ACCNT: A Metallic-CNT-Tolerant Design Methodology for Carbon Nanotube VLSI: Analyses and Design Guidelines

摘要

We present analyses for ACCNT (pronounced as “accent”), which is a solution to the metallic-nanotube problem that does not require any metallic-nanotube removal of any kind. ACCNT uses asymmetrically correlated carbon nanotubes to achieve metallic-nanotube tolerance, delivering high ON–OFF ratios while preserving current drive. We analyze the ACCNT methodology in terms of its tradeoffs and explore optimizations that may serve as future design guidelines. We also investigate circuit-level considerations and the impact of density variation on the ACCNT design. We find that ACCNT can improve the yield of a one-million transistor chip from 0% (conventional CNT design) up to 99% at a cost of $hbox{3.3}times$ area overhead if the fraction of semiconducting CNTs is improved to 99.9%.