Effect of ZnO doping on the microwave dielectric properties of LnTiNbO6 (Ln=Sm or Dy) ceramics

LnTiNbO6 (Ln = Sm or Dy) ceramics, doped with ZnO, were prepared by the solid-state ceramic route. The cylindrical samples were sintered at between 1260 and 1385 C. The densities were measured using the Archimedes method. Samples were characterised by XRD and SEM. Microwave dielectric properties of the cylindrical samples were measured using the network analyser. Doping of ZnO reduced the sintering temperature and increased the dielectric constant. The variation of the resonant frequency with respect to temperature was reduced with the increase in doping concentration. The unloaded quality factor was also improved for low doping concentrations. These materials can be used as dielectric resonators in microwave circuits. 21 refs.