Fabrication of Micro-Sized Copper Columns Using Localized Electrochemical Deposition with a 20 μm Diameter Micro Anode

This paper studies the effects of applied potential on the LECD process. which are critical for microelectromechanical systems and semiconductor-related applications. The structures and morphologies of the copper columns can be varied by changing the voltage between the anode and cathode, and high voltage leads to complex structures and morphology. Additionally, the cross section of copper columns was investigated to evaluate the quality of internal structure of columns, and the voids were appeared and the shape of cross section became irregular with the increase of voltage. Finally, the basement of columns was studied for the first time, and three kinds of column basements, i.e., isolated, disordered, and delicate, were identified, and three growth patterns corresponding to the three typical basements types were proposed to describe the basement growth mechanism. (c) 2019 The Electrochemical Society.