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arXiv · 2103.14812

Effect of High-k Dielectric Layer on 1/f Noise Behavior in Graphene Field-Effect Transistors

Yifei Wang·Vinh X. Ho·Zachary. N. Henschel·Michael P. Cooney·Nguyen Q. Vinh
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Abstract

We report the 1/f noise characteristics at low-frequency in graphene field-effect transistors that utilized a high-k dielectric tantalum oxide encapsulated layer (a few nanometers thick) placed by atomic layer deposition on Si3N4. A low-noise level of ~ 2.2 x 10^(-10) Hz-1 has been obtained at f = 10 Hz. The origin and physical mechanism of the noise can be interpreted by the McWhorter context, where fluctuations in the carrier number contribute dominantly to the low-frequency noise. Optimizing fabrication processes reduced the number of charged impurities in the graphene field-effect transistors. The study has provided insights into the underlying physical mechanisms of the noise at low-frequency for reducing the noise in graphene-based devices.

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Yifei Wang, Vinh X. Ho, Zachary. N. Henschel, Michael P. Cooney, Nguyen Q. Vinh. 2021-03-27. Effect of High-k Dielectric Layer on 1/f Noise Behavior in Graphene Field-Effect Transistors. https://doi.org/10.1021/acsanm.1c00154

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