Dielectric properties of A- and B-site doped BaTiO3: Effect of La and Ga

Extremely small amounts of La and Ga doping on the A- and B-site of BaTiO3, respectively, resulting in a solid solution of the type Ba1−3xLa2xTi1−3yGa4yO3 have been investigated. The present work dwells on the influence of the individual dopants, namely La and Ga, on the dielectric properties of BaTiO3.The compositions have been prepared by solid-state reaction. X-ray diffraction (XRD) reveals the presence of tetragonal (P4/mmm) phase. The XRD data has been analyzed using FULLPROF, a Rietveld refinement package. The microstructure have been studied by orientation imaging microscopy (OIM). The compositions have been characterized by dielectric spectroscopy between room temperature and 250 °C. Further, the nature of phase transition has been studied using high temperature XRD. The resulting compounds exhibit high dielectric constant, enhanced diffuseness and low temperature coefficient of capacitance.