Point defects and the pre-dose effect in quartz

The thermal annealing properties of (H3O4)0 centres in single crystal SiO2 were studied by means of electron spin resonance (ESR). The data indicate that these centres take part in the TL process at 1100C in this material. The mechanism suggested for this TL signal is the thermal release of electrons from (GeO4)- centres and their recombination with holes trapped at (Al04)0 and (H3O4)0 centres. We have also monitored the radiation-induced infra-red absorption bands in order to examine the thermal stability of AlOH centres. Correlations between the AlOH annealing curves and the pre-dose thermal activation curves indicate that hydrogen impurities are mobile in the quartz lattice during the pre-dose activation sequence. (author)