Microwave Dielectric Properties of the (1−x)La_2⁄3TiO₃–xLa(Ti_1⁄2Mg_1⁄2)O₃ System

Abstract

(1−x)La_2⁄3TiO₃–xLa(Mg_1⁄2Ti_1⁄2)O₃ ceramics with x ranging from 0.1 to 0.9 were prepared by conventional solid-state reaction. La_2⁄3TiO₃ and La(Mg_1⁄2Ti_1⁄2)O₃ were found to form a solid solution over the whole compositional range. However, the second phase La₂Ti₂O₇ existed for x=0.1 and 0.3. As the x value increased from 0.1 to 0.9, the dielectric constant ε_r decreased from 65.1 to 28.4. The oxygen vacancies were the main factor affecting the Q×f values of the (1−x)La_2⁄3TiO₃–xLa(Mg_1⁄2Ti_1⁄2)O₃ ceramics. A τ_f value of −5 ppm/°C can be obtained at x=0.3.