Structure and Microstructure of Y-doped Strontium Titanate Ceramics

High dielectric constant important for functional electronic applications have been reported in the Sr_1-1.5xY_xTiO₃ ceramic system with a maximum value for x = 0.01 coincident with the maximum grain size. This observation points to a possible correlation between the dielectric response and the microstructure of these ceramics. A solid solubility limit around x = 0.04 was reported recently by Fu et al., although the second phase was observed by X-ray diffraction only for x = 0.07. Therefore, the structure, microstructure and local composition of Sr_1-1.5xY_xTiO₃ ceramics (x = 0 − 0.05) prepared by conventional mixed oxide method is investigated in this work by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy facilities.