Javadi Elham, But Dmytro B, Ikamas Kęstutis, Zdanevičius Justinas, Knap Wojciech, Lisauskas Alvydas
CENTERA Laboratories, Institute of High Pressure Physics PAS, 01-142 Warsaw, Poland.
CEZAMAT, Warsaw Technical University, 02-822 Warsaw, Poland.
Sensors (Basel). 2021 Apr 21;21(9):2909. doi: 10.3390/s21092909.
This paper presents an overview of the different methods used for sensitivity (i.e., responsivity and noise equivalent power) determination of state-of-the-art field-effect transistor-based THz detectors/sensors. We point out that the reported result may depend very much on the method used to determine the effective area of the sensor, often leading to discrepancies of up to orders of magnitude. The challenges that arise when selecting a proper method for characterisation are demonstrated using the example of a 2×7 detector array. This array utilises field-effect transistors and monolithically integrated patch antennas at 620 GHz. The directivities of the individual antennas were simulated and determined from the measured angle dependence of the rectified voltage, as a function of tilting in the E- and H-planes. Furthermore, this study shows that the experimentally determined directivity and simulations imply that the part of radiation might still propagate in the substrate, resulting in modification of the sensor effective area. Our work summarises the methods for determining sensitivity which are paving the way towards the unified scientific metrology of FET-based THz sensors, which is important for both researchers competing for records, potential users, and system designers.
本文概述了用于确定基于场效应晶体管的最新太赫兹探测器/传感器灵敏度（即响应度和噪声等效功率）的不同方法。我们指出，报告的结果可能在很大程度上取决于用于确定传感器有效面积的方法，这常常导致数量级高达几个数量级的差异。以一个2×7探测器阵列为例，展示了选择合适的表征方法时所面临的挑战。该阵列在620 GHz频率下利用场效应晶体管和单片集成贴片天线。通过测量整流电压随在E平面和H平面倾斜的角度依赖性，模拟并确定了各个天线的方向图。此外，本研究表明，实验确定的方向图和模拟结果表明，部分辐射可能仍在衬底中传播，从而导致传感器有效面积发生变化。我们的工作总结了确定灵敏度的方法，这些方法为基于场效应晶体管的太赫兹传感器的统一科学计量学铺平了道路，这对争夺记录的研究人员、潜在用户和系统设计师都很重要。
