Mg
(1-x)Zn
xTa
2O
6 (x = 0.00?0.08) dielectric ceramics were synthesized via the traditional solid-state reaction method. We used XRD and Rietveld refinement to demonstrate that a pure Mg
(1-x)Zn
xTa
2O
6 phase with trirutile structure was formed. Zn
2+ substitution helped to decrease the Raman full width at half width of the A
1g mode at 703 cm
?1, which resulted in an increase in the order and rigidity of the TaO
6 octahedron, this in turn contributed to improving the Q×f values. Additionally, the introduction of Zn
2+ significantly promoted grain growth and increased the dense, and the molecular polarizability, these factors lead to a higher permittivity. Moreover, enhanced Ta-O bond energy resulted in a more stable TaO
6 octahedron in the Mg
(1?x)Zn
xTa
2O
6 system, which contributed to enhanced
τf values via substitution of Zn
2+ doped on the A-site. Correspondingly, the microwave dielectric properties were significantly improved for 0.04-doped samples, obtaining: ε
r = 27, Q × f = 185,000 GHz (at 7.47 GHz),
τf =32 ppm/°C.
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