Effects of manganese oxide–mixed abrasive slurry on the tetraethyl orthosilicate oxide chemical mechanical polishing for planarization of interlayer dielectric film in the multilevel interconnection

In this article, the authors have studied the chemical mechanical polishing (CMP) characteristics of mixed abrasive slurry (MAS) retreated by adding of manganese oxide $(MnO2)$ abrasives within 1:10 diluted silica slurry. The slurry designed for optimal performance should produce reasonable removal rates, acceptable polishing selectivity with respect to the underlying layer, low surface defects after polishing, and good slurry stability. The modified abrasives in MAS are evaluated with respect to their particle size distribution, surface morphology, and CMP performances such as removal rate and nonuniformity. As an experimental result, the authors obtained the comparable slurry characteristics compared to original silica slurry in the viewpoint of high removal rate and low nonuniformity.