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Modulation Doping of Single-Layer Semiconductors for Improved Contact at Metal Interfaces
Yeonchoo Cho1,2, Gabriel R Schleder3, Daniel T Larson2
1Samsung Advanced Institute of Technology, Samsung Electronics, Suwon 16678, Republic of Korea.
Nano Letters
|November 28, 2022
Summary
Modulation doping reduces metal-semiconductor contact resistance in 2D materials. This technique, placing a doping layer opposite the metal-semiconductor interface, lowers Schottky barriers for improved electronic device performance.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Two-dimensional (2D) materials offer potential for advanced semiconductor miniaturization.
- Metal-semiconductor contact resistance is a critical bottleneck for device performance.
Purpose of the Study:
- To propose and investigate modulation doping as a method to reduce contact resistance in 2D materials.
- To demonstrate the effectiveness of modulation doping for 2D semiconductor-metal interfaces.
Main Methods:
- Utilized first-principles calculations to determine band alignment.
- Simulated modulation doping using a 2D MXene layer adjacent to a WSe2 channel.
- Analyzed the impact on Schottky barrier height and contact resistance with various metal contacts.
Main Results:
- Modulation doping significantly reduces the Schottky barrier height.
- Contact resistance at the metal-semiconductor interface is effectively lowered.
- Demonstrated feasibility with WSe2 channels and MXene doping layers, showing Fermi level shifts across the band gap.
Conclusions:
- Modulation doping is a viable strategy to overcome contact resistance limitations in 2D electronic devices.
- The proposed method is broadly applicable to various 2D semiconductors and doping layers.
- Enables further miniaturization and improved performance of next-generation electronic devices.
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