Fractal analysis of nanostructured silver film surface

Abstract

The electrodeposition method is used to fabricate silver thin films at different thicknesses. The samples then were characterized using X-ray diffraction (XRD) and atomic force microscopy (AFM) techniques. We found that the crystalline structure of the Ag thin films depends on film thickness. The surface morphology and fractal dimension were studied by the AFM image analysis approach. Calculation of standard deviation surface roughness, indicated that it grows as a power-law in time or thickness with the growth exponent of β = 0.67. The average value of Hurst exponent is found to be 0.68 using rescaled range analyses. The results indicate that the morphology and grain size of samples can easily be controlled using different thicknesses. Fractal analysis shows that the fractal dimension of the Ag films increases as the film thickness increases. We proved that the fractal analysis present a useful explanation of the irregularities in the surface film.