Carbon Nanotubes Bundled Interconnects: Design Hints Based on Frequency- and Time-Domain Crosstalk Analyses

In this paper, the crosstalk problem for carbon nanotubes (CNTs) bundled interconnects is modeled in the framework of the multiconductor transmission line (MTL) theory by using a fluid description of the conduction phenomena in CNTs. Two two-port models for a two-line interconnect (one aggressor and one victim) are proposed. The first is based on the full-MTL equations coupling each CNT in the bundles. The second, which is a reduced order TL model coupling the CNT bundles, is derived from the first one and used for fast computations. The crosstalk models are used to study the impact on relevant electromagnetic performances of some actual technological and design aspects, such as the variability of the number of conducting CNTs in each bundle, their position in the cross section, the proximity of the signaling lines, the cross-sectional aspect ratio, and some advances in CNT manufacturing techniques. Both frequency- and time-domain characteristics are evaluated and compared with those of ideally scaled traditional copper interconnects. The results are compared with those obtained by simplified approaches, showing, in particular, that simple RC models may underestimate the crosstalk.