Preparation of Monodisperse Ti-Doped Colloidal SiO2 Composite Abrasives and Their Chemical Mechanical Polishing Performances on Sapphire Substrates

Abstract

Chemical mechanical polishing (CMP) process has become a widely accepted global planarization technology. Abrasive is one of the key elements in CMP. In the present paper, a series of novel Ti-doped colloidal SiO2 composite abrasives were prepared by seed-induced growth method. The CMP performances of the Ti-doped colloidal SiO2 composite abrasives on the (0001) plane sapphire substrates were investigated. The analyses on the surfaces of polished sapphire substrates indicate slurries containing the Ti-doped colloidal SiO2 composite abrasives achieve lower surface roughness and higher material removal rate than that of pure colloidal SiO2 abrasive. X-ray photoelectron spectroscopy analysis shows that solid-state chemical reactions between Ti-doped colloidal SiO2 abrasive and sapphire surface occur during CMP process, which can promote the chemical effect in CMP and improve the material removal rate.