Study of weakly alkaline slurry for copper barrier CMP on manufacture platform

This study reports a weakly alkaline slurry (WAS) for copper barrier chemical mechanical planarization (CMP) process in standard 12-inch CMOS manufacture. We do copper barrier CMP process result comparison between current maintream production used slurry (BL) and WAS slurry adopts a unique alkaline macromolecular organic chelating agent with the high activation energy (named FA/O). Based on the same CMP process recipe, WAS shows the better erosion (more than 60% improvement) and dishing (more than 45% improvement) performance than BL. At the same time, WAS keeps the same level performance as BL by inline monitor pad thickness, Rs, and inline defect. All the results show that the WAS has advanced properties and it has potential application for future production line.