Sequence-pair-based placement and routing for flow-based microfluidic biochips

Flow-based microfluidic biochips are attracting increasing attention with successful applications in lab-on-a-chip experiments and point-of-care diagnosis. Physical design for flow-based biochips determines the number of flow-channel intersections, and thus affects the number of microvalves. As reducing microvalves will significantly improve the overall design quality and reliability, physical design is of great importance. Typically, physical design consists of two major stages, i.e., component placement and routing. Existing works follow the step-by-step scheme, which perform placement and routing separately. The lack of interactions between the two design stages results in degraded design with large number of unfavorable channel intersections and microvalves. This paper presents a novel placement and routing method based on the sequence-pair representation, which seamlessly integrates placement and routing stages and allows iterative placement adjustment upon routing feedbacks. Experimental results show that compared with the existing work, the proposed method obtains average 54.10% improvement in flow-channel crossings, 42.15% improvement in total chip area, and 23.43% improvement in total channel length.