Low sintering temperature of (Zn 0.65Mg 0.35)TiO 3– xCaTiO 3-based dielectric with controlled temperature coefficient

Abstract

(Zn 0.65Mg 0.35)TiO 3– xCaTiO 3-based dielectric ceramics sintered at low temperature thanks to ZnO–B 2O 3 glass phase addition are investigated. The effects of such additions on the dilatometric curves, the microstructure, the phase composition and the dielectric properties have been carefully examined. It is shown that the sintering temperature is significantly lowered to 930 °C by the addition of 2 wt.% of ZnO–B 2O 3 glass phase. The temperature coefficient of permittivity ( τ ɛ) could be controlled by varying the CaTiO 3 content and lead to near zero τ ɛ value. As an optimal composition, (Zn 0.65Mg 0.35)TiO 3 + 7%CaTiO 3, co-sinterable with silver electrodes at 930 °C, exhibits at 1 MHz, a relative permittivity of ɛ r = 21, a temperature coefficient of the permittivity τ ɛ of −4 ppm/°C and low dielectric losses (tan( δ) < 10 −3). These interesting properties make this system promising to manufacture Ag-based electrodes multilayer dielectric devices.