Fluorine etching on the Si(111)-7x7 surfaces using fluorinated fullerene molecules as a fluorine source has been investigated. At room temperature, adsorbed fluorinated fullerene molecules reacted with the Si(111)-7x7 surface to create a localized distribution of fluorine on the surface. Nanoscale etch pits were created by annealing at 300 o C, due to the adsorption of the fluorine localized around the C 6 0 F x molecules. Annealing at 400 o C resulted in the delocalized fluorine distribution on the surface and healing of the etch pits, due to the enhancement of the diffusion of both the fluorine and silicon atoms. Subsequent annealing at 500 o C led to desorption of SiF 2 reactants formed on the surface. The fluorine diffusion process was found to be an elemental process in the etching because the diffusion of adsorbed fluorines is a key for the formation of the SiF 2 species and their subsequent desorption.