REVERSIBLE CHANGES OF PROPERTIES OF PURE CDTE BY ANNEALING AND AGING

We report the first observation in CdTe of a reversible photoluminesce nce spectral transformation between the Z-luminescence system and the 'self-activation' band by high-temperature treatments and aging at roo m temperature. We propose that some residual impurity is responsible f or both Z-recombination (isolated impurity) and the self-activation ba nd at approximately 1.45 eV (complex with a shallow donor). There is r eason to believe that a key to understanding the compensation mechanis m is the formation of impurity complexes consisting of the shallow imp urity (donor or acceptor) and the Z centre.