High-Performance Phototransistor based on MoS2 and Multi-Layered Graphene Electrodes for Image Sensor

초록

Over the past few years, graphene and MoS2, the most famous two-dimensional (2D) layered van der Waals (vdW) materials, have been extensively studied in future nanoelectronic and nanophotonic technologies due to their unique and interesting physical properties. Multilayered graphene, gapless semiconductor, is a little bit like a semiconducting channel material and more like a metallic electrode. Unlike a graphene, MoS2 field effect transistors have shown satisfactory field effect mobility and high on/off current ratio at room temperature due to its clear band gap. In this study, we fabricated a multilayer MoS2 photo-transistor and photo-inverter logic circuit with graphene S/D electrodes for image sensor application. Our MoS2 photo-transistors show a photo-response of over ~104 A/W in the visible light range of 400 to 700 nm with nice electrical performances of mobility (~40 cm2/Vs) and on/off ratio (~105). With the MoS2 photo-inverter as a single imaging pixel, we successfully demonstrate a prototype visible image sensor as an excellent example of advanced developments in an optoelectronic system based on the 2D vdW materials.