Scaling of size distributions of C60 and C70 fullerene surface islands

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)root 3 x root 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. (C) 2017 Elsevier B.V. All rights reserved.