Effects of hydroxyl and trifluoromethyl substituents on the corrosion inhibition of benzotriazole derivatives in copper surface planarization

Abstract

Benzotriazole derivatives are well-known corrosion inhibitors in chemical mechanical planarization (CMP) of integrated circuits, but the effect of their substituents on steric hindrance and hydrophilicity has been almost ignored. In this work, the effect of hydroxyl and trifluoromethyl substituents on the electronic structure, steric hindrance and hydrophilicity of benzotriazole derivatives is studied to evaluate their corrosion inhibition performance in the CMP of copper. The electron-inductive effect of the substituents (–OH and –CF₃) can alter the electron density of the adsorption site, thus affecting the adsorption affinity of corrosion inhibitors. Meanwhile, the steric hindrance and hydrophilicity of –OH might contribute to a looser passivation film, thus facilitating the corrosion processes. Although the steric hindrance of –CF₃ is greater than that of –OH, its hydrophobicity might provide a barrier for film passivation to limit corrosion processes. This work may inspire the development of next-generation corrosion inhibitors for CMP of integrated circuits.