Abstract Monolayer semiconducting transition metal dichalcogenides (TMDCs) single‐crystal wafers have become the footstone of highly integrated circuits for next‐generation information technology. However, several critical challenges, for example, inconsistent epitaxial mechanisms, undesirable gas‐phase reactions, and introduction of defects, inhomogeneous thickness, still need to be resolved toward enhanced growth reproducibility and crystal quality. Herein, a “Trojan” metal precursor supply route is ingeniously designed for the heteroepitaxy of monolayer MoS 2 and MoSe 2 single crystals on Au(111) foils. Noteworthy, the “Trojan” metal precursor is pre‐embedded in the Au─Mo surface alloy, and released via an Au‐step‐edge‐mediated segregation process, enabling the epitaxial growth of TMDCs through concurrent high‐temperature sulfurization/selenization. This precisely controllable, separate metal precursor feeding design (from S/Se precursors), differing from the existing upstream transport or face‐to‐face metal precursor feeding routes by using metal oxides or metal‐promoter‐compound precursors, can suppress the undesirable gas‐phase reactions in principle and enable highly uniform growth of monolayer TMDCs single crystals with scalable sizes. Hereby, this work presents a novel strategy for the highly uniform preparation and epitaxial mechanism exploration of monolayer semiconducting TMDCs wafers, which should promote their applications in various emerging fields.
Hu et al. (Wed,) studied this question.