Effect of nonstoichiometry on the structure and microwave dielectric properties of Ba 1 − x (Zn 1/2 W 1/2 )O 3 − x and Ba(Zn 1/2 − y W 1/2 )O 3 − y /2

We have synthesized Ba1 − x (Zn1/2W1/2)O3 − x and Ba(Zn1/2 − y W1/2)O3 − y/2 barium tungstates with different deviations from cation stoichiometry (x = 0.01–0.05, y = 0.01–0.05), determined the phase composition of ceramics fabricated from the tungstates, and investigated their electrical properties. Even slight deviations from cation stoichiometry in Ba(Zn1/2W1/2)O3 lead to the formation of the scheelite phase BaWO4, and its content increases with heat-treatment temperature. Barium or zinc deficiency in the systems studied improves the sintering behavior of Ba(Zn1/2W1/2)O3 and increases the degree of 1: 1 B-site cation ordering, which in turn ensures an increase in microwave quality factor, Q.