Study of iron implanted MgO crystals by low-energy electron induced X-ray spectroscopy

Magnesium oxide crystals implanted with Fe⁺ ions have been studied by means of Low-Energy-Electron-Induced X-ray Spectroscopy. All the implantations were carried out with 100 or 150 keV ion energy, at doses in the range from 10¹⁵ to 10¹⁷ ions cm^?2. The structure of the Fe L_II, L_III X-ray emission bands provides information about the iron chemical state. Fe L_II/L_III band intensity ratio measurements have been performed with a 3 keV electron excitation in order to investigate the whole implanted layer. In addition, by using a filtered Fourier transform technique on observed spectra, some modifications in the oxygen K emission band can be observed in implanted MgO crystals after thermal annealings in air. The oxygen spectrum fine structure suggests that the MgO matrix, partially destroyed by iron implantation, is restored after high temperature treatments. All the implantation, is restored after high temperature treatments. All the results are discussed on the basis of previous Mössbauer Spectroscopy studies and ion channeling investigations.