Impact of electron-phonon scattering on the performance of carbon nanotube interconnects for GSI

While electron mean-free path in carbon nanotubes can be as large as several micrometers for small bias voltages, for large biases electrons get backscattered by optical and zone-boundary phonons and nanotube resistance can increase by more than 100 times. This letter reveals this kind of backscattering has a small impact (error <25%) in most interconnect applications of carbon nanotubes in which adequate numbers of nanotubes are connected in parallel. This is mainly due to relatively small electric fields along nanotubes when they are used as interconnects. This is in sharp contrast with transistor applications of carbon nanotubes in which transconductance degrades considerably by electron-phonon scatterings unless their channels are made ultrashort (∼10 nm).