In-Situ Stress Measurements During Electrodeposition of Chromium Films

Chromium is widely used in many decorative and engineering applications. Recently, solution based on Cr3+ as environment-friendly bath has attracted interests for chromium deposition. However, Chromium thin film deposited from Cr+3 forms cracks, which causes reliability problems. Earlier incorporation of chromium hydride during the growth and its decomposition after the deposition have been realized as the causes of the cracks. Thus, pulse current deposition approach with periodic “on” and “off” time proposed as a solution. In our study, we focus on the stress evolution of chromium film deposited with various parameters to find pulse current function that effectively removes hydride from the film. Our results showed hydride removal occurs at “off” time which is 27 times longer than “on” time, which is not practical in industry. We have found effective hydride removal happens in a cycle with Xs “on” time and 7Xs “off” time where X is more than 1s.