Work

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

Year: 2024

Type: article

Abstract: This study focuses on the electrical and optical properties of monolayer MoTe2 (1L‐MoTe2) flakes fabricated via gold‐mediated exfoliation, and it is demonstrated that this technique applies to the development of 1L‐MoTe2 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‐MoTe2 can be suppressed by the deposition of the hBN cap layer. The transfer characteristics of the 1L‐MoTe2 channel FETs show clear ambipolar behavior and excellent switching properties, with an on/off ratio of 105. It is shown that graphite/1L‐MoTe2 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 O2/H2O molecules. These results demonstrate that the electrical properties of gold‐exfoliated 1L‐MoTe2 strongly depend on the environmental conditions.

Source: physica status solidi (b)

DOI: 10.1002/pssb.202400374

Authors: Taku Yoshimura, Hiroshi Shigeno, Rikuto Yamamura, Kenji Watanabe, Takashi Taniguchi, Yusuke Hoshi

Institutions: Tokyo City University, National Institute for Materials Science

Language: English

Topic: 2D Materials and Applications

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,650

Funders: Ministry of Education, Culture, Sports, Science and Technology, Japan Society for the Promotion of Science