Transistors and tunnel diodes enabled by large-scale MoS2 nanosheets grown on GaN

Abstract

We report growth, fabrication, and device results of MoS2-based transistors and diodes implemented on a single 2D/3D material platform. The 2D/3D platform consists of a large-area MoS2 thin film grown on SiO2/p-GaN substrates. Atomic force microscopy, scanning electron microscopy, and Raman spectroscopy were used to characterize the thickness and quality of the as-grown MoS2 film, showing that the large-area MoS2 nanosheet has a smooth surface morphology constituted by small grains. Starting from the same material, both top-gated MoS2 field effect transistors and MoS2/SiO2/p-GaN heterojunction diodes were fabricated. The transistors exhibited a high on/off ratio of 105, a subthreshold swing of 74 mV dec−1, field effect mobility of 0.17 cm2 V−1 s−1, and distinctive current saturation characteristics. For the heterojunction diodes, current-rectifying characteristics were demonstrated with on-state current density of 29 A cm−2 and a current blocking property up to −25 V without breakdown. The reported transistors and diodes enabled by the same 2D/3D material stack present promising building blocks for constructing future nanoscale electronics.