Conduction Mechanisms in CVD-Grown Monolayer MoS2 Transistors: From Variable-Range Hopping to Velocity Saturation

• Published in: Nano letters Vol. 15; no. 8; pp. 5052 - 5058
• Main Authors: He, G, Ghosh, K, Singisetti, U, Ramamoorthy, H, Somphonsane, R, Bohra, G, Matsunaga, M, Higuchi, A, Aoki, N, Najmaei, S, Gong, Y, Zhang, X, Vajtai, R, Ajayan, P. M, Bird, J. P
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 12.08.2015
• Subjects: Crystallization; Disulfides - chemistry; Electric Conductivity; Equipment Design; Models, Molecular; Molybdenum - chemistry; Transistors, Electronic; Molybdenum disulfide; transition metal dichalcogenides; velocity saturation; 2D transistors; high-field transport
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/acs.nanolett.5b01159

We fabricate transistors from chemical vapor deposition-grown monolayer MoS2 crystals and demonstrate excellent current saturation at large drain voltages (V d). The low-field characteristics of these devices indicate that the electron mobility is likely limited by scattering from charged impurities. The current–voltage characteristics exhibit variable range hopping at low V d and evidence of velocity saturation at higher V d. This work confirms the excellent potential of MoS2 as a possible channel-replacement material and highlights the role of multiple transport phenomena in governing its transistor action.