Dielectric properties and microstructures of Ta-doped BaTiO3–(Bi0.5Na0.5)TiO3 ceramics for X9R applications

Ta-doped 0.90BaTiO 3 –0.10(Bi 0.5 Na 0.5 )TiO 3 ceramics were successfully prepared by conventional solid-state reaction method and studied to satisfy super-broad temperature stability. The effects of Ta 2 O 5 doping on the dielectric properties and microstructures were thoroughly investigated. Ta plays an important role in the formation of core–shell structure because of chemical inhomogeneity, which gives rise to the weak temperature dependence of dielectric properties. The samples with the additon of 1.5 mol% Ta 2 O 5 satisfy the X9R specification, exhibiting an optimum dielectric behavior of ε r  ~ 2100, tanδ ~ 1.6% at room temperature, which is a promising candidate material for X9R MLCC applications.