Characterization of surface morphology of copper tungsten thin film by surface fractal geometry and resistivity

摘要

Thin films of copper-tungsten (Cu-W) deposited on silicon wafers by magnetron sputtering were characterized by Atomic Force Microscopy (AFM). X-ray diffraction (XRD) and transmission electron microscopy (TEM) and four-point probe method were employed to characterize the microstructure and properties of Cu-W films. Power spectra density (PSD) was used to calculate the fractal dimension of AFM images. The results show that the fractal dimension values increase with the film thickness. A positive correlation between fractal dimension and resistivity of the film was also demonstrated for amorphous films. Changes in the relationship between the resistivity and the fractal dimension are observed for films with possible crystalline structures. (C) 2004 Elsevier B.V. All rights reserved.