微惯性器件的稳定性控制方法研究

The high stability of micro inertial sensors is needed in Aeronautics & Astronautics fields,its stability is one of the current research hotpots and difficulties.The residual stress is key factor to affect the stability of micro inertial sensors, lack of systematic research in this field. In the project, all silicon sandwich structure capacitive accelerometer developed as the prototype, considering the charge state of sensing capacitor electrode interface, effect of doping properties of silicon wafer on its stability is studied by establishment of electromechanical coupling model of the sensor and close-loop feedback interface circuits system model. Low stress silicon/silicon bonding process is studied to reduce the effect of residual stress introduced in bonding process. Considering the design of spring beam anchor realeasing stress, effects of different elastic beam structure, parameters, release method on stress is studied to present principles on low stress design. The research will breakthrough the key base technology of design, fabrication, packaging and testing of high stability micro accelerometer and provide strong technical base for the sensor applied in inertial navigation/guidance field.

航空航天等领域对微惯性传感器的稳定性有很高的要求，其稳定性问题是当前研究的热点和难点之一。残余应力是影响微惯性传感器稳定性的关键因素，在该方面缺少深入系统性的研究。本项目以前期研制的全硅三明治结构电容式微加速度计为样机，通过建立考虑敏感电容电极界面电荷状态的传感器机电耦合模型及闭环反馈接口电路系统模型，研究硅片的搀杂特性(p型或n型)对其稳定性的影响；研究低应力硅硅键合工艺，降低键合引入的残余应力影响；结合可释放应力的弹性梁锚点设计,研究传感器不同弹性梁结构、参数、释放方法对应力大小的影响，给出低应力设计的基本准则。项目的研究将突破高稳定性微加速度计在设计、制造、封装和检测等方面的关键基础技术，为其在惯性导航等领域应用打下深厚的基础。

航空航天等领域对微惯性传感器的稳定性有很高的要求，其稳定性问题是当前研究的热点和难点之一，残余应力是影响微惯性传感器稳定性的关键因素。本项目建立了微加速度计闭环反馈接口电路系统模型，分析了界面因素对闭环反馈稳定性的影响。微加速度传感器通过采用低应力双面对称折叠弹性梁结构、低温释放工艺、低应力键合工艺、单硅片制作、优化真空封装工艺参数等技术手段，降低了残余应力对传感器稳定性的影响。项目的开展突破了高稳定性微加速度计在设计、制造、封装和检测等方面的关键基础技术，研制的加速度传感器模块量程2g,非线性-0.63%,带宽200Hz，动态范围120dB，温度系数仅为0.11mg/C，零位稳定性（Allan方差）6.54ppm。发表论文3篇，其中SCI论文2篇，授权发明专利 3项，其中美国专利2项。培养博士研究生1名，硕士研究生2名。