基于自解耦三明治结构的横向运动栅场效应晶体管MEMS微力传感器

A MEMS Sensors Based on A Laterally Movable Gate Field-Effect Transistor(LMGFET)with A Novel Decoupling Sandwich Structure

本文介绍了一种基于横向可移动栅极场效应晶体管(LMGFET)的新型微型力传感器的开发。提出了一种精确的电气模型,用于小型LMGFET器件的性能评估,与以前的模型相比,其精度有所提高。采用了一种新型三明治结构,该结构由一个金交叉解耦栅阵列层和两个软光阻层SU-8组成。通过所提出的双差分传感结构,LMGFET横向工作在垂直干扰下的输出电流被大大消除,所提出传感器的相对输出误差从4.53%(传统差分结构)降低到0.01%。提出了一种实用的传感器制造工艺,并对其进行了模拟。基于LMGFET的力传感器的灵敏度为4.65μA·nN^(-1),可与垂直可移动栅极场效应晶体管(VMGFET)器件相媲美,但非线性度提高了0.78%,测量范围扩大了±5.10μN。这些分析为LMGFET器件的电气和结构参数提供了全面的设计优化,并证明了所提出的传感器在生物医学显微操作应用中具有良好的力传感潜力。

This paper presents the development of a novel micro force sensor based on a laterally movable gate field-effect transistor(LMGFET).A precise electrical model is proposed for the performance evaluation of small-scale LMGFET devices and exhibits improved accuracy in comparison with previous models.A novel sandwich structure consisting of a gold cross-axis decoupling gate array layer and two soft photoresistive SU-8 layers is utilized.With the proposed dual-differential sensing configuration,the output current of the LMGFET lateral operation under vertical interference is largely eliminated,and the relative output error of the proposed sensor decreases from 4.53%(traditional differential configuration)to 0.01%.A practicable fabrication process is also developed and simulated for the proposed sensor.The proposed LMGFET-based force sensor exhibits a sensitivity of 4.65μA·nN^(-1),which is comparable with vertically movable gate field-effect transistor(VMGFET)devices,but has an improved nonlinearity of 0.78% and a larger measurement range of±5.10 lN.These analyses provide a comprehensive design optimization of the electrical and structural parameters of LMGFET devices and demonstrate the proposed sensor’s excellent force-sensing potential for biomedical micromanipulation applications.