Synthesis and microwave dielectric properties of Li2ZnTi3O8 ceramics by the reaction-sintering process

Li2ZnTi3O8 ceramics were prepared by reaction-sintering process (calcination free). The crystal phase and microstructure were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). A pure phase of Li2ZnTi3O8 ceramics sintered at 1075 degrees C-1150 degrees C with cubic spinel structure was confirmed by XRD. The microwave dielectric properties (epsilon(r), Qxf) of Li2ZnTi3O8 ceramics were strongly dependent on the densification and grain size. The tau(f) of Li2ZnTi3O8 ceramics was almost independent with the sintering temperatures. In particular, Li2ZnTi3O8 ceramics by reaction-sintering method sintered at 1125 degrees C for 5 hrs exhibited good combination microwave dielectric properties of epsilon(r) = 21.7, Q x f = 70 500 GHz (at 7.5 GHz) and tau(f)=-13 ppm/degrees C.