Abstract
The microvalve is one of the most important components in microfluidics. With decades of development, the microvalve has been widely used in many industries such as life science, chemical engineering, chip, and so forth. This paper presents a comprehensive review of the progress made over the past years about microvalves based on different actuation mechanisms. According to driving sources, plenty of actuation mechanisms are developed and adopted in microvalves, including electricity, magnetism, gas, material and creature, surface acoustic wave, and so on. Although there are currently a variety of microvalves, problems such as leakage, low precision, poor reliability, high energy consumption, and high cost still exist. Problems deserving to be further addressed are suggested, aimed at materials, fabrication methods, controlling performances, flow characteristics, and applications.