A circular microchannel integrated with embedded sprial electrodes used for fluid transportation

This paper proposes a novel method to fabricate a circular microchannel with embedded spiral electrodes used for fluid transportation by inserting glass capillary as sacrificial mould. Utilizing a rolling exposure technique in the photolithography process, the continuous spiral electrode has been formed on the non-planar surface of a glass capillary successfully. Moreover, using the concept of sacrificial layer, the spiral electrodes are transferred on the inner surface of a SU-8 circular microchannel with a diameter of 350 μm. The fabricated device was regarded as an electrohydrodynamic (EHD) micropump, and has a pumping capacity of 4.5 μl/min herein.