Low temperature fired Ln2Zr3(MoO4)9 (Ln=Sm, Nd) microwave dielectric ceramics

A series of new microwave dielectric ceramics Ln(2)Zr(3)(MoO4)(9) (Ln=Sm (SZM), Nd (NZM)) was successfully fabricated by a standard solid-state reaction method. The X-ray diffraction and Rietveld refinement results demonstrate that pure-phase SZM and NZM ceramics belong to the hexagonal system with a space group Ric. Scanning electron microscopy results reveal dense and homogeneous microstructures of these two ceramics as sintered at their respective optimum sintering temperature. Furthermore, the SZM and NZM ceramics sintered at 875 degrees C for 4 h and 850 degrees C for 4 h possess excellent microwave dielectric properties of dielectric permittivity epsilon(r) similar to 11.0, quality factor Qxf similar to 74,012 GHz (10.6 GHz), and temperature coefficient of resonance frequency tau(f) similar to - 45.3 ppm/degrees C, and epsilon(r) similar to 10.8, Qxf similar to 58,942 GHz (10.5 GHz), and tau(f) similar to - 40.9 ppm/degrees C, respectively. These experimental results show great potentials for applications of low temperature co-fired ceramic technology.