Synthesis of BaTiTe₃O₉ ceramics for LTCC application and its dielectric properties

A new tellurate, BaTiTe₃O₉, was found in the BaO-TiO₂-TeO₂ ternary system. Using conventional solid state reaction, the new single phase compound, BaTiTe₃O₉ phase was synthesized and sintered over the very low temperature range of only 625-700°C. In addition, different calcinations routes, including the effect of TiTe₃O₈ precursor in the phase formation, were examined. The dielectric properties of BaTiTe₃O₉ ceramics were determined in the microwave region as well as at low frequencies. The relative dielectric permittivity (ε_r) and the temperature coefficient of permittivity (TC_ε) of BaTiTe₃O ₉ at 1 MHz were measured as 30 and 790 ppm/°C, respectively. The dielectric properties were maintained up to microwave region without degradation. The dielectric permittivity and Q × f product obtained were 29 and 1,700 GHz at 7.6 GHz, respectively. The temperature coefficient of resonance frequency (TCF) showed a large negative value of -372 ppm/°C.