LITHOGRAPHIC APPARATUS, DEVICE FABRICATING METHOD, DEVICE FABRICATED THEREBY AND COMPUTER PROGRAM

摘要

PURPOSE: A lithographic apparatus is provided to compensate for the transmission loss due to surface contamination of a mask MA by predicting the transmission loss as a function of position on the mask and time and by using an apparatus capable of adjusting the beam intensity across the length of an exposure field. CONSTITUTION: A radiation system supplies a projection beam of radiation. A support structure supports a patterning unit functioning to pattern the projection beam according to a predetermined pattern. A substrate is held by a substrate table. A projection system projects the patterned beam onto a target part of the substrate. A prediction unit predicts an unwanted intensity loss of the patterned beam caused by the surface contamination of the patterning unit, based on the history of the patterning unit. A compensation unit responds to the predicted intensity loss so as to compensate for the predicted intensity loss.