By combining atom lithography and plasma etching technology in a two-step p
rocess, we demonstrate the transfer of sharp edged structures into silicon
with a depth of 580 nm and an inclination of better than 86 degrees. A self
-assembled monolayer resist deposited on a An-coated Si surface is damaged
by a beam of metastable helium atoms through a physical mask. A wet etching
process removes Au in the damaged regions, resulting in an intermediate ma
sk of patterned Au on Si. Low-pressure plasma etching is then used to trans
fer the pattern of the Au mask into the Si. This plasma etching process sho
ws a selectivity greater than 19 with respect to the Au mask. (C) 1998 Amer
ican Vacuum Society. [S0734-211X(98)14206-3].