一种用于MEMS加速度计温度性能提升的双质量全差分结构

Dual Mass and Fully Differential Structure for Improving Temperature Performance of MEMS Accelerometers

微电子机械系统(MEMS)加速度计作为应力敏感器件,很容易受到外界应力的影响,尤其是对温度应力非常敏感,MEMS加速度计的温度性能成为了制约加速度计性能提升的关键因素。为了提高MEMS加速度计的温度性能,减小温度漂移,提出了一种新型的双质量、全差分MEMS敏感结构方案。通过双质量的差分效果,可以将外界温度变化引起的变形差分掉,从而降低加速度计的温度系数,提高温度性能。利用有限元仿真的手段,优化双质量结构的布局,验证加速度计的温度漂移结果。实验结果表明,加速度计温度性能得到了有效提升。

As a stress sensitive device,micro-electromechanical system(MEMS)accelerometers are easily affected by external stress,especially sensitive to temperature stress.The temperature performance of MEMS accelerometers has become a key factor restricting the improvement of accelerometer performance.In order to improve the temperature performance of MEMS accelerometers and reduce temperature drift,a new dual mass and fully differential MEMS sensitive structure scheme was proposed.Through the differential effect of the dual mass,the deformation caused by external temperature changes could be differentiated,thereby reducing the temperature coefficient of the accelerometer and improving temperature performance.By means of finite element simulation,the dual mass structure layout was optimized and the temperature drift results of the accelerometer were verified.The experimental results show that the temperature performance of the accelerometer is improved effectively.