cross-section; a substrate holder configured to hold a substrate; a projection system configured to expose the patterned beam of radiation on a target portion of the substrate; and a system configured to compensate one or more perturbation factors by providing an additional beam of radiation to be exposed on the target portion of the substrate, the additional beam of radiation being imparted in its cross-section with an additional pattern which is based on the pattern of the patterning device and on lithographic projection apparatus property data, the lithographic projection apparatus property data characterizing a level and nature of one or more systematic perturbation factors of different lithographic apparatus.