Patent ID: 7468521

Claim:
A lithographic apparatus comprising: a radiation system configured to provide a beam of radiation from radiation emitted by a radiation source, the radiation system comprising a contaminant trap configured to trap material emanating from the radiation source and/or a collector configured to collect the beam of radiation, the contaminant trap and/or the collector comprising an element arranged in the path of the radiation beam on which the material that emanates from the radiation source can deposit during propagation of the radiation beam in the radiation system, at least a part of the element disposed in the path of the radiation beam having a surface that has a highly specular grazing incidence reflectivity to reduce the absorption of the radiation beam in a direction of propagation of the radiation beam substantially non-parallel to the surface of the element, so that a thermal load experienced by the element is reduced; an illumination system configured to condition the radiation beam; a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam; a substrate table constructed to hold a substrate; and a projection system configured to project the patterned radiation beam onto a target portion of the substrate.