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arXiv · 2005.13723

Staircase-like transfer characteristics in multilayer MoS2 field-effect transistors

Takuya Ohoka·Ryo Nouchi
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Abstract

Layered semiconductors, such as MoS2, have attracted interest as channel materials for post-silicon and beyond-CMOS electronics. Much attention has been devoted to the monolayer limit, but the monolayer channel is not necessarily advantageous in terms of the performance of field-effect transistors (FETs). Therefore, it is important to investigate the characteristics of FETs that have multilayer channels. Here, we report the staircase-like transfer characteristics of FETs with exfoliated multilayer MoS2 flakes. Atomic force microscope characterizations reveal that the presence of thinner terraces at the edges of the flakes accompanies the staircase-like characteristics. The anomalous staircase-like characteristics are ascribable to a difference in threshold-voltage shift by charge transfer from surface adsorbates between the channel center and the thinner terrace at the edge. This study reveals the importance of the uniformity of channel thickness.

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Takuya Ohoka, Ryo Nouchi. 2020-05-28. Staircase-like transfer characteristics in multilayer MoS2 field-effect transistors. https://doi.org/10.1088/2632-959x%2Fab70e6

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