电容式硅基MEMS传声器的结构优化设计  

Structure Optimization Design for the Capacitive Silicon-Based MEMS Microphone

作　　者：沈国豪 张卫平 刘武 魏志方 邹逸飞 Shen Guohao;Zhaing Weiping;Liu Wu;Wei Zhifang;Zou Yifei(National Key Laboratory of Science and Technology on Micro/Nano Fabrication,Shanghai 200240,China;Department of Micro/Nano Electronics,School of Electronic Information and Electrical Engineering,.Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]微米/纳米加工技术国家级重点实验室,上海200240 [2]上海交通大学电子信息与电气工程学院微纳电子学系,上海200240

出　　处：《半导体技术》2018年第12期912-917,共6页Semiconductor Technology

摘　　要：微电子机械系统(MEMS)传声器是一种将音频信号转换为电信号的微型传感器。为了得到较高灵敏度和信噪比(SNR)的传声器,同时又能保证其可靠性,设计并制备了一种结构优化的电容式硅基MEMS传声器。将两种特殊结构相结合,对电容式硅基MEMS传声器的带孔振动膜结构进行了优化。振动膜采用厚度各异的掺杂多晶硅-非掺杂多晶硅-掺杂多晶硅的特殊膜结构以得到低应力振动膜。采用特殊的防粘连结构以防止为了提高灵敏度可能带来的粘连现象。结构优化后的MEMS传声器分别采用顶部封装和底部封装两种方式进行封装,对实验样品进行测试,结果显示其灵敏度约为-41 dB,信噪比约为64 dB,参数值均符合市场行业标准,此MEMS传声器结构具有可行性。The micro-electromechanical system( MEMS) microphone is the miniature sensor converting the sound signal into the electrical signal. In order to obtain the microphone with higher sensitivity and signal to noise ratio( SNR),a capacitive silicon-based MEMS microphone was designed and fabricated,and its reliability can be ensured. Two special structures were combined to optimize the perforated structure of vibrating membrane of the capacitive silicon-based MEMS microphone. The special structure of the vibrating membrane( different thicknesses of doped poly-Si/undoped poly-Si/doped poly-Si) was used to obtain the low-stress membrane. The special anti-blocking structure was used to prevent adhesions caused by the increase of the sensitivity. The structure-optimized capacitive silicon-based MEMS microphone was packaged in two different ways,such as the top package and the bottom package. The packaged samples were tested,and the results show that the sensitivity of the samples is about-41 d B,and the SNR of the samples is about 64 dB. These parameters are in line with the market industry standards.Therefore,the structure of the MEMS microphone is feasible.

关 键 词：微电子机械系统(MEMS)器件 电容式传声器 低应力振动膜 防粘连结构 顶(底)端开口封装 

分 类 号：TN304.12[电子电信—物理电子学] TN641.2