<bold>Process-Induced Skew Reduction in Nominal Zero-Skew Clock Trees</bold>

This work develops an analytic framework for clock tree analysis considering process variations that is shown to correspond well with Monte Carlo results. The analysis framework is used in a new algorithm that constructs deterministic nominal zero-skew clock trees that have reduced sensitivity to process variation. The new algorithm uses a sampling approach to perform route embedding during a bottom-up merging phase, but does not select the best embedding until the top-down phase. This results in clock trees that exhibit a mean skew reduction of 32.4% on average and a standard deviation reduction of 40.7% as verified by Monte Carlo. The average increase in total clock tree capacitance is less than 0.02%.