High Dielectric Constant and Low‐Loss Microwave Dielectric Ceramics Using (Zn _0.95 M ²⁺ _0.05 )Ta ₂ O ₆ (M ²⁺ =Mn, Mg, and Ni) Solid Solutions

Abstract

High dielectric constant and low‐loss ceramics in the (Zn 0.95 M 2+ 0.05 )Ta 2 O 6 (M 2+ =Mn, Mg, and Ni) ceramic family have been prepared by the conventional mixed‐oxide route and their crystal structures and microwave dielectric properties have been investigated. The forming of (Zn 0.95 M 2+ 0.05 )Ta 2 O 6 (M 2+ =Mn, Mg, and Ni) solid solutions was confirmed by the X‐ray diffraction patterns, high‐resolution transmission electron microscopic lattice images, the energy‐dispersive X‐ray analysis, and the measured lattice parameters. The dielectric properties exhibited a significant dependence on the sintering condition and crystal structure of the ceramics. A fine combination of microwave dielectric properties can be achieved in the (Zn 0.95 Mn 0.05 )Ta 2 O 6 ceramics sintered at 1325°C for 2 h with a dielectric constant of ∼38.56, a Q × f value of ∼92 700 GHz (where f =7.64 GHz, is the resonant frequency), and a temperature coefficient of resonant frequency (τ f ) of ∼8.9 ppm/°C. It is proposed as a suitable candidate material for small‐sized global positioning system patch antennas.