基于MEMS的高灵敏度电容式低频传声器

Research on Condenser High Sensitivity Low-frequency Microphone Based on MEMS

在硅微电容式传声器相关理论及前人对方形膜的研究的基础上,提出了一种用于测试低频信号的电容式高灵敏度圆形硅微振动膜传声器。模拟仿真和结构参数优化,为实践提供了理论依据。在此基础上,探索性的研制了圆形振动膜半径为40mm,气隙厚度为50μm的低频传声器,实验表明,该传声器具有较高的灵敏度,当偏置电压为6V、100Hz时,灵敏度高达-25dB,在通频带(20～800Hz)局部平坦。

This paper presents the research on the condenser high sensitivity low-frequency circular silicon diaphragm microphone based on MEMS technology with the help of other＇s work and relative theory. Simulation and structure parameter optimization supplies the theory basis for practice. On this base, a condenser low-frequency microphone with a air gap of 50 μm and a radius of 40 mm of circular silicon diaphragm is exploringly developed. Experimental result shows that this microphone has high sensitivity of -25 dB at 100 Hz and is locally flat in the transmission bands （20-800 Hz） at the bias voltage of 6 V.