Shallow donor surface impurity levels in Si and Ge

Abstract

A previously published variational method for calculating shallow surface impurity levels was extended to include arbitrary orientations of the effective mass ellipsoid relative to the surface. Numerical results appropriate to shallow donors on (100), (110), and (111) surfaces in Si and Ge are given. The results show that the energies are rather strongly dependent on the orientation of the mass ellipsoid. © 1971.