In Situ Synthesis and Characterization of Transition Metal Dichalcogenides/Cerium Oxide Heterostructures via Sequential Pulsed Laser Deposition

Abstract

The combinations with transition metal dichalcogenides (TMDs) and other materials have a great potential application. However, the fabrication of artificial heterojunction TMDs with metal oxide is a significant challenge owing to complex processes including layer-by-layer growth and transfer of free-standing oxide layers. Multiple heterojunctions of oxides and direct TMDs also requires multi-step processes. Herein, we developed a straightforward method using sequential pulsed laser deposition (PLD) to fabricate multi-heterojunction TMDs thin films. With the multi-target carousel system, the artificially designed TMDs-based (WSe2/MoS2) superlattice (SL) and TMDs/oxide-based multi-heterojunction thin films were successfully synthesized on the centimeter-scale silicon-based substrate via an in situ PLD process. The PLD-grown multi-heterojunction TMDs films exhibited good uniformity, layer-by-layer stacking, and interlayer coupling between each TMDs layer. Also, we fabricated multi-heterojunction TMDs films as a metal-semiconductor/insulator-metal device to confirm its potential as an electronic device. We believe that our research might get inspired to develop new synthesis approaches of various TMDs/oxides heterostructures to realization of functional devices.