Valence band structure and hole effective mass of uniaxial stressed Germanium

The valence band structure and hole effective mass of Germanium under uniaxial [110] stress were investigated by using six-band k⋅p theory coupled with deformation potential theory. The valence band edge energy level shifting, splitting, and effective mass change were calculated for different uniaxial [110] stress configurations. The results show that the degenerate of valence band edge energy levels was lifted and the shape of valence bands was distorted in comparison to unstressed case. The effective mass for the top band along the [110] direction is the lowest compared with other directions under uniaxial [110] compressive stress. The isotropic effective masses for the top and second bands in unstressed case, our calculated results show good agreement with the available experimental values. The obtained splitting energy between the top and the second bands, direction effective mass, and isotropic effective mass can provide valuable reference for the calculation of other physical parameters of uniaxial stressed Germanium.