Wang Haoran, Ma Yifei, Zheng Qincheng, Cao Ke, Lu Yao, Xie Huikai
Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611, USA.
School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China.
Micromachines (Basel). 2021 Oct 16;12(10):1257. doi: 10.3390/mi12101257.
Facilitated by microelectromechanical systems (MEMS) technology, MEMS speakers or microspeakers have been rapidly developed during the past decade to meet the requirements of the flourishing audio market. With advantages of a small footprint, low cost, and easy assembly, MEMS speakers are drawing extensive attention for potential applications in hearing instruments, portable electronics, and the Internet of Things (IoT). MEMS speakers based on different transduction mechanisms, including piezoelectric, electrodynamic, electrostatic, and thermoacoustic actuation, have been developed and significant progresses have been made in commercialization in the last few years. In this article, the principle and modeling of each MEMS speaker type is briefly introduced first. Then, the development of MEMS speakers is reviewed with key specifications of state-of-the-art MEMS speakers summarized. The advantages and challenges of all four types of MEMS speakers are compared and discussed. New approaches to improve sound pressure levels (SPLs) of MEMS speakers are also proposed. Finally, the remaining challenges and outlook of MEMS speakers are given.
在微机电系统（MEMS）技术的推动下，MEMS扬声器或微型扬声器在过去十年中得到了迅速发展，以满足蓬勃发展的音频市场的需求。由于具有占地面积小、成本低和易于组装的优点，MEMS扬声器在听力仪器、便携式电子产品和物联网（IoT）的潜在应用中受到了广泛关注。基于不同转换机制（包括压电、电动、静电和热声驱动）的MEMS扬声器已经得到开发，并且在过去几年的商业化方面取得了重大进展。在本文中，首先简要介绍了每种MEMS扬声器类型的原理和建模。然后，回顾了MEMS扬声器的发展，并总结了最先进的MEMS扬声器的关键规格。比较并讨论了所有四种类型MEMS扬声器的优点和挑战。还提出了提高MEMS扬声器声压级（SPL）的新方法。最后，给出了MEMS扬声器面临的剩余挑战和前景。
