High density and patternable growth of silicon, germanium and alloyed SiGe nanowires by a rapid anneal protocol

We report the formation of silicon, germanium and alloyed Si_1-xGe_x nanowires by direct pyrolysis of liquid precursors on a heated substrate in an inert environment. The nanowires form in high density on the substrate with a fast reaction time. We use SEM, HRTEM, EDX-STEM, and Raman spectroscopy to carry out an in depth study into the population distribution of Si_1-xGe_x nanowires. The method was sufficiently adaptable to pattern the nanowire growth using standard dry film lithography techniques. Additionally, we further show that direct writing with a copper metal pen deposited sufficient catalyst to allow localised nanowire growth constrained to the treated areas.