Bombardment-induced structural changes in non-metallic solids are known to occur in three forms: amorphization, crystallization or stoichiometry changes. A versatile technique to study the formation and annealing of structural changes is to produce the damage with rare gas ions and to use the release of these rare gas ions as a probe for damage annealing.1Other techniques include electron diffraction,1measurement of range profiles,2of solubility3or electrical conductivity.4