Study on Ceria Slurry for Chemical Mechanical Polishing of 4H-SiC

Chemical mechanical polishing technology is an important means for achieving global flatness in integrated circuit manufacturing, and the abrasive, oxidant and additive in the polishing slurry are vital factors that affect the polishing results. This paper investigates the effect of incorporating cationic surfactant based on ceria (CeO2) and potassium permanganate (KMnO4) for the material removal rate and the surface quality of silicon carbide (SiC). The polishing slurry is formulated with 2 wt% ceria, 0.025 mol/L KMnO4, and cationic surfactant at pH 4.0. The maximum material removal rate (MRRmax) of SiC is 777 nm/h, and the surface roughness (Sq) is 0.06 nm.