Microstructure and Electrical Properties of Al₂O₃-Doped Ba_0.9Ca_0.1Ti_0.8Zr_0.2O₃ Based Dielectric Ceramics

Abstract

Al 2 O 3 -doped Ba 0.9 Ca 0.1 Ti 0.8 Zr 0.2 O 3 (short for BCTZ) based dielectric ceramics were fabricated by sintering samples at 1300°C for 2h with conventional ceramic processing method. The microstructure and electrical properties of the as-prepared samples were investigated. X-ray diffraction analysis showed that after the addition of Al 2 O 3 with the amount designed in this study, no new phase was examined in the detection limit. Through scanning electron microscopy it was found that the doping of Al 2 O 3 can help the growth of BCTZ grains, and the relative permittivities of the samples. The result of electrical properties indicated that the resistance and the break voltage of the samples could be improved to some extent with appropriate doping amount of Al 2 O 3 resulting in the highest dielectric constant ~17000, low dielectric loss <10%, and highest break voltage 8.4 kV/mm, respectively.