Modeling resistance of mixed carbon nanotube bundles

Carbon nanotube (CNT) bundles are pursued for deep nanometer interconnect materials and structures due to their high conductivity and current carrying capabilities. A CNT bundle is essentially a mixture of single- and multi-wall CNTs (SWCNT and MWCNT) due to CMOS-compatible fabrication process. In order to use the mixed bundles, we must create models that can accurately characterize their conductance. In this work, we derive a diameter-dependant conductance model for MWCNTs. This MWCNT model can also incorporate the SWCNT conductance as a special case. Using this uniform model, conductance performance of the mixed bundle is analyzed and this theoretical result is consistent with the experimental result, demonstrating the efficiency and accuracy of the proposed work. Based on our results, the mixed bundles can provide up to one order of conductance improvement over copper.