Temperature stable Li2Ti0.75(Mg1/3Nb2/3)(0.25)O-3-based microwave dielectric ceramics with low sintering temperature and ultra -low dielectric loss for dielectric resonator antenna applications

摘要

Microwave dieLectric ceramics are considered to be one of the key materials of dieLectric resonators/ filters and have wide application prospects in fifth generation (5G) mobile communication systems. Here we prepared two kinds of [ow -sintering temperature and high-performance microwave dieLectric ceramics with monoclinic rock salt structure by adding a small amount of V205 and 0.6Cu0-0.413203 sintering aids to Li2T10.75(Mgii3Nb2/3)o.2503 (LTMN0.25). The sintering temperature of LTMN0.25 ceramics with 2 wt% V205 and 1 wt% 0.6CuO-0.4B203 additions could be effectively reduced from 1170 C to below 910 C due to the Liquid phase effects resulting from the additives. Typically, high performance microwave dieLectric properties can be obtained in the LTMN0.25 + 2 wt% V205 ceramic sintered at 910 C for 2 h, with a cr - 20.7, a Q x f- 60 460 GHz and a TCF - +4.3 ppm C-1. The best dieLectric properties of cr - 19.9, a Q x f- 60 950 GHz and a TCF - -6.1 ppm C-1 were obtained for the samples with 1 wt% 0.6CuO-0.4B203 sintered at 870 C for 2 h. A prototype dieLectric resonator antenna (DRA) was fabricated by LTMN0.25 + 1 wt% 0.6CuO-0.4B203 ceramic. The antenna resonated at 10.02 GHz with a bandwidth -.175 MHz at -10 dB transmission Loss (Su). Moreover, the chemical compatibility with Ag powder suggests that the LTMN0.25 + 2 wt% V205 and LTMN0.25 + 1 wt% 0.6CuO-0.4B203 ceramics may be suitable candidates for Low temperature co -fired ceramic technology applications.