Effect of Inner Electrode on Reliability of (Zn,Mg)TiO 3 -Based Multilayer Ceramic Capacitor

In this study, different proportions of silver-palladium alloy acting as the inner electrode were adopted to a (Zn,Mg)TiO 3 -based multilayer ceramic capacitor (MLCC) sintered at 925 °C for 2 h to evaluate the effect of the inner electrode on reliability. The main results show that the lifetime is inversely proportional to Ag content in the Pd/Ag inner electrode. Ag +1 diffusion into the (Zn,Mg)TiO 3 -based MLCC during cofiring at 925 °C for 2 h and Ag +1 migration at 140 °C against 200 V are both responsible for the short lifetime of the (Zn,Mg)TiO 3 -based MLCC, particularly the latter factor. A (Zn,Mg)TiO 3 -based MLCC with high Ag content in the inner electrode Ag/Pd=99/01 exhibits the shortest lifetime (13 h), and the effect of Ag +1 migration is markedly enhanced when the activation energy of the (Zn,Mg)TiO 3 dielectric is greatly lowered due to the excessive formation of oxygen vacancies and the semiconducting Zn 2 TiO 4 phase when Ag + substitutes for Zn +2 during co-firing.