新型MEMS仿生声敏感芯片设计与晶圆级测试

Design and wafer level test of novel MEMS bionic sound sensitive chip

面向生产线设备智能故障诊断与维护预测对低频、低成本麦克风的应用需求,针对现有微机电系统(MEMS)声传感器低频响应差、高频资源浪费和精密测量驻极体麦克风成本高的问题,通过分析奥米亚寄生蝇的听觉器官的工作原理,提出了一种具有抗振动干扰功能的单支点差分结构MEMS仿生麦克风芯片,制定了晶圆级封装加工流程。建立了有限元仿真模型,仿真分析结果表明:设计的MEMS仿生麦克风芯片的一阶谐振频率为3.92 kHz,可以满足低频声波探测的应用需求。声波灵敏度为3.04 fF/Pa,振动灵敏度为2.1×10^(-4)fF/gn,可以实现抗振动干扰的目的。在6 in MEMS加工平台上完成了6 in晶圆的加工与晶圆测试。测试结果表明,所设计加工的MEMS仿生声敏感芯片电容的一致性比较好。

In order to meet the application requirements of low frequency and low cost microphones for intelligent fault diagnosis and maintenance prediction of production line equipment,and to solve the problems of poor low frequency response and waste of high frequency resources of existing MEMS acoustic sensors,and high cost of precision measurement electret cindenser microphone(ECM),a single support differential structure MEMS bionic microphone chip with anti-vibration interference function is proposed by analyzing the working principle of the auditory organ of the Ormia ochracea,and a wafer level packaging process flow is formulated.The finite element simulation model is established.The simulation analysis results show that the first-order resonant frequency of the designed MEMS bionic microphone chip is 3.92 kHz,which can meet the application requirements of low-frequency acoustic wave detection.The acoustic wave sensitivity is 3.04 fF/Pa,and the vibration sensitivity is 2.1×10^(-4)fF/gn,which can achieve the purpose of anti-vibration interference.The processing and testing of 6-inch wafers are completed on 6-inch MEMS processing platform.The test results indicate that the consistency of the designed and processed MEMS biomimetic sound sensitive chip capacitors is relatively good.