Patent ID: 7027132
Filing Date: 2006-04-11
Classification: G03F

Abstract:
1. A lithographic apparatus comprising: an illumination system for conditioning a beam of radiation; an article support for supporting a substantially flat article to be placed in a beam path of said beam of radiation, said article support comprising a plurality of supporting protrusions, said plurality of supporting protrusions defining a support zone for providing a substantially flat plane of support; a backfill gas feed arranged in said support zone for providing a backfill gas that flows to a backside of said article when supported by said article support, said backfill gas feed providing an improved thermal conduction between said article and said article support, said support zone being surrounded by a boundary zone having a reduced height relative to said plane of support so that said backfill gas flow is permitted to exit said support zone; a tunable clamp for clamping said article to said article support; and a flow measuring system that measures the outflow of said backfill gas, the tunable clamp being operatively coupled to said flow measuring system to tune said clamping based on the measured outflow.