MEMS电容应变传感器

MEMS capacitive strain sensor

本文详细介绍了一种用硅玻璃键合工艺制作的微型梁式电容应变传感器,通过ANSYS软件并结合MEMS器件的特点进行优化,设计并制作了由MEMS工艺实现的微型梁式电容应变传感器。为保证应变器件稳定工作,在测量电路中加一直流静电驱动电压在电容器的极板之间,以保证建立的电场在两极之间产生一个静电力,引起膜片发生向下形变的弯曲,从而保证作用在轴向的应力不会使应变梁产生失稳。文中详细给出了工艺流程和测试结果,通过实验测试证明,用这种方法制作的电容应变器件具有良好的线性、较小的滞后和稳定的工作特性,其中应变灵敏度达10fF/MPa,测量误差小于1%FS。

This paper introduces a micro capacitive strain sensor fabricated using silicon-glass static bonding technology. The main fabrication process is given in detail. ANSYS software is used to optimize the design. To sure the stability of the strain sensor, a DC voltage is applied between two electrodes of the capacitor and the established electric field generates a static force, which causes the strain beam to be bended to the substrate so that the stability of the beam can be assured. Sensor test experiments were carried out. Experiment results prove that the proposed strain sensor has excellent linearity, small hysteresis and good stability. The strain sensitivity reaches 10fF/Mpa and the measurement error is less than 1% FS.