Characterization of 57Fe implanted and annealed SnO2 (3% Sb) films by depth selective conversion electron Mossbauer spectroscopy (DCEMS)

SnO2 (3% Sb) films were implanted with 5x1016 57Fe ions/cm² at the substrate temperature of 500°C, and annealed at high temperatures between 400°C and 800°C . These films were characterized by depth selective conversion electron Mössbauer spectroscopy (DCEMS) using a back scattered type of gas proportional counter, and measured by Kerr effect magnetometer. Kerr effect measurements of the SnO2 films showed ferromagnetism at room temperature. The Mossbauer spectra of the as implanted films consisted of paramagnetic doublets of Fe3+ and Fe2+ species and two broad sextets, which showed site A and site B of fine magnetite. The Kerr rotation angles increase step by step with post-annealing up to 700°C. This phenomenon was attributed mainly to ferromagnetic maghemite produced by post-annealing.