(Ca1−xMgx)SiO3: A low-permittivity microwave dielectric ceramic system

A low-permittivity microwave dielectric ceramic system (Ca1−xMgx) SiO3 was investigated. The effects of Mg and Ca substitutions in the A-site on the crystal structure and microwave dielectric properties were studied. Specimens with compositions of x = 0.1, 0.5 and 0.9 were single-phased. The secondary phases that decrease the Qf values were observed in specimens with other compositions. Single-phased ceramics had relatively higher Qf values. When x = 0.1, the specimen sintered at 1290 °C for 2 h exhibited excellent properties of ɛr = 6.49, Qf = 62,420 GHz and τf = −43.3 ppm/°C.