Structural and dielectric tunable properties of BaSrTiSiO microwave ceramics.

The structure-property relationships in BaSrTiSiO with y=0.00, 0.01, 0.02, 0.05, 0.10 and 0.20 ceramics have been studied by using X-ray diffraction, electron microscopy and dielectric spectroscopy. An increase of Si concentration is not favorable for the stability of the perovskite structure, which results in the formation of BaTiSiO5 secondary phase. The dielectric peaks of samples are suppressed, broadened and shifted to low temperature with increasing Si concentration. Permittivity and Q value are reduced gradually with increasing Si concentration, due to growing of second BaTiSiO phase. The tunability ( T) still remains ∼18.0% under 60 kV/cm biasing for the samples with y⩽0.10. The best combination of microwave dielectric properties are obtained for the composition of y=0.10: ɛ=531, Q=391 (at 1.610 GHz) and T=17.7%. [ABSTRACT FROM AUTHOR]