Stress measurements were performed in situ on alkali-borosilicate glass samples, during and after 2MeV Xe ion bombardment at temperatures of between 95 and 580K. After stopping the bombardment, stress changes were observed that were related to the annealing of beam-generated defects. The activation energy spectra for defect annealing were obtained from data for each irradiation temperature. Defects were observed for energies ranging from 0.26 to 1.85eV. At each temperature, the spectrum increased monotonically with the activation energy. At each energy, the defect density per unit energy was smaller at higher temperatures. This behavior could be explained by using a binary collision model. The data were contrasted with those for 4MeV Xe ion bombarded thermally-grown SiO2 films, which could be explained by using a thermal spike model. Measurements of a radiation-induced viscosity supported this idea.

Activation Energy Spectra for Annealing of Ion Irradiation Induced Defects in Silica Glasses. T.Van Dillen, M.L.Brongersma, E.Snoeks, A.Polman: Nuclear Instruments and Methods in Physics Research B, 1999, 148[1-4], 221-6