High-speed low-power x-ray lithography

High-speed low-power x-ray lithography has been accomplished using 8.34-Å radiation excited by a 75-W electron beam. Incident x-ray flux at the polymer film was 50 μW/cm2. Exposure was through a 3.4-μm-thick silicon mask substrate with patterns in a 4000-Å-thick gold film. Resist thickness was 4000–5000 Å. Both positive and negative resists have been used. Exposure times were 4 min for both poly(diallyl orthophthalate) and poly(butene-1 sulfone), 100 sec for poly(glycidyl methacrylate-co-ethyl acrylate), and 15 sec for epoxidized polybutadiene.