Shallow Acceptors in Cadmium Telluride

Abstract

Abstract The photoluminescence spectroscopy of undoped CdTe crystals provides information on two acceptors which are the main contaminants of as‐grown crystals. These acceptors called y and z have their respective ionization energies at 147 and 108 meV. A complete series of two hole replicas is observed for y and only one for z. These acceptors are believed to be due to Cu and Ag impurities. Backdoping experiments with Li and Na give rise to new transitions. From the conduction band–acceptor level transitions, the ionization energies are respectively obtained to 57.8 and 58.8 meV. In the case of Li, some extra‐lines are tentatively identified as phonon interacting two‐hole transitions.