Estimation of Time Delay and Repeater Insertion in Multiwall Carbon Nanotube Interconnects

A closed-form expression for estimation of the 50% time delay and an empirical formula for the optimal number of repeaters to minimize the total time delay in a single multiwall carbon nanotube (MWCNT) interconnect line with a driver and a load are presented. The comparisons between the results from these empirical formulas and those from the numerical circuit simulations show that these empirical formulas can provide accurate estimations of the time delay and the optimal number of repeaters for the MWCNT interconnects. Moreover, it is also observed that the insertion of repeaters into long MWCNT interconnects can effectively reduce the total time delay of the MWCNT interconnects, as often observed in the traditional copper interconnects. Interestingly, it further reveals that the number of repeaters needed in the MWCNT interconnects is only about one third of that in their copper counterparts.