The interaction of deep traps in anion-defective alpha-Al2O3

摘要

This paper deals with the examination of thermoluminescence (TL) optical spectra (200-800 nm) for deep traps (DT) observed near 730 K (DT1) and 785 K (DT2) at beta = 2 K/s in dosimetric alpha -Al2O3 crystals. The DT1 spectrum consisted of two luminescence bands near 3.56 and 2.42 eV. The DT2 spectrum had one band near 2.95 eV. The 3.56 eV emission band was assigned to the F+-center luminescence and the 2.95 eV band to the F-center luminescence. The excitation spectra of the 2.42 eV emission band measured at RT had one peak at 4.11 eV. The intensity correlated with filling of deep traps. It was supposed that anion-defective corundum contained complex F-type centers. The state of those centers changed upon exposure to UV irradiation at a high temperature. (C) 2001 Elsevier Science Ltd. All rights reserved. [References: 9]