Rzhanov Institute of Semiconductor Physics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.
Sensors (Basel). 2022 Mar 23;22(7):2460. doi: 10.3390/s22072460.
Silicon-on-insulator (SOI) nanowire or nanoribbon field-effect transistor (FET) biosensors are versatile platforms of electronic detectors for the real-time, label-free, and highly sensitive detection of a wide range of bioparticles. At a low analyte concentration in samples, the target particle diffusion transport to sensor elements is one of the main limitations in their detection. The dielectrophoretic (DEP) manipulation of bioparticles is one of the most successful techniques to overcome this limitation. In this study, TCAD modeling was used to analyze the distribution of the gradient of the electric fields E for the SOI-FET sensors with embedded DEP electrodes to optimize the conditions of the dielectrophoretic delivery of the analyte. Cases with asymmetrical and symmetrical rectangular electrodes with different heights, widths, and distances to the sensor, and with different sensor operation modes were considered. The results showed that the grad factor, which determines the DEP force and affects the bioparticle movement, strongly depended on the position of the DEP electrodes and the sensor operation point. The sensor operation point allows one to change the bioparticle movement direction and, as a result, change the efficiency of the delivery of the target particles to the sensor.
绝缘体上硅（SOI）纳米线或纳米带场效应晶体管（FET）生物传感器是用于实时、无标记和高灵敏度检测广泛生物粒子的电子探测器的多功能平台。在样品中分析物浓度较低的情况下，目标粒子向传感器元件的扩散传输是其检测的主要限制因素之一。介电泳（DEP）操纵生物粒子是克服这一限制的最成功技术之一。在这项研究中，使用 TCAD 建模来分析具有嵌入式 DEP 电极的 SOI-FET 传感器中电场 E 的梯度分布，以优化分析物的介电泳传递条件。考虑了具有不同高度、宽度和与传感器距离的不对称和对称矩形电极以及不同传感器工作模式的情况。结果表明，梯度因子决定介电泳力并影响生物粒子的运动，强烈依赖于 DEP 电极的位置和传感器的工作点。传感器的工作点可以改变生物粒子的运动方向，从而改变目标粒子向传感器的输送效率。
