The effect of Y2O3 addition on He desorption behavior and He bubble evolution in He-charged W-Y2O3 film

Abstract He-charged W films and He-charged W-Y2O3 films have been fabricated by RF magnetron sputtering in a mixed atmosphere of He and Ar. The growth mechanism of He bubbles/blisters in He-charged W/W-Y2O3 films was investigated by the isochronal annealing at different temperatures (773 K, 973 K, and 1273 K, respectively). Compared with the case of He-charged W film without Y2O3 addition, Y2O3 addition restrain obviously He blistering in He-charged W-Y2O3 film. It seems that the addition of Y2O3 can inhibit in some extent the growth of He bubbles in W-Y2O3 film according to transmission electron microscopy observations. Thermal desorption spectroscopy analysis indicates that there are five He desorption peaks within the range of 1273 K in both the as-deposited He-charged W/W-Y2O3 films, and it exists as well as an inhibiting effect of Y2O3 addition on the entrapping or de-trapping of He atoms in W-Y2O3 film.