A low-permittivity microwave dielectric ceramic BaZnP2O7 and its performance modification

Complex pyrophosphates compounds have attracted much attention as promising candidates for substrate applications. In the work, a low-permittivity BaZnP2O7 ceramic was synthesized through solid-state reaction. The pure phase BaZnP2O7 was crystallized in the triclinic P-1 space group. Excellent microwave dielectric properties of the BaZnP2O7 ceramic with epsilon(r) = 8.23, Qf = 56170 GHz, and tau(f) = -28.7 ppm/degrees C were obtained at 870 degrees C for 4 h. The substitution of Mg2+ for Zn2+ was found to have positive effects on grain morphology and dielectric properties. Optimized performance of epsilon(r) = 8.21, Qf = 84760 GHz, and tau(f) = -21.9 ppm/degrees C was yielded at 900 degrees C for the BaZn0.98Mg0.02P2O7 ceramic. Intrinsic dielectric properties of BaZn1-xMgxP2O7 ceramics were studied via Clausius-Mossotti equation and complex chemical bond theory.