Microwave dielectric properties of (A2+ 1/3B5+ 2/3)0.5Ti0.5O2 (A2+ = Zn, Mg, B5+ = Nb, Ta) ceramics

摘要

Dielectric properties of (A2+ 1/3B5+ 2/3)0.5Ti0.5O2 (A2+ = Zn, Mg, B5+ = Nb, Ta) (A2+ = Zn, Mg, B5+ = Nb, Ta) ceramics were investigated at microwave frequencies. A single phase with tetragonal rutile structure was obtained through the entire compositions. Dielectric properties were strongly dependent on the structural characteristics. The specimens with B5+ = Nb showed a larger dielectric constant than those with B5+ = Ta due to the decrease of bond valence. Quality factors (Qf) of the specimens with B5+ = Ta were larger than those with B5+ = Nb. Temperature coefficient of the resonant frequencies (TCF) of (Zn1/3Nb2/3)0.5Ti0.5O2 was larger than that of (Mg1/3Ta2/3)0.5Ti0.5O2. These results could be attributed to the changes of the temperature coefficient of dielectric constant and the degree of oxygen octahedral distortion.