Electric field and surface step assisted Cu3Si nanowire growth by reactive deposition epitaxy

Abstract

Metal silicide nanowires such as copper silicide have been shown to self-assemble into nanowire and nanoisland structures on the surface of silicon substrates. The self-assembly of these nanostructures occurs during reactive deposition epitaxy (RDE). It was observed that varying the surface step orientation of a sample with respect to an applied electric field had a direct influence on the length of vicinal steps and the length of self-assembled nanowires grown using RDE. Si(110) substrates were diced so that the [110] surface step directions with respect to the applied electric field direction were parallel, perpendicular, and 45°. All samples were prepared using the same preparation and Cu deposition parameters. Under the same growth parameters perpendicular orientation samples resulted in the longest thinnest nanowires, parallel orientation samples had short wider wires, whilst the 45° orientation samples had wire dimensions slightly larger than those on the parallel orientation samples.