Effect of electrolyte composition and deposition voltage on the deposition rate of copper microcolumns jet electrodeposition

Abstract

Jet electrodeposition (Jet ECD) is widely recognized for its potential to achieve high deposition rates and adequate field fixation. Currently, the rapid deposition of microscale copper structures remains a significant challenge. In this study, we address this challenge by employing a custom-made microcapillary glass nozzle and optimizing key plating parameters, including H2SO4, CuSO4, KCl concentration, and applied voltage. Through systematic experimentation, we successfully deposited well-formed copper microcolumns with a diameter of 70 μm at a deposition rate of 19.8 μm/s. We discovered that higher concentrations of H2SO4, greater voltage, and the addition of Cl- ions were effective in increasing the deposition speed. Furthermore, a higher concentration of CuSO4 led to improved surface morphology. Additionally, we conducted COMSOL simulations to investigate the influence of voltage and conductivity on the deposition speed. Our research results contribute to the understanding and optimization of rapid fabrication processes for copper microstructures through jet electrodeposition at the microscale.