Donor binding energies in multivalley semiconductors

Abstract

The equation for the binding energy of donor impurity states in multi-valley semiconductors, with full inclusion of the Umklapp contributions to intervalley potential matrix elements and of the mass anisotropy is solved variationally for a point-charge impurity pseudopotential. The results are in very good agreement with experiment for Si:P, and Ge:As. The crucial role of Umklapp intervalley scattering contributions to the binding of the ground state is discussed.