In-situ observation of ⟨110⟩ oriented Ge nanowire growth and associated collector droplet behavior

Using in-situ microscopy, we show that germanium nanowires can be grown by a vapor-liquid-solid process in < 110 > directions both on Ge(100) and Ge(111) substrates if very low supersaturation in the collector droplet is ensured, This can be provided if thermal evaporation is utilized. Such a behavior is also in agreement with earlier chemical vapor deposition experiments, where < 110 > oriented wires were obtained for very small wire diameters only. Our conclusions are supported by in-situ observations of nanowirc kinking towards < 111 > direction occurring more frequently at higher evaporation rates. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3647774]