四电极电化学MEMS加速度传感器仿真

基于溶液相对于电极的运动会使电极附近因电势差作用而产生的离子浓度梯度发生改变,从而使电极电流发生变化等电化学原理,建立一种置于碘(I2)和碘化钾(KI)混合水溶液环境中的阳极—阴极—阴极—阳极(ACCA)四电极阵列传感单元模型。通过理论分析,该传感单元可以局部电解液为惯性质量,利用电解液中带电离子相对于电极的运动来产生并输出附加电流;进一步的建模仿真证明:在一定的加速度范围内(0a x0.149 m/s2),附加电流的大小同加速度呈正比关系,故可以将此电流放大输出,从而实现对加速度大小的表征。可利用MEMS工艺制作,并封装此传感单元成为加速度传感器。

Simulation of four-electrode electrochemical MEMS acceleration sensor

A sensing unit model with an anode-cathode-cathode-anode （ACCA） four-electrode array placed in mixed solution environment of KI and 12 is established based on electrochemical principle that a changing ion concentration gradient of the electrolyte resulting from the relative motion of electrolyte and electrodes can change electrode currents. Through theoretical analysis, additional current can be produced by the sensing cell based on relative motion of partial electrolyte （liquid inertial mass） and electrodes. This additional current is proportional to acceleration （0 〈ax 〈0. 149 m/s2 ） indicated by further modeling and simulation and thus can be output after amplifying to characterize the acceleration. The process of MEMS can be used to fabricate and package the sensing unit into acceleration sensor.