Role of Defects in Tuning the Electronic Properties of Monolayer WS2 Grown by Chemical Vapor Deposition

Two-dimensional transition metal dichalcogenides have already attracted enormous research interest. To understand the dependence of electronic properties on the quality and defect morphology is vital for synthesizing high quality materials and the realization of functional devices. Here, we demonstrate the mapping of the conductive variations by conducting atomic force microscopy (C-AFM) in the monolayer tungsten disulfide (WS2) grown by chemical vapor deposition. The electronic properties are strongly affected by the formation of vacancies in monolayer WS2 during growth, which is also verified by the photoluminescence. This spatial study of defects provides opportunities for optimization of the growth process for enhancing devices performance of TMDs monolayers.