CSL: Configurable Fault Tolerant Serial Links for Inter-die Communication in 3D Systems.

Three dimensional (3D) integrated systems become a reality nowadays, as Thru-Silicon-Via (TSV) technologies mature. 3D integration promises significant performance and energy efficiency improvements by reducing the signal travel distances and integrating more capabilities on a single chip. High integration costs, thermal management, and poor reliability and yield are major challenges of TSV based 3D chips. High structural and parametric fault rates due to manufacturing defects makes it difficult to achieve high interconnect yield using only spare-based repair solutions. In this paper we address the TSV yield issue by implementing the inter-die links of 3D chips as Configurable fault-tolerant Serial Links (CSLs). When there are not enough available functional TSVs, faults are tolerated by performing data serialization. CSLs help reduce chip costs by improving the TSV yield with very few or no spares at all. For 3D Networks-on-Chip (3D NoCs) we show that the CSL yield improvement comes with moderate area overheads (~12-26%) and small performance penalties (less than 5% average latency overhead). [ABSTRACT FROM AUTHOR]