Lithographic apparatus and device manufacturing method

摘要

A lithographic apparatus includes a projection system configured to project a patterned radiation beam onto a target portion of a substrate. The projection system has a final element. The apparatus also includes a barrier member surrounding a space between the projection system and, in use, the substrate, to define in part with the final element a reservoir for liquid. The barrier member is spaced from the final element to define a gap therebetween. The apparatus further includes a deformable seal between a radially outer surface of the final element and a radially outer surface of the barrier member. The deformable seal is configured to substantially prevent a gas from flowing past the seal towards or away from the reservoir of liquid.

主权项

1. A lithographic apparatus comprising:
a projection system configured to project a patterned radiation beam onto a target portion of a substrate, the projection system having a final element; a barrier member surrounding a space between the projection system and, in use, the substrate, to define in part with the final element a reservoir for a first liquid, the barrier member being spaced from the final element to define a gap therebetween; and a seal between a radially outer surface of the final element and a radially outer surface of the barrier member, the seal being configured to substantially prevent a gas from flowing past the seal towards or away from the reservoir of first liquid, the seal comprising a second liquid different from the first liquid, and the second liquid arranged to be located at least in part between a substantially horizontal surface of the barrier member and a facing surface of the final element and/or between a substantially horizontal surface of the final element and a facing surface of the barrier member.