Microstructure and Microwave Dielectric Properties of Low- Temperature Sintering Ca5-yLi2yNi4(VO4)6 Ceramics

The influence of sintering temperature and the quantity of lithium content on microstructure and microwave dielectric properties of the Ca5-yLi2yNi4(VO4)6 were investigated. All samples were fabricated by the solid-state reaction method with a sintering temperature of 935 °C-995 °C for 4 h. The results showed no second phases formed from the XRD pattern in all samples and dense surface morphology with a sintering temperature of 965 °C. For specimens with y = 0.10 sintered at 965 °C, the permittivity, quality factor (Qf), and temperature coefficient of resonant frequency (τf) were 9.7, 25,000 GHz -52 ppm/°C, respectively. Thus, these modified dielectric materials possess a high potential for applications in low-temperature co-fired ceramic.