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Updated: Apr 30, 2026

Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Hole contacts on transition metal dichalcogenides: interface chemistry and band alignments
Stephen McDonnell1, Angelica Azcatl, Rafik Addou
1Department of Materials Science and Engineering, The University of Texas at Dallas , Richardson, Texas 75080, United States .
Abstract:
MoOx shows promising potential as an efficient hole injection layer for p-FETs based on transition metal dichalcogenides. A combination of experiment and theory is used to study the surface and interfacial chemistry, as well as the band alignments for MoOx/MoS2 and MoOx/WSe2 heterostructures, using photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory. A Mo(5+) rich interface region is identified and is proposed to explain the similar low hole Schottky barriers reported in a recent device study utilizing MoOx contacts on MoS2 and WSe2.
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