Development of an Electrohydrodynamic Micropump

An ion-drag pump consisting of microscale electrodes was built. The electrodes were fabricated as a series of planar comb fingers. The electrodes were paired as an emitter and a collector with a 10 mum width and 20 mum gap between them. The number of electrode pairs was 60 and the gap between the electrode pairs was 200 mum. The electrodes were fabricated on a glass plate by the deposition of Cr/Au (500 A/3000 A). The fluid used was HFE-7100 (3M), and all the experiments were conducted inside a class 1000 clean room with controlled moisture content (19.0%) and temperature (295.55 plusmn 0.5 K). The pump generated a maximum pressure of 250 Pa at an applied voltage of 700 V (at an electric field of 35 V/mum). The behavior of the static pressure and the corresponding current during transient state was also observed. The static pressure and the current showed a sharp peak at a high voltage.