Pump it up

We report on the use of zipping actuation applied to dielectric elastomer actuators to microfabricate mm-sized pumps. The zipping actuators presented here use electrostatic attraction to deform an elastomeric membrane by pulling it into contact with a rigid counter electrode. We present several actuation schemes using either conventional DEA actuation, zipping, or a combination of both in order to realize microfluidic devices. A zipping design in which the electric field is applied across the elastomer membrane was explored theoretically and experimentally. Single zipping chambers and a micropump body made of a three chambers connected by an embedded channel were wet-etched into a silicon wafer and subsequently covered by a gold-implanted silicone membrane. We measured static deflections of up to 300µm on chambers with square openings of 1.8 and 2.6 mm side, in very good agreement with our model.