Electrical Properties of Metallic and Semiconducting Transition-Metal Dichalcogenide Nanopatches.

Metallic and semiconducting nanopatches of MoS$_2$, TaS$_2$ and WSe$_2$ dichalcogenide crystals on SiO$_2$ substrates were fabricated. The crystals were synthesized by a chemical vapor transport method or obtained in natural form and cleaved by mechanical or chemical exfoliation techniques to thicknesses as small as 2nm. Electrical contact to the nanopatches was established via lithographically defined metal leads to allow measurement of electrical properties, including charge carrier mobility and Hall mobility, in field-effect transistor geometries at various temperatures. These nanopatches represent progress toward studies of electron behavior in self-assembled two-dimensional systems.