Epitaxial Growth of Vertically Aligned Antimony Selenide Nanorod Arrays for Heterostructure Based Self-Powered Photodetector

摘要

Antimony selenide (Sb_2Se_3) has garnered significant attention with its extraordinaryoptical and optoelectronic properties for optical and optoelectronic devicessuch as broadband photodetectors. The trends emerge in the synthesis ofSb_2Se_3 over a semiconducting substrate for the direct formation of heterostructures,which facilitate a pn junction for self-powered photodetector. 1D Sb_2Se_3nanorods are preferred to boost the charge carrier transport along the longitudinaldirection as well as the optical absorption by light trapping. Great challengesremain for the vertical growth of nanorods. In this work, the preciselyvertical alignment of Sb_2Se_3 nanorod arrays has been achieved in an epitaxialgrowth manner by selecting a lattice-matching substrate, namely, boron-dopedZnO (110) surface. The directly grown boron-doped ZnO/Sb_2Se_3 nanorod arraysheterostructure leads to a high-performance broadband photodetector.Eventually,the device demonstrates extraordinary figure-of-merit parameters, i.e.,responsivity, on/off ratio, and specific detectivity. Furthermore, device simulationpredicts the theoretical limit of the photodetector performances on thecondition of suppressed defect density of the Sb_2Se_3. These results may shedlight on the investigation of controlled growth of low-dimensional materials,self-powered photodetectors, and related optic and optoelectronic devices.