A novel low sintering temperature scheelite-structured CaBiVMoO8 microwave dielectric ceramics

Abstract Novel medium-permittivity scheelite-structured CaBiVMoO8 ceramics were prepared by a solid-state reaction route. The effects of sintering temperature on the phase composition, microstructure and microwave dielectric properties of CaBiVMoO8 ceramics were investigated systematically. The Rietveld refinements of X-ray data revealed all samples were well crystallized in space group I41/a. All the samples exhibited a closely packed grain morphology and discernable grain boundaries. The relationship between microwave dielectric properties and bulk density of samples at different sintering temperatures was further researched. Besides, the lattice energy was one of the important factors affecting the Q×f values of CaBiVMoO8 ceramics. The temperature coefficient of resonant frequency (τf) could be slightly affected by sintering temperature. The CaBiVMoO8 ceramics were expected to be applied to low temperature co-fired ceramics technology. In this paper, the CaBiVMoO8 ceramics exhibited excellent properties sintered at 850 °C for 4h: er ∼40.55, Q×f ∼16,670 GHz, τf ∼ +55.90 ppm/°C.