CHARACTERIZATION OF EUROPIUM IMPLANTED LINBO3

LiNbO3 single crystals were implanted at room temperature with Eu+ ion s at 70 keV with fluence ranging from 0.5 to 5 X 10(16) ions . cm-2. T he damage in the implanted layer has been investigated by Channeling R utherford Backscattering (RBS-C), and the oxidation states of the cati ons have been determined by x-ray photoelectron spectroscopy (XPS). Fo llowing implantation, a fully amorphized layer of 60 nm is generated, even for the lowest fluence employed. Subsequent annealing in air, in the range 800-1250 K, was applied to restore tentatively the crystalli nity and promote the substitutional incorporation of Eu in the crystal . Only a partial recrystallization of the damaged layer was observed. For as-implanted samples, XPS spectra clearly reveal europium in Eu2and Eu3+ states, and the Nb5+ ions are driven to lower charge states.