Spinel-olivine microwave dielectric ceramics with low sintering temperature and high quality factor for 5 GHz wi-fi antennas

The patch antenna of spinel-olivine composite ceramic (Li2ZnGe3O8-Li2ZnGeO4) is designed, which can realize power ratio (59%) and S11 of -14 dB at 5.7 GHz. The low sintering temperature (< 960 °C), low relative permittivity (8.15) and good microwave dielectric properties (quality factor ~ 32,500 GHz, resonant frequency temperature coefficient ~ -74.8 ppm/ °C) were obtained for spinel-olivine composite ceramic. Li2ZnGe3O8-Li2ZnGeO4 composite microwave dielectric ceramics were synthesized at 900–980 °C using Li2CO3, ZnO and GeO2, which can co-fire with silver electrodes without chemical reaction. These exceptional characteristics enable high-speed signal transmission application of spinel-olivine composite ceramics (Li2ZnGe3O8-Li2ZnGeO4) in 5 GHz Wi-Fi antennas.