Dielectric Properties of Erbium Doped Barium Titanate

The effect of Er ion incorporation into the stoichoimetric BaTiO3 on the dielectric properties and microstructural developement was studied. In the case of Er addition to the stoichoimetric BaTiO3 up to 2.0 mol%, there was no change in the Curie temperature. The presence of excess Er greater than 3.0 mol% led to an oxygen-deficient nonstoichiometry, resulting in a shift in the Curie point toward lower temperatures concurrent with the formation of the second phase, identified as Er2Ti2O7. The acceptor-doped behavior with the oxygen-deficient nonstoichiometry and the formation of the second phase are discussed in terms of the solubility and mode of incorporation of Er into BaTiO3.