Syntaxial growth of Ge/Mn-germanide nanowire heterostructures.

We report the growth of free-standing one-dimensional Ge/Mn-germanide nanowire heterostructures by chemical vapor deposition and provide a detailed description of the growth mechanism. Self-assembled manganese-germanide particles seed the growth of Ge nanowires (GeNWs) and simultaneously elongate along a parallel axis, resulting in syntaxial growth of the two phases. The GeNW growth is limited by GeH 4 decomposition, whereas the germanide growth is limited by reaction of Mn at the growth interface. This syntaxial growth mechanism provides a novel route to axial metal/semiconductor nanowire heterostructures.