Influence of the substrate temperature on the structure of Ge containing thin films produced by ArF laser induced chemical vapour deposition

Ge, SiGe and SiGeC films were grown on Si(1 0 0) and Corning glass (7059) substrates by ArF-excimer laser induced chemical vapour deposition in parallel configuration. Different substrates temperatures ranging from 180 to 400 8C, for a fixed reactant gas composition, were used at constant total pressure and laser power. The analysis of the films showed the existence of a relationship between the substrate temperature and the deposition rate as well as to the film properties. A comparison among the pure, binary and ternary Ge containing system was performed to study the influence of the presence of different gases in the reactant mixture. Structural properties of the deposited films were investigated by Raman and Fourier transform infrared spectroscopy. Their surface morphology was evaluated by scanning electron microscopy and atomic force microscopy (AFM). X-ray photoelectron spectroscopy (XPS) revealed the composition of the alloys and X-ray diffraction experiments demonstrated the polycrystallinity of some pure Ge films.