An electrostatically driven valve-less peristaltic micropump with a stepwise chamber

An electrostatically driven valve-less peristaltic micropump for gas chromatography has been developed. A stepwise chamber was first fabricated using a three-dimensional (3D) fabrication technique known as detachment lithography; the stepwise design was intended to decrease the dead volume of the device and the operation voltage by inducing zipping action. The pump itself was fabricated with a silicon substrate and a polyimide (PI) diaphragm and operated by four electrodes with a 4-phase sequencing actuation. The pump was operated in a range starting from a voltage of 60V and frequency of 4 Hz with a flow rate of 18.2 mu l/min, up to a voltage of 90V at a frequency of 6 Hz with a maximum flow rate of 33.1 mu l/min. The results showed that the minimum operating voltage of the stepwise chamber was approximately 30% lower than that of a vertical chamber with the same depth, and the power consumption per unit flow rate was also decreased by about 10%. (C) 2012 Elsevier B.V. All rights reserved.