Interconnect Layout Optimization under Higher Order RLC Model for MCM Designs

In this paper, we study the interconnect layout optimization problem under a higher order resistance--inductance--capacitance model to optimize not only delay, but also waveform for interconnects with nonmonotone signal response in the context of multipchip-module global routing. We propose a unified approach that considers topology optimization and waveform optimization simultaneously. Using a new incremental moment-computation algorithm, we interleave topology construction with moment computation to facilitate accurate delay calculation and evaluation of waveform quality. Our algorithm considers a large class of routing topologies, ranging from shortest path Steiner trees to bounded-radius Steiner trees and Steiner routings. We construct a set of required arrival-time Steiner (RATS) trees, providing smooth tradeoffs among signal delay, waveform, and routing area. When combined with the MINOTAUR MCM global router (Cong and Madden, 1998), (Madden, 1998) that we have developed, the RATS-tree solutions prove to be effective in reducing overall routing congestion