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arXiv · 1702.00437

Tuning the p-type Schottky barrier in 2D metal/semiconductor interface: boron-sheet/\mose, and /\wse

Abstract

The electronic and the structural properties of two dimensional van der Waals metal/semiconductor heterostructures have been investigated through first-principles calculations. We have considered the recently synthesized borophene [Science {\bf 350}, 1513 (2015)], and the planar boron sheets (S1 and S2) [Nature Chemistry {\bf 8}, 563 (2016)] as the 2D metal layer, and the transition metal dichalcogenides (TMDCs) \mose, and \wse\ as the semiconductor monolayer. We find that the energetic stability of those 2D metal/semiconductor heterojunctions is mostly ruled by the vdW interactions; however, chemical interactions also take place in borophene/TMDC. The electronic charge transfers at the metal/semiconductor interface has been mapped, where we find a a net charge transfer from the TMDCs to the boron sheets. Further electronic structure calculations reveal that the metal/semiconductor interfaces, composed by planar boron sheets S1 and S2, present a p-type Schottky barrier which can be tuned to a p-type ohmic contact upon an external electric field.

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Willian Couto, Adalberto Fazzio, Roberto Miwa. 2017-02-01. Tuning the p-type Schottky barrier in 2D metal/semiconductor interface: boron-sheet/\mose, and /\wse. https://doi.org/10.1088/1361-648x%2Faa7f0c

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