Two-dimensional MoS2 as a new material for electronic devices

We overview fundamental properties, preparation techniques, and potential device applications of singleand few-monolayer-thick molybdenum disulde MoS2 belonging to a new emerging class of materials: 2-dimensional semiconductors. To a large extent, the interest in the 2-dimensional materials is fueled by the quest for alternatives to graphene, which is hardly suitable for electronic devices because of the lack of a band gap. A unique combination of physical properties, including exibility, high electron mobility, and optical transparency combined with a large band gap tunable from indirect 1.2 eV for bulk to direct 1.9 eV for a monolayer, make MoS2 attractive for a variety of electronic and optoelectronic devices. The first device demonstrations are very encouraging: field-effect transistors with high current ON/OFF ratios, high-sensitivity phototransistors, logic circuits, and amplifiers based on monolayer-MoS2 have been demonstrated. The layered structure of MoS2 with other transition-metal dichalcogenides (WS2 , WSe2 , MoSe2 , etc.) makes it possible to grow ultrathin, so-called van der Waals heterostructures with very abrupt interfaces and low defect density and paves the way for fabricating multilayered materials for novel electronic and optical devices. However, further progress towards potential commercialization of monolayer-MoS2 -based devices requires serious efforts in the development of scalable fabrication techniques capable of producing large-area electronic-quality material.