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Updated: Jun 14, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Two-dimensional phonon transport in supported graphene.
Jae Hun Seol1, Insun Jo, Arden L Moore
1Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Science (New York, N.Y.)
|April 10, 2010
Summary
Graphene
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphene exhibits exceptionally high thermal conductivity (kappa), surpassing diamond and graphite.
- This property suggests potential applications in thermal management for nanoelectronics.
- However, substrate interactions may significantly alter graphene's thermal transport properties.
Purpose of the Study:
- To experimentally determine the thermal conductivity of monolayer graphene on a silicon dioxide substrate.
- To compare the substrate-supported graphene's thermal performance with suspended graphene and other materials.
- To investigate the mechanisms responsible for any observed reduction in thermal conductivity.
Main Methods:
- Experimental measurement of thermal conductivity using techniques suitable for nanoscale materials.
- Exfoliation of monolayer graphene onto a silicon dioxide support.
- Analysis of phonon behavior and interface effects.
Main Results:
- Monolayer graphene on silicon dioxide exhibits a thermal conductivity of approximately 600 W/m·K near room temperature.
- This value remains higher than that of metals like copper.
- The measured thermal conductivity is lower than that of suspended graphene.
Conclusions:
- Graphene's high thermal conductivity is partially retained even when supported by a substrate like silicon dioxide.
- Phonon leakage and interface scattering at the graphene-support interface reduce thermal transport.
- Graphene remains a promising material for heat dissipation applications, even in substrate-bound configurations.
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