Selective and directed growth of silicon nanowires by tip-enhanced local electric field

We present a method to trigger highly selective and directed growth of individual silicon nanowires based on an electrically biased atomic force microscope (AFM) tip. The biased tip affects the nanowire growth behavior right from the initial stage. In particular, the locally intensified electric field at the AFM tip apex assists the dissociation of the precursor gas molecules and exerts augmented electrostatic force on the catalyst/NW assembly. Therefore, the electrically biased tip can be a candidate tool for the direct synthesis/integration of semiconductor nanomaterials on temperature-sensitive substrates.