High temperature stability of the dielectric and insulating properties of Ca(Ti, Zr)SiO₅ ceramics Available to Purchase

Useful dielectric properties for high-temperature ceramic capacitors are demonstrated in a non-perovskite oxide, Ca(Ti_0.85 Zr_0.15)SiO₅, which is mainly composed of one-dimensional chains of oxygen octahedra that are mutually linked by SiO₄ tetrahedra. Its dielectric constant and low temperature coefficient of capacitance were found to be 43 and −102 ppm/K, respectively, over the wide temperature range of 300–780 K. The high insulating performance was also indicated by the high resistivity, exceeding 10¹¹ Ω cm up to 523 K. The systematic dielectric measurements for Ca(Ti_1−x Zr_x)SiO₅ as functions of the composition and temperature indicate that the suppression of the anti-ferroelectric phase transition of CaTiSiO₅ by Zr⁴⁺-substitution is a key to improve the temperature-stability and the high-resistivity in Ca(Ti_1−x Zr_x)SiO₅. The present results shed light on the development of a designing principle for ceramic capacitors for the high-temperature use.