Titanium dioxide (TiO2) thin films were deposited by RF magnetron sputtering on glass and silicon substrates at different substrate temperatures (20, 100, 200 and 300 °C). The structural and morphological characteristics of the films were investigated by X ray Diffractometry (XRD) and Atomic Force Microscopy (AFM) while the optical properties of the films were studied by optical spectroscopy. It was shown that at room temperature, TiO2 films grown on glass were amorphous following the substrate structure. At higher temperatures, XRD detected only a nanocrystalline rutile TiO2 structure. This indicated that the transition temperature toward the most stable TiO2 phase was obtained from 100 °C and the crystallinity was enhanced at higher growth temperature. For TiO2 films grown on Si substrates, only a nanocrystalline anatase TiO2 structure was obtained at room temperature. At higher temperatures, we noticed the appearance of other secondary phases related to rutile, anatase and brookite structures. From AFM images, we noticed that at room temperature, the films were porous. With increasing the temperature, the structure of the films became crystallized showing a columnar structure. Film growth and structural properties were discussed in terms of the Thornton model. From optical analysis, the films were transparent with an indirect band gap and a refraction index which reached 3.09 eV and 2.7, respectively. The reflectance and transmittance spectra showed, not only that there was a little translation from UVB to UVA and near‐visible range, but also a decrease of reflection with a temperature increase indicating that the films could be used as anti‐reflection coatings. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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Nowadays, CAN bus, as a well-known, field bus, reaches its limits when dealing with sophisticated embedded systems that require reliability and high-speed data transfer. Switched fabric can be a fast and reliable hardware solution for existing CAN-bus limits. In fact, it allows multiple packets to be transferred simultaneously ensuring sufficient bandwidth. To resolve this problem when keeping the use of CAN protocol, we remove the CAN access technique module from an existing VHDL implementation of a CAN controller component and we replace it by a crossbar switched fabric, implemented in VHDL also. In this paper, we designed a Crossbar switched fabric CAN based on VHDL modules and we simulated it under ModelSim tools and we give of proof-of-concept of a CAN controller based on crossbar switched fabric.

Titanium dioxide (TiO2) thin films were prepared by RF magnetron sputtering technique at an argon flow rate of 4.9 sccm and room temperature during 4 h. These films were deposited on pyrex substrates with an RF power of 300 W and annealed at different temperatures (500, 600, 700 and 800 °C). The optical and structural properties were studied by spectrophotometry and X ray Diffractometry respectively. The obtained results show an amorphous structure for the unheated TiO2 films and an apparition of an anatase phase after the annealing process. The transmittance is increased with an annealing of 500°C from 45 to 80 % in the visible and near-infrared regions. The direct band gap, refractive index, extinction coefficient and grain size were investigated. The reflection in the visible range for a silicon (Si(p)) substrate covered by TiO2 thin films is decreased to be about 20%. The results of this work suggest that the variation of the annealing temperature allow the control of the physical properties of TiO2 thin films as antireflective coating for silicon solar cells.