Amorphisation and related structural effects in thin films prepared by ion beam assisted methods

Amorphisation of thin films is a very common phenomenon when their synthesis is assisted by a beam of ions. In this case, X-ray diffraction or related diffraction procedures do not provide a complete description of the phase structure of the films, and alternative methods have to be used to get information about the atom distribution within the lattice. This paper presents some approaches using X-ray absorption and infrared spectroscopy to account for the local structure and other crystallographic effects which may appear in thin films prepared by ion beams. Tin, iron and zirconium oxide thin films, all prepared by ion beam induced CVD, have been selected to show the possibilities of the different characterisation methods. The local distribution of atoms and the evolution of the crystal structure upon annealing are studied as a function of the type of ion species (i.e. O+2 or Ar+) used for the preparation of the films.