Microfabricated all-around-electrode AC electroosmotic pump with simple design and increased velocity generation

AC electroosmosis is a convenient valveless method to pump liquids, whilst avoiding electrolysis and gas generation. Basic designs presented in the literature often have limited velocity or pressure capabilities. This paper reports a simple approach to the design and fabrication of AC electroosmotic (ACEO) micropumps with electrodes that completely surround the channel. We present a fabrication process with two lithographic steps and show that the new prototypes allow for a dramatic increase of the velocity generation - up to 360% compared to devices where electrodes are placed only on one side of the channel.