Sub 20 meV Schottky barriers in metal/MoTe2 junctions

Townsend, Nicola J; Amit, Iddo; Craciun, Monica F; Russo, Saverio

Abstract

he newly emerging class of atomically-thin materials has shown a high potential for the realisation of novel electronic and optoelectronic components. Amongst this family, semiconducting transition metal dichalcogenides (TMDCs) are of particular interest. While their band gaps are compatible with those of conventional solid state devices, they present a wide range of exciting new properties that is bound to become a crucial ingredient in the future of electronics. To utilise these properties for the prospect of electronics in general, and long-wavelength-based photodetectors in particular, the Schottky barriers formed upon contact with a metal and the contact resistance that arises at these interfaces have to be measured and controlled. We present experimental evidence for the formation of Schottky barriers as low as 10 meV between MoTe2 and metal electrodes. By varying the electrode work functions, we demonstrate that Fermi level pinning due to metal induced gap states at the interfaces occurs at 0.14 eV above the valence band maximum. In this configuration, thermionic emission is observed for the first time at temperatures between 40 K and 75 K. Finally, we discuss the ability to tune the barrier height using a gate electrode.

Citation

Townsend, N. J., Amit, I., Craciun, M. F., & Russo, S. (2018). Sub 20 meV Schottky barriers in metal/MoTe2 junctions. 2D Materials, 5(2), Article 025023. https://doi.org/10.1088/2053-1583/aab56a

• Journal Article Type: Article
• Acceptance Date: Mar 9, 2018
• Online Publication Date: Mar 22, 2018
• Publication Date: Mar 22, 2018
• Deposit Date: Jul 5, 2018
• Publicly Available Date: Jul 6, 2018
• Journal: 2D Materials
• Electronic ISSN: 2053-1583
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Issue: 2
• Article Number: 025023
• DOI: https://doi.org/10.1088/2053-1583/aab56a
• Public URL: https://durham-repository.worktribe.com/output/1326767