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Diffusion of Au and Cu in amorphous germanium was produced by CW Ar laser excitation during furnace heating. Comparison with classical furnace annealing shows a lowering of the crystallization temperature and an increase of the diffusion rate. A transmission electron microscopy study (imaging and electronic diffraction) shows the formation of metastable compounds. The results are analyzed in relationship to the transient sequence of the produced metastable phases.

Amorphous Si and Ge, subject to mechanical contact with Au, Cu and Ni, have been crystallized under external excitation produced by a CW Ar laser combined with furnace annealing. Compared to simple thermal annealing, a lowering of the crystallization temperature and an increase of the diffusion rate of the metallic components have been observed. By TEM we identified some metastable phases of metal-semiconductor compounds.

Zirconium tellurides ZrTex, with x = 3 or 5, are highly interesting because of their quasi-one-dimensional crystal anisotropy and their related unusual electronic properties. To our knowledge, thin films of ZrTe alloys have been grown for the first time by sputtering a binary target using a triode configuration. The morphology of the films and their growth characteristics on various kinds of substrates such as polyimide, optical glass, silicon or molybdenum have been studied by microprobe X-ray and standard X-ray diffraction methods. The substrate temperature appears to play a crucial role on the film composition. As-deposited stoichiometric ZrTe5 thin films present a preferential orientation with respect to the substrate surface, while an annealing procedure is of prime importance to achieve crystallization in ZrTe3-type films. Other analyses such as Auger electron spectroscopy, X-ray photoelectron spectroscopy and extended X-ray absorption edge fine structure reveal the relative instability of these sputtered films, even in air, at room temperature. All results demonstrate the feasibility of preparing films of low dimensional material by the sputtering technique. Reflectivity and conductivity measurements carried out for our first deposits will be discussed in relation to crystal orientation and the nature of the substrate.