Patent ID: 6014252
Filing Date: 2000-01-11
Classification: G02B,G03F,Y10S

Abstract:
A scanning ringfield lithography apparatus for patterning images on a substrate comprising:(a) a radiation source emitting extreme ultraviolet radiation of wavelengths ranging from approximately 4 to 20 nanometers;(b) a condenser;(c) a mask for generating patterned images; and(d) reflective focusing optics positioned between the mask and a substrate, comprising four reflective elements which viewed from object to image are characterized as convex, concave, convex and concave, the radius of curvature of the first reflective element is greater than about 4,000 mm, the reflective focusing optics projecting a focused image on the substrate in the shape of an arcuate slit having a constant radius of curvature between approximately 30 mm and 70 mm and an arcuate slit width between approximately 1.0 mm and 3.0 min.