COMBINED AFM AND LASER LITHOGRAPHY ON HYDROGEN-PASSIVATED AMORPHOUS-SILICON

We report a novel combination of AFM lithography and laser direct writ ing on hydrogen-passivated amorphous silicon surfaces to fabricate com bined silicon milli-, micro- and nanostructures. Selective oxidation i s performed by focusing a laser beam (lambda = 458 nm) on a hydrogen-t erminated silicon surface, forming the millimetre-size contact pads fo r connection of nanometre-scale patterns. The nanostructures are made by electric-field-enhanced oxidation using a contact mode AFM equipped with a metal-coated tip. Both techniques are based on selective oxida tion of hydrogen-passivated amorphous silicon, where the oxide is used as an etch mask in a single etch step. The lithographic process has a lso been demonstrated using a reflection mode scanning near-field opti cal microscope with an uncoated fiber probe. (C) 1996 Academic Press L imited