On the nature of various growth facets at the interfaces of gold catalyzed-silicon nanowires.

Modified embedded atom method-molecular dynamics simulations have been performed to define the various growth facets at the interfaces of Au catalyzed-silicon nanowires (SiNWs). The interfacial growth facet of Au/SiNW on c-Si (111) surface has a single, planar interface, that grows parallel to the Si (111) planes. The interfacial growth facet on c-Si (211) surface has an asymmetrical, cone shape. The interface of Au/SiNW consists of two planes--the greater being {111} and the lesser being {100} planes. And finally the interfacial growth facet on c-Si (110) surface has a symmetrical, cone shape. The interface consists of two {111} planes. These findings exhibit good agreement with the previous experimental observation done with cross-sectional high-resolution transmission electron microscopy. We also predict the interfacial growth facet of Au/SiNW with NW direction (100), explaining that such a direction rarely exists due to geometrical limitations. We propose that changes in SiNW direction are caused the existence of various growth facets at the Au/SiNW interfaces.