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Updated: Jun 23, 2026
07:51
Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
Published on: February 1, 2022
Gigahertz Cutoff Frequencies and High Gain in Graphene-Based Hot-Electron Transistor Enabled by Material Engineering
Carsten Strobel1, André Heinzig1, Andre Hiess1
1Institute of Semiconductors and Microsystems, Chair of Nanoelectronics, Technische Universität Dresden, Nöthnitzer Straße 64, 01187 Dresden, Germany.
ACS Applied Materials & Interfaces
|June 20, 2026
Summary
Graphene-based hot-electron transistors (GHETs) show promise for high-frequency applications. Optimized emitter-base junctions significantly enhance performance, achieving record current gain and output current for advanced nanoelectronics.
Area of Science:
- Materials Science
- Nanoelectronics
- Solid-State Physics
Background:
- Graphene (Gr)-based hot-electron transistors (GHETs) are explored for high-frequency applications due to graphene's unique properties.
- Previous GHETs faced limitations in charge transport efficiency and scattering losses.
Purpose of the Study:
- To present GHETs with optimized emitter-base (E/B) composition for improved DC characteristics and gigahertz operation.
- To investigate the impact of E/B composition on hot electron injection, charge transport, and device performance.
Main Methods:
- Fabrication of GHETs utilizing optimized E/B junctions, including SiO2/Gr and MoS2/Gr structures.
- Characterization of DC device parameters, common-emitter current gain (beta), maximum output current, and cutoff frequencies.
Main Results:
- A record common-emitter current gain (beta) of 42 was achieved with a SiO2/Gr E/B structure.
- A MoS2/Gr E/B junction resulted in a record output current of approximately 2000 A/cm2.
- Non-optimized SiO2/Gr devices demonstrated cutoff frequencies approaching 1 GHz.
Conclusions:
- Optimized E/B composition in GHETs significantly enhances hot electron injection and charge transport.
- The achieved performance metrics represent substantial improvements, positioning GHETs as highly promising for future high-speed nanoelectronic devices.
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