Resolidified Chalcogen Precursors for High‐Quality 2D Semiconductor Growth
Qinke Wu, Huiyu Nong, Rongxu Zheng, Rongjie Zhang, Jingwei Wang, Liusi Yang, Bilu Liu
Abstract
Abstract Two‐dimensional (2D) semiconductors including transition metal dichalcogenides (TMDCs) have gained attention in optoelectronics for their extraordinary properties. However, the large amount and locally distributed lattice defects affect the optical properties of 2D TMDCs, and the defects originate from unstable factors in the synthesis process. In this work, we develop a method of pre‐melting and resolidification of chalcogen precursors (sulfur and selenium), namely resolidified chalcogen, as precursor for the chemical vapor deposition growth of TMDCs with ultrahigh quality and uniformity. Taking WS 2 as an example, the monolayer WS 2 shows uniform fluorescence intensity and a small full‐width at half‐maximum of photoluminescence peak at low temperatures with an average value of 13.6±1.9 meV. The defect densities at the interior and edge region are both low and comparable, i.e., (9±3)×10 12 cm −2 and (10±4)×10 12 cm −2 , indicating its high structural quality and uniformity. This method is universal in growing high quality monolayer MoS 2 , WSe 2 , MoSe 2 , and will benefit their applications.