基于钎焊的MEMS陀螺真空封装设计与实验研究

对于线振动硅微机电系统(MEMS)陀螺,真空封装是减小其振动阻尼、提高振动品质因数,进而提高性能的一种有效的措施。设计了一种基于钎焊的硅MEMS陀螺真空封装方案,该方案因不采用吸气剂,故可实现真空度可控。理论计算表明:该封装形式可以保持1 Pa以下的真空度;经过对真空封装后的陀螺实验测试结果表明:设计的陀螺驱动轴品质因数为1500,实际封装后的陀螺驱动轴品质因数为1700,满足真空度设计目标。经过对封装后的陀螺品质因数进行186 d的跟踪测试,品质因数基本保持不变,验证了该真空封装方案的可靠性。

Design and experimental research on vacuum packaging of MEMS gyroscope based on braze welding

Vacuum package is an effective method to reduce the vibration damping,and improve the quality factor,and to improve the performance of silicon MEMS linear vibratory gyroscopes.A design proposal of vacuum packaging of gyroscopes based on braze welding is introduced.The proposal is executed without using any getter,so the controllable vacuum degree can be realized.Theoretical calculation shows that,this packaging can maintain vacuum degree below 1Pa.The test on vacuum packaged gyroscope shows that the Q factor of gyroscope’s driving mode is 1700,which meets the design goals of 1500.After test for 186d,the gyro’s Q factor remains unchanged,which verifies the reliability of this vacuum packaging scheme.