Li2Zn2W2O9: A novel low-temperature sintering microwave dielectric ceramic with corundum structure

A microwave dielectric ceramic Li2Zn2W2O9 with corundum structure was prepared through the solid state reaction method. The crystal structure was investigated using the Rietveld refinement. The sintering behavior, microwave dielectric properties, and chemical compatibility with silver electrodes of Li2Zn2W2O9 ceramic were studied in detail using X-ray diffraction, energy-dispersive spectrometer, and dielectric measurement. The Li2Zn2W2O9 ceramic could be well densified at relatively low sintering temperature range 790-830 degrees C. The optimum microwave dielectric performance, with a Q x f value similar to 15,710 GHz (at 9.7 GHz), a relative permittivity similar to 14.7, and a temperature coefficient of resonant frequency similar to-76.8 ppm/degrees C, was obtained when sintered at 790 degrees C. XRD and EDS analysis of the co-fired sample confirmed the chemical compatibility of Li2Zn2W2O9 with silver electrodes. These merits make the Li2Zn2W2O9 ceramic a possible candidate for LTCC applications. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.