Epitaxial thin-film growth of C-60 on VSe2 studied with scanning tunnelingmicroscopy and x-ray diffraction

The growth of C-60 films On layered IT-VSe2 has been investigated by combin ed scanning tunneling microscopy (STM) and x-ray diffraction. The STM resul ts are discussed in the framework of the diffusion limited aggregation (DLA ) model. Particularly, the crossover from fractal to uniform growth as a fu nction of the aggregated particle concentration is studied and discussed in the context of DLA. The averaged vertical structure is determined by Bragg diffraction and x-ray reflectivity and is explained in conjunction with th e STM results. The epitaxial growth in the (111) direction is confirmed and a homogeneous layer thickness is found. Interfacial roughness and the aver aged dispersion of the film are derived from the data. [S0163-1829(99)10019 -5].