Scaling of size distributions of C60 and C70 fullerene surface islands

Abstract We present experimental data and a theoretical analysis for the size distributions of C 60 and C 70 surface islands deposited onto In-modified Si(111)√3 × √3-Au surface under different conditions. We show that both fullerene islands feature an analytic Vicsek-Family scaling shape where the scaled size distributions are given by a power law times an incomplete beta-function with the required normalization. The power exponent in this distribution corresponds to the fractal shape of two-dimensional islands, confirmed by the experimentally observed morphologies. Quite interestingly, we do not see any significant difference between C 60 and C 70 fullerenes in terms of either scaling parameters or temperature dependence of the diffusion constants. In particular, we deduce the activation energy for surface diffusion of E D  = 140 ± 10 meV for both types of fullerenes.