Grain boundaries (GBs) of transition metal dichalcogenide monolayers (ML) play an important role in many charge transport phenomena observed in these 2D materials. In this paper, nanoscale resolution current mapping by conductive atomic force microscopy (CAFM) has been employed for direct probing of the resistance associated to grain boundaries GBs in ML MoS 2 grown by chemical vapor deposition (CVD) onto a SiO 2/Si substrate. Local current‐voltage (I‐V) characteristics acquired within individual adjacent MoS 2 domains allowed to extract the metal/MoS 2 Schottky barrier height (Φ B≈ 0.3 eV), as well as the intra‐domain and GB resistance contributions. The high value of the GB resistance (≈ 6 times the value measured on an individual domain) can be responsible, in part, of the low field effect mobility (μ≈ 0.12 cm 2 Vs− 1) measured on back‐gated ML CVD MoS 2 field effect transistors.
1 Jan 2019
physica status solidi (RRL)–Rapid Research Letters