Large area, high responsivity, fast and broadband graphene/n-Si photodetector

A graphene/silicon heterojunction device has been realized to overcome many different requests necessary to make it a versatile, widely used and competitive detector. The obtained photodetectors which operate at room temperature, are sensitive in the spectral region from the ultraviolet (240 nm) to the infrared (2000 nm) and they can be used in different configurations that allow a high responsivity up to 107 A/W, a rise time of a few ns, an external quantum efficiency more than 300%, and a linear response for different light sources. This is allowed by the high quality of the graphene deposited on a large area of 8 mm2, and by the interdigitated design of the contacts, both preserving the excellent properties of graphene when switching from a nanoscale to the macroscopic dimensions of commonly used devices