Uniform photoresponse in thermally oxidized Ni and MoS2 heterostructures.

Non-uniform photocurrent is usually generated at the overlapped region of the heterostructures, and its potential applications may be hindered by the spatial uniformity issue of the device photoresponse. Here, nearly a uniform photoresponse at the overlapped region of the thermally oxidized Ni and molybdenum disulphide (MoS2) heterostructures is obtained. Further characterizations reveal that several nanometers Ni is rightly under the NiOx layer formed at the surface of the film in the oxidation process. The heterostructures based on layered MoS2/NiOx/Ni with highly conductive bottom Ni show a high uniform photoresponse with an external quantum efficiency (EQE) of 1.4% at 532 nm. Moreover, successful integration of multiple devices suggests a great priority for such a structure for highly integrated uniform photodetectors. [ABSTRACT FROM AUTHOR]