The Delay, Energy, and Bandwidth Comparisons between Copper, Carbon Nanotube, and Optical Interconnects for Local and Global Wiring Application

The interconnect bottleneck presents a compelling reason to explore novel interconnect architectures. We compare two promising interconnects: carbon nanotube (CNT) and optical, with traditional Cu/low-K wires. We find that the optical wires yield the lowest latency and the highest bandwidth density. However, in terms of a system's top- down, novel, metric-bandwidth density per latency per power, CNTs can yield comparable performance to optical wires provided a certain mean free path and packing density is achieved. We quantify these technology parameters and also examine the impact of CNT diameter and bundle width on the performance comparison with Cu/low-K.