Electrical and Optical Properties of hBN Capped MoTe₂ Monolayers Fabricated by Gold‐Mediated Exfoliation

This study focuses on the electrical and optical properties of monolayer MoTe 2 (1L‐MoTe 2 ) flakes fabricated via gold‐mediated exfoliation, and it is demonstrated that this technique applies to the development of 1L‐MoTe 2 channel field‐effect transistors (FETs). The average area of the gold‐exfoliated flakes is larger than that of conventional tape exfoliation. While the samples without an hBN cap layer are easily oxidized by atmospheric exposure for 1 day, increasing the number of nonradiative recombination centers, the surface oxidation of 1L‐MoTe 2 can be suppressed by the deposition of the hBN cap layer. The transfer characteristics of the 1L‐MoTe 2 channel FETs show clear ambipolar behavior and excellent switching properties, with an on/off ratio of 10 5 . It is shown that graphite/1L‐MoTe 2 junctions form a Schottky barrier with an energy of 280 meV, consistent with the theoretical value. By lowering the vacuum level, the gate voltage at the conductivity minimum point shifts to a negative value and the subthreshold swing decreases, implying a reduction in the interfacial trapped charge density due to the physisorption of O 2 /H 2 O molecules. These results demonstrate that the electrical properties of gold‐exfoliated 1L‐MoTe 2 strongly depend on the environmental conditions.