Interfacial Gated Graphene Photodetector with Broadband Response

Abstract Image

A a lot stronger interfacial gating impact was noticed within the graphene/HfO2/Si photodetector compared with that within the graphene/SiO2/Si photodetector. We discovered that this enchancment was as a result of larger interface state density on the HfO2/Si interface and the upper dielectric fixed of the HfO2 layer. The photoresponsivity of the graphene/HfO2/Si photodetector is as excessive as 45.8 A W–1. Germanium and amorphous MoS2 (a-MoS2) had been used to arrange graphene/HfO2/Ge and graphene/HfO2/a-MoS2 photodetectors, additional demonstrating the excessive effectivity of the interfacial gating mechanism for photodetection. Due to the 0.196 eV bandgap of a-MoS2, which was verified in our earlier report, the graphene/HfO2/a-MoS2 photodetector realized ultrabroadband photodetection over the vary from 473 nm (seen) to 2712 nm (mid-infrared) at room temperature with photoresponsivity as excessive as 5.36 A W–1 and response time as quick as 68 μs, which signify important enhancements from the corresponding properties of the pure a-MoS2 photodetectors in our earlier report and are comparable with these of state-of-the-art broadband photodetectors. By taking full benefit of the interfacial gating mechanism, a quick response, excessive photoresponsivity and ultrabroadband photodetection had been achieved concurrently. These interfacial gated graphene photodetectors additionally provide easy fabrication and full semiconductor course of compatibility. The benefits described right here point out that the proposed photodetectors have important potential to be used in digital and optoelectronic functions and provide a brand new path towards the event of ultrabroadband photodetectors.