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arXiv · 1403.5511

Indirect doping effects from impurities in MoS$_2$/BN heterostructures

Roland Gillen·John Robertson·Janina Maultzsch
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Abstract

We performed density functional theory calculations on heterostructures of single layers of hexagonal BN and MoS$_2$ to assess the effect of doping in the BN sheet and of interstitial Na atoms on the electronic properties of the adjacent MoS$_2$ layer. Our calculations predict that $n$-doping of the boron nitride subsystem by oxygen, carbon and sulfur impurities causes noticeable charge transfer into the conduction band of the MoS$_2$ sheet, while $p$-doping by beryllium and carbon leaves the molybdenum disulphide layer largely unaffected. Intercalated sodium atoms lead to a significant increase of the interlayer distance in the heterostructure and to a metallic ground state of the MoS$_2$ subsystem. The presence of such $n$-dopants leads to a distinct change of valence band and conduction band offsets, suggesting that doped BN remains a suitable substrate and gate material for applications of $n$-type MoS$_2$.

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Roland Gillen, John Robertson, Janina Maultzsch. 2014-03-21. Indirect doping effects from impurities in MoS$_2$/BN heterostructures. https://doi.org/10.1103/physrevb.90.075437

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