压阻式硅微二维加速度计的加工与测试

提出了一种压阻式的硅微二维加速度计，该加速度计采用4个相互垂直的悬臂梁支撑中间有刚硬柱体的结构，利用合理布置的压敏电阻构成的惠斯通电桥测量水平面内两个方向的加速度．结合微结构的力学分析模型以及压阻原理分析了加速度计的灵敏特性、采用硅微机械加工工艺完成了加速度计的加工，应用微系统分析仪、激光拉曼光谱应力测试仪以及振动台分别对加工出的微结构形貌、残余应力、频响以及灵敏特性进行了相关测试．测试结果表明，两个方向的输出值均灵敏度高、线形度较好，胸灵敏度为1、0174mV／g（g为重力加速度），线性系数为0．99991，y向灵敏度为0．89761mV／g，线性系数为0．99945．微加速度计的频响曲线较为平坦，其共振频率大约为670Hz．

Fabrication and Testing of a Silicon-Based Piezoresistive Two-Axis Accelerometer

A novel two-axis accelerometer was presented in this paper, which is based on piezoresistive detection.This kind of sensor consists of four vertical cantilever beams with attached cylinder in the center of the sturcture. By locating the resis- tor logically to form the Wheatstone birdge, this sensor can measure the acceleration in two directions. The characteristic of structure＇s sensitivity was analyzed by the mechanical model and piezoresistive effect. The accelerometer was fabricated on silicon using MEMS technology, and the geometry dimension, residual stress, frequency response and sensitivity were re- spectively tested by means of microsystem analyzer, laser Raman spectroscopy quantitate-stress system and vibrating table. The experimental results show that the accelerometer has high sensitivity and good linearity in two directions.The sensitivity of the X direction and Y direction is 1.017 4 mV/g and 0.897 61 mV/g, respectively, the linearity of the X direction and Y direction is 0.999 91 and 0.999 45, respectively. The curve of frequency response is straight and smooth,and the measured resonance frequency is about 670 Hz.