一种新结构硅微机械压阻加速度计  

A New Structure Silicon Piezoresistive Micromachined Accelerometer

作　　者：陈雪萌[1] 李昕欣[1] 宋朝晖[1] 王跃林[1] 黄晖[1] 黄树森[1] 张鲲[1] 

机构地区：[1]中国科学院上海微系统与信息技术研究所传感技术国家重点实验室,上海200050

出　　处：《传感技术学报》2005年第3期500-503,共4页Chinese Journal of Sensors and Actuators

摘　　要：设计、制造并测试了一种新结构硅微机械压阻加速度计。器件结构是悬臂梁-质量块结构的一种变形。比较硬的主悬臂梁提供了一定的机械强度,并且提供了高谐振频率。微梁很细,检测时微梁沿轴向直拉直压。力敏电阻就扩散在微梁上,质量块很小的挠动就能在微梁上产生很大的应力,输出很大的信号。5 V条件下,灵敏度为14.80 mV/g,谐振频率为994Hz,分别是传统结构压阻加速度计的2.487倍和2.485倍。加速度计用普通的N型硅片制造,为了刻蚀高深宽比的结构,使用了深反应离子刻蚀(DRIE)工艺。A new structure silicon piezoresistive micromachined accelerometer has been designed, fabricated and tested. The device structure is a variation of conventional cantilever-mass structure. The main cantilever, which is rigid, provides high mechanical rigidity and high resonance frequency. The micro beams are slim and they will elongate or shorten axially when the accelerometer is tested. The piezoresistors are diffused on micro beams so that very large stress occurs when the proof mass moves slightly. Under 5 V dc supply, the sensitivity of accelerometer is 14. 80 mV/g and resonance frequency is as high as 994 Hz,2. 487 and 2. 485 times equivalent to the specifications of a typical conventional cantilever-mass piezoresistive accelerometer. This accelerometer is fabricated by N type silicon wafer. To obtain high aspect ratio structure, deep reactive ion etching （DRIE） process is employed.

关 键 词：微机械 加速度计 压阻 深反应离子刻蚀 

分 类 号：TH824.4[机械工程—仪器科学与技术]