Conventional vapor deposition or epitaxial growth of two-dimensional (2D) materials and heterostructures is conducted in a large chamber in which masses transport from the source to the substrate. Here we report a chamber-free, on-chip approach for growing a 2D crystalline structures directly in a nanoscale surface-confined 2D space. The method is based on a surprising discovery of a rapid, long-distance, non-Fickian transport of a uniform layer of atomically thin palladium (Pd) on a monolayer crystal of tungsten ditelluride (WTe2), at temperatures well below the known melting points of all materials involved. The resulting nanoconfined growth realizes a controlled formation of a stable new 2D crystalline material, Pd7WTe2 , when the monolayer seed is either free-standing or fully encapsulated in a van der Waals stack. The approach is generalizable and highly compatible with nanodevice fabrication, promising to expand the library of 2D materials and their functionalities.
@article{arxiv.2307.06477,
title = {Surface-Confined Two-Dimensional Crystal Growth on a Monolayer},
author = {Yanyu Jia and Fang Yuan and Guangming Cheng and Yue Tang and Guo Yu and Tiancheng Song and Pengjie Wang and Ratnadwip Singha and Ayelet July Uzan and Michael Onyszczak and Kenji Watanabe and Takashi Taniguchi and Nan Yao and Leslie M Schoop and Sanfeng Wu},
journal= {arXiv preprint arXiv:2307.06477},
year = {2024}
}