Newly developed electro-chemical polishing process of copper as replacement of CMP suitable for damascene copper inlaid in fragile low-k dielectrics

A new principle for the copper removal process, Electro-Chemical-Polishing (ECP), to replace CMP is demonstrated. ECP which leverages electrochemical dissolution of copper has removal rates determined by the imposed current, higher than 8000 A/min, while "planarization" is made by wiping out copper complexes at a wiping pressure ten times lower than that for CMP to form erosion- and scratch-free damascene copper interconnects. ECP is a promising replacement for CMP suitable for copper inlaid in fragile low-k materials.