Full-range electrical characteristics of WS2 transistors

Abstract

Transistors with chemically synthesized layered semiconductor WS2 exhibiting 105 room temperature modulation and ambipolar behavior We fabricated transistors formed by few layers to bulk single crystal WS 2 to quantify the factors governing charge transport. We established a capacitor network to analyze the full-range electrical characteristics of the channel, highlighting the role of quantum capacitance and interface trap density. We find that the transfer characteristics are mainly determined by the interplay between quantum and oxide capacitances. In the OFF-state, the interface trap density (<10 12 cm -2 ) is a limiting factor for the subthreshold swing. Furthermore, the superior crystalline quality and the low interface trap density enabled the subthreshold swing to approach the theoretical limit on a back-gated device on SiO 2 /Si substrate. V C 2015 AIP Publishing LLC.

Fast High‐Responsivity Few‐Layer MoTe2 Photodetectors

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Recent Advances in Electronic and Optoelectronic Devices Based on Two-Dimensional Transition Metal Dichalcogenides

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