Preparation of B₂O₃-ZnO-SiO₂ Glass and Sintering Densification of Copper Terminal Electrode Applied in Multilayer Ceramic Capacitors

Abstract

B₂O₃-ZnO-SiO₂(BZS) glass containing CuO with excellent acid resistance, wetting properties, and high-temperature sintering density was prepared by high temperature melting method and then applied in copper terminal electrode for multilayer ceramic capacitors (MLCC) applications. The structure and property characterization of B₂O₃-ZnO-SiO₂ glass, including X-ray diffraction, FTIR, scanning electron microscopy, high-temperature microscopy, and differential scanning calorimetry, indicated that the addition of CuO improved the glass’s acid resistance and glass-forming ability. The wettability and acid resistance of this glass were found to be excellent when CuO content was 1.50 wt%. Compared to BZS glass, the CuO-added glass exhibited excellent wettability to copper powder and corrosion resistance to the plating solution. The sintered copper electrode films prepared using the glass with CuO addition had better densification and lower sintering temperature of 750 °C. Further analysis of the sintering mechanism reveals that the flowability and wettability of the glass significantly impact the sintering densification of the copper terminal electrodes.

Keywords

B₂O₃-ZnO-SiO₂(BZS) / low melting glass / MLCC / densification / copper terminal electrode

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