On the mobility of holes in deformed semiconductors

Abstract

Abstract The scattering of free holes at dislocations is calculated by a Born approximation. The scattering potential is composed of a coulomb interaction with the charged dislocation core and an interaction with the strain field via the deformation potential. Combination of these two mechanisms with phonon scattering in the transport equation leads to a modification of Matthiessen's rule for the total mobility. Comparison with mobility data on deformed p‐Ge shows that the modifications are essential for a quantitative agreement between theory and experiment. A sharp peak in the second derivative of the mobility with respect to temperature is predicted, when the charge in the dislocation core goes through zero. This may turn out to be an accurate means to determine the “neutrality temperature” independent of other methods.