Defect-tolerant hypercube architectures using hierarchical redundancy

This paper proposes an advanced hierarchical redundancy scheme using additional bypass linking (ABL) for defect tolerance in wafer-scale integrated circuits (WSIs) with hypercube architectures. This scheme can markedly reduce the number of nonredundant switches for connecting spares, so it enhances the yield of WSIs compared to the conventional scheme using primary link switching, when applied to full binary hypercubes (BHCs) and cube-connected cycles (CCCs). This paper also proposes an advanced BHC-like cube with hierarchical redundancy called an HR-CCT cube. The basic CCT cube consists of a set of sub-BHCs each of which provides additional torus links. These subcubes are connected to each other by a hierarchical complete connection scheme. The HR-CCT cube using ABL is also advantageous for defect tolerance, and has better network features than the redundant SHCs and CCCs.