Thermally Limited Current Carrying Ability of Graphene Nanoribbons

This is the authors' abstract. We don't add key points for this paper.

We investigate high-field transport in graphene nanoribbons (GNRs) on SiO₂, up to breakdown. The maximum current density is limited by self-heating, but can reach >3 mA/μm for GNRs ~15 nm wide. Comparison with larger, micron-sized graphene devices reveals that narrow GNRs benefit from 3D heat spreading into the SiO₂, which enables their higher current density. GNRs also benefit from lateral heat flow to the contacts in short devices (<~0.3 μm), which allows extraction of a median GNR thermal conductivity (TC), ~80 W m^-1K^-1 at 20 ^∘C across our samples, dominated by phonons. The TC of GNRs is an order of magnitude lower than that of micron-sized graphene on SiO₂, suggesting strong roles of edge and defect scattering, and the importance of thermal dissipation in small GNR devices.