Improved optoelectronic properties of spray pyrolysis coated Zn doped Cu2O thin films for photodetector applications

Abstract

Present work deals with the preparation of pure and Cu 2 O:Zn (0, 3, 5, and 7 wt %) using the Nebulizer spray technique. The structural (XRD), morphology (AFM), energy dispersive analysis (EDX), UV–Vis spectrophotometer, photoluminescence spectrometer, and Hall measurements were used to characterize the films. XRD study confirmed the polycrystalline cubic crystal structure preferentially grown with the (111) plane orientation. With increasing the doping concentration, a considerable amount of variation in morphology and surface roughness was found in the AFM study. Optical studies revealed the variation in the band gap between 2.25 and 1.85 eV for all Zn doped Cu 2 O films. The studied samples showed highest responsivity of 2.26 AW -1 , maximum EQE of 729% and detectivity of 2.80 × 10 10 Jones respectively. The high-speed response time (3.3 s) and decay time (3.5 s) with clear repeatability properties provide a pathway to design an excellent photodetector. • Facile and low-cost fabrication of Zn@Cu 2 O thin films by nebulizer spray pyrolysis route is reported. • XRD, EDX and AFM studies confirmed the Zn doped Cu 2 O films with good crystallinity. • AFM study reveals very fine grains formation in the grown films. • The energy gap of Cu 2 O films was reduced from 2.25 to 1.85 eV on Zn content doping. • Zn@Cu 2 O films possess high performance photodetection nature compare to pure.