STM STUDY OF FRACTAL SCALING IN EVAPORATED GOLD-FILMS

Fractal characterization of vacuum-evaporated gold films on glass subs trates with thicknesses (h BAR) comprised between 30 and 850 nm is mad e from STM data by using the dynamic scaling approach for surface grow th. The rms roughness (xi) and the scan length (L) obey a xi versus L( alpha) relationship with a depending on hBAR. For hBAR greater-than-or -equal-to 500 nm and L > d(s), the average column diameter, alpha cong ruent-to 1/3 in agreement with the predictions of ballistic deposition models without restructuring. For L < d(s), alpha congruent-to 0.9 ap proaching a euclidean value. The STM method is verified through its ap plication to several computer-generated surfaces, leading to a good ag reement with the theoretical values.