Doping-dependent nanofaceting on silicon nanowire surfaces

Silicon nanowires with axially varying n- and p-doping were grown by the vapor-liquid-solid approach using gold as the catalyst. The nanowire sidewalls exhibit periodic nanofaceting, which is found to be dopant-dependent. It is shown that the nanofaceting occurs during the enhanced sidewall growth that arises when the diborane dopant gas is introduced. The nanowires are axially oriented along ⟨111⟩, and the crystallographic planes on which the nanofaceting occurs are determined to be {111} and {100}.