Analytical Study of Bundled MWCNT and Edged MLGNR Interconnects: Impact on Propagation Delay and Area

This research letter presents an accurate and efficient model for rough-edged multi-layered graphene nanoribbon (MLGNR) and multi-walled carbon nanotube (MWCNT) bundled interconnects. To address the impact of delay and area, an analytical finite-difference time-domain and real-time simulation based approach are considered. In order to obtain the propagation delay, an equivalent single conductor (ESC) model is accurately presented by simplifying a multi-conductor transmission line (MTL) of bundled MWCNT and MLGNR interconnects. The proposed equivalent ESC model is in good agreement to the MTL with an average deviation of 4.6% only. In order to validate the proposed model, the equivalent resistance, inductance, and capacitance values are compared with standard experimental results. It is observed that the model expression possesses a good agreement with experimental data with an average error of below 9.93%. Using the ESC-based driver-interconnect-load setup, an approximate number of MWCNTs in a densely packed bundle is obtained for a rough-edged MLGNR at 22 nm technology to obtain an equivalent delay. In order to acquire the equivalent propagation delay, a fewer number of MWCNTs in a bundle can provide similar performance as of MLGNR for below 200 μm interconnect length. Furthermore, the number of MWCNTs significantly increases for longer interconnects. Therefore, on an average, an edged MLGNR requires 97.98% lesser area compared to the bundled MWCNT for global interconnects. Hence, a rough-edged MLGNR can be treated as a most desired interconnect material as compared to MWCNT bundle for the future interconnect technology.