Mechanical hardening of electrochemically deposited aluminum from chloroaluminate ionic liquid

Abstract

In establishing electrochemically deposited Al as a structural microdevice, its surface uniformity and mechanical properties such as the hardness are of great importance. In this study, an improvement of surface uniformity and mechanical hardening of the film by factors of about 100 and 4, respectively, are reported. Both were associated to the grain size effect, which is attributed to the inclusion of 2-chloronicotinyl chloride additive acting as a grain growth inhibitor in the electrochemical bath. Other important properties, such as the elastic modulus, residual stress and electrical resistivity of the deposit are also studied. This study holds a great potential to pave the way for the utilization of the electrochemically deposited Al in microsystems and related technologies.