Metal–non-metal transitions in n-doped many-valley Si and Ge

Abstract

The critical concentration for the metal–non-metal transition in n-doped Si and Ge has been calculated, the electronic system being described by a Hubbard tight-binding model Hamiltonian and the critical point for the transition being taken from the Hubbard III approximation. The disordered arrangement of the impurity atoms, the many-valley nature of the host conduction band minima and the overlap corrections of the tight-binding basis set are taken into account in the calculation. The results show fair agreement when compared to previous work and available experimental data.