Novel wodginite structured MnO-SnO2-Ta2O5 microwave dielectric ceramic

New type MnO-SnO2-Ta2O5 ceramic is firstly synthesized by conventional solid-state route. Its novel monoclinic wodginite crystal structure with C2/c space group is innovatively studied in microwave band use. The phase composition, crystal structure and microwave dielectric properties are analyzed. The Q × f value and the temperature coefficient of resonance frequency have strong relationships with cation distribution and bond valence, respectively. On this basis, improved degree of cation ordering is achieved by annealing process in air and makes these ceramics promising for microwave dielectric applications. The typical microwave dielectric properties of MnO-SnO2-Ta2O5 ceramics are: εr = 16.2, Q × f = 21,200 GHz (@9.5 GHz), τf = −45.1 ppm/°C.