Multi-step PDMS curing and a controlled separation method for mass manufacturing of high-performance and user-friendly micro-devices: valved micropumps

Abstract

Although valved micropumps have powerful performance, their popularized application is limited by high technical barriers and high costs brought by complex microstructures. Herein, we propose a multi-step PDMS curing method and a local PDMS separation strategy to achieve mass, standardized, and low-cost manufacturing of valved micropumps, solving their popularized problems by promoting role separation between manufacturers and users. The multi-step curing and the centralized structural layout enable a volume 20 times smaller than other valved micropumps. The lithography mold quality is the main reason for only 74% yield, and using metal molds would be a better alternative. Theoretical analysis shows that the thickness and diameter of the pump membrane are the main factors in designing different driving capabilities of the micropump. By driving the micropump through periodic fluid pressure, the results show that the flow rate is positively related to the input pressure and exhibits two flow rate formation mechanisms at high and low frequencies. Its powerful back pressure generating ability also indicates that the micropump has wide application prospects as injection pumps. The micropump also demonstrates tremendous flexibility and convenience in integration, driving, and application. The multi-step PDMS curing and controlled separating ideas show popularization value for other microfluidic components, such as one-way valves, hoping to innovate the microfluidics field.