新型谐振式硅微机械加速度计  

A Novel Silicon Micromachined Resonant Accelerometer

作　　者：钟莹[1] 张国雄[1] 李醒飞[1] 

机构地区：[1]天津大学精密测试技术与仪器国家重点实验室,天津300072

出　　处：《纳米技术与精密工程》2003年第1期34-37,共4页Nanotechnology and Precision Engineering

基　　金：国家自然科学基金资助项目(50275108)

摘　　要：制作出一种新型结构的谐振式硅微加速度计,其输出频率信号可以克服微机电系统器件输出微弱信号检测的困难.采用双端固定音叉作为谐振器,在加速度作用下,质量块的惯性力通过悬臂梁施加于音叉轴向,利用音叉谐振频率的变化测量加速度.在每个音叉臂上制作了梳齿结构,用梳齿间的静电力激励音叉产生谐振,并利用其构成的电容检测其振动频率.该加速度计采用体硅工艺制作,文中给出了工艺流程.用有限元方法仿真估算,得到传感器的灵敏度约为2/g Hz.This paper proposes a novel silicon micromachined resonant accelerometer. By its quasi-digital output, the trouble in detecting feeble analog signals from most MEMS devices could be averted. In this design, two double-ended tuning forks (DETF) serve as the stress-sensitive resonators. When an external acceleration is applied, the inertial force generated by the proof mass imposes on the fork axially through the cantilever, consequently the shift in the resonant frequency of the fork reflects the acceleration. Electrostatic combs are attached to each tine in order to drive the fork to resonate as a voltage is applied, and the capacitance between the fixed and movable combs is used to sense the resonant frequency. This sensor is fabricated by bulk-micromach-ining, and the process is presented. Finite element analysis software is used to simulate the performance of the sensor. As a result, the scale factor is estimated to be 2/g Hz.

关 键 词：谐振器 加速度测量 力学量传感器 硅微机械加工 加速度计 结构设计 仿真估算 体硅工艺 

分 类 号：TH824.4[机械工程—仪器科学与技术]