Low-Temperature Sintering Microwave Characteristics of B_2O_3-doped CaLa_4Ti_4O_15 Dielectric Ceramics

摘要

Preparation and microwave dielectric properties of B_2O_3-doped CaLa_4Ti_4O_(15) ceramics have been investigated. X-ray diffraction data show that CaLa_4Ti_4O_(15) ceramic has a trigonal structure coupled with a second phase of CaLa_4Ti_5O_(17). The CaLa_4Ti_4O_(15) ceramic with addition of 0.5 wt% B_2O_3, sintered at 1220℃ for 4 h, exhibits microwave dielectric properties with a dielectric constant of 45.8, Q ×f value of 24,000 GHz, and temperature coefficient of resonant frequency (τ_f) of - 19 ppm/℃. B_2O_3-doped CaLa_4Ti_4O_(15)ceramics, which have better sintering behavior (decrease in sintering temperature ～ 330℃) and dielectric properties than pure CaLa_4Ti_4O_(15) ceramics, are candidates for applications in microwave devices.