Characterization of copper pastes for end termination application of base metal electrode MLCCs

The steep rise in the cost of palladium metal in the last decade has necessitated significant research and development efforts for using the base metal nickel electrodes in the manufacture of multilayer ceramic capacitors (MLCCs). Copper termination paste is hence a natural choice for end termination application of MLCCs using nickel electrodes, manufactured employing the base metal electrode (BME) process. The inert nitrogen atmosphere processing of the BME MLCCs has posed many challenges in the selection of organics (vehicles, binders, and additives), copper powders, and glasses for copper termination paste development. The effect of various organics and glasses on the drying as well as fired properties of different copper termination pastes is discussed. The effect of drying temperature and drying time on the fired properties of the copper termination, and the selection criteria for right composition of glass for copper termination paste are discussed. The properties of low and high firing temperature copper termination pastes are also presented.