Contribution of SIMS to the study of the atomic transport in Cr2O3 and Al2O3 oxides

Amongst various techniques which can be used for determining diffusion coef ficients, in refractory materials such as oxides, it is shown that the SIMS technique offers particular advantages. Especially, SIMS is one of the rar e techniques for determining diffusion coefficients in oxide thin films. Consequently, selfdiffusion results obtained during the last ten years in m assive Cr2O(3) and Al2O3, using isotopic oxygen exchange or thin film metho d and SIMS analysis of the penetration profiles, are presented and used for the calculation of the oxidation kinetic constants. It appears that there is no agreement between calculated and experimental oxidation constants. Inversely, if diffusion is performed in thin Cr2O3 or Al2O3 layers, using S IMS for the establishment of the penetration profiles, and with some precau tions in the diffusion analysis, then, there is agreement between calculate d and experimental oxidation constants.