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Updated: Aug 5, 2026
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Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
MXenes Contacts for p-type 2D Electronics
Tianchao Guo1, Maolin Chen1, Yizhou Wang1,2
1Materials Science and Engineering, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 3, 2026
Summary
Nb2CTx MXene is identified as a superior electrical contact for p-type 2D semiconductors like MoTe2. This breakthrough reduces contact resistance and enhances transistor performance, paving the way for advanced 2D electronics.
Area of Science:
- Materials Science
- Nanotechnology
- Condensed Matter Physics
Background:
- Two-dimensional (2D) materials offer unique electronic properties but require efficient electrical contacts.
- MXenes, a class of 2D transition-metal carbides and nitrides, possess metallic conductivity and tunable surface chemistry.
- Developing effective contacts for p-type 2D semiconductors is crucial for next-generation electronic devices.
Purpose of the Study:
- To systematically investigate the impact of MXene composition on electrical contact performance for p-type 2D semiconductors.
- To compare Ti3C2Tx, Nb2CTx, and Mo2CTx as contact materials for 2H-MoTe2 transistors.
- To identify the optimal MXene composition for reducing contact resistance and enhancing device performance.
Main Methods:
- Fabrication of p-type 2H-MoTe2 transistors using a polymer-assisted transfer process for high-quality interfaces.
- Systematic comparison of Ti3C2Tx, Nb2CTx, and Mo2CTx as electrical contacts.
- Electrical characterization, including measurements of contact resistance, hole mobility, and on/off current ratio.
- Temperature-dependent measurements to analyze interface properties and Schottky barrier height.
Main Results:
- Nb2CTx demonstrated superior performance as an electrical contact compared to Ti3C2Tx and Mo2CTx.
- Nb2CTx contacts significantly reduced contact resistance due to favorable band alignment with 2H-MoTe2.
- Nb2CTx/2H-MoTe2 transistors exhibited high hole mobility (~17 cm2V-1s-1) and an on/off ratio (>10^3).
- Near-ideal interface characteristics with a low Schottky barrier height (< few meV) were observed.
Conclusions:
- MXene compositional engineering is a viable strategy for optimizing electrode-semiconductor interfaces.
- Nb2CTx is a promising, scalable, high-performance contact material for p-type 2D electronics.
- This work advances the development of advanced 2D electronic devices by addressing the critical challenge of efficient electrical contacts.
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