A Fast and Robust Global Router with Capacity Reduction Techniques

As design rules become more complex in new technology nodes, signal routing presents increasing challenges. In order to reduce the complexity, routing is typically divided into global routing (GR) and detailed routing (DR). However, a feasible GR solution may not always translate to a feasible DR solution due to resource mismatches between the two stages. In this work, we propose capacity reduction techniques that are applied in GR while aiming to enhance detailed-routability and bridge the mismatches between GR and DR. Encouraging experimental results demonstrate that after including the proposed capacity reduction techniques, the outdated open-source global router NTHU-Route 2.0 is revitalized and outperforms the state-of-the-art global router of TritonRoute-WXL. We achieve all DRC-clean solutions with 7.8% less via usage, 29% less non-preferred usage, and 2% DR quality score improvement while only increasing wirelength by 0.4%. Additionally, our GR runtime and DR runtime are respectively 44% and 31% shorter.