(001)-Surface-induced bulk and surface states in wide band gap sincblende II-VI semiconductors

Abstract

In a previous paper [\prb {\bf 50}, 1980 (1994)] we gave account of the nondispersive band first found experimentally at --4.4 eV for CdTe(001) by Niles and Höchst. We have characterized this band as a surface--induced bulk state. In a second paper we showed that a similar state does exist in II--VI and III--V zincblende semiconductor compounds. In this paper we show that there are more such states within the valence band energy interval. We use tight-binding hamiltonians and the surface Green's function matching method to calculate the surface and surface--induced bulk states in the wide band gap zincblende semiconductors CdTe, CdSe, ZnTe and ZnSe. We find a distinctive surface state for the cation and two for the anion termination of the (001)--surface and three (001)--surface--induced bulk states with energies that correspond to the value of the heavy hole, light hole and spin--orbit bands at $X$.