Patent ID: 7866330
Filing Date: 2011-01-11
Classification: G03F

Abstract:
1. A cleaning tool to clean a surface of a liquid confinement system of an immersion lithographic apparatus, the liquid confinement system having an aperture to allow passage of a beam of radiation therethrough of an immersion lithographic apparatus, the cleaning tool comprising: a sonic transducer; a reservoir configured to hold liquid between the sonic transducer and the surface to be cleaned; and a barrier positioned, in use, in the reservoir under the aperture to form a shield to sonic waves, the barrier comprising a liquid outlet that is removably attachable or sealable to a liquid confinement structure configured to confine liquid between a projection system and a substrate table of the lithographic apparatus during projection of a patterned beam onto a substrate, the liquid outlet further configured to remove liquid from the reservoir between the surface to be cleaned and the sonic transducer.