Electronic band structure calculations for biaxially strained Si, Ge, and III-V semiconductors

Electronic band structure and effective masses for relaxed and biaxially strained Si, Ge, III-V compound semiconductors (GaAs, GaSb, InAs, InSb, InP) and their alloys (In(x)Ga(1-x)As, In(x)Ga(1-x)Sb) on different interface orientations, (001), (110) ,and (111), are calculated using nonlocal empirical pseudopotential with spin-orbit interaction. Local and nonlocal pseudopotential parameters are obtained by fitting transport-relevant quantities, such as band gap and deformation potentials, to available experimental data. A cubic-spline interpolation is used to extend local form factors to arbitrary q and to obtain correct workfunctions. The nonlocal and spin-orbit terms are linearly interpolated between anions and cations for III-V semiconductors. The virtual crystal approximation is employed for the In(x)Ga(1-x)As and In(x)Ga(1-x)Sb alloys and deformation potentials are determined using linear deformation-potential theory. Band gap bowing parameters are extracted using least-square fitting for relaxed alloys and for strained In(x)Ga(1-x)As on (001) , (110), and (111) InP. The dependence on biaxial strain of the electron and hole effective masses at the symmetry points Gamma, X, and L exhibits a continuous variation at Gamma and L but sudden changes appear at Delta minima caused by the flatness of the dispersion along the Delta line near the minimum. (C) 2010 American Institute of Physics. [doi:10.1063/1.3437655]