Internal Stress in Nickel Thin Films Electrodeposited by a Rectangular Current Pulse Technique

A scaling behavior of the internal stress in a nickel thin film electrodeposited by a rectangular current pulse technique was investigated using a bent strip measurement. The internal stress that appears as a tensile stress is found to obey a scaling law represented by power laws of the film thickness and the Faradaic current pulse amplitude in one period. An increase in the film thickness combined with the fluctuation of the surface roughness in a statistical surface growth model decreases the internal stress. A decrease in the Faradaic current pulse amplitude that indicates a number of nickel ions arriving at the electrode in one period lessens the internal stress owing to an increase in the mean grain size. The scaling behavior of the internal stress suggests that the internal stress links the surface topography.