Efficient infrared photodetector based on three-dimensional self-assembled PbSe superlattices

Abstract

We report an efficient infrared (IR) photodetector using three-dimensional self-assembled Lead Selenide (PbSe) superlattices as an absorber. These self-assembled superlattices were synthesized using a hot solution method where the size of superlattice could be varied by controlling the reaction time and concentration of surfactants including TOP, TOPO and oleic acid. It was found that the interactions between surfactants were the major driving force for this self-organization behavior, while surface charges would also affect the self-assembly process of superlattices. An infrared photodetector with device structure ITO/PEDOT:PSS/PbSe superlattices/ZnO nanoparticles/Al showed high detectivity of 4 × 10¹⁰ Jones at 3 V bias under 830 nm infrared irradiation.