Enhanced effect of non-stoichiometry on the sinterability and microwave dielectric properties of Mg2+xSnO4 ceramics

Mg 2+ x SnO 4 microwave dielectric ceramics were prepared by the solid state reaction method. The effect of Mg non-stoichiometry on the sintering behavior, phase structure and microwave dielectric properties of Mg 2+ x SnO 4 ceramics was investigated. The sinterability and microwave dielectric properties were improved for the samples with slightly excessive amount of Mg ( x ≤ 0.15). Especially, the quality factor ( Q × f ) was significantly enhanced compared with the stoichiometric Mg 2 SnO 4 ( Q × f = 45, 300 GHz). The best overall performance was obtained for the Mg 2.15 SnO 4 ceramics sintered at 1,620 °C for 4 h ( ε r = 7.42, Q × f = 76,800 GHz, τ f = −50 ppm/ °C); this suggests a potential for applications in the millimeter wave range.