Powder synthesis of nano grade cerium oxide via homogenous precipitation and its polishing performance

The nano size cerium oxides (CeO2) were successfully synthesized by homogenous precipitation of ammonium cerium nitrate and urea. The precipitated cubic cerium oxide had primary particle size ∼8 nm with lattice constant about 5.61 Å identified by diffraction pattern of transmission electron microscopy (TEM) analysis. The polishing performance of these powders had been discussed in this present work. The best polishing performance had been found. One weight percent sample C slurry has the removal rate 2258 Å/min for SiO2 film and 220 Å/min for Si3N4 (i.e. the selectivity=10.2). High concentration of urea or the addition of H2O2 in the process seems hurt the polishing performance of these slurries.