We studied the modifications introduced in the chemical structure of AlF3 films by electron irradiation using Auger electron spectroscopy (AES) and factor analysis (FA). We examined the effects of the current density and energy of the electrons on the film composition. We found that the irradiation produces lower aluminum oxidation states (AlFx with 0<x<3, and Al0), and that while this effect is independent of the electron density it presents a clear dependence on the primary electrons energy. After comparison of experiments on the dose dependence of AlF3 and AlFx reduction, for different energies, with Monte Carlo (MC) simulations, we propose possible mechanisms that lead to electron induced fluorine desorption.