Energy-Band Structure of Strained Indirect Gap Semiconductor: A k. p Method

摘要

A strain Hamiltonian H_(st), associated with a sps~* k. p Hamiltonian H_(kp), is used to describe the valence band and the first two conduction bands of a strained indirect semiconductor. H_s, takes into account the Bir-Pikus parameters (a, b) used up to now to describe only the Brillouin zone center. The H_(kp)+H_(st), Hamiltonian allows one to calculate the energy dispersion all over the Brillouin zone. The method is applied to Si strained on Si_(1-x)Ge_x alloy. We do not use the local (in k space) deformation potentials Ξ_u and Ξ_d conventionally used in indirect gap semiconductor to describe the conduction band. The energy band gap, the conduction bands split into the four equivalent in-plane valleys Δ_4 and the two valleys along the growth direction Δ_2 which result from the above H_(kp)+H_(st) Hamiltonian are in very good agreement with other publications.