Effect of CuO additives on sintering and dielectric behaviors of CeO2 ceramics

The effects of CuO addition (1 and 2 wt%) on microstructures and microwave dielectric properties of CeO2 ceramics with CuO additions have been investigated. It is found that CeO2 ceramics can be sintered at 1490 °C due to the liquid phase effect of CuO addition. At 1580 °C, CeO2 ceramics with 1 wt% CuO addition possesses a dielectric constant (ɛr) of 21.7, a Q × f value of 50,000 (at 9GHz) and a temperature coefficient of resonant frequency (τf) of −59 ppm/°C. A large sintering temperature reduction (about 200 °C) can be achieved by adding CuO to the CeO2 ceramics. The CuO–added CeO2 ceramics can find applications in microwave devices.