Micro bubble removal from micro pattern structure under alternating electric field

Various sizes of concave square patterns are used for micro bubble adhesion and removal investigation in a water/methanol mixture solution. As decreasing the surface energy of the solution, the micro bubble is more likely to remove from the square patterns. However, the micro bubble is less likely to remove as decreasing the square size of patterns. The threshold concentration of water/methanol solution for bubble removal can be determined. Based on the surface energy analysis, the adhesion and removal mechanisms of micro bubble can be explained. By applying alternating electric field to an isolated bubble, electric decomposition of water occurred at the electrode surface. The possibility of removal control of micro bubble is discussed.