Wafer‐Scale Oxygen‐Doped MoS2 Monolayer

Abstract Monolayer MoS 2 is an emergent 2D semiconductor for next‐generation miniaturized and flexible electronics. Although the high‐quality monolayer MoS 2 is already available at wafer scale, doping of it uniformly remains an unsolved problem. Such doping is of great importance in view of not only tailoring its properties but also facilitating many potential large‐scale applications. In this work, the uniform oxygen doping of 2 in wafer‐scale monolayer MoS 2 (MoS 2− x O x ) with tunable doping levels is realized through an in situ chemical vapor deposition process. Interestingly, ultrafast infrared spectroscopy measurements and first‐principles calculations reveal a reduction of bandgaps of monolayer MoS 2− x O x with increased oxygen‐doping levels. Field‐effect transistors and logic devices are also fabricated based on these wafer‐scale MoS 2− x O x monolayers, and excellent electronic performances are achieved, exhibiting promise of such doped MoS 2 monolayers.