Measurements of phonon transport properties in two-dimensional graphene and hexagonal boron nitride
Speaker: Dr. Insun Jo, University of Texas, Austin
Department: Electrical Engineering
Location: Engineering Quadrangle, B418
Date/Time: Monday, June 10, 2013, 10:00 a.m. - 11:00 a.m.
Two-dimensional graphene and hexagonal boron nitride exhibit superior thermal properties, therefore may potentially offer a solution to the increasingly severe heat dissipation problem in nanoelectronics caused by increased power density. First part of this talk will be about thermal conductivity measurements of suspended single and few-layer graphene using a micro-bridge device with built-in resistance thermometers. In the second part, I am going to present thermal transport measurements on hexagonal boron nitride with different suspended lengths, which allowed us to extract the intrinsic thermal conductivity of the samples as well as the contribution of contact thermal resistance to the overall thermal measurement. Lastly, scanning thermal microscopy based on a sub-micrometer thermocouple at the apex of a micro-fabricated tip was employed to image the temperature profiles in electrically biased graphene devices with ~ 100 nm scale spatial resolution, which revealed the important heat dissipation mechanism in graphene devices.