Effects of Li–B–Si–Ca–Mn glass addition on the densification, microstructure, and dielectric properties of (Ca,Sr)(Zr,Ti)O3 ceramics

Abstract

Finding a suitable sintering aid to lower the sintering temperature of the dielectric material is important for making multilayer ceramic capacitors (MLCCs) with copper electrodes. In this study, Li–B–Si–Ca–Mn (LBSCM) glasses were prepared by melt quenching with the addition of an anti-reduction agent as a sintering aid for (Ca0.7Sr0.3)(Zr0.97Ti0.03)O3 dielectric ceramics (CSZT). Based on the defect chemistry and interaction between CSZT and LBSCM glass, the effects of the Li–B–Si glass addition on the sintering, microstructure, and dielectric properties of CSZT were investigated. It was found that the addition of 5 wt% LBSCM glass resulted in a dense microstructure after sintering at a temperature range of 975 °C–1100 °C in 99%N2–1%H2. The capacitance at 1 MHz between 140 and 150 pF, loss of about 0.19%, the breakdown voltage of about 1050 V, insulation resistance around 1011 Ω were obtained for the MLCCs with the size of 0805 using the CSZT added with 5 wt% LBSCM glass as the raw material and copper as the inner electrode sintered at 1000 °C for 1 h and 3 h under a reduction atmosphere of 1% H2/99% N2 mixture gas. This suggests that the CSZT added with 5 wt% LBSCM can be a good candidate as a dielectric material for MLCCs with copper electrodes.