Irreversible and reversible annealing of paramagnetic oxygen vacancies (E′1 centers) in oxygen-implanted amorphous SiO2

Abstract

The creation/annihilation dynamics of E1 defects induced in thermal SiO2 by implantation of N+ and O+ ions has been studied using electron paramagnetic resonance. A new effect of the irreversible self-annealing of E′1 defects has been observed for RT O+ implants. This effect correlates with the average concentration of implanted oxygen atoms within the saturated damage volume. Low-temperature (100<T<300 °C) E1 defect annealing behavior appears to correspond to reversible oxygen vacancy charge transformation E′1⇄B2 via a hole release/trapping process. Irreversible thermal annealing of E1 centers is observed at temperatures T>500 °C. However, the isochronal annealing behavior does not correspond to Waite’s model based on the molecular oxygen diffusion mechanism.