A temperature stable microwave dielectric material Ni0.35Zn0.65TiNb2O8

Abstract

A temperature stable, high quality, low sintering temperature microwave dielectric material Ni0.35Zn0.65TiNb2O8 was investigated for the first time. The compounds were prepared by a conventional mixed-oxide route and sintered at the temperature range of 1,060–1,140 °C. The microstructure and microwave dielectric properties were investigated systematically. The X-ray diffraction results show that the Ni0.35Zn0.65TiNb2O8 ceramics contained two phase: ZnTiNb2O8 phase and Zn0.17Nb0.33Ti0.5O2 phase. With increase in temperature, the amount of ZnTiNb2O8 phase decreased and that of Zn0.17Nb0.33Ti0.5O2 increased. The microwave dielectric properties of Ni0.35Zn0.65TiNb2O8 were mainly affected by the variation of content and crystal structure of each phase. With increasing temperature, the content of Zn0.17Nb0.33Ti0.5O2 phase increased, resulting in the increasing dielectric constant and τ f , and decreasing Qf value. In addition, the dielectric constant increased with increasing bulk density, the Qf value were related to the cell volume of each phase, and the τ f value had correlation with the bond valence of each phase. Outstanding microwave dielectric properties of e = 40.9, Qf = 40,870 GHz, especially near-zero τ f = 0.62 × 10−6/°C were obtained sintered at 1,100 °C for 6 h. With the relatively low sintering temperature and excellent dielectric properties in microwave range, this material is very promising for electronic devices application.