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

Abstract

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 cm² V^–1 s^–1