ABSTRACT
Zinc oxide (ZnO) thin films were deposited on a glass substrate using cost- effective chemical bath deposition (CBD) technique at room temperature. These deposited thin films were annealed in an air atmosphere at 100, 200, 300, and 400°C for 1 h; these pristine and annealed thin films were later 90characterized for structural, compositional, morphological, optical, and electronic properties. Peaks observed in X-ray diffraction (XRD) pattern at 31.71, 36.27, and 56.29° corresponds to orientation along (100), (101), and (110) plane of ZnO materials. Raman spectra obtained for the pristine ZnO thin films represents peak at 563 and 1091 cm−1 confirming longitudinal optical (LO) and transverse optical (TO) phonon modes in ZnO thin films. The energy dispersive X-ray (EDX) spectrum that is obtained from pristine thin films confirms expected elemental composition. Surface morphology observed through atomic force microscopy (AFM) shows grain growth improvement upon post-deposition annealing treatment. Optical absorbance coefficient and energy band gaps are observed to be blue shifted on annealing treatments which can be correlated to variation in defect density states of the thin film. I–V characteristics obtained from pristine and annealed thin film shows ohmic nature of the graph which infers the semiconducting behavior of synthesized thin films.
