High-κ van der Waals Oxide MoO3 as Efficient Gate Dielectric for MoS2 Field-Effect Transistors

Abstract

Two-dimensional van der Waals crystals (2D vdW) are recognized as one of the potential materials to solve the physical limits caused by size scaling. Here, vdW metal oxide MoO3 is applied with the gate dielectric in a 2D field-effect transistor (FET). Due to its high dielectric constant and the good response of MoS2 to visible light, we obtained a field effect transistor for photodetection. In general, the device exhibits a threshold voltage near 0 V, Ion/Ioff ratio of 105, electron mobility about 85 cm2 V−1 s−1 and a good response to visible light, the responsivity is near 5 A/W at low laser power, which shows that MoO3 is a potential material as gate dielectric.