Studies Based On One-plane System Of Electrowetting On Dielectric (EWOD)

In recent years, the microelectromechanical systems (MEMS) technology has a rapid development. The devices become smaller and smaller, and more and more people start to research the micro-fluidic system. Electrowetting becomes a research focus as a method of manipulation of droplets in the micro-fluidic system. It has several advantages:such as simple fabrication, easy droplet volume controlling, easy mixing, and low cost.In section one, the basic physical phenomena of electrowetting have been discussed. The physical and mathematical model of the wetting and electrowetting has been proposed. The surface tension, the Laplace equation, the Young equation and the Lippmann-Young equation are summarized. And the electrowetting phenomenon has been analyzed basic on the thermodynamic model and the electromechanical model. The actuation of droplet in the Electrowetting-on-dielectric (EWOD) devices has been described from the macroscopic droplet movement. The relationship between the actuation of droplet and the various forces has been studied. In addition, the movement of droplet from microscopic point is mentioned.In section two, the experiment of the open-EWOD device has been designed. The shape of electrodes has three types:round, square and strip. The size and distance of the electrodes are different. The connection between the electrodes has two types. The movement of droplets, including the transport and coalescence under the different voltage and frequency has been studied. In addition, some experiments on the vibration of the droplet under the AC voltage and breakdown of the dielectric layer have been studied.