Growth and characterization of electro-deposited Cu_2O and Cu thin films by amperometric I-T method on ITO/glass substrate

摘要

Cuprous oxide and copper thin films were potentiostatically electro-deposited over indium-tin oxide (ITO) coated glass substrate with two different aqueous electrolytes: 0.1 M KNO_3 solution in comparison with the 0.05 M CH_3COOH/CH_3COONa (pH = 5.7) solution. Cyclic voltam-metry (CV) was used to determine the optimal deposition potentials. A single pair redox peaks were observed in the CV for 0.05 M CuSO_4 in the buffer solution, while two redox couples were observed in the KNO_3 solution. X-ray diffraction (XRD) and X-ray photo spectroscopy (XPS) revealed that in the buffer electrolyte the deposition for Cu_2O, Cu and co-deposition alloy were formed at more negative potentials than in the KNO_3. Furthermore, periodic structure can be obtained by controlling the deposition potentials in KNO_3 with CuSO_4 solution. The structural and morphological properties of the films have been investigated by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM).