Diffusion-driven congestion reduction for substrate topological routing

Abstract

Off-chip substrate routing for high density packages is challenging, and the existing substrate routing algorithms often result in a large number of unrouted nets that have to be routed manually. This paper develops an effective yet efficient diffusion-driven method D-Router to improve routability by a simulated diffusion process based on the duality between congestion and concentration. Compared with a recently published A*-based algorithm used in a state of the art commercial tool and with similar routability and runtime as the negotiation based routing, D-Router reduces the number of unrouted nets by 4.6x with up to 94x runtime reduction.