Abstract
To improve the power delivery network (PDN) efficiency under the consideration of scaling trends, back-side PDN has been proposed. To well utilize the remaining routing resources on the back side after constructing the PDN, a pioneering work [4] introduced a netlist planning flow capable of distributing a set of signal nets to both sides for routing. However, it failed to consider the routing blockages of the PG network, and the overlapping regions between bounding boxes of pins assigned to the front side and back side, respectively, leading to sub-optimal wirelength. To mitigate these drawbacks, we propose a PG-aware capacity calculation to adjust the bridging cell capacities and the routing capacities for accurate back-side routing resource estimation and a bounding box-based netlist planning approach. Compared to [4], our method resulted in 2% reduction in the average wirelength and 6.4% improvement in the average timing score for the critical nets. Compared to a netlist planning method that leveraged a commercial tool, our approach reduced the average wirelength by 7.4% and improved the average timing score for the critical nets by 22.2%. © 2024 ACM.