Production behavior of irradiation defects in α-alumina and sapphire under ion beam irradiation

The production behavior of irradiation defects in α-alumina and sapphire was studied by in situ luminescence measurement technique under ion beam irradiation of H+ and He+. The luminescence intensity of the F+ centers at 330 nm was observed to decrease monotonically with the increasing temperature up to 800 K, while the intensity of the F0 centers at 410 nm to show non-monotonic temperature dependence. In the latter case, the intensity decreased with the temperature up to 600 K, and then increased above this temperature. It was also observed that the luminescence intensity at 410 nm was lower in the He+ irradiation than in the H+ irradiation. These observations were analyzed by considering the production mechanisms and reaction kinetics of the irradiation defects of F-type centers.