Effects of doping sites on electrical properties of yttrium doped BaTiO₃

Ba_1-xY_xTiO₃ (BYT), BaTi_1-yY_yO_3-y/2 (BTY) and Ba_1-zY_zTi_1-zY_zO₃ (BYTY) are prepared by using a solid state reaction method. Their lattice parameters and solubility are determined. And the correlations between doping sites, concentrations and electrical properties are studied. Doping Y³⁺ at A-site, which is associated with the electron compensation, leads to high conductivity in BYT, accompanied by giant permittivity and large dielectric loss. However, BTY is relative insulating since its doping mechanism is dominated by the charge compensation of oxide ion. Although BYTY is self-compensated, it behaves more semiconductive, which is probably due to the oxygen loss during the sintering at high temperature.