Patent ID: 6768539
Filing Date: 2004-07-27
Classification: G03F

Abstract:
A lithographic projection apparatus comprising:a patterning structure which can be used to pattern a projection beam according to a desired pattern; a substrate table to hold a substrate; a projection system to image the patterned beam onto a target portion on a first side of the substrate; an alignment system, located on a same side of the substrate as the projection system, to align a pattern of the patterning structure with an alignment mark provided on the substrate, using alignment radiation; and an optical system to transmit an image of the alignment mark from a side of the substrate opposite the target portion for use by the alignment system, wherein the optical system is arranged to provide an image of said alignment mark in a plane which is substantially perpendicular to an optical axis of the alignment system, the image being located outside of a perimeter of the substrate.