Abstract:Valveless piezoelectric micropumps have wide applications in microfluidics and labonachip devices. In this study, piezoelectric micropumps with serial and parallel pump chambers were fabricated and comprehensively characterized. These pumps were made using a wet etching technique on a glass substrate. The dimensions of the pump chamber and diffuser/nozzle elements were the same in both configurations. The flow rates and pressures were measured for different combinations of driving signals, voltages, phases, duty ratio and symmetrical characteristic. The results show that the overall pumping performance is heavily dependent on driving conditions. Specifically, the flow rates and pressures of both micropumps increase with increasing driving voltage, and a triangle driving signal outperforms sine and square signals. It is also found that the influence of the driving signals phase, duty ratio, symmetrical characteristic on the parallel micropump is greater than that on the serial micropump. The flow rate and pressure of the serial micropump both reach their maximum values at a phase difference of ±180° with a sinesine signal combination for the two chambers;to the parallel micropump,the phase difference is 0°. This is consistent with the working principle of the serial micropump. Overall, the performance of the parallel micropump is better than that of the serial micropump for all combinations of driving parameters. The maximum flow rate and pressure are 173 μL/min and 490.8 Pa respectively for the parallel micropump and 83.1 μL/min and 190.3 Pa respectively for the serial micropump.