Comprehensive Model for High-Speed Current-Mode Signaling in Next Generation MWCNT Bundle Interconnect Using FDTD Technique

The performance of current-mode signaling (CMS) scheme in carbon nanomaterial based multiwall carbon nanotube (MWCNT) bundle on-chip interconnect using finite-difference time-domain (FDTD) technique is investigated in the present paper. A very comprehensive model that analyzes both the traditional copper and the next-generation MWCNT bundle interconnects is presented. Further, this model is applicable for both the conventional voltage-mode signaling (VMS) and the delay-efficient CMS schemes. The number of MWCNT shells in a bundle interconnect is varied, and it is analyzed that MWCNTs with larger number of shells have better performance than both MWCNTs consisting of lesser number of shells and the copper interconnects. It is analyzed that CMS scheme has superior performance than VMS scheme in terms of smaller propagation delay and reduced crosstalk-induced delay. Various analyses have been performed for 32-nm technology node and are validated using SPICE simulations. The results obtained from the proposed FDTD based model and SPICE are found to be in close agreement, and the maximum error is within 3%.