Relation between the common anion rule and the defect model of Schottky barrier formation

We present calculations of the energy levels of anion vacancies near the (110) surface of GaInAs, GaInP and GaAlAs. The results suggest that the defect model of Schottky barrier formation with anion vacancy-like states being responsible for Fermi level pinning is consistent with the common anion rule as observed in GaInAs and GaInP and also with the exception to the rule presented by GaAlAs.