Synergistic effect of metal cation and 1-dimethylamino-2-propanol on copper corrosion protection in alkaline solution

Abstract

BackgroundCopper (Cu) has versatile applications in microelectronic industry and its corrosion protection in the manufacturing process is an important reliability issue. MethodsIn this study, mixed type corrosion inhibitor is formulated by complexation of metal cation (Ni2+) and tertiary amine (1-dimethylamino-2-propanol), and its synergistic effect on the corrosion protection of Cu in alkaline solution is systematically investigated. Electrochemical, microstructural, and chemical state analyses of the Cu surfaces with and without the inhibitor protection are performed to realize the protection efficacy of the mixed type inhibitor against corrosion. Significant findingsThe results show that the polarization resistance of the Cu surface is increased with the introduction of mixed type inhibitor (Ni2+-1-dimethylamino-2-propanol), achieving a higher inhibition efficiency of 48 % compared to the cation-free inhibitor (1-dimethylamino-2-propanol) of 25 %. The higher inhibition efficiency is attributed to the stronger adsorption capability of mixed type inhibitor on the Cu surface as confirmed by the X-ray photoelectron spectroscopy analysis and quantum chemical calculations.