Microlithography—Key to Solid‐State Device Fabrication

Abstract
The conventional near‐u.v.‐and‐visible (310–430 nm) resist AZ1350J is found to be useful as a mask opaque material for deep‐u.v. (200–260 nm) lithography because of increased optical absorption at wavelengths below 300 nm. Only 0.2 μm is required to obtain a contrast of 100 using a Xe‐Hg arc lamp and polymethyl methacrylate(PMMA) as the photoresist. The AZ mask does not deteriorate when exposed to light if kept in a vacuum below 10−2 Torr. Otherwise, about 300 passes can be expected. Experimental printing results show 1 μm images in 1.5 μm of PMMA. Special applications in projection printing, contact printing, and the portable conformable mask technique are discussed.