Role of Diethylene Triaminepentaacetic Acid Pentapotassium Salt on Ruthenium CMP in H₂O₂-Based Slurries

As technology is scaled down to 5 nm or even smaller, ruthenium (Ru) will most likely be chosen as the next generation barrier material for copper interconnects in integrated circuits (ICs). Recently, higher removal rate of Ru materials chemical mechanical polishing (CMP) has become a major issue. In this paper, diethylene triaminepentaacetic acid pentapotassium salt (DTPA-5K) was introduced new complexing agent hydrogen peroxide (H 2 O )-based alkaline slurry with goal increasing (RR) during (CMP). The synergy H and DTPA-5K significantly improved RR 412 Å min −1 . Various analytical results, including electrochemical, X-ray photoelectron spectroscopy (XPS), Raman experiments, atomic force microscopy (AFM) confocal microscope data, revealed that can by reducing electrostatic repulsion also forming Ru-DTPA complexes.