Electrode flatness requirements for cathode projection microfabrication systems

One of the most promising techniques for large-area submicron electron-beam lithography is the Cathode Projection Microfabrication System. According to published reports, these systems suffer from excessive image distortion. This distortion is partly caused by nonflat photocathodes and silicon wafer anodes. In this paper, a universal curve is obtained which quantitatively predicts and explains the image distortions which result from surface topography. Apparently, the practicality of multilayer submicron lithography in such systems is presently threatened by a requirement that nonreproducible wafer surface waviness be less than 2-3 microns.