Control of growth orientation for epitaxially grown ZnSe nanowires

Abstract
ZnSe nanowires (NWs) were grown on (111), (100), and (110)-oriented GaAs substrates by molecular-beam epitaxy via the vapor-liquid-solid reaction. The size dependence of NW growth orientation was studied by varying the Au catalyst size. Through detailed transmission electron microscopy studies, it was found that ⟨111⟩ orientation is the growth direction for NWs with size 30nm , while NWs with size around 10nm prefer to grow along the ⟨110⟩ direction, with a small portion along the ⟨112⟩ direction. These observations have led to the realization of vertical ZnSe NWs with size around 10nm grown on a GaAs(110) substrate.