Ion beam analysis of interface reactions in magnetite and maghemite thin films

We have investigated interface reactions between expitaxially-grown magnetite (Fe3O4) and maghemite (γ-Fe2O3) films with MgO substrates using Rutherford backscattering (RBS), channeling, and X-ray diffraction (XRD). Annealing these films in 2.0 x 10-6 Torr of O at temperatures up to 970 K enhances Mg outdiffusion into the films and increases the film thickness depending on temperature. The Fe3O4 film thickness reach a limiting value at 870 K anneal while the γ-Fe2O3 film thickness did not maximize after annealing at 970 K. After the annealing at 970 K, both films produced a compound with composition close to magnesioferrite (MgFe2O4). XRD results reveal the formation of MgFe2O4 films after annealing both films at 970 K in O