Controlled Synthesis of ZrS2 Monolayer and Few Layers on Hexagonal Boron Nitride.

Group IVB transition metal (Zr and Hf) dichalcogenide (TMD) monolayers can have higher carrier mobility and higher tunneling current density than group VIB (Mo and W) TMD monolayers. Here we report the synthesis of hexagonal ZrS2 monolayer and few layers on hexagonal boron nitride (BN) using ZrCl4 and S as precursors. The domain size of ZrS2 hexagons is around 1-3 μm. The number of layers of ZrS2 was controlled by tuning the evaporation temperature of ZrCl4. The stacking angle between ZrS2 and BN characterized by transmission electron microscopy shows a preferred stacking angle of near 0°. Field-effect transistors (FETs) fabricated on ZrS2 flakes showed n-type transport behavior with an estimated mobility of 0.1-1.1 cm(2) V(-1) s(-1).