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A planar PDMS micropump based on in-contact low-leakage check valves

This paper presents a poly(dimethylsiloxane) (PDMS) micropump with a simple planar design that incorporates check valves and a pumping chamber into one single layer, allowing for reliable operation and easy system integration. This micropump mainly consists of a pneumatically driven thin membrane, and a pumping chamber sandwiched between two in-plane check valves. The novelty of the micropump lies in the use of the in-plane in-contact valves based on the simple flap-stopper configuration to allow minimal reverse leakage critically improving the reliability of the micropump operation. In a systematic characterization, we have investigated the micropump operation with respect to key parameters including the driving pneumatic pressure, the pumping chamber height, and backpressure. Experimental results demonstrate that this micropump is capable of reliably generating a maximum flow rate of 41 μL/min, and operating stably against a backpressure up to 25 kPa.