Related Experiment Video
Updated: Dec 21, 2025
08:50
Preparation of Large-area Vertical 2D Crystal Hetero-structures Through the Sulfurization of Transition Metal Films for Device Fabrication
Published on: November 28, 2017
9.5K
Area-Selective Atomic Layer Deposition of Two-Dimensional WS2 Nanolayers.
Shashank Balasubramanyam1, Marc J M Merkx1, Marcel A Verheijen1,2
1Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
ACS Materials Letters
|May 19, 2020
Summary
Researchers developed area-selective atomic layer deposition (AS-ALD) for bottom-up fabrication of 2D tungsten disulfide (WS2) nanolayers. This novel method enables precise WS2 growth on specific surfaces for advanced nanoelectronics.
Area of Science:
- Materials Science
- Nanotechnology
- Semiconductor Physics
Background:
- Two-dimensional (2D) materials like tungsten disulfide (WS2) are crucial for next-generation nanoelectronics.
- Current top-down fabrication methods struggle with precise control of 2D materials at the nanoscale.
- Bottom-up approaches are needed for controlled integration of 2D materials in device architectures.
Purpose of the Study:
- To pioneer a bottom-up fabrication method for 2D WS2 nanolayers using area-selective atomic layer deposition (AS-ALD).
- To demonstrate precise control over WS2 deposition on specific substrates for nanoelectronic applications.
Main Methods:
- Developed an ABC-type plasma-enhanced AS-ALD process using acetylacetone inhibitor, a tungsten precursor, and H2S plasma.
- Achieved selective WS2 growth at a low temperature of 250 °C.
- Utilized in situ spectroscopic ellipsometry and ex situ X-ray photoelectron spectroscopy for growth analysis.
Main Results:
- Demonstrated selective WS2 growth on SiO2 while effectively blocking growth on Al2O3.
- Confirmed crystalline WS2 formation on SiO2 via sharp Raman peaks after annealing up to 450 °C.
- Showed selective growth on various 2D materials and transition metal oxides, with blocking on HfO2 and TiO2.
Conclusions:
- The developed AS-ALD process enables precise, bottom-up fabrication of 2D WS2 nanolayers.
- This technique offers a pathway for controlled integration of 2D materials in nanoelectronic devices.
- The study lays the groundwork for area-selective ALD of other 2D materials.
