Abstract
Complex perovskite ceramics, the system Sr(Ni1/3Nb2/3)O3(SNN)–Ba(Ni1/3Nb2/3)O3(BNN) system, have been studied in view of finding materials for use as dielectric resonators at microwave frequencies. A nearly zero temperature coefficient of resonant frequency is obtained for solid solution ceramics with 0.73SNN–0.27BNN composition which corresponds to the order-disorder phase boundary. The relative densities of those ceramics sintered in O2 atmosphere are more than 99.5%, while those sintered in air are 97∼98.5%. The dielectric constant and the unloaded Q of the ceramics sintered in O2 atmosphere are 34 and 10,000 at 10 GHz respectively.