Chalcogen vacancies in monolayer transition metal dichalcogenides and Fermi level pinning at contacts
Change log
Authors
Guo, Y
Liu, D
Robertson, J
Abstract
jats:pIt is predicted that Schottky barriers of the transition metal dichalcogenides MoSe2, MoTe2, WS2, WSe2, and WTe2 will suffer less from Fermi level pinning by chalcogen vacancies than does MoS2, because their vacancy formation energies are larger. The reduction in vacancy numbers will allow a greater degree of Schottky barrier height tuning by varying metal work function of the contacts in these compounds. The vacancy levels of WS2, WSe2 and MoSe2, and MoTe2 are also calculated to lie nearer midgap, so that ambipolar conduction will be easier in these compounds than in MoS2.</jats:p>
Description
Keywords
Vacancies, Band gap, Fermi levels, Molybdenum, Density functional theory
Journal Title
Applied Physics Letters
Conference Name
Journal ISSN
0003-6951
1077-3118
1077-3118
Volume Title
106
Publisher
AIP Publishing
Publisher DOI
Sponsorship
Engineering and Physical Sciences Research Council (EP/J011592/1)
The authors are grateful for financial support from the National Natural Science Foundation of China (Grant No.51105222), Beijing Research Program (Grant No. 100322002).