悬臂梁式硅微加速度计的研制

介绍一种悬臂梁式硅微加速度计的结构与工作原理,并利用ANSYS软件进行了仿真模拟。采用体硅“无掩膜”腐蚀技术,对设计出的敏感芯片进行了工艺试制。通过合理的设计,使挠性梁腐蚀区域侧面上产生(311)面,通过控制所产生的(311)面对(111)面的侵削作用,获得了所需结构。为提高灵敏度和线性,该加速度计采用静电力反馈闭环控制方式,检测与处理电路采用高精度双极线性电路工艺进行了工艺流片。利用多芯片组装工艺进行了敏感芯片与一次集成的检测和处理电路的混合封装。经测试硅微加速度计性能为量程±50g,分辨率3×10–3g,非线性<5×10–4,质量为9.6g。

Develop of Cantalever Micro-silicon Accelerometer

The structure and principle of cantalever micro-silicon accelerometer was presented. The performance of this accelerometer was simulated with ansys software. The sensitivity chip of accelerometer was fabricated using “maskless” ecting. Though properly design, a (311) sidewall appears in beam etching area , which will invade (111) sidewall. Then needed structure was attained. To improve sensitivity and linearity, feedback loop was adopted with electrostatic in detection and managing circuit, which is fabricated with high precision bipolar linear circuit technology. The sensor and IC chip of accelerometer was packaged using MCM technology. Its performance is measured resolution of 3×10–3g with a full scale of ±50 g, nonlinearity less than 5×10–4, weight as low as 9.6 g.