Performance Comparisons Between Cu/Low-$\kappa$, Carbon-Nanotube, and Optics for Future On-Chip Interconnects

Abstract

In this letter, we compare the performance of carbon nanotubes and optical interconnects with the scaled Cu/Iow- <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">kappa </i> interconnects for future high-performance integrated circuits. We present these comparisons in terms of both commonly used metrics, such as latency, energy per bit (power dissipation), as well as by demonstrating an explicit relationship between system-relevant metrics such as bandwidth density, power density and latency. We find that for long wires (~10 mm) both carbon nanotubes and optical interconnects outperform future Cu wires with optical interconnects having lower energy per bit and latency. For short wires (~1 mm), carbon-nanotube wires outperform both Cu and optical interconnects.