High quality factor microwave dielectric ceramics in the (Mg 1/3 Nb 2/3 )O 2 –ZrO 2 –TiO 2 ternary system

Novel high quality factor microwave dielectric ceramics (1− x )ZrTiO 4 − x (Mg 1/3 Nb 2/3 )TiO 4 (0.325≤ x ≤0.4) and (ZrTi) 1− y (Mg 1/3 Nb 2/3 ) y O 4 (0.2≤ y ≤0.5) with the addition of 0.5 wt% Mn CO 3 in the (Mg 1/3 Nb 2/3 )O 2 –ZrO 2 –TiO 2 ternary system were prepared, using solid‐state reaction method. The relationship between the structure and microwave dielectric properties of the ceramics was studied. The XRD patterns of the sintered samples reveal the main phase belonged to α‐PbO 2 ‐type structure. Raman spectroscopy and infrared reflectivity ( IR ) spectra were employed to evaluate phonon modes of ceramics. The 0.65ZrTiO 4 −0.35(Mg 1/3 Nb 2/3 )TiO 4 −0.5 wt% Mn CO 3 ceramic can be well densified at 1240°C for 2 hours and exhibits good microwave dielectric properties with a relative permittivity (ε r ) of 42.5, a quality factor ( Q × f ) value of 43 520 GHz (at 5.9 Ghz) and temperature coefficient of resonant frequency (τ f ) value of −5ppm/°C. Furthermore, the (ZrTi) 0.7 (Mg 1/3 Nb 2/3 ) 0.3 O 4 −0.5 wt% Mn CO 3 ceramic sintered at 1260°C for 2 hours possesses a ε r of 31.8, a Q×f value of 35 640 GHz (at 6.3 GHz) and a near zero τ f value of −5.9 ppm/°C. The results demonstrated that the (Mg 1/3 Nb 2/3 )O 2 –ZrO 2 –TiO 2 ternary system with excellent properties was a promising material for microwave electronic device applications.