GOLD WETTING EFFECTS ON SAPPHIRE IRRADIATED WITH GEV URANIUM IONS

Single crystals of alpha-Al2O3 were irradiated with U-238 ions using t wo different energies: 3.4 MeV/u and 1.7 MeV/u. The irradiations were performed at a temperature of approximate to 80 K, with fluences rangi ng from 1.2 X 10(12) to 2.5 x 10(12) ions cm(-2). After irradiation, t hin gold films were deposited on the sapphire surfaces by using a sput tering method. Subsequent annealing in air at a temperature of 723 and 923 K were applied to investigate the influence of the pre-damage on the adhesion of the gold layer on the sapphire surface. Rutherford bac kscattering analysis and scanning electron microscopy performed in bot h virgin and irradiated areas, show that the pre-irradiation damage in hibits the gold film of breaking up into islands after annealing. A we tting effect, which could depend on the damage morphology, is clearly observed.