Improved sinterability and temperature stability in Zn2+/Ti4+-co-substituted CaAl2O4 ceramics and their 5G antenna applications
Improved sinterability and temperature stability in Zn2+/Ti4+-co-substituted CaAl2O4 ceramics and their 5G antenna applications
复制标题
改善 Zn2 /Ti4 共取代 CaAl2O4 陶瓷及其 5G 天线应用的可烧结性和温度稳定性
DOI：
10.1007/s10854-021-06362-y
复制
发表时间：
2021-06-16
影响因子：
2.8
通讯作者：
Liu, Bing
中科院分区：
文献类型：
--
作者：
Jin, Ding Hao;Hu, Cheng Chao;Liu, Bing
通过标准固相反应方法制备了低介电常数CaAl2 - 2xZnxTixO4 (x = 0.05, 0.10, 0.15)陶瓷。 (Zn0.5Ti0.5)(3+)部分共取代Al3+可有效降低CaAl2O4陶瓷的烧结温度约200℃，同时可同时将CaAl2O4陶瓷的谐振频率大负温度系数(tau(f)=-55ppm/℃)修正为零。随着 x 的增加，由于 ZnAl2O4 和 CaTiO3 第二相的出现，品质因数 (Q(f)) 呈下降趋势。当 x = 0.15 时，可实现最佳微波介电特性（epsilon(r) = 11.9、Q(f) = 28,090 GHz 和 tau(f) = - 1.2 ppm/℃）。此外，使用x = 0.15陶瓷作为介电基板制作了微带贴片天线。制造的天线在 4.9 GHz 时的 S-11 值为 - 17.8 dB，测量的带宽为 - 10 dB 86 MHz。良好的天线性能表明目前的陶瓷是 6 GHz 以下频段 5G 天线应用的良好候选材料。
CaAl2 - 2xZnxTixO4 (x = 0.05, 0.10, 0.15) ceramics with low permittivity have been prepared via a standard solid-state reaction method. The partial co-substitution of (Zn0.5Ti0.5)(3+) for Al3+ can effectively lower the sintering temperature of CaAl2O4 ceramics by approximately 200 degrees C. Meanwhile, the large negative temperature coefficient of resonant frequency (tau(f) = - 55 ppm/degrees C) of CaAl2O4 ceramics can be simultaneously modified toward zero. With increasing x, the quality factor (Q(f)) indicates a downward changing trend owing to the appearance of ZnAl2O4 and CaTiO3 secondary phases. The optimum microwave dielectric properties (epsilon(r) = 11.9, Q(f) = 28,090 GHz, and tau(f) = - 1.2 ppm/degrees C) are achieved at x = 0.15. Moreover, a microstrip patch antenna is fabricated using the x = 0.15 ceramic as the dielectric substrate. The fabricated antenna demonstrates a S-11 value of - 17.8 dB at 4.9 GHz and a measured - 10 dB bandwidth of 86 MHz. The good antenna performances suggest that the present ceramics are good candidates for 5G antenna applications at the sub-6 GHz band.