Crystallographic Polarity in the II-VI Compounds

Abstract

Crystallographic polarity associated with the zinc-blende and the wurtzite structures has been studied in the following II-VI sulfides, selenides and tellurides; ZnS, ZnTe, CdS, CdSe, CdTe, HgSe, and HgTe. The CdS and CdSe have the wurtzite structure and the others the zinc-blende structure. Consistent with theoretical calculations, the geometric structure factor for x-ray scattering was found different in opposite directions along the polar axis. Consequently, the two types of surfaces perpendicular to the polar axis were identified. The etching behavior of these surfaces was correlated with the x-ray results so that simple etching tests were developed for the identification of the {111} (zinc blende) or the {00.1} (wurtzite) surfaces.