Enhancement of Ti diffusion in MgO(100) pre-bombarded with 7keV Ar+ was observed. Diffusion was induced by annealing to 1000C following the pre-bombardment and Ti evaporation. Such a sample geometry and experimental procedure alleviates the continuous provision of freely mobile defects introduced by ion irradiation during annealing for diffusion, making diffusion proceed in a non steady-state condition. Diffusion penetration profiles were obtained by using secondary ion mass spectrometry depth profiling techniques. A model that included a depth-dependent diffusion coefficient was proposed, which successfully explains the observed non steady-state radiation enhanced diffusion. The diffusion coefficients were of the order of 10–20m2/s and were enhanced due to the defect structure inflected by the Ar+ pre-bombardment.

Ti Diffusion in Ion Prebombarded MgO(100) - a Model for Quantitative Analysis. M.Lu, C.Lupu, V.J.Styve, S.M.Lee, J.W.Rabalais: Journal of Vacuum Science & Technology A, 2002, 20[1], 174-9