Effect of Annealing Temperatures on the Color Properties of Copper Oxide Films Prepared by the Sol-Gel Technique

Abstract

Sol-gel spin coating was employed to produce thin films on the glass substrate, which were subsequently heated to 300,400, 500, and 600 degrees for annealing. The effect of annealing temps on some physical features of the prepared films, such as XRD, AFM, FESEM, and UV-visible spectrophotometer, was studied. X-ray diffraction patterns showed the coexistence of two phases, Cu2O and CuO. According to the AFM findings, the root mean square (RMS) for thin films has been found to increase from 50.72nm at 300°C annealing temp to 122.0nm at 600°C and surface roughness and grain size rate increase with increasing annealing temp. Experimental findings indicated that the transmittance of films increases with increasing annealing temp. The viewable region's transmittance was 88% at 500°C. In this work, the color coordinates of copper oxide were determined. Three critical color attributes were measured utilizing CIE1931 technology to monitor color values: brightness, color purity, and dominant wavelength. The findings illustrated that the color purity and the dominant wavelength decrease with increasing annealing temp, and these values ranged between (0.7-0.51) and (563-556), respectively, when the temp increased from 300°C to 500°C, in contrast to the brightness values, which increased with increasing annealing temps.