Enhancing On-die PDN for Optimal Use of Package PDN with Decoupling Capacitor

In this paper, a method of enhancing the performance of on-die Power Distribution Network (PDN) and modeling of off-die PDN to utilize a maximum of package-level PDN solutions with decoupling capacitor have been proposed. To improve the on-die PDN performance, multi-stacked Cu-pillar bump RDL is provided for tighter connections between bumps and decoupling capacitor for sharing between switching instances. The proposed multi-stacked Cu-pillar bump RDL is a cost-effective solution to improve on-die PDN performance. However, reinforcing on-die PDN on active layers requires expensive and complex processes. The proposed off-die PDN modeling method can further secure the power integrity performance margin, especially when applying the decoupling capacitors. It is proposed to consider only the ground bumps in the IP area as the reference for power domain to which the decoupling capacitor is applied. This helps in revealing the potential PDN design issues of the IP.