Study Of Crosstalk Characteristic Of Carbon Nanotube Interconnect

Due to the feature size of VLSI continues shrinking, the process technology has moved into nanoscale (< 100 nm) region, and microelectronics has been developed into the era of nanoscale integrated circuits (IC). In previous deep sub-micron technology, interconnect issue has arised lots of concern and become one of critical issues of IC design. In nanoscale integrated circuits, interconnect is going to encounter more limitation problems, such as the increasing of metal resistivity, degradation of thermal properties and more serious reliability issue. Hence, the research of new process, new structure and new material for interconnect is becoming more and more active and important.CNT (Carbon Nanotube), as the forth form of carbon, was discovered in 1992. Since it has special electrical property, thermal property and mechanical characteristics, researchers have paid much attention on it in the recent decade. CNT has low resistance and high current density, so it may become the next generation interconnect material. In this paper, we extract the equivalent circuit of SWCNT (Single-Walled Carbon Nanotube) and DWCNT (Double-Walled Carbon Nanotube) based on electromagnetism and quantum theory. The equivalent circuit models of SWCNT bundles interconnect and DWCNT bundles interconnect considering crosstalk effect are obtained. Then we compare SWCNT bundle interconnect and DWCNT bundle interconnect with Cu interconnect for the crosstalk-induced delay and glitch performance. In order to make this research useful, we take the line width from ITRS 2006 as the standard, and build the equivalent circuits for Cu, SWCNT and DWCNT respectively. Then we take these equivalent circuits to the same interconnect system, and calculate the delay time and glitch for comparison. We find that SWCNT bundle interconnect and DWCNT bundle interconnect obviously improve the time delay performance in the intermediate level and the global level, but SWCNT bundle interconnect and DWCNT bundle interconnect have the similar crosstalk-induced glitch performance as Cu interconnect.This work has discussed comprehensively about the circuit performance of CNT as future interconnect in nanoscale IC. The proposed models and analysis results are important for future analysis and design of CNT interconnect. Also, it provides suggestions and guidelines for fabrication efforts and application of CNT.