Kinetics of hydrogen absorption in obliquely deposited MmNi4.5Al0.5 thin films

MmNi4.5Al0.5 thin films of thickness about 1050 Å were obliquely deposited at 3×10−5 torr pressure by thermal evaporation on to a glass substrate at room temperature. The resistance of the films deposited at different angles increases with the absorption of hydrogen and decreases with desorption. The resistance of the samples also increases with the angle of deposition. The change in resistance value is taken as a measure of the amount of hydrogen absorbed in the samples. It is observed that the amount of hydrogen absorbed increases with the deposition angle which is due to an increase in the porosity of thin films.