Defect dipole engineering enhanced the dielectric performance and reliability of Mn-doped BaTiO3-based multilayer ceramic capacitor

Due to the tendency of base metallization of the inner electrodes in BaTiO3 based multilayer ceramic capacitors (MLCCs), they usually need to be sintered in reducing atmosphere. However, the reducing atmosphere will change the properties of BaTiO3 based dielectric materials, which will affect their properties and applications. Therefore, in this study, BaTi1-xMnxO3 (x = 0.003, 0.006, 0.01) ceramics were prepared by solid phase method and sintered in air and reducing atmosphere. The effects of MnO2 doping and different sintering atmosphere on dielectric properties and reliability of the materials were studied. The results show that the dielectric constant and insulation resistance of the samples decreases with the increase of doping concentration. In addition, the dielectric constant of the samples sintered in air is lower than that in reducing atmosphere, when x = 0.003, the dielectric constant and dielectric loss are 2011, 2205 and 1.5 %, 1.4 %, respectively. This is due to the effect of flippable and non-flippable domain density, which is proportional to the dielectric constant and dependent on the defect dipole. However, the insulation resistivity of samples sintered in air is higher than that in reducing atmosphere, when x = 0.003, it is 3.3 x 10(12) Omega mm and 1.0 x 10(12) Omega mm, respectively. The decrease of insulation resistivity is related to oxygen vacancy and dipole defect. This study provides an important reference for further improving the performance of base metal electrode MLCCs.