Fabrication of a high performance ZnIn2S4/Si heterostructure photodetector array for weak signal detection

摘要

Owing to their exciting electronic and optical attributes, layered materials have attracted great interest in the field of next-generation photodetectors. However, owing to their large dark current, low detectivity and small signal-to-noise ratio, the performance of photodetectors based merely on layered materials is unsatisfactory for use in weak signal detection. Integrating layered materials with mature silicon (Si) technology offers a feasible scenario to overcome these drawbacks. Herein, we report the facile synthesis of layered ZnIn2S4 nanosheets and the construction of a ZnIn2S4/Si heterostructure photodetector array for weak signal detection. Owing to the interfacial charge transfer, which significantly suppresses the dark current and accelerates the separation of the photoexcited electron-hole pairs, the fabricated ZnIn2S4/Si photodetector array presents an ultralow dark current (18 pA), superior signal-to-noise ratio (11572), stable photoswitching and high detectivity (2 x 10(12) Jones). Notably, the heterostructure device exhibits an outstanding weak signal detection capability, which has been successfully demonstrated using the detection of weak light sources including a cell phone screen, flashlight and lighter. These results demonstrate that the synergetic effect of layered materials and mature semiconductor technology shows great potential for application in next-generation optoelectronics.