Lithographic apparatus and device manufacturing method

摘要

A lithographic projection apparatus comprising: a radiation source for providing a projection beam of radiation; a support structure for supporting patterning means, the patterning means serving to pattern the projection beam according to a desired pattern; a substrate table for holding a substrate; a projection system for projecting the patterned beam onto a target portion of the substrate; said radiation source further comprising: an illumination system for conditioning said beam of radiation so as to provide a conditioned radiation beam so as to be able to illuminate said patterning means; said illumination system defining a plane of entrance wherein said radiation beam enters said illumination system; and a beam delivery system comprising redirecting elements for redirecting and delivering said projection beam from a radiation source to said illumination system. The lithographic projection apparatus is characterized in that the said beam delivery system comprises an imaging system for imaging said radiation beam from an object plane located at a distance from said plane of entrance to an image plane located near or at said plane of entrance. In this way the influence of laser pointing drift on both beam position and pointing drift at said entrance is highly decreased. <IMAGE>