Dynamic scaling, island size distribution, and morphology in the aggregation regime of submonolayer pentacene films

Scaling behavior of the island size distribution through a universal scaling function f(u) is demonstrated for submonolayer pentacene islands in the aggregation regime (0.1<theta<0.5) grown on oxidized silicon surfaces. The distribution of f(u) suggests that four molecules constitute the smallest stable island. The structure factor S(k) of the submonolayer films calculated from AFM micrographs compares well with diffuse x-ray intensities from in situ experiments. The structure factor was decomposed into the contribution from the average island shape and the interisland distribution confirming that a unique characteristic length scale regulates the growth dynamics.