Single crystals with y-cut orientations were irradiated with 5.17MeV 155Gd ions to fluences ranging from 1.5 x 1011 to 6.0 x 1011/cm2. After irradiation, the samples were implanted with 70keV Eu ions to a fluence of 5 x 1016/cm2. The irradiation and implantation were carried out at room temperature. Heat treatment in air, at temperatures ranging from 300 to 1100C, was used to investigate the effect of the pre-irradiation damage upon the thermal evolution of Eu-implanted crystals. Transmission electron micrographs revealed amorphous tracks which were formed by the high-energy irradiation. Rutherford back-scattering spectrometric results showed that the amorphous tracks enhanced Eu diffusion. The results could be described by:

D (cm2/s) = 4.2 x 10-15 exp[-0.42(eV)/kT]

S.M.M.Ramos, R.Brenier, B.Canut, G.Fuchs, P.Thevenard, M.Treilleux, A.Meftah, M.Toulemonde: Journal of Applied Physics, 1995, 77[7], 2952-6