| CPC H01L 21/6875 (2013.01) [G03F 7/70341 (2013.01); G03F 7/707 (2013.01)] | 20 Claims |

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1. A substrate holder for use in a lithographic apparatus and configured to support a substrate, the substrate holder comprising:
a main body having a main body surface;
a plurality of first burls projecting from the main body surface, each first burl having a distal end surface configured to support the substrate;
a first seal member projecting from the main body surface at an edge region of the main body and having a distal surface arranged to be spaced apart by a first gap from the substrate when the substrate is supported by the plurality of burls, the first seal member surrounding the plurality of first burls;
a plurality of second burls arranged outwards, relative to a central portion of the main body, of the first seal member, each second burl having a distal end surface configured to support the substrate;
a second seal member projecting from the main body surface at the edge region of the main body and having a distal surface arranged to be spaced apart by a second gap from the substrate when the substrate is supported by the plurality of burls, the second seal member surrounding the first seal member and the plurality of second burls and the first gap is arranged to be fluidly connected to the second gap when the substrate is supported by the plurality of burls; and
a plurality of extraction openings formed in the main body for the extraction of fluid into the main body from between the main body and the substrate,
wherein the substrate holder is configured such that an under pressure at the extraction openings is stronger than that at the plurality of first burls, causing an outward flow over the distal surface of the first seal member.
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