Microwave dielectric properties of (Bi1−xFex)NbO4 ceramics prepared by the sol–gel method

Abstract (Bi 1− x Fe x )NbO 4 ( x =0.00, 0.25, 0.50 and 0.75) samples were prepared using the sol–gel method. The fine particles were pressed into cylinders and then treated at temperatures between 350 and 650 °C. The structure was studied by X-ray diffraction and the morphology by scanning electron microscopy. The measurements of the complex permittivity were made in a resonant cavity, using the small perturbation method, at frequencies of 2.7 and 5.0 GHz. The inclusion of iron allowed a significant decrease in the dielectric losses and more important is to note that it permitted a reduction of the sintering temperature.