Patent ID: 8947629
Filing Date: 2015-02-03
Classification: G03F

Abstract:
1. An apparatus to clean an immersion lithographic projection apparatus, comprising: a sonic transducer having a sonic wave emitting surface facing upward and non-perpendicular to, in use, a surface of the immersion lithographic apparatus to be cleaned other than a surface of the transducer and configured to clean the surface of the immersion lithographic apparatus, wherein, in use, a perpendicular of the sonic wave emitting surface intersects the surface; a liquid supply system constructed and arranged to supply liquid between the sonic transducer and the surface to be cleaned; and a cleaning liquid outlet configured to accommodate a cleaning fluid outflow during application of sonic waves to the surface to be cleaned, the cleaning liquid outlet positioned substantially in the center of an area to which the liquid is provided and arranged such that the sonic wave emitting surface extends around or on at least two opposite sides of the outlet and extends substantially perpendicularly to the direction of the cleaning fluid outflow.