Post CU CMP polishing for reduced defects

摘要

Cu metallization is treated to reduce defects and effect passivation, and to reduce leakage between lines, by removing surface defects subsequent to CMP and barrier layer removal. Embodiments include the sequential steps of: CMP and barrier layer removal; buffing with a solution comprising citric acid, ammonium hydroxide and deionized water to remove copper oxide; rinsing with deionized water or an inhibitor solution, e.g., benzotriazole or 5-methyl triazole in deionized water; buffing with an abrasive slurry; and rinsing with deionized water or an inhibitor solution.