Microwave Loss Quality of BaZn ₁₃ Ta 2/3 O ₃ Ceramics

Loss of ZnO explains the improved microwave loss quality (Q) for Ba(Zn 1/3 Ta 2/3 )O 3 ceramics which have been sintered at high temperatures or longer times. Ordering of Zn and Ta is complete in 60 h at 1400°C, but crystallographic distortion and Q continue to increase up to 120 h. As ZnO volatilizes from the sample, Ba replaces Zn on the B sites and permits additional crystallographic distortion; meanwhile, barium tantalate phases also appear. Crystallographic compositional data are presented to confirm this interpretation.