Patent ID: 6879374
Filing Date: 2005-04-12
Classification: G03F

Abstract:
1. A device manufacturing method, said method comprising: positioning a reflective patterning structure to reflect at least a portion of a beam of radiation as a patterned beam of radiation having a pattern in its cross-section; and using a projection system to project the patterned beam of radiation to form an image on a target portion of a layer of radiation-sensitive material that at least partially covers a substrate; and obtaining a distortion value of the reflective patterning structure, wherein said positioning includes at least one among shifting and tilting a nominal reflective surface of the reflective patterning structure with respect to a nominal object plane of the projection system according to the distortion value, and wherein said obtaining a distortion value includes using a measurement beam to determine a position of a back surface of the reflective patterning structure.