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We have studied the epitaxial growth of Pt films on MgO substrates by laser ablation. Depending upon oxygen pressure during deposition, different Pt film textures were observed. Pure (001) films are grown under oxygen (0.1 mbar), while (111) films are formed under high vacuum (<10−6 mbar). By the complementary use of Rutherford backscattering spectrometry in channeling geometry and x-ray diffraction, the crystalline quality was found nearly perfect. Finally multilayered structures with LiCoO2 or LiMn2O4 layer on Pt film on MgO substrates were epitaxially grown by laser ablation. Such oxide films could present interesting properties as insertion compounds in lithium batteries, and we demonstrate that LiMn2O4 could be used for the accurate determination of lithium concentration in solution.

Crystalline erbium(Er)-doped zinc oxide thin films have been grown by pulsed-laser deposition and were analyzed by the complementary use of Rutherford backscattering spectroscopy, x-ray diffraction analysis, atomic force microscopy, and photoluminescence. The composition, structure, and surface morphology of films were studied, as a function of the growth conditions (temperature from 300 °C to 750 °C and oxygen pressure from 10−6 to 0.5 mbar) and Er-doping rate, and were correlated to the emission spectroscopy of Er in the infrared domain. While these studies lead to the determination of optimal conditions for the growth of high crystalline quality films, results of photoluminescence experiments show that the insertion of Er ions in the ZnO matrix does not follow a simple pattern. The Er ions are incorporated from two pathways, one population is found inside the crystallites and another one at the grain boundaries, as a consequence of the differences in valence and ionic radius of Zn and Er.

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During layer-by-layer homoepitaxial growth, both the Reflection High-Energy Electron Diffraction (RHEED) intensity and the x-ray reflection intensity will oscillate, and each complete oscillation indicates the addition of one monolayer of material. However, it is well documented, but not well understood, that the phase of the RHEED oscillations is not constant and thus the maxima in the RHEED intensity oscillations do not necessarily occur at the completion of a layer. We demonstrate this using simultaneous in situ x-ray reflectivity and RHEED during layer-by-layer growth of SrTiO3. We show that we can control the RHEED oscillation phase by changing the pre-growth substrate annealing conditions, changing the RHEED oscillation phase by nearly 180• . In addition, during growth via pulsed laser deposition, the exponential relaxation times between each laser pulse can be used to determine when a layer is complete, independent of the phase of the RHEED oscillation.PACS numbers: 68.47. Gh,61.05.cf,81.15.Fg Thin-film growth changed dramatically more than three decades ago with the discovery of reflection high-energy electron diffraction (RHEED) intensity oscillations.1-3 During RHEED, a high-energy (≈ 10-30 keV) electron beam is fired at grazing incidence onto a growth surface and the intensity of the reflected beam is recorded. With RHEED, the incident electrons only interact with the topmost layer. During 2D monolayerby-monolayer growth, researchers discovered oscillations in the intensity of the reflected RHEED beam, and that the period of the oscillation corresponded to the addition of exactly one monolayer to the film. This discovery led to rapid implementation of RHEED systems for thinfilm growth, although largely restricted to semiconductor growth via molecular beam epitaxy due to the low pressures (< 10 −5 mbar) required to use RHEED. 4,5The landscape changed again nearly two decades ago with the development of high-pressure RHEED systems, allowing RHEED systems to operate at pressures as high as 1 mbar.6-8 Since this discovery, in situ RHEED characterization has become nearly ubiquitous in thinfilm growth systems, and it has been successfully implemented in a variety of growth techniques in addition to molecular beam epitaxy, such as sputtering 9 and pulsed laser deposition (PLD). 10Researchers have worked to understand RHEED intensity oscillations via a variety of different methods. In principle, the complete picture can only be understood using dynamical diffraction theories, 11,12 which often have to be modified for complicated growth conditions (e.g., including variations in the scattering potential 13 or small terrace sizes 14 ). Before resorting to a full model, it often suffices to describe the RHEED intensity oscillations as the interference between two layers via a kinematic scattering approximation, 15,16 though this model can become more complex when multiple layers are included 17 or other diffraction features such as Kikuchi lines are included.18 The other often-used simplification is the step ...

Thin films of anthracene (C14H10) have been grown by matrix-assisted pulsed-laser evaporation. Frozen solutions of 2 wt% anthracene (solute) in ortho-xylene or in chloroform were used as targets and were irradiated by a frequency-quadrupled Nd:YAG laser (266 nm). The deposited films were studied by the complementary use of infrared absorption and photoluminescence emission. The vibrational bands and fluorescence emission of bulk anthracene were clearly identified in the films. This means that the organic molecules were not modified by photochemical reactions during the laser irradiations, despite the strong absorption of anthracene at 266 nm. Among the growth parameters, the laser fluence was found to be critical in order to avoid the fragmentation of the anthracene molecules. The results show that matrix-assisted pulsed-laser evaporation is suitable for growing thin films of organic materials even if they absorb at the irradiating wavelength

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