A COVER FOR SHIELDING A PORTION OF AN ARC LAMP

摘要

A cover for shielding a part of arc lamp is provided to prevent a heating effect of a thermocouple by reflecting a radiation beam reflected from a reflecting surface. An illumination system(IL) is formed to condition a radiation beam(PB). A support structure(MT) is formed to support a patterning device(MA) and is connected to a first positioning device(PM) in order to position accurately the patterning device with respect to an item. A substrate table(WT) is formed to hold a substrate(W) and is connected to a second positioning device(PW) in order to position accurately the substrate with respect to the item. A projection system(PL) is configured to image a pattern applied to the radiation beam by the patterning device onto a target part of the substrate.