Microwave dielectric properties of temperature‐stable (Na0.5Bi0.5)MoO4–SrMoO4 ceramics sintered at ultra‐low temperature

Abstract Ever‐growing wireless communication industry demands low loss dielectric ceramics with exceptional microwave dielectric properties and ultra‐low sintering temperatures. In this work, a solid solution (1 − x )Na 0.5 Bi 0.5 MoO 4 – x SrMoO 4 referred as (1 − x )NBM– x SM ( x = 0.4–0.9) was prepared through replacing (NaBi) 2+ by Sr 2+ . X‐ray diffraction analysis (XRD) revealed a solid solution ceramics characterized by a tetragonal scheelite structure. Scanning electron microscopy (SEM) and relative density further confirmed the formation of low porosity and high density scheelite solid solution ceramics. Optimum microwave dielectric performance with a relative permittivity of 15.48, value of 18 763 GHz and a near‐zero temperature coefficient of resonant frequency ( = +2.7 ppm/°C) was achieved at x = 0.7 composition with ultra‐low sintering temperature of 660°C. In order to validate its microwave device application, a prototype dielectric resonator antenna (DRA) was fabricated using the 0.3NBM–0.7SM ceramic. DRA showcased excellent radiation performance, with impedance bandwidth of 200 MHz at a working frequency of 6.83 GHz and realized gain of 5.66 dBi. The co‐firing investigations demonstrate Ag powder exhibits excellent chemical compatibility with the (1 − x )NBM– x SM ceramics, confirming a promising potential of the (1 − x )NBM– x SM ( x = 0.4–0.9) solid solution ceramics for ultra‐low temperature co‐fired ceramics‐based microwave application.