Preparation, crystal structure, and dielectric characterization of Li2W2O7 ceramic at RF and microwave frequency range

Abstract

Single phase Li2W2O7 with anorthic structure was prepared by the conventional solid-state reaction method at 550°C and the anorthic structure was stable up to 660°C. The dielectric properties at radio frequency (RF) and microwave frequency range were characterized. The sample sintered at 640°C exhibited the optimum microwave dielectric properties with a relative permittivity of 12.2, a quality factor value of 17,700 GHz (at 9.8 GHz), and a temperature coefficient of the resonant frequency of −232 ppm/°C as well as a high relative density ~94.1%. Chemical compatibility measurement indicated Li2W2O7 did not react with aluminum electrodes when sintered at 640°C for 4 h.