Lithographic apparatus and device manufacturing method

摘要

An immersion lithographic apparatus is provided with a liquid confinement structure which defines at least in part a space configured to contain liquid between the projection system and the substrate. In order to reduce the crossing of the edge of the substrate which is being imaged (which can lead to inclusion of bubbles in the immersion liquid), the cross-sectional area of the space in a plane parallel to the substrate is made as small as possible. The smallest theoretical size is the size of the target portion which is imaged by the projection system. In an embodiment, the shape of a final element of the projection system is also changed to have a similar size and/or shape in a cross-section parallel to the substrate to that of the target portion.

主权项

1. A lithographic apparatus comprising:
a substrate table constructed to hold a substrate; a projection system configured to project a patterned radiation beam onto a target portion of a surface of the substrate and having an element immediately adjacent the substrate, the element having a cross-sectional shape in a plane substantially parallel to the substrate similar to the shape of the target portion; and a liquid confinement structure having a surface at least in part defining a space configured to contain a liquid between the projection system and the substrate, wherein a bottom surface of the liquid confinement structure is closer to the substrate table than a bottom surface of the element, and in a plane substantially parallel to the surface of the substrate, an inner boundary of the liquid confinement structure that surrounds a path of the patterned radiation beam to the substrate defines an aperture, the aperture having a shape that has a plurality of sides and which substantially conforms in shape to the shape of the target portion.