Novel wet chemical etch for nanostructures based on II-VI compounds

A simple wet chemical etch which produces stable and oxide-free surfaces of ZnSe is described. The etchant, a low pH solution of H2SO4:H2O2:H2O, reacts with ZnSe producing an amorphous layer of Se which grows into the semiconductor. The Se layer is then dissolved in aqueous (NH4)(2)S resulting in a S-passivated surface. The S-passivated layer is volatile and can be desorbed by heating the sample to 300 degrees C. The efficacy of this process is demonstrated by the formation of 20 nm wide quantum wires of CdZnSe/ZnSe with good optical properties. (C) 1997 American Institute of Physics.