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The oriented growth of PbLaTiO3 (PLT) and ZnO thin films on (100)InP has been studied, including the influence of buffer oxide layers (CeO2, ZrO2, SrO, YSZ, MgO, and SrTiO3) on the final texture of PLT film obtained. In each case the oxygen pressure, substrate temperature, energy fluence and substrate surface conditions required to obtain a crystalline and preferentially oriented phase have been established. The composition and morphological changes related to the PLT/YSZ/(100)InP heterostructure profile have been studied in order to investigate the processes involved in the growth of these oxides on (100)InP.Se ha estudiado el proceso de depósito mediante ablación con láser de láminas delgadas de PbTiO3 modificado con La (PLT) y ZnO sobre (100)InP. Para el PLT se han depositado láminas intermedias de óxidos dieléctricos (CeO2, ZrO2, SrO, YSZ, MgO, y SrTiO3) necesarias para la protección de la superficie del substrato. En cada caso se han establecido las condiciones experimentales (presión de oxígeno, temperatura del substrato, densidad de energía del pulso láser y limpieza de la superficie del substrato) necesarias para obtener láminas cristalinas con orientación preferente. En la heteroestructura PLT/YSZ/(100)InP se estudian los cambios de composición y morfología a lo largo del perfil de la heteroestructura, a fin de investigar los procesos involucrados en el crecimiento de estos óxidos sobre el (100)InP.

A new generation of carbon based composite coatings, with Cr and Ti as alloying elements and additions of B and/or N, was deposited by the unbalanced magnetron sputtering technique. The coatings were designed to produce a duplex layer with a hard coating of CrTiBCN as the intermediate layer and a carbon based tribological (solid lubricant) hard coating of C/CrTiB as the top layer in one deposition process. Chemical composition, physical properties and tribological behaviour of both the intermediate and the combined duplex layers were investigated for a wide range of temperatures (up to 600 °C). Hobs coated with these films were tested for cutting gears, using dry machining conditions. The test results under real conditions in production showed that this type of coating on hobs outperformed commercial TiN coatings. [Copyright &y& Elsevier]

The interaction of NO with TiO2 (110)-(1 x 2) surface has been studied by X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, Auger electron spectroscopy, and low-energy electron diffraction, with the aim to clarify the role of ordered defects in NO reactivity toward TiO2. The interaction was studied for exposures up to 2000 L. However, the main effects occur already in the first 2 L. The exposure of the surfaces to NO resulted in the healing of defect sites without adsorption of N and low-energy electron diffraction shows that the surface (1 x 2) symmetry is not lost after the NO dose.