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γ- In 2 Se 3 thin film are deposited for various substrate temperatures in the range of 523–673 K. This study shows that at 573 and 673 K the thin films are well crystallized with grains aligned along the c axis. Between these temperatures, a domain of instability appears where the γ-In2Se3 thin films have a randomly orientation and the c-lattice parameter increases. The presence of the metastable phase κ-In2Se3, during the growth, can explain the existence of this domain of instability. The insertion of Zn during the preparation process allows us to stabilize the phase κ at room temperature which confirms our hypothesis that the presence of κ-In2Se3 perturbs the crystallization of γ-In2Se3. The increase of the c-lattice parameter can be explain by the fact that κ-In2Se3 has a larger unit cell than γ-In2Se3 or by a competition during the growth between the grains of both phases which could generate constraints along the c axis. During the cooling, the κ phase disappears in favor of the γ phase.

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ZnO thin films deposited by chemical bath deposition (CBD) have been studied using x-ray diffraction, scanning electron microscopy, electron microprobe analysis and electrical measurements. The optimum CBD conditions for achieving structured, but adherent, ZnO films are as follows. Zinc acetate (0.0188 mol l−1) and ethylenediamine (0.03 mol l−1) are mixed. The pH of the bath is raised by addition of a base (0.5 mol l−1, NaOH). The solution is maintained at a temperature between 60 °C and 65 ° C, while the bath is continuously stirred. We proceeded to anneal in room air for 30 min at 300 °C and under vacuum for 2 h at 300 °C. All the films obtained are nearly stoichiometric ZnO films crystallized in the usual hexagonal structure. As expected the films are rough and porous. The main difference between the two ZnO film families is their conductivity. The conductivity of the films annealed under vacuum is five orders of magnitude higher than that of those annealed in room air.