Study of Cu-Inhibitor State for Post-Chemical Mechanical Polishing Cleaning

In order to reduce corrosion on the Cu surface in post-chemical mechanical polishing (CMP) cleaning, controlling the state of inhibitor layers is indispensable. In this study, to investigate the behavior of inhibitor layers in the cleaning process, Cu–benzotriazole (BTA) layers on CuO X were analyzed by electrochemical measurements and surface analysis. Electrochemical measurements revealed that Cu(I)–BTA can prevent corrosion more efficiently than Cu(II)–BTA, and surface analysis revealed that the Cu(I)–BTA layer is thin, whereas the Cu(II)–BTA layer is bulky. The Cu(I)–BTA layer is effective in preventing corrosion of the Cu surface.