Patent ID: 6226346
Filing Date: 2001-05-01
Classification: G02B,G03F

Abstract:
A scanning ring field lithography apparatus for patterning images on a substrate comprising:a radiation source emitting extreme ultraviolet radiation of wavelengths ranging from approximately 4 to 20 nanometers;a reflective mask for generating patterned images at the substrate;reflective focusing optics positioned between the mask and the substrate, comprising four reflective elements which listed from mask to substrate are characterized as convex, concave, convex and concave, arranged such that the convex first reflective element is positioned in closer proximity to the substrate than the convex third reflective element, wherein the reflective focusing optics project a focused image on and telecentric at the substrate in the shape of an arcuate slit having a width between approximately 0.5-3.0 mm, and wherein the reflective focusing optics are characterized by a balanced static centroid distortion curve across the width of the arcuate slit and a numerical aperture of at least about 0.1.