Abstract: A lithographic projection apparatus including an illumination system configured to provide a beam of radiation, a support configured to support a patterning device, the patterning device configured to impart the beam with a pattern in its cross section, a substrate table configured to hold a substrate, a projection system configured to project the patterned radiation onto a target portion of the substrate, a plurality of level sensors for sensing a level of a substrate carried on the substrate table at a plurality of different positions, and a system for determining the position of the substrate table.

Abstract: A substrate holder to adapt a small wafer to a wafer table of a lithographic apparatus adapted to receive a larger wafer includes a plate member with a burl pattern on which the small wafer is to be placed, positioning pins to locate the small wafer and a clamp formed by a clamp ring and magnets attached to the plate member.