| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
2D Materials – Preparation, Properties, Modeling & Applications
|
| Presentation Title |
Wafer-Scale Epitaxial MoS2 Monolayers Grown by Metalorganic Chemical Vapor Deposition: Effects of Growth Temperature and Pre-Growth Annealing |
| Author(s) |
Chen Chen, Nicholas Trainor, Shalini Kumari, Henrik Myja, Tilmar Kümmell, Zhiyu Zhang, Yuxi Zhang, Anuj Bisht, MuhtasimUl Karim Sadaf, Najam Sakib, Ying Han, Thomas V McKnight, Andrew Graves, Meghan Leger, Nicholas Redwing, Myeongok Kim, Dorota Anna Kowalczyk, Gerd Bacher, Nasim Alem, Yang Yang, Saptarshi Das, Joan M Redwing |
| On-Site Speaker (Planned) |
Chen Chen |
| Abstract Scope |
Epitaxial growth of MoS2 on sapphire provides films that are crystallographically well-oriented but typically contain low-angle grain boundaries (mirror twins), voids and other defects depending on growth conditions and substrate characteristics, which deteriorates 2D-FETs device performance and hinders electrical applications. In this study, we investigate microstructure, optical properties and field-effect characteristics of wafer-scale MoS2 monolayers grown by MOCVD on c-plane sapphire over a narrow window of growth temperatures (900-1000 °C) and pre-growth annealing under H2 vs H2+H2S. Studies show that MoS2 monolayers grown at an intermediate temperature of 950 °C provide an intermediate condition where the combined effects of low-angle and high-angle boundaries are minimized, and obtains the best electrical transport properties. Pre-annealing in H2S, compared to pure H2, allows the epitaxy to rotate from the step-driven R0° to thermodynamic R30° which is driven by the specific termination of the different sapphire terraces and leads to increased high-angle grain boundaries. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Thin Films and Interfaces, Characterization, Nanotechnology |