Patent ID: 8670103

Claim:
A cleaning method used in a liquid immersion exposure apparatus, the method comprising: placing an object to perform a cleanup process such that a surface of the object is opposite to a final surface of an optical system of the exposure apparatus in which a wafer is exposed with an exposure beam via the final surface of the optical system through an immersion liquid supplied from a nozzle member of the exposure apparatus during an immersion lithography process; filling a space adjacent the optical system with a liquid supplied from the nozzle member during the cleanup process; and moving the object under the optical system relative to the optical system in a direction substantially parallel to the final surface of the optical system during the cleanup process, while the liquid is in contact with the final surface of the optical system and the surface of the object; wherein bubbles are generated in the liquid to clean a member of the apparatus which is in contact with the liquid during the cleanup process, wherein the surface of the object, but not the wafer, contacts the liquid during the cleanup process.