Proposal of a peristaltic micropump using dielectric elastomer actuators fabricated by MEMS technology

Abstract

A peristaltic micropump using dielectric elastomer (DE) actuators is proposed and developed. The peristaltic micropump is designed so that diaphragm-type DE actuators are placed serially on a microchannel and volume changes due to diaphragm-type DE actuators can transfer fluid and pressure. In this report, we propose a novel MEMS process that enables us to place multiple DE actuators on the microchannel. In order to fabricate a DE actuator using a MEMS technology, ultraviolet (UV) curable materials for both compliant electrodes and DE were selected. Poly(3, 4- ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was used for compliant electrodes. PEDOT:PSS is a polymer mixture of two ionomers and a conductive, transparent polymer. As a DE material, polydimethylsiloxane (PDMS) was used. PDMS is a silicon-based organic polymer and is widely used for the DE. In this research, both PEDOT:PSS and DE modified to have an UV curable property were used. In order to verify the proposed fabrication process, we developed a diaphragm-type DE actuator using UV curable PEDOT:PSS and PDMS. The DE actuator is a disk shape with 10 mm diameter and 0.8 mm thickness. A diaphragm-type DE actuator was fabricated in the order of (1) a bottom cover, (2) a bottom compliant electrode, (3) a DE, (4) a top compliant electrode, and (5) a top cover by using UV curable material patterning. In the driving experiment, we measured an out-of-plane displacement of 55 μm when 2.5 kV was applied to the DE actuator.