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Updated: May 11, 2026

Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
Published on: February 1, 2022
Vertical graphene-base hot-electron transistor
Caifu Zeng1, Emil B Song, Minsheng Wang
1Department of Electrical Engineering, University of California, Los Angeles, California 90095, USA.
Abstract:
We demonstrate vertical graphene-base hot-electron transistors (GB-HETs) with a variety of structures and material parameters. Our GB-HETs exhibit a current saturation with a high current on-off ratio (>10(5)), which results from both the vertical transport of hot electrons across the ultrathin graphene base and the filtering of hot electrons through a built-in energy barrier. The influences of the materials and their thicknesses used for the tunneling and filtering barriers on the common-base current gain α are studied. The optimization of the SiO2 thickness and using HfO2 as the filtering barrier significantly improves the common-base current gain α by more than 2 orders of magnitude. The results demonstrate that GB-HETs have a great potential for high-frequency, high-speed, and high-density integrated circuits.
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