Effects of F− substitution on the enhanced microwave dielectric properties of MgTa2O6 ceramics

Ion substitution engineering is an effective procedure in refining the crystal structure and performance for the microwave dielectric ceramics . In this study, MgTa 2 O 6- x F 2 x ( x  = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6) ceramics were synthesized using the conventional solid-phase reaction method. The effects of F − substitution for O 2− in MgTa 2 O 6 matrix were systematically investigated. The correlations between the crystal structure and the microwave dielectric properties were analyzed. The solution of F − into the oxygen sites was confirmed by the XRD and Raman spectra. The introduction of F − improved the morphology as well as the stability of the crystal structure significantly, which successfully depressed the electromagnetic wave loss through the bulk and enhanced the quality factor ( Q  ×  f ) by nearly 50%, reaching up to 179,000 GHz (7.15 GHz) in the sample of x  = 0.4 at the sintering temperature of 1425 °C.