The electronic structure and stability of localised defects in semiconductors. II. Vacancies in silicon, gallium phosphide and zinc selenide

Abstract

For pt.I see ibid., vol.17, p.2575 (1984). The authors present the results of their calculations on the ideal and reconstructed vacancy and divacancy in silicon and the ideal and Jahn-Teller distorted cation and anion vacancies in gallium phosphide and zinc selenide. For the silicon vacancy they find that the charge density profile, the defect potential and the Jahn-Teller parameters are all in agreement with the existing results obtained from the self-consistent Green function methods. They also present a consistent description of the silicon dangling bond. An analysis of the localised structure of the divacancy in silicon is given, and they argue that the electron-lattice coupling at the divacancy should be significantly weaker than that at the single vacancy. The authors provide a comprehensive description of the dangling-bond states of vacancies in GaP and ZnSe and a coherent analysis of their results is presented. They predict a strong and systematic variation in the Jahn-Teller coupling constant across the periodic table, and their results are briefly compared with the existing experimental data.