Theoretical calculation of electron mobility in HgCdTe

Abstract

The low field electron mobility in n-type HgCdTe is calculated by using the relaxation time approximation method. Scattering mechanisms considered in the analysis are ionized impurity, electron–hole, alloy, and polar optical-phonon (two types) scatterings. The calculation also retains band-structure effects such as nonparabolic conduction band, electron wave function admixture, and velocity degradation as the electron energy increases. Furthermore, degeneracy is incorporated without approximation. For polar optical-phonon momentum relaxation time, we employ a model that can be applicable at low temperature, when the thermal energy is lower than the optical-phonon energy. The calculation results for drift mobility are in good agreement with the Monte Carlo results. The effects of donor level, compensation, and ionicity of impurity on Hall mobility are also presented.