CELL PROJECTION LITHOGRAPHY WITH SCATTERING CONTRAST

A scattering-type cell projection method is proposed and its character istics are estimated by simulation and experiment. In this method, a m ask consisting of thin scatterers and apertures is used to shape an el ectron beam. Thus, this method has advantages over the conventional ce ll projection method. First, a high aspect ratio is not necessary to f abricate the mask. Thus, the mask pattern is easily fabricated and its experimental dimensional accuracy is better than 0.2 mu m. Second, th e simulated heat deposition on the mask drastically decreases. In addi tion, simulation and experiment show good contrast of over 10(5) relat ed to using a limiting aperture to intercept scattered electrons. As a result, this method is considered to be a key technology in future el ectron beam lithography systems.