Manufacture and Performance Comparison of Two Kinds of Self-Priming Micropump Driven by PZT

Micropump is a key element in micro total analysis.In order to solve some problems, such as complex fabrication, bubble tolerance and reliability, two kinds of Micropumps, which are driven by bimorph and applied in microflow control chemical analysis, were studied in design of structure, working principle, fabrication process, performance and structure parameter. These two kinds of micropumps can pump both gas and liquid. One consists of a silicon chip and an active microvalve which is also Polydimethylsiloxane diaphragm, and the other is integrated with a active microvalve, a check microvalve and a pump chamber. The micropumps are characterized by simple structure, easy fabrication, convenient operation and self-priming. This structrure micropump can solve some problems, such as complex fabrication, bubble tolerance and reliability. when applied voltage is 100 V(square wave at 35 Hz) and backpressure keeps zero, the maximum flow rate and the backpressure of micropump with an active valve are about 5 000 μL/min and 5 kPa, respectively, while that of micropump with the combination of check valve and active valve reach 5 410 μL/min and 15 kPa, respectively. The latter is better than the former in performance, especially in backpressure.