Partition-based global placement considering wire-density uniformity for CMP variations

摘要

This paper presents a multilevel hypergraph partitioning method that balances constraints on not only the cell area but also the wire weight with a partition-based global placement algorithm that maximizes the wire density uniformity to control chemical-mechanical polishing (CMP) variations. The multilevel partitioning alternately uses two FM variants in the refinement stage to give a more uniform wire distribution. The global placement is based on a top-down recursive bisection framework. The partitioning algorithm is used in the bisectioning to impact the wire density uniformity. Tests show that, with a 10% constraint, the partitioning produces solutions with more balanced edge weights that are 837% better than from hMetis, 1039.1 % better than MLPart, and 762.9% better than FM in terms of imbalance proportion and that this global placement algorithm improves ROOSTER with a more uniform wire distribution by 3.1 % on average with an increased wire length of only 3.0%.