Synthesis, low temperature co-firing, and microwave dielectric properties of two ceramics BiM2VO6 (M=Cu, Ca)

Abstract

Two microwave dielectric ceramics, BiCu2VO6 and BiCa2VO6, with low sintering temperatures were prepared by a sol–gel method and conventional solid-state reaction method, respectively. The BiCu2VO6 ceramic could be well densified at around 675°C with a relative permittivity ~18.199, a Q×f value ~7775GHz (at 7.7075GHz), and a negative temperature coefficient of resonant frequency approximately −177.3ppm/°C. The BiCa2VO6 ceramic could be well densified at around 900°C and demonstrated high performance microwave dielectric properties with a less relative permittivity ~9.884, a greater Q×f value ~23,580GHz (at 9.93GHz), and a temperature coefficient of resonant frequency approximately −71.4ppm/°C. From the X-ray diffraction patterns, backscattered electron image and energy dispersive spectra analysis results of the co-fired samples with 20wt% Ag additive, the BiCu2VO6 and BiCa2VO6 ceramics did not react with Ag powders at their optimum sintering temperature.