Formation of Ge-based nanowires for nanoelectronic applications by vapor-liquid-solid mechanism

Using vapour-liquid-solid mechanism, we have grown Ge and composition modulated Ge:SnO₂ nanowires on gold coated silicon substrates with diameter distribution ranging from 30-100 nm, and length more than tens of micrometers. The outer sheath of pure Ge nanowires consists of GeO₂ as revealed from the XRD and TEM analyses. Raman spectra of the as-grown nanowires exhibit a blue shift, which is attributed to the compressive strain in the wires. The formed T-junction Ge:SnO₂ axial nanowire heterostructure is attractive for novel optical and electronic devices.