微放电是放电通道被限制在一个很小空间区域内的气体放电,电极间隙或放电空间尺度一般为亚毫米以下量级。相比常规尺度放电,放电尺度的减小使得微放电具有很多独特性质,因而受到研究者的日益关注。一方面,微放电结构适合于微型化和平面化,可以应用于生物医学、微区电晕散热技术、微机电驱动系统、离子风机、静电流体加速器、气体传感器、离子源、液相放电加工工艺和漏电检测等诸多方面。另一方面,随着大规模集成电路、微电子工艺和微机电系统的迅速发展,电子元件的集成度越来越高,导体电极本身的尺寸和导体之间的间隙大大降低,小电压可以在微电极间隙产生很强的电场,从而造成低电压击穿,成为微电子产品、火工品和电力系统的安全危害源之一。文章对微放电的研究历史、基本原理、击穿与放电特性、稳定性进行了综述,介绍了电晕微放电、微空心阴极放电、DBD微放电、毛细管放电等不同的微放电结构,并从ESD和安全防护、力学效应、光学效应、电学效应、化学与生物医学效应5个方面对微放电近年来的应用研究进展进行了总结。
Micro-discharge happens in a limited space. The gap spacing has the magnitude of sub-millimeters or below. Compared with the traditional gas discharge, micro-discharge has some unique characteristics due to the micro-scale and hence attracts a great amount of interest. On one hand, the micro-discharge system is easy to be miniaturized thus having great potential in applications such as biomedicine, micro-region thermal cooling, micro-electro-mechanical system, ionic blower, electrostatic-fluid accelerator, gas sensor, ion sources, liquid discharge technic, and electrostatic detection. On the other hand, accompanying with the rapid development of integrated circuits, micro-electronics technology and micro-electro-mechanical systems, the dimension of the conductor electrodes as well as the gap spacing between them has been sharply reduced. A possible risk comes from electrostatic discharge under low voltage breakdown that could turn to a hazard source for micro-electronics, initiate explosive materials or devices as well as electric power system. We review and summarize numerous experimental, computational and analytical works on micro-discharge and micro-plasma in recent years, and introduce progress in understanding the mechanisms and physics of micro-discharge and in the applications.