Raman spectroscopic, infrared spectra and microwave dielectric properties in the (ZrTi)1-x(Al1/2Nb1/2)2xO4 ceramics

A series of (ZrTi)(1-x)(Al1/2Nb1/2)(2x)O-4 (0.12x0.30) ceramics with suitable sintering aids of 0.5wt% CuO were successfully synthesized by the conventional solid-state processing. The XRD analysis suggested that the main crystalline phase of the well-densified ceramics belonged to -PbO2-type structure. The SEM demonstrated that the appropriate sintering aids and the proper sintering temperature led to a densification of the ceramics by observing the microstructure. Raman spectroscopic and Far Infrared reflectivity spectra were applied to explore the relation between microwave dielectric properties and microstructure by learning the phonon vibrational modes. An excellent microwave dielectric properties (epsilon(r)similar to 36.5, Qf similar to 36200GHz, (f)similar to 0ppm/degrees C) was achieved in (ZrTi)(1-x)(Al1/2Nb1/2)(2x)O-4 ceramics sintered at 1350 degrees C for 4h when x=0.18. The results revealed this ceramic system is a very promising candidate for microwave dielectric applications requiring extremely near zero tau(f).