Patent ID: 7982850

Claim:
A lithographic projection apparatus, comprising: a substrate table configured to hold a substrate and movable in a scanning direction; a projection system configured to project a patterned beam of radiation onto a target portion of the substrate; and a liquid confinement structure extending along at least a part of a boundary of a space between the projection system and the substrate table, wherein, when liquid is in the space, the cross-sectional area of the liquid in the space is smaller than the area of the substrate, the liquid confinement structure positioned adjacent a final surface of the projection system and comprising: a first inlet to supply liquid, through which the patterned beam is to be projected, to the space, a first outlet to remove liquid after the liquid has passed under the projection system, and a second inlet formed in a face of the structure, the face arranged to oppose a surface of the substrate onto which the patterned beam is projected, and the second inlet located radially outward, with respect to an optical axis of the projection system, of the space to supply gas to push liquid to substantially prevent liquid from passing radially outward of the second inlet.