Enhanced effect of non-stoichiometry on the sinterability and microwave dielectric properties of Mg2+x SnO4 ceramics

Mg2+x SnO4 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 Mg2+x SnO4 ceramics was investigated. The sinterability and microwave dielectric properties were improved for the samples with slightly excessive amount of Mg (x a parts per thousand currency sign 0.15). Especially, the quality factor (Q x f) was significantly enhanced compared with the stoichiometric Mg2SnO4 (Q x f = 45, 300 GHz). The best overall performance was obtained for the Mg2.15SnO4 ceramics sintered at 1,620 A degrees C for 4 h (epsilon (r) = 7.42, Q x f = 76,800 GHz, tau (f) = -50 ppm/ A degrees C); this suggests a potential for applications in the millimeter wave range.