Thermal light emitters based on graphene directly grown on chips by etching-precipitation method

Graphene has been actively explored for on-chip nanoscale light sources, due to its small size, high brightness and fast-modulating blackbody radiation sources. However, the productivity problem is that the fabrication processes require a transfer process when mechanically exfoliated or chemical vapor deposited graphene are used, resulting in low productivity and degradation of graphene quality. Here, we fabricated a graphene-based thermal light emitter by using an etching-precipitation method that does not require the transfer process. Infrared and visible light emission was observed from the central constricted area, forming a hot spot. Raman measurements confirmed that defect healing occurred in the central hot spot of graphene due to the annealing effect caused by Joule heating. We also demonstrated that the device has long-term luminescence stability. This light emitter provides a promising avenue for the advancement of on-chip graphene light emitters.