Effect of Ionizing Radiation on Displacement Damage in Ion-Bmcbarded Single Crystal α-A12O3 and α-SiO2

Volume changes in ion-bombarded single crystals of sapphire and α-quartz have been investigated as functions of ion mass and initial energy and of the energy partitioning into atomic and ionization processes. In addition, channeled proton-induced X-ray measurements were made of displacement damage after ion bombardment. Results indicate an ionization stimulated annealing effect of the radiation damage in sapphire which prevents this material from becoming amorphous even at high ion fluences. In contrast, α-quartz shows no such annealing effect and loses its crystallinity completely at high ion fluences.