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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Highly tunable local gate controlled complementary graphene device performing as inverter and voltage controlled
Wonjae Kim1, Juha Riikonen, Changfeng Li
1Department of Micro- and Nanosciences, Aalto University, Tietotie 3, FI-02150 Espoo, Finland.
Nanotechnology
|September 10, 2013
Summary
This study demonstrates a graphene field-effect transistor (FET) with local back-gate control for tunable characteristics. This enables low-voltage operation and versatile configurations for advanced logic circuits.
Area of Science:
- Materials Science
- Nanotechnology
- Electronics Engineering
Background:
- Graphene field-effect transistors (FETs) offer potential for advanced electronics.
- Controlling doping in graphene channels is crucial for device performance.
- Unintentional doping variations in chemical vapor deposition (CVD) graphene pose challenges.
Purpose of the Study:
- To develop a graphene FET with independently controllable electrostatic doping.
- To achieve tunable device characteristics and compensate for doping variations.
- To explore novel configurations and applications in logic circuitry.
Main Methods:
- Fabrication of single-layer CVD graphene FETs with separated local back-gates.
- Utilizing local back-gate control for electrostatic doping of graphene channels.
- Operating devices at room temperature with low bias voltages.
Main Results:
- Demonstrated highly tunable device characteristics through independent control of electrostatic doping.
- Achieved device operation with very low supply voltage (VDD).
- Successfully compensated for unintentional doping variations in CVD graphene.
- Obtained both p-n and n-p configurations via electrostatic doping.
- Switched device operation between inverter and voltage-controlled resistor modes.
Conclusions:
- Local back-gating provides precise control over graphene FET doping and characteristics.
- The developed device architecture enables low-power operation and compensates for graphene variability.
- This approach opens new avenues for graphene-based logic circuitry and electronic applications.
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