Synthesis and Characterisation of Copper Oxide Thin Films Using Successive Ionic Layer Adsorption Reaction (SILAR) Method

Abstract

CuxO thin films were synthesized on glass substrate by using a simple chemical method; successive ionic layer adsorption reaction (SILAR). The effects of bath pH and temperature on the structural, morphological and optical properties of the films were investigated. The films were prepared by successively dipping them for 20 s each in a solution of 1 M NaOH and then in a solution of 0.1M copper complex. Temperature of the NaOH solution was varied from room temperature to 70oC, while that of the copper complex solution was maintained at room temperature. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) , ultraviolet-visible spectroscopy (UV-VIS) and fourier transform infrared (FTIR) spectroscopy. XRD studies confirmed that the films were polycrystalline with both Cu2O and CuO crystallographic phases existing depending on the pH of the solution bath. The calculated crystallite size from the XRD measurement was found to be in the range ∼1.52 - 1.67Å. SEM micrograph revealed that the grains were distributed evenly over the substrate surface. The bandgap value was found to be in the range, 1.6eV-2.0 eV. Keywords: Copper Oxide, SILAR, pH, Temperature.