Novel Series of Low-Firing Microwave Dielectric Ceramics: (1-x)Li_3Bi_2P_3O_(12)-xTiO_2

摘要

A new thermally stable microwave dielectric ceramic with low-firing temperature in (1-x)Li_3Bi_2P-3O_(12)-xTiO_2 [(1-x) LBP-xT, 0 ≤ x ≤ 0.6] ceramics system was obtained using conventional solid-state reaction method. The phase transformation, microstructure, and microwave dielectric properties of materials were investigated using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) , and a network analyzer. The LBP ceramic (x = 0) sintered at 725℃ has optimum microwave dielectric properties with relative permittivity (ε-r) of 15.8, Q × f of 26 600 GHz and temperature coefficients of resonant frequency (τ_f) of -130 ppm/℃. The ε_r and τ_f of (1-x)LBP-xT ceramics were tailored with increasing x values. At x = 0.55, the ceramic exhibits improved microwave dielectric properties with ε_r = 22.1, Q × f= 14 900 GHz and τ_f = -2.6 ppm/℃.