This work was partially supported by the National Science Foundation (NSF) under Award ECCS-1944095, the New York State Energy Research and Development Authority (NYSERDA) under Award 138126, and the New York State Center of Excellence in Materials Informatics (CMI) under Award C160186.
Nanoelectronic devices, Transition metals -- Effect on carrier transport, Semiconductors -- Design and construction, Semiconductors -- Materials
High contact resistance is one of the primary concerns for electronic device applications of two-dimensional (2D) layered semiconductors. Here, we explore the enhanced carrier transport through metal–semiconductor interfaces in WS2 field effect transistors (FETs) by introducing a typical transition metal, Cu, with two different doping strategies: (i) a “generalized” Cu doping by using randomly distributed Cu atoms along the channel and (ii) a “localized” Cu doping by adapting an ultrathin Cu layer at the metal–semiconductor interface. Compared to the pristine WS2 FETs, both the generalized Cu atomic dopant and localized Cu contact decoration can provide a Schottky-to-Ohmic contact transition owing to the reduced contact resistances by 1–3 orders of magnitude, and consequently elevate electron mobilities by 5–7 times. Our work demonstrates that the introduction of transition metal can be an efficient and reliable technique to enhance the carrier transport and device performance in 2D TMD FETs.
Liu, M., Wei, S., Shahi, S., Jaiswal, H. N., Paletti, P., Fathipour, S., ... & Li, H. (2020). Enhanced carrier transport by transition metal doping in WS 2 field effect transistors. Nanoscale. https://doi.org/10.1039/D0NR01573C