Highly Oriented WS2 Monolayers for High-Performance Electronics

Adv Mater. 2024 Dec 23:e2414100. doi: 10.1002/adma.202414100. Online ahead of print.

Abstract

2D transition-metal dichalcogenide (TMDC) semiconductors represent the most promising channel materials for post-silicon microelectronics due to their unique structure and electronic properties. However, it remains challenging to synthesize wide-bandgap TMDCs monolayers featuring large areas and high performance simultaneously. Herein, highly oriented WS2 monolayers are reproducibly synthesized through a templated growth strategy on vicinal C/A-plane sapphire wafers. Various spectroscopic characterizations confirm the high crystallographic orientation and uniformity across the entire wafers. Electronic measurements for samples transferred onto SiO2/Si substrates reveal high average field-effect mobilities of 62 and 180 cm2V-1s-1 at room temperature and 8 K, respectively. On hexagonal boron nitride substrates, these mobilities increase to 94 and 473 cm2V-1s-1, respectively. A record high saturation current density of 675 µA µm-1 is observed, outperforming the index required for high-density integration circuits in IRDS 2025. This work paves the way for the application of wide-bandgap TMDC monolayers in post-silicon electronics.

Keywords: Tungsten disulfide; field‐effect transistor; highly oriented; lattice vacancies; mobility.