Effect of Annealing on the Dark and Illuminated I Characterization of a ZnO:Ga|Cu.sub.2O Hetero-Junction Prepared by Ultrasonic Spray System

This paper presents the Ultrasonic Spray Pyrolysis system fabrication of gallium-doped zinc oxide (ZnO:Ga)|cuprous oxide (Cu.sub.2O) thin film hetero-junction. The deposition parameters were constant for ZnO:Ga and Cu.sub.2O. Structural and optical properties of ZnO:Ga, Cu.sub.2O, and ZnO:Ga|Cu.sub.2O hetero-junction were characterized by X-Ray Diffraction method and UV-Vis spectrometry, respectively. SEM and FTIR were used to reveal the morphology and the nature of the chemical bonds. The electrical properties were measured by an Keithley I-V source meter. The ZnO:Ga|Cu.sub.2O hetero-junction was annealed at 350, 400, and 450°C and the current-voltage characteristics were measured. The band gaps of ZnO, Cu.sub.2O, and ZnO:Ga|Cu.sub.2O are ~3.27, ~2.65, and ~3.29 eV, respectively. The annealing temperature improves the hetero-junction quality.