Advances in chemical mechanical polishing of Cu interconnects

摘要

Recent advances in chemical mechanical polishing (CMP) of Cu interconnects are reported in this paper. It will be shown that using an optimized consumable set and a 2-step Cu CMP approach (pad, slurry, and post Cu CMP cleaning solution), consistent Cu removal rate and uniformity, excellent pattern wafer performance (retention of Ta in dense pattern density area after 1~(st) step Cu polishing, and low Cu dishing and oxide erosion), corrosion-free Cu lines, low defectivity and Cu contamination level can be achieved.