Related Experiment Video
Updated: Aug 12, 2025
04:56
Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials
Published on: July 18, 2025
150
Hysteresis-Free Contact Doping for High-Performance Two-Dimensional Electronics
Po-Hsun Ho1,2, Jun-Ru Chang1, Chun-Hsiang Chen3
1Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan.
ACS Nano
|January 30, 2023
Summary
A new two-step doping method effectively repairs defects in two-dimensional (2D) materials, enabling robust contact doping for high-performance 2D transistors and achieving record-high conductance in molybdenum disulfide (MoS2).
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Physics
Background:
- Contact doping is essential for reducing contact resistance in two-dimensional (2D) transistors.
- A robust and effective method for contact doping of 2D materials is currently lacking.
Purpose of the Study:
- To develop a novel two-step doping method for 2D materials.
- To achieve strong, hysteresis-free doping and reduce contact resistance in 2D transistors.
Main Methods:
- A two-step doping process involving defect repair was developed.
- The method was applied to monolayer molybdenum disulfide (MoS2) and Au-contact devices.
Main Results:
- Achieved a record-high sheet conductance of 0.16 mS·sq-1 for monolayer MoS2 without gating.
- Obtained high mobility and carrier concentration (4.1 × 10^13 cm-2).
- Demonstrated a low contact resistance of 1.2 kΩ·μm for a monolayer MoS2 device.
Conclusions:
- The developed method provides effective and robust contact doping for 2D materials.
- This technique is suitable for widely used transition-metal dichalcogenides.
- The method enables the fabrication of high-performance 2D transistors.
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