Patent ID: 9091940
Filing Date: 2015-07-28
Classification: G03F

Abstract:
1. A lithographic projection method comprising: filling a space between a projection system and a surface of a substrate supported by a substrate table, with a liquid during exposure of the substrate using a liquid confinement member which is positioned adjacent a final surface of the projection system, the liquid confinement member extending along at least a part of the boundary of the space and the liquid in the space having a cross-sectional area smaller than the area of the substrate, wherein the member has an open aperture in a bottom surface of the member, the open aperture being in a part of the member below the final surface of the projection system and above the substrate table, the open aperture having a cross-sectional width smaller than a cross-sectional width of the substrate, the open aperture configured to allow the liquid to flow therethrough between above the open aperture and below the open aperture, and the open aperture configured to allow an exposure beam to pass therethrough; projecting an image onto the substrate by the projection system during the exposure; supplying a gas from an inlet of the liquid confinement member to push the liquid to substantially prevent the liquid from passing radially outward of the inlet, the inlet being arranged to oppose the surface of the substrate during the exposure; and removing fluid via an outlet of the liquid confinement member, that is located further outward from the space than is the inlet, the outlet being arranged to oppose the surface of the substrate during the exposure.