NanoIR Featured Publications

Nanoscale Joule Heating, Peltier Vooling and Current Crowding at Graphene–Metal Contacts

April 3, 2011

Kyle L. Grosse, Myung-Ho Bae, Feifei Lian, Eric Pop, and William P. King


The performance and scaling of graphene-based electronics is limited by the quality of contacts between the graphene and metal electrodes. Here, we use atomic force microscopy to measure the temperature distributions at the contacts of working graphene transistors with a spatial resolution of ∼10, allowing us to identify the presence of Joule heating, current crowding and thermoelectric heating and cooling. Our data indicate that thermoelectric effects account for up to one-third of the contact temperature changes, and that current crowding accounts for most of the remainder. Modelling predicts that the role of current crowding will diminish and the role of thermoelectric effects will increase as contacts improve.