BaO–TiO2 microwave ceramics

In this paper, the structure and dielectric properties of BaO–TiO2 system ceramics were studied. By adding ZnO and Nb2O5 as sintering agents to the raw materials, the BaO–TiO2 system ceramics were sintered at a temperature of 1260 °C for 2 h and have superior dielectric properties at 1 GHz: quality factor Q=12,500, relative dielectric constant εr≈37, temperature coefficient of dielectric constant αε=0±30 ppm/°C. XRD pattern shows that the main crystal phase of the ceramics is Ba2Ti9O20, accompanied by a small number of additional phases: BaTi4O9, Ba4Ti13Zn7O34, Ba4Ti13O30 and Ti2Nb10O29, etc. The initial Ba/Ti ratio has a great effect on the dielectric properties of the ceramics, which can be explained by the variance in the formation of phases due to different Ba/Ti ratios.