Temperature-stable dielectric ceramics with nominal composition of Ca6Ti2Ta8O30

Abstract The dielectric ceramics with nominal composition of Ca 6 Ti 2 Ta 8 O 30 were synthesized and characterized. The cubic CaTa 2 O 6 major phase combined with minor amount of CaTiO 3 were formed in the present ceramics, and this differed from the similar compositions of Ba 6 Ti 2 Ta 8 O 30 and Sr 6 Ti 2 Ta 8 O 30 , which had the filled tungsten bronze structure. The present ceramics indicated a high dielectric constant of 85–86 with a small temperature coefficient of dielectric constant of +24–29 ppm/°C together with a dielectric loss of 0.0056–0.0060 (at 1 MHz). The dielectric constant was almost a constant, while the dielectric loss and temperature coefficient of dielectric constant were sensitive to the sintering conditions. The present ceramics might be promising in temperature compensated capacitor applications.