Synthesis of CeO2 Nanoparticles Derived by Urea Condensation for Chemical Mechanical Polishing

Abstract

The synthesis of CeO₂ nanoparticles for CeO₂ based slurry gains continuous emphasis on improving its performance in the chemical mechanical polishing of dielectric materials. Urea was selected to dominate the growth and morphology during the calcination process. Thermogravimetry experiments were used to analyze the the decomposition behavior. Particle morphology and size were analyzed. Crystalline phase information and surface valence were used to compare the differences in surface physical and chemical properties of ceria by different synthesis process. The CeO₂ nanoparticles synthesized with urea were dispersed in water as slurry. The particle sizes of CeO₂ were measured by dynamic light scattering. The Zeta potential of CeO₂ dispersion were measured to show dispersing performance. The CeO₂ nanoparticles synthesized with urea condensation show good monodisperse properties. The material removal rate of silicon oxide and surface quality after chemical mechanical polishing were selected to evaluate the chemical mechanical polishing performance. The CeO₂ nanoparticles synthesized with urea condensation not only yielded better surface quality results than the commercial slurry but also showed a 153% (pH = 4) and 100% (pH = 10) increase in the material removal rate of silicon oxide compared to commercial.