Self-assembled epitaxial silicon nanowires grown along easy-glide directions on Si(001)

Epitaxial silicon nanowires (SiNWs) were grown along < 110 > directions on Si(001) at 1100 degrees C via a convenient annealing process catalysed by Au nanoparticles. The density and size of Au nanodots have been controlled by nanosphere lithography. The SiNWs are devoid of structural defects. A clean Si wafer, with the polished side facing down and in close contact with the substrate, was also found to be essential to supply and keep Si vapour pressure high near the substrate and prevent the oxidation of the Si NW during growth.