Scaling of High-Field Transport and Localized Heating in Graphene Transistors

Micro & Nanotechnology Lab, University of Illinois, Urbana-Champaign, Illinois 61801, United States.
ACS Nano (Impact Factor: 12.88). 09/2011; 5(10):7936-44. DOI: 10.1021/nn202239y
Source: PubMed


We use infrared thermal imaging and electrothermal simulations to find that localized Joule heating in graphene field-effect transistors on SiO(2) is primarily governed by device electrostatics. Hot spots become more localized (i.e., sharper) as the underlying oxide thickness is reduced, such that the average and peak device temperatures scale differently, with significant long-term reliability implications. The average temperature is proportional to oxide thickness, but the peak temperature is minimized at an oxide thickness of ∼90 nm due to competing electrostatic and thermal effects. We also find that careful comparison of high-field transport models with thermal imaging can be used to shed light on velocity saturation effects. The results shed light on optimizing heat dissipation and reliability of graphene devices and interconnects.

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    • "Because of that limitation, a practical GFET needs a top-gate [5]. It is worth to note at this stage, that the high carrier mobility and the unique band structure of graphene make it very promising for various FET applications [5] [6] [7], especially in the field of detection of different physical, chemical and biological factors which strongly influence electrical properties of the graphene layer. "
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