Significance of Annealing Temperature on Transmission Properties of ZnO Thin Film by Hydrothermal Method

In this study Zinc oxide (ZnO) thin films were prepared using a low cost hydrothermal method and investigated for the effect of different annealing temperatures. The ZnO precursor solution was made using zinc acetate dehydrate Zn(CH3COO)2.2H2O (ZAD) and hexamethylenetetramine C6H12N4(HMT). The samples were annealed at different temperatures (100°C, 200°C, 300°C, 400°C & 500°C) for 90 minutes and irradiated using refractory furnace. Thin films were analyzed using ultra violet-visible spectrophotometry, X-ray Diffraction (XRD) with Cu-Kα radiation to determine the structure of the film, four probe and two probe method for electrical properties and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDX) for surface morphology and chemical composition. Result shows the 500°C annealing produce good thin films as well as the increasing deposition time from 4 to 24 hours leads to higher crystalline films with increased transmittance.