Surface Morphology Dynamics in ITO Thin Films

Davood Raoufi, Faegh Hosseinpanahi

Department of Physics, University of Bu Ali Sina, Hamedan, Iran.

DOI: 10.4236/jmp.2012.38088                

Abstract

In this study, indium tin oxide (ITO) thin films were prepared by electron beam evaporation method on float glass substrates at room temperature (RT). The surface morphology and dynamic scaling behavior of the films were studied by atomic force microscopy (AFM). It was found that average surface roughness values decreased as the film thickness increased from 100 nm to 350 nm. Fractal geometry and statistical physics techniques have been used to study a variety of irregular films within a common framework of the variance thickness. The Hurst exponent H and growth exponent ? for ITO thin films were determined to be 0.73 ? 0.01 and 0.078, respectively. Based on these results, we suggest that the growth of ITO thin films can be described by the combination of the Edwards-Wilkinson equation and Mullins diffusion equation.

Keywords

ITO; Thin Film; Fractal Analysis; Morphology

Conflicts of Interest

The authors declare no conflicts of interest.

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