Spatially precise light-activated dedoping in wafer-scale MoS2 films

2D materials, particularly transition metal dichalcogenides (TMDCs), have shown great potential for microelectronics and optoelectronics. However, a major challenge in commercializing these materials is the inability to effectively dope them at a wafer scale with high spatial fidelity. We use interface chemistry with the underlying substrate oxide and concomitant exposure to visible light in ambient conditions for photo-dedoping wafer scale MoS2. We hypothesize that the oxide layer traps photoexcited holes, leaving behind long-lived electrons that become available for surface reactions with ambient air at sulfur vacancies resulting in dedoping. Additionally, we showcase high fidelity spatial control over the dedoping process, by laser writing, and fine control over the degree of doping by modulating the illumination time and power density. This localized change in MoS2 doping density is very stable (at least 7 days) and robust to processing conditions like high temperature and vacuum. The scalability and ease of implementation of this approach can address one of the major issues preventing the “Lab to Fab” transition of 2D materials and facilitate its seamless integration for commercial applications in multi-logic devices, inverters, and other optoelectronic devices.