Microwave dielectric properties of Ba3Ti4−x(Zn1/3Nb2/3)xNb4O21 for low temperature co-fired ceramics

The effects of substitution of (Zn1/3Nb2/3) for Ti on the sintering behavior and microwave dielectric properties of Ba3Ti4−x(Zn1/3Nb2/3)xNb4O21 (0 ≤ x ≤ 4) ceramics have been investigated. The dielectric constant (ɛr) and the temperature coefficient of the resonant frequency (τf) of Ba3Ti4−x(Zn1/3Nb2/3)xNb4O21 ceramics decreased with increasing x. However, the Q × f values enhanced with the substitution of (Zn1/3Nb2/3) for Ti. It was found that a small amount of MnCO3–CuO (MC) and ZnO–B2O3–SiO2 (ZBS) glass additives to Ba3Ti4−x(Zn1/3Nb2/3)xNb4O21 (x = 2) ceramics lowered the sintering temperature from 1250 to 900 °C. And Ba3Ti4−x(Zn1/3Nb2/3)xNb4O21 (x = 2) ceramics with 1 wt% MC and 1 wt% ZBS sintered at 900 °C for 2 h showed excellent dielectric properties: ɛr = 53, Q × f = 14,600 GHz, τf = 6 ppm/°C. Moreover, it has a chemical compatibility with silver, which made it as a promising material for low temperature co-fired ceramics technology application.