Insitu Characterization of Cu CMP with peroxide based slurries containing arginine as complexing agent

摘要

CMP of copper has been performed in alkaline slurry composed of an amino acid (arginine) and peroxide. The role of arginine as a complexing agent in peroxide based slurries during CMP of Cu is characterized by insitu electrochemical experiments. Potentiodynamic polarization and impedance data are analyzed for copper dissolution in hydrogen peroxide and arginine at various speeds of rotation (0, 50, 100 and 150) at different peroxide concentrations. Polarization tests are performed to see the effect of enhancing of dissolution of the copper at different concentrations of peroxide due to complexing action of arginine. And also to study the effect of rotation on anodic dissolution, polarization studies are done at static, rotating with the pad alone, and with the pad and silica particles. Impedance studies are performed to understand the electrochemical interactions during dynamic condition. The behavior of OCP vs time during static and polishing conditions is completely opposite to that of other typical slurries such as glycine + peroxide or citric acid + peroxide. This is probably due to the accumulation of copper ions near the surface during non-polish conditions, which enhance the dissolution rate.