SPECIFIC FEATURES IN THE KINETICS OF THERMALLY STIMULATED LUMINESCENCE OF ALPHA-AL2O3 CRYSTALS CONTAINING DEFECTS

A study of specific features in the kinetics of thermoluminescence (TL ) of defective alpha-Al2O3 crystals is reported. The TL properties are experimentally shown to be related to the presence of oxygen vacancie s of thermochemical or radiation origin. It is established that the di fferences in the TL kinetics in alpha-Al2O3 samples grown under differ ent conditions can be accounted for by the hypothesis that the energy spectra of the trapping levels have different widths. As is demonstrat ed with a titanium impurity, this broadening of the energy spectrum ca n originate from the presence of traces of native impurities in the al pha-Al2O3 lattice. (C) 1997 American Institute of Physics.