Simulated annealing-based placement for microfluidic large scale integration (mLSI) chips

Microfluidic large-scale integration (mLSI) chips comprise hundreds or thousands of microvalves integrated into a chemically inert elastomeric substrate. The design of these chips is time-consuming, error-prone, and presently performed by hand. To enhance design automation, a routability-oriented placement algorithm based on simulated annealing is introduced. This paper investigates relevant issues including: (1) grid representation; (2) perturbation operations; (3) objective function; (4) uniform vs. heterogeneous component sizes; (5) spacing rules and their effect on routability; and (6) random vs. directed initial placement. Our results show how the above issues affect both the pre-routing estimate on the routability of the chips, the number of flow channel intersections (each of which requires the insertion of several microvalves), and total channel distance as reported by our router.