Influence of Rare‐Earth Dopants on Barium Titanate Ceramics Microstructure and Corresponding Electrical Properties

Abstract

In this article, ytterbium and erbium oxides are used as doping materials for barium titanate (BaTiO 3 ) materials. The amphoteric behavior of these rare‐earth ions leads to the increase of dielectric permittivity and decrease of dielectric losses. BaTiO 3 ceramics doped with 0.01–0.5 wt% of Yb 2 O 3 and Er 2 O 3 were prepared by conventional solid‐state procedure and sintered at 1320°C for 4 h. In BaTiO 3 doped with a low content of rare‐earth ions (0.01 wt%) the grain size ranged between 10 and 25 μm. With the higher dopant concentration of 0.5 wt%, the abnormal grain growth is inhibited and the grain size ranged between 2 and 10 μm. The measurements of capacitance and dielectric losses as a function of frequency and temperature have been carried out in order to correlate the microstructure and dielectric properties of doped BaTiO 3 ceramics. The temperature dependence of the dielectric constant as a function of dopant amount has been investigated.