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Updated: Aug 5, 2026
07:12
A Standard and Reliable Method to Fabricate Two-Dimensional Nanoelectronics
Published on: August 28, 2018
Seed Layer Engineering for Effective Charge Transfer Doping of MoS2 Transistors
Sahej Sharma1,2, Shao-Heng Yang2,3, Himani Jawa2,3
1School of Mechanical Engineering, Purdue University, West Lafayette, Indiana47907, United States.
ACS Nano
|July 27, 2026
Summary
Seed layers critically impact two-dimensional semiconductor transistors. Engineering these layers controls disorder and charge transfer doping, optimizing performance in molybdenum disulfide (MoS2) logic devices.
Area of Science:
- Materials Science
- Nanotechnology
- Semiconductor Physics
Background:
- Integrating 2D semiconductors like MoS2 with dielectrics is crucial for logic technologies.
- Seed layers are typically used for dielectric adhesion but also affect doping and performance.
Purpose of the Study:
- To investigate the role of seed layers in MoS2 transistor performance.
- To understand how seed layers influence charge transfer doping and device characteristics.
Main Methods:
- Fabrication of back-gated monolayer MoS2 transistors with Ta-seed/HfOx dielectric stacks.
- Electrical characterization (threshold voltage, on-current).
- Physical characterization using Raman, photoluminescence, and X-ray photoelectron spectroscopies.
Main Results:
- Seed layer thickness and deposition conditions significantly altered threshold voltage and on-current.
- Spectroscopic analysis revealed seed layers introduce disorder and modify interfacial charge transfer.
- Optimal performance achieved with ultrathin (0.2 nm) Ta-seed layers under oxygen-poor conditions.
Conclusions:
- Seed-layer engineering is a key strategy for controlling disorder and interfacial doping in MoS2 devices.
- Multimodal spectroscopy is valuable for process development and monitoring in 2D semiconductor device fabrication.
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