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 in the solid-state ceramic route. The cylindrical samples were sintered at temperatures between 1260 and 1385 °C. The densities were measured using Archimedes method. Samples were characterized by X-ray diffraction and scanning electron microscopic methods. Microwave dielectric properties of the cylindrical samples were measured using the network analyzer. Doping of ZnO reduced the sintering temperature and increased the dielectric constant (εr). The variation of the resonant frequency with respect to temperature was reduced with the increase in doping concentration. The unloaded quality factor (Qu × f) is also improved for low doping concentrations. These materials can be used as dielectric resonators in microwave circuits.