Ma Xing-Hua, Qu Qi, Wu Haitao, Zhang Zhenlu, Ma Xingyi
School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520, China.
School of Environmental and Material Engineering, Yantai University, Yantai 264005, China.
Materials (Basel). 2024 Dec 20;17(24):6251. doi: 10.3390/ma17246251.
NbO-type ceramics (where = Mg, Ca, Mn, Co, Ni, Zn and = Ti, Zr) are essential for satellite communication and mobile base stations due to their medium relative permittivity () and high quality factor ( × ). Although ZnTiZrNbO ceramic exhibits impressive microwave dielectric properties, including an of 29.75, a × of 107,303 GHz, and a of -24.41 ppm/°C, its sintering temperature of 1150 °C remains a significant barrier for integration into low-temperature co-fired ceramic (LTCC) technologies. To overcome this limitation, a strategy involving the partial substitution of Zn with Cu and the addition of LiF as a sintering aid was devised for ZnTiZrNbO. The dual impact of Cu partial substitution and LiF as a sintering enhancer facilitated the successful sintering of CuZnTiZrNbO ceramics at a reduced temperature of 950 °C using the conventional solid-state reaction method. These ceramics exhibited excellent microwave dielectric properties. Notably, CuZnTiZrNbO ceramic with 40 mol% LiF addition demonstrated optimal microwave dielectric properties without any reaction with a silver electrode at a sintering temperature of 950 °C, yielding = 32, × = 45,543 GHz, and = -43.5 ppm/°C.
NbO型陶瓷（其中 = Mg、Ca、Mn、Co、Ni、Zn且 = Ti、Zr）因其相对介电常数（）适中以及品质因数（×）较高，对卫星通信和移动基站至关重要。尽管ZnTiZrNbO陶瓷展现出令人印象深刻的微波介电性能，包括介电常数为29.75、品质因数×为107303 GHz以及温度系数为 -24.41 ppm/°C，但其1150°C的烧结温度仍然是集成到低温共烧陶瓷（LTCC）技术中的一个重大障碍。为克服这一限制，针对ZnTiZrNbO设计了一种策略，即部分用Cu替代Zn并添加LiF作为烧结助剂。Cu的部分替代和LiF作为烧结增强剂的双重作用，使得采用传统固态反应法在950°C的降低温度下成功烧结了CuZnTiZrNbO陶瓷。这些陶瓷表现出优异的微波介电性能。值得注意的是，添加40 mol% LiF的CuZnTiZrNbO陶瓷在950°C的烧结温度下表现出最佳微波介电性能，且与银电极无任何反应，介电常数 = 32、品质因数× = 45543 GHz以及温度系数 = -43.5 ppm/°C。
