BaSnO3 based thermally stable capacitors

Microcrystalline BaSn1−xTixO3–0.5mol%GeO2, x = 0, 0.1, 0.3 (BSTx–0.5Ge) ceramics (0.1–0.75 μm) were prepared by a conventional solid-state reaction method in glazed alumina crucibles. XRD was used to examine the crystalline structure and SEM technique to analyze the microstructure. The density was measured by the Archimedes’s method. The sintered ceramics exhibit at room temperature, a cubic symmetry, with a gradual decrease of unit cell dimensions. GeO2 addition improves crystallization and densification, such as for BS–0.5Ge, at the sintering temperature of 1190 °C, the relative density is 82.7%. Higher titanium doping will lead to denser ceramics: 94.5% for BST3–0.5Ge. For the dielectric constant, a steady value is recorded for all the compositions in a wide range of frequencies (50–500 KHz) and temperatures (150–250, 300–450 K).

► BaSn1−xTixO3–0.5mol%GeO2, x = 0, 0.1, 0.3 ceramics were prepared at 1190 °C.
► GeO2 addition improves crystallization and densification.
► εr′ is constant in a wide frequency range and temperatures (150–250, 300–450 K).