Patent ID: 7352434
Filing Date: 2008-04-01
Classification: G03F

Abstract:
1. A lithographic projection apparatus, comprising: a substrate table configured to hold a substrate; a projection system configured to project a patterned beam of radiation onto a target portion of the substrate and having an optical axis; a liquid supply system configured to provide an immersion liquid on less than an entire surface of the substrate in a space between the projection system and the substrate, wherein at least part of the liquid supply system is free to move in the direction of the optical axis and/or rotate about at least one axis perpendicular to the optical axis; a measurement system configured to determine a height of at least part of the liquid supply system above the surface of the substrate or configured to determine a surface height of the substrate; and a control system configured to control the height of at least part of the liquid supply system above the surface of the substrate using the determined height.