Microwave dielectric properties of La3Ti2TaO11 ceramics with perovskite-like layered structure

The first characterization of the microwave dielectric properties of the La3Ti2TaO11 ceramics is presented. An ordinarily sintered ceramic at 1560 °C exhibits good microwave dielectric properties with ɛr = 46, Q × f = 7500 GHz and τf = −47 ppm/°C. An alternative approach to tailor the temperature coefficient of resonate frequency of La3Ti2TaO11 ceramics is also presented. Textured La3Ti2TaO11 ceramics were fabricated using spark plasma sintering (SPS). By controlling the sintering temperature, orientation degree increased together with the steadily increase in ɛr and Q × f. A noteworthy change in τf from −43.1 ppm/°C to −13.6 ppm/°C with increasing orientation degree was observed. These results suggest that grain-orientation control was an effective way to tailor the microwave dielectric properties of La3Ti2TaO11 ceramics.