GaAs nanowires on Si substrates grown by a solid source molecular beam epitaxy

High-quality Au-catalyzed GaAs nanowires were grown on Si substrates by vapor-liquid-solid growth in a solid source molecular beam epitaxy system. X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy reveal that the GaAs nanowires were epitaxially grown on Si substrates with uniform diameters along the nanowires. While GaAs nanowires on Si(111) and (001) substrates were mainly grown along the < 111 > direction with zinc-blende and wurtzite structures, unusual GaAs nanowires grown along < 001 > with a pure zinc-blende structure were also observed. Strong photoluminescence was observed from GaAs nanowires grown on a Si(001) substrate at room temperature. (c) 2006 American Institute of Physics.