Cd x Pb 1Ϫx S (0 р x р 1) thin films were prepared on glass substrates using the chemical bath deposition method. The structural, electrical, and photoelectrical properties of the films were investigated, and all were dependent on the x value. For x Ͼ 0.5 ͑high Cd content͒, the films show a poor crystallinity and weak photoconductivity. For x Ͻ 0.5 ͑high Pb content͒, the films exhibit a good crystallinity, with an average size of the crystallites of 100 nm, and good photoconductivity. The threshold voltage of photoconductivity is shifted to lower wavelengths with increasing Cd content. The experimental results point toward possible ternary deposition on some composition ranges ͑near pure PbS or CdS͒; whereas, for the rest, the deposited film is rather a mixture of phases ͓not Cd x Pb 1Ϫx S but (CdS) x (PbS) 1Ϫx ].

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Ge2Sb2Te5 (GST-225) is a chalcogenide material with applications in nonvolatile memories. However, chalcogenide material properties are dependent on the deposition technique. GST-225 thin films were prepared using three deposition methods: magnetron sputtering (MS), pulsed laser deposition (PLD) and a deposition technique that combines MS and PLD, namely MSPLD. In the MSPLD technique, the same bulk target is used for sputtering but also for PLD at the same time. The structural and optical properties of the as-deposited and annealed thin films were characterized by Rutherford backscattering spectrometry, X-ray reflectometry, X-ray diffraction, Raman spectroscopy and spectroscopic ellipsometry. MS has the advantage of easily leading to fully amorphous films and to a single crystalline phase after annealing. MS also produces the highest optical contrast between the as-deposited and annealed films. PLD leads to the best stoichiometric transfer, whereas the annealed MSPLD films have the highest mass density. All the as-deposited films obtained with the three methods have a similar optical bandgap of approximately 0.7 eV, which decreases after annealing, mostly in the case of the MS sample. This study reveals that the properties of GST-225 are significantly influenced by the deposition technique, and the proper method should be selected when targeting a specific application. In particular, for electrical and optical phase change memories, MS is the best suited deposition method.