Wu Fang-Fang, Zhou Di, Du Chao, Xu Diming, Li Rui-Tao, Zhang Ling, Qiao Feng, Shi Zhong-Qi, Darwish Moustafa Adel, Zhou Tao, Jantunen Heli, Reaney Ian M
Electronic Materials Research Laboratory, Key Laboratory of Multifunctional Materials and Structures, Ministry of Education, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi710049, People's Republic of China.
Microelectronics Research Unit, University of Oulu, Post Office Box 4500, FI-90014Oulu, Finland.
ACS Appl Mater Interfaces. 2022 Nov 2;14(43):48897-48906. doi: 10.1021/acsami.2c14627. Epub 2022 Oct 21.
Vanadium(V)-substituted cerium niobate [Ce(NbV)O, CNV] ceramics were prepared to explore their structure-microwave (MW) property relations and application in C-band dielectric resonator antennas (DRAs). X-ray diffraction and Raman spectroscopy revealed that CNV (0.0 ≤ ≤ 0.4) ceramics exhibited a ferroelastic phase transition at a critical content of V ( = 0.3) from a monoclinic fergusonite structure to a tetragonal scheelite structure (T), which decreased in temperature as a function of according to thermal expansion analysis. Optimum microwave dielectric performance was obtained for CNV0.3 with permittivity (ε) of ∼16.81, microwave quality factor () of ∼41 300 GHz (at ∼8.7 GHz), and temperature coefficient of the resonant frequency (TCF) of ∼ -3.5 ppm/°C. ε is dominated by Ce-O phonon absorption in the microwave band; is mainly determined by the porosity, grain size, and proximity of T; and TCF is controlled by the structural distortions associated with T. Terahertz (THz) (0.20-2.00 THz, ε ∼ 12.52 ± 0.70, and tan δ ∼ 0.39 ± 0.17) and infrared measurements are consistent, demonstrating that CNV (0.0 ≤ ≤ 0.4) ceramics are effective in the sub-millimeter as well as MW regime. A cylindrical DRA prototype antenna fabricated from CNV0.3 resonated at 7.02 GHz (|| = -28.8 dB), matching simulations, with >90% radiation efficiency and 3.34-5.93 dB gain.
制备了钒（V）取代的铈铌酸盐[Ce(NbV)O，CNV]陶瓷，以探索其结构与微波（MW）性能的关系以及在C波段介质谐振器天线（DRA）中的应用。X射线衍射和拉曼光谱表明，CNV（0.0≤≤0.4）陶瓷在V的临界含量（=0.3）处表现出从单斜氟铈矿结构到四方白钨矿结构（T）的铁弹性相变，根据热膨胀分析，其温度随的增加而降低。对于CNV0.3，获得了最佳的微波介电性能，其介电常数（ε）约为16.81，微波品质因数（）约为41 300 GHz（在约8.7 GHz），谐振频率温度系数（TCF）约为-3.5 ppm/°C。ε由微波波段中的Ce-O声子吸收主导；主要由孔隙率、晶粒尺寸和T的接近程度决定；TCF由与T相关的结构畸变控制。太赫兹（THz）（0.20 - 2.00 THz，ε约为12.52±0.70，tan δ约为0.39±0.17）和红外测量结果一致，表明CNV（0.0≤≤0.4）陶瓷在亚毫米以及MW波段都是有效的。由CNV0.3制成的圆柱形DRA原型天线在7.02 GHz处谐振（|| = -28.8 dB），与模拟结果匹配，辐射效率>90%，增益为3.34 - 5.93 dB。
