ASML Holding N.V.
Patterning device cooling system and method of thermally conditioning a patterning device

Abstract:

A patterning device cooling system for thermally conditioning a patterning device of a lithographic apparatus, wherein the patterning device in use, is being irradiated by exposure radiation, wherein the patterning device cooling system comprises: a thermal conditioner configured to thermally condition the patterning device; and a controller configured to control the thermal conditioner to thermally condition the patterning device dependent on an amount of the exposure radiation absorbed by the patterning device.