(Invited) Electron Transport and Strain Mapping in Ge-SixGe1-x Core-Shell Nanowire Heterostructres

Abstract

We study the role of the structural parameters of Ge-SixGe1-x core-shell nanowires, namely shell thickness and composition, on the strain and transport properties of the heterostructure. Using Raman spectroscopy in combination with lattice dynamical theory, we measure the core strain in such a NW heterostructure. We show that the measured strain increases with decreasing the core/shell thickness ratio. Using Ge-SixGe1-x core-shell nanowire heterostructures with different shell content, we investigate the effect of carrier confinement on mobility, and show that the hole mobility is markedly higher in Ge-SixGe1-x core-shell nanowires with a high Si shell content.