Neutral Impurity Scattering in Semiconductors

Abstract

The scattering of free charge carriers by neutral impurities in semiconductors has been calculated using the partial wave technique by considering the source of scattering to be an attractive potential caused by a negative-energy state associated with the neutral impurity. This calculation has been compared with that due to Erginsoy and with a calculation in Born approximation where the neutral impurity is represented by a hydrogen atom in the dielectric medium of the semiconductor. The present treatment gives a mobility that differs from the Erginsoy treatment by only a few percent but predicts a slight temperature dependence. The calculation in Born approximation gives a result similar to that obtained for ionized impurity scattering calculated to the same approximation. The nature of the energy state giving rise to the scattering in this treatment and the possibility of distinguishing experimentally between the different calculations is discussed.