Using 2 MeV lithium ions backscattering and transmission electron microscopy techniques, some of the xenon atoms introduced by implantation in aluminum metal under the initial oxide layer are shown to be transported by the moving metal-oxide interface during anodic oxidation. For specific anodization conditions (V at, T : 90~ this splitting of the initial xenon distribution is interpreted in terms of bubble formation and growth above a given local concentration threshold. A schematic model for this behavior evolution is proposed. This dose dependance is of practical interest in the determination of transport numbers. Although unambiguously measured they may be subject to significant systematic uncertainties which are discussed.

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