2007 Volume 48 Issue 4 Pages 832-835
Purification of hydrogen using a hydrogen storage alloy film has various advantages such as low operation energy and low costs of the equipment. However, because of the surface roughness of a substrate, the surface of the sputtered film was not smooth and had some pinholes. It was considered that use of a bias sputtering method might solve these problems. Hence, in this study, the influence of the bias power on the composition, microstructure and crystal structure of the LaNi5 sputtered film were investigated. When the film was deposited with a direct current sputter power WS=50 W and a radio frequency bias power WB=20 W, the diffraction peak of LaNi5 was not observed on the film. With WS=200 W and WB=20 W, the film had crystal structures. However, when the WB was increased more than 40 W with WS=200 W, the film became the amorphous structure. It is considered that, to make the amorphous structure and the dense film with higher WS, the WB has to be increased.