Development of Copper CMP Slurry

Chemical mechanical planarization (CMP) is a critical technology for the copper damascene process. With the development of more advanced technology nodes, New challenges have emerged for the conventional CMP processes--the need for using lower down force while maintaining removal rate to avoid low-k/ultra-low k dielectric film damage and wide over polishing window. Also, surface defects especially corrosion related defects become more stringent as copper line becomes narrower and narrower. In this paper, we share our current efforts and associated results to develop the novel copper slurry for such CMP process. The slurries with different organic additives were evaluated for removal rate, dishing rate, electrochemical analysis and anti-corrosion capability. Based on these results, a novel copper slurry has been developed and it shows the excellent CMP performance.