Design-for-testability for continuous-flow microfluidic biochips

Flow-based microfluidic biochips are gaining traction in the microfluidics community since they enable efficient and low-cost biochemical experiments. These highly integrated lab-on-a-chip systems, however, suffer from manufacturing defects, which cause some chips to malfunction. To test biochips after manufacturing, air pressure is applied to input ports of a chip and predetermined test vectors are used to change the states of microvalves in the chip. Pressure meters are connected to the output ports to measure pressure values, which are compared with expected values to detect errors. To reduce the cost of the test platform, the number of pressure sources and meters should be reduced. We propose a design-for-testability (DFT) technique that enables a test procedure with only a single pressure source and a single pressure meter. Furthermore, the valves inserted for DFT share control channels with valves in the original chip so that no additional control signals are required. Simulation results demonstrate that this technique can generate efficient chip architectures for single-source single-meter test in all experiment cases successfully to reduce test cost, while the performance of these chips in executing applications is still maintained.