Effect of Deposition Time on the Electrodeposited n-Cu2O Thin Film

This work demonstrates the fabrication of Cu2O thin film onto a fluorine-doped tin oxide (FTO) glass substrate via electrodeposition method which was conducted in a solution containing copper (II) acetate monohydrate and lactic acid. While varying the deposition time ranging up to 80 minutes, the solution was kept constant at solution temperature of 40°C, solution pH 6.5 and current density-0.3 mA/cm2. The characteristics of electrodeposited Cu2O were investigated via x-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), current-voltage (I-V) test and surface profiler. The XRD results showed the intensity peak of Cu2O corresponded to reflection (111) increased when the deposition time increased. The topological characteristics from AFM characterization showed the increment of surface roughness decreased as the time increased from 5 to 60 minutes. However, the surface roughness decreased when the time reached 70 and 80 minutes. I-V characteristics of all electrodeposited Cu2O showed Ohmic behaviours indicating the successful fabrication of n-Cu2O thin film. From this study, the significant effect of deposition time of Cu2O was clearly observed and plays an important role in providing mechanism growth of the film.