Very dilute (about 1012/cm3) In donors in CdTe powders, and in CdTe monocrystals, were investigated by means of 111In perturbed angular correlation spectroscopy. Most of the In atoms were located in un-complexed sites, but could form weakly-bound complexes with native defects in highly defective material. The only complex which was observed in CdTe was an In-Cd vacancy pair. The CdTe in which these pairs occurred appeared to be n-type, most of the Cd vacancies were free and doubly-charged, and the binding energy with In was equal to 0.15eV. In the case of ZnSe, the In could pair with a Zn vacancy or with another (unidentified) defect. These complexes formed in ZnSe which contained large concentrations of both free Zn vacancies, and complexes of Zn vacancies with other defects. In the case of CdTe, the pair formation equilibration time-constant was equal to 48h at 15C; thus implying that Cd vacancies were mobile at room temperature.

J.W.Griffith, R.Lundquist, R.Platzer, J.A.Gardner, G.Karczewski, J.K.Furdyna: Materials Science Forum, 1994, 143-147, 405-10