Reliability, failure, and fundamental limits of graphene and carbon nanotube interconnects

We review recent results concerning reliability and failure (due to heating) of interconnects based on metallic single-walled carbon nanotubes (SWNTs), graphene, and graphene nanoribbons (GNRs). We examine both intrinsic power dissipation within the interconnect as well as extrinsically to adjacent materials. Fundamental reliability limits are different in the diffusive and quasi-ballistic transport regimes. Thermal engineering in the diffusive regime has recently enabled us to reach current densities up to ~4 GA/cm² for SWNTs and ~2 GA/cm² for GNRs. However, short carbon-based interconnects (e.g. L <; 500 nm) enter a quasi-ballistic regime where heat sinking is dominated by the contacts, and narrow GNRs are in an edge-limited regime (W <; 200 nm), where thermal conductivity is dependent on device dimensions.