EVIDENCE FOR ORDERED METAL HYDRIDE PRODUCTION BY LOW-TEMPERATURE ION-IMPLANTATION

Order and disorder induced by low temperature hydrogen implantation in thin metallic films of palladium and nickel were studied by residual resistivity measurements versus implanted dose, up to H concentrations approximately equals 120-130%. Evidence for proton ordering in octahedral interstitial sites was shown, even if the targets are previously disordered. In contrast to the low hydrogen concentration range, where Matthiessen's rule seems to be valid, the resistive contributions of hydrogen and implantation-induced disorder were not found to add independently at high implanted proton doses.