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arXiv · 1806.01713

Optimized single-layer MoS2 field-effect transistors by non-covalent functionalisation

Abstract

Field-effect transistors (FETs) with non-covalently functionalised molybdenum disulfide (MoS2) channels grown by chemical vapour deposition (CVD) on SiO2 are reported. The dangling-bond-free surface of MoS2 was functionalised with a perylene bisimide derivative to allow for the deposition of Al2O3 dielectric. This allowed the fabrication of top-gated, fully-encapsulated MoS2 FETs. Furthermore, by the definition of vertical contacts on MoS2, devices, in which the channel area was never exposed to polymers, were fabricated. The MoS2 FETs showed high mobilities for transistors fabricated on SiO2 with Al2O3 as top-gate dielectric. Thus, gate-stack engineering using innovative chemistry is a promising approach for the fabrication of reliable electronic devices based on 2D materials.

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HyunJeong Kim WungYeon Kim, Maria O'Brien, Niall McEvoy, Chanyoung Yim, Mario Marcia, Frank Hauke, Andreas Hirsch, Gyu-Tae Kim, Georg S. Duesberg. 2018-06-05. Optimized single-layer MoS2 field-effect transistors by non-covalent functionalisation. https://arxiv.org/abs/1806.01713

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