Effect of CeO₂ Nanoparticles on Interface of Cu/Al₂O₃ Ceramic Clad Composites

Cu/Al₂O₃ ceramic clad composites are widely used in electronic packaging and electrical contacts. However, the conductivity and strength of the interfacial layer are not fit for the demands. So CeO₂ nanoparticles 24.3 nm in size, coated on Al₂O₃ ceramic, promote a novel CeO₂-Cu₂O-Cu system to improve the interfacial bonded strength. Results show that the atom content of O is increased to approximately 30% with the addition of CeO₂ nanoparticles compared with the atom content without CeO₂ in the interfacial layer of Cu/Al₂O₃ ceramic clad composites. CeO₂ nanoparticles coated on the surface of Al₂O₃ ceramics can easily diffuse into the metallic Cu layer. CeO₂ nanoparticles can accelerate to form the eutectic liquid of Cu₂O-Cu as they have strong functions of storing and releasing O at an Ar pressure of 0.12 MPa. The addition of CeO₂ nanoparticles is beneficial for promoting the bonded strength of the Cu/Al₂O₃ ceramic clad composites. The bonded strength of the interface coated with nanoparticles of CeO₂ is increased to 20.8% compared with that without CeO₂; moreover, the electric conductivity on the side of metallic Cu is 95% IACS. The study is of great significance for improving properties of Cu/Al₂O₃ ceramic clad composites.