Varadharajan Idhaiam Kavin Sivaneri, Caswell Joshua A, Pozo Peter D, Sabolsky Katarzyna, Sierros Konstantinos A, Reynolds Daryl S, Sabolsky Edward M
Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506, USA.
Lane Department of Computer Science and Electrical Engineering, West Virginia University, Morgantown, WV 26506, USA.
Sensors (Basel). 2022 Mar 10;22(6):2165. doi: 10.3390/s22062165.
In this work, an all-ceramic passive wireless inductor-capacitor (LC) resonator was presented for stable temperature sensing up to 1200 °C in air. Instead of using conventional metallic electrodes, the LC resonators are modeled and fabricated with thermally stable and highly electroconductive ceramic oxide. The LC resonator was modeled in ANSYS HFSS to operate in a low-frequency region (50 MHz) within 50 × 50 mm geometry using the actual material properties of the circuit elements. The LC resonator was composed of a parallel plate capacitor coupled with a planar inductor deposited on an AlO substrate using screen-printing, and the ceramic pattern was sintered at 1250 °C for 4 h in an ambient atmosphere. The sensitivity (average change in resonant frequency with respect to temperature) from 200-1200 °C was ~170 kHz/°C. The temperature-dependent electrical conductivity of the tin-doped indium oxide (ITO, 10% SnO doping) on the quality factor showed an increase of from 36 to 43 between 200 °C and 1200 °C. The proposed ITO electrodes displayed improved sensitivity and quality factor at elevated temperatures, proving them to be an excellent candidate for temperature sensing in harsh environments. The microstructural analysis of the co-sintered LC resonator was performed using a scanning electron microscope (SEM) which showed that there are no cross-sectional and topographical defects after several thermal treatments.
在这项工作中，提出了一种全陶瓷无源无线电感 - 电容（LC）谐振器，用于在空气中稳定地进行高达1200°C的温度传感。该LC谐振器并非使用传统的金属电极，而是采用热稳定且高导电的陶瓷氧化物进行建模和制造。利用电路元件的实际材料特性，在ANSYS HFSS中对LC谐振器进行建模，使其在50×50 mm几何尺寸内的低频区域（50 MHz）工作。该LC谐振器由一个平行板电容器与一个通过丝网印刷沉积在AlO基板上的平面电感器耦合而成，陶瓷图案在环境气氛中于1250°C烧结4小时。200 - 1200°C范围内的灵敏度（谐振频率随温度的平均变化）约为170 kHz/°C。掺杂10% SnO的氧化铟锡（ITO）的温度依赖性电导率对品质因数的影响表明，在200°C至1200°C之间，品质因数从36增加到43。所提出的ITO电极在高温下表现出更高的灵敏度和品质因数，证明它们是恶劣环境中温度传感的极佳候选材料。使用扫描电子显微镜（SEM）对共烧结的LC谐振器进行微观结构分析，结果表明经过多次热处理后，没有横截面和形貌缺陷。
