石英谐振加速度传感器芯片设计与仿真

Design and Simulation of Quartz Resonant Accelerometer Design and Simulation of Quartz Resonant Accelerometer

分体式石英谐振加速度传感器在性能提升上受到装配误差等因素的影响较大,故提出一种全石英谐振加速度计芯片结构,包括下层的硅结构和上层的石英结构。下层的硅基底仅作为支撑结构进行加工制作,敏感单元为全石英材料,硅结构与石英结构键合到一起,结构加工完成后去除硅材料,以释放石英敏感单元。整体结构为中心对称,包括质量块、音叉结构、微杠杆结构和应力分配梁,芯片通过微杠杆结构来增大传感器的灵敏度,并通过应力分配梁使石英音叉两根振梁上的内应力均匀一致。通过仿真验证了设计的有效性,仿真的差动灵敏度为35Hz/g。

The perfonnance improvement of separated-type quartz resonant accelerometer is greatly affected by factors such as assembly error.In this paper,a new way to fabricate quartz resonant accelerometer is proposed,which includes Silicon substrate of lower layer and quartz sensing structure of upper layer.The Silicon substrate is used as a supporting structure for processing and the quartz structure is a sensitive unit.The Silicon structure and the quartz structure are bonded together.The Silicon material is removed after processing to release the quartz sensitive unit.The overall structure is centersymmetric,including proof mass,tuning fork structure,micro-leverage structure and a link beam.The micro-leverage mechanism amplifies the inertial force to increase the sensitivity of the sensor.The link beam is proposed to concentrate and the internal stress is evenly distributed to the dual beams of DETF.The validity of the design is verified by simulation.The differential sensitivity of the simulation is 35 Hz/g.