HEMT高灵敏度微加速度计的设计与测试

Design and Testing on High Sensitive Micro-accelerometer Based on HEMT

根据压阻传感原理设计了GaN/AlGaN高电子迁移率晶体管(high electron mobility transistor,HEMT)器件与Si基悬臂梁-质量块结构集成的微加速度。通过ANSYS结构应力仿真,GaN基HEMT作为敏感单元置于微悬臂梁结构根部的应力最大处。同时对微加速度计的关键研制工艺进行了设计和研究,成功制备出具有力电耦合特性的传感结构。并且测试了微结构在静态0～10g的惯性测试,结果表明GaN基HEMT器件具备明显的力电耦合效应,该微加速度计的灵敏度为0.24 mA/g,线性度为12.4%,适合研制高灵敏度的微加速度计。

The micro-accelerometer integrated by GaN/AlGaN HEMT device and Si cantilever-mass structure was designed according to piezoresistive sensing principle.Through simulating the distribution of stress on structure by ANSYS software,the GaN HEMT were located at maximum stress point near the root of the cantilevers as sensitive cells.The sensing structure possessed electromechanical coupling characteristics was fabricated successfully by designing and researching the key process of manufacturing the micro-accelerometer.The results of static inertial testing in the range from 0 to 10 g indicate that the HEMT based on GaN device has obvious electromechanical coupling effect.And the sensivity and linearity of the micro-accelerometer achieve 0.24 mA/g and 12.4% respectively,which is of great significance for the development of the sensitive micro-accelerometer.