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Polycrystalline Cd1−xZnxTe films were grown on glass substrates over the full range of compositions (0 < x < 1) by metal–organic chemical vapour deposition at 480 °C. The films (∼5 µm thick) showed uniform texture oriented along the ⟨1 1 1⟩ direction, perpendicular to the substrate, independent of the film composition. The dependence of the lattice parameter of cubic Cd1−xZnxTe on the composition followed Vegard's law. The thick Cd1−xZnxTe films were shown to be of a single phase and structurally stable. The average grain size in the thick films was in the range 3–5 µm. The dominant imperfections in the films were twins (mostly Σ = 3) and dislocations. The x-ray diffraction (XRD) FWHM parameter reached a maximum at x = 0.5. Transmission electron microscopy (TEM) in situ heating in the range 200–400 °C caused plastic deformation in the grains without causing ordering effects. Optical absorption and low-temperature photoluminescence measurements confirmed the XRD and TEM results.

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Thin films (50-200 nm) of SnO 2 TiO 2 were deposited on SiO 2 /(001)Si substrates by RF-sputtering and by molecular beam before they were annealed in vacuum at 200-900°C. In-situ TEM, XRD, SEM, Raman and IR-spectroscopy were used to analyze the structure transformations in the SnO 2 TiO 2 films. In the as-deposited state, the films are amorphous. They crystallize at higher temperatures (starting at about 500°C) forming nanosized grains. The problem of the spinodal decomposition in the SnO 2 TiO 2 system observed earlier at high temperatures is discussed also for low-temperature processing. The stoichiometry of the films of both groups (reactive ion sputtered and high-vacuum e-gun sputtered) is being compared.

A brief report on experimental and theoretical studies of the kinetics of the laser-induced crystallization ͑LIC͒ in undoped amorphous hydrogenated silicon is presented. It is shown that the LIC occurs at a substantially lower temperature and occurs at this temperature much faster compared to the thermal crystallization in a furnace. A nanoscopic kinetic electron-related model of the LIC is presented. The model explains the experimental observations as the integral effect of a huge amount of nanoscale picosecond atomic and electronic reconstructions leading to more stable material states which are generated by electron-assisted short-lived ͑picosecond͒ large energy fluctuations in nanometer material regions. © 2002 American Institute of Physics. ͓DOI: 10.1063/1.1516875͔The laser-induced crystallization ͑LIC͒ of hydrogenated silicon (a-Si:H) has a considerable potential for technological applications to high-performance thin-film transistors and other devices. [1][2][3] That is why the understanding of the LIC mechanism and ways to control the LIC of a-Si:H are of significant practical importance. However, the LIC kinetic mechanisms are still not clear in spite of extensive studies and impressive achievements in the field. In this letter, we present a brief report on the results of recent experimental studies of the LIC in low-temperature undoped a-Si:H films and on a kinetic electron-related LIC model. This model predicts the main expected observations and suggests an explanation of experimental results, as we will see next. The proposed model is an extension to LIC of our nanoscopic kinetic models successfully applied to a broad range of processes taking place in various amorphous and crystalline material;4 -14 many of these results have been summarized in Refs. 6 and 7 and reviewed in Ref. 8. These applications include continuous wave laser-induced structural changes in a-Si:H ͑and other amorphous materials͒, 4,6 the thermal crystallization in a-Si:H 5,6 and amorphous silicon (a-Si), 9 as well as the thermal recrystallization and intermixing in Si/Ge superlattices of nanometer periods disordered by ion implantation. 10 The aforementioned structural changes in metastable amorphous materials include the following phenomena which can also be extended to the LIC kinetics in a-Si:H. First, the observed crystallization includes a huge number of diffusionlike hoppings of Si atoms toward more ordered states related to a lower free energy. In the course of the crystallization, each of the Si atoms involved experiences on the average A ϭ5 -10 hoppings.Second, the hoppings of Si atoms are generated by nanoscale short-lived ͑picosecond͒ large energy fluctuations ͑SLEFs͒ of atomic particles up to their peak thermal energy ͑per atom͒ ip у⌬EӷkT ͑T is temperature and k is the Boltzmann constant͒. The SLEF-generated hyperthermal fluctuating atoms are able to overcome the energy barriers ⌬E ӷkT and perform diffusionlike jumps into more ordered positions related to a lower free energy. 4 -6,9,11,12 Third, SLEFs and SLEF-induced...