The influence of tungsten substrates on hydrogen absorption by iodide titanium films

Iodide titanium films have been grown on tungsten substrates by means of a TiI4 flow system. It was found that tungsten diffusion takes place during the titanium film deposition. Tungsten concentrations as high as 14 at.% have been recorded at 1350 degrees C deposition temperature. On cooling the films to room temperature, titanium remains in the beta phase to an extent that depends on the film deposition time. The films were hydrogenated at 500 degrees C and a large hysteresis effect was observed in the P-X diagram. This hysteresis effect is explained by considering the influence of the tungsten diffusion into the films.