Potassium ions were implanted into hydrothermally grown ZnO to a dose of 1015/cm2, followed by isochronal annealing in a tube furnace (30min) and by rapid thermal annealing (30s) on two separate samples. For annealing temperatures below 700C, only a minor redistribution of Li was observed behind the projected range of the K+ ions. At temperatures between 700 and 750C, however, both annealing treatments showed a wide region behind the implantation peak which was depleted of Li, and this depletion was used as a tracer to monitor diffusion of intrinsic defects like the Zn interstitial. The results were interpreted as being due to Zn interstitials being released from the implanted region in a burst at temperatures above ∼700C, followed by rapid migration, replacement of Li on Zn site through the kick-out mechanism, and migration of Li away from the active region.

Anomalous Diffusion of Intrinsic Defects in K+ Implanted ZnO using Li as Tracer. Vines, L., Neuvonen, P.T., Kuznetsov, A.Y., Wong-Leung, J., Jagadish, C., Svensson, B.G.: Materials Research Society Symposium Proceedings, 2011, 1394, 75-80