Schottky Barrier Height of Pd/MoS2 Contact by Large Area Photoemission Spectroscopy.

MoS2, as a model transition metal dichalcogenide, is viewed as a potential channel material in future nanoelectronic and optoelectronic devices. Minimizing the contact resistance of the metal/MoS2 junction is critical to realizing the potential of MoS2-based devices. In this work, the Schottky barrier height (SBH) and the band structure of high work function Pd metal on MoS2 have been studied by in situ X-ray photoelectron spectroscopy (XPS). The analytical spot diameter of the XPS spectrometer is about 400 μm, and the XPS signal is proportional to the detection area, so the influence of defect-mediated parallel conduction paths on the SBH does not affect the measurement. The charge redistribution by Pd on MoS2 is detected by XPS characterization, which gives insight into metal contact physics to MoS2 and suggests that interface engineering is necessary to lower the contact resistance for the future generation electronic applications.