Zhou Wu, He Jiangbo, Yu Huijun, Peng Bei, He Xiaoping
School of Mechanical and Electrical Engineering, University of Electronic Technology and Science of China, Chengdu 611731, China.
School of Mechanical Engineering, Xihua University, Chengdu 610039, China.
Materials (Basel). 2018 Jan 20;11(1):163. doi: 10.3390/ma11010163.
The glass polarization effects were introduced in this paper to study the main cause of turn-on drift phenomenon of closed-loop micro-accelerometers. The glass substrate underneath the sensitive silicon structure underwent a polarizing process when the DC bias voltage was applied. The slow polarizing process induced an additional electrostatic field to continually drag the movable mass block from one position to another so that the sensing capacitance was changed, which led to an output drift of micro-accelerometers. This drift was indirectly tested by experiments and could be sharply reduced by a shielding layer deposited on the glass substrate because the extra electrical filed was prohibited from generating extra electrostatic forces on the movable fingers of the mass block. The experimental results indicate the average magnitude of drift decreased about 73%, from 3.69 to 0.99 mV. The conclusions proposed in this paper showed a meaningful guideline to improve the stability of micro-devices based on silicon-on-glass structures.
本文引入玻璃极化效应来研究闭环微加速度计开启漂移现象的主要原因。当施加直流偏置电压时，敏感硅结构下方的玻璃衬底会经历极化过程。缓慢的极化过程会感应出一个附加静电场，持续将可动质量块从一个位置拖到另一个位置，从而使传感电容发生变化，导致微加速度计的输出漂移。这种漂移通过实验进行了间接测试，并且可以通过在玻璃衬底上沉积屏蔽层而大幅降低，因为额外电场被阻止在质量块的可动指上产生额外静电力。实验结果表明，漂移的平均幅度从3.69 mV降至0.99 mV，下降了约73%。本文提出的结论为提高基于玻璃上硅结构的微器件稳定性提供了有意义的指导方针。
