Researchers in PML’s Semiconductor & Dimensional Metrology Division, in collaboration with researchers from George Mason University, compared silver and titanium contacts on MoS2 transistors to determine the influence of the metal–MoS2 interface.
A sophisticated suite of measurements (Raman spectroscopy, scanning electron microscopy and atomic force microscopy) was used to characterize the surface morphology and the interface between MoS2 and the metals, the properties of which affect the device behavior.
It was found that silver provides a much better electrical contact to MoS2 than the widely used titanium, with the silver-contact devices having 60 times higher current when the device is in the “on” state. These results are another step towards the advanced manufacture of high-value products based on 2D materials.
Explore further: Scientists probe the next generation of 2-D materials
More information: “Influence of Metal−MoS2 Interface on MoS2 Transistor Performance: Comparison of Ag and Ti Contacts,” Hui Yuan, Guangjun Cheng, Lin You, Haitao Li, Hao Zhu, Wei Li, Joseph J. Kopanski, Yaw S. Obeng, Angela R. Hight Walker, David J. Gundlach, Curt A. Richter, Dimitris E. Ioannou, and Qiliang Li. ACS Appl. Mater. Interfaces, Article ASAP. Publication Date (Web): [December 16, 2014] pubs.acs.org/doi/abs/10.1021/am506921y