Doppler broadening measurements of the 511keV positron annihilation line-shape were carried out in order to study the nature of vacancy-type defects. The results of annealing at temperatures ranging from 300 to 450K indicated an unusual reversible variation with temperature which was attributed to the role of impurities or native defects in the sample. Further annealing, at temperatures of up to 570K, produced an increase in the vacancy concentration. This was due to the formation of a new type of defect. Extensive annealing at this temperature gradually changed the sample to a coral-like structure of CdTe, as Hg and Te were lost from the sample.

C.Smith, P.C.Rice-Evans, N.Shaw, D.L.Smith: Journal of Physics - Condensed Matter, 1992, 4[26], 5825-34