High‐Energy Density Dielectrics and Capacitors for Elevated Temperatures: Ca(Zr,Ti)O3

Abstract

The Ca(Zr1−xTix)O3 (CZT) solid solution system is a linear dielectric that is of interest for high‐temperature power capacitor applications. This dielectric was synthesized by conventional solid‐state processes and prototyped into single‐layer CZT capacitors, which were fabricated with interdigitated electrodes cofired between dielectric layers ~10‐μm thick. The dielectric properties of these capacitors were extensively investigated as a function of Zr/Ti ratio on the CaZrO3 side of the solid solution. The electrostatic energy density and breakdown strength of the CZT capacitors were investigated by measuring polarization–electric field curves as a function of temperature from room temperature to 250°C. The Ca(Zr0.80Ti0.20)O3 capacitors show high electrostatic energy density of 4 J/cm3 at 250°C. Highly accelerated life testing (HALT) was also performed on these dielectrics, and we quantified the thermal stimulated depolarization current (TSDC) to access the major point defects in the CZT system.