An investigation was made of the effects of an electric field upon the formation of interstitial-type dislocation loops in α-Al2O3 which had been bombarded with 100keV He+ ions to a damage level of 0.5dpa at 760K. An electric field of 100kV/m depressed the density of dislocation loops and enhanced their growth, as compared with microstructures which had been bombarded with no electric field. In addition, a higher fraction of interstitials escaped to surface sinks, in a wedge-shaped thin-foil specimen, when bombarded in the presence of an electric field. The kinetic behaviour of interstitials was explained in terms of diffusion processes which were driven by the electric field and the concentration gradient. This was the first transmission electron microscopic demonstration of the effects of an electric field upon the aggregation of bombardment-induced defects in α-Al2O3.

Effects of the Electric Field on the Aggregation of Point Defects in Ion-Irradiated α-Al2O3: K.Yasuda, T.Higuchi, K.Shiiyama, C.Kinoshita, K.Tanaka, M.Kutsuwada: Philosophical Magazine Letters, 2003, 83[1], 21-8