Publications Internationales
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Item Analog Fault Detection based on Statistical Analysis(Hal, 2000) Khouas, Abdelhakim; Derieux, AnneIn analog circuits, process variations result in physical parameter variations. Simulated values must then be considered with there tolerance intervals. Consequently, contrarily to digital circuits where the outputs are either '0' or '1' such that we can decide without ambiguity whether a fault is detectable or not, for analog circuits the fault detectability is a vague problem as the fault can either be completely detectable, partially detectable or completely undetectable which makes it very diOEcult to take a decision. In order to solve this decision problem, we have introduced the probability to detect fault (PDF) function which allows to formalize the problem of analog fault detection under parameter variationsItem Optimized Statistical Analog Fault Simulation(2001) Khouas, Abdelhakim; Dessouky, Mohamed; Derieux, AnneA new statistical method for analog fault simulation is presented. The method takes into account process parameter variations and aims to reduce the number of the computational expensive Monte Carlo simulations often required during analog fault simulation. The technique is illustrated by means of a fifth-order low-pass switched-capacitor filterItem The Effect of CO Reducing Atmosphere on the Structural and Optical properties of SnO2: F films Deposited on a Si( N+)/Si(P) solar cell(2006) Zair Tala-Ighil, Razika; Boumaour, Messaoud; Maallemi, Abderrezak; Melhani, kheira; Iratni, A.Item Characterization of Thin Layer SnO 2 /Glass by Neutrons Reflectometry(Scientific.net, 2009) Khelladi, Mohamed Fadel; Izerrouken, M.; Kermadi, Salim; Tala-Ighil, RazikaThe thermal annealing behavior of the SnO2 thin films elaborated by sol-gel method has been studied by the neutrons reflectivity technique. From the fit of the experimental data using Parratt32 software program developed at HMI, Berlin, scattering length density, thickness and roughness are extracted. The obtained results show that the film thickness increases with the increasing annealing temperature, and the roughness is higher at 500 °C. Whereas, approximately, the same scattering length density is obtained after each annealing temperatureItem Preparation and characteristic of low resistive zinc oxide thin films using chemical spray technique for solar cells application(2008) Sali, S.; Boumaour, Messaoud; Tala-Ighil, RazikaIn this paper, we present results concerning undoped and indium-doped zinc oxide (ZnO: In) thin films were grown on glass and Si substrates using the chemical spray technique. The effects of thickness (e), as well as the substrate temperature (Ts), were studied. It was revealed by X-Ray diffraction that the preferred orientation of polycrystals is along C-axis, with hexagonal wurtzite structure. Two important facts were calculated from RBS measurements: the dopant concentration throughout the film and the thickness of the films, it was found that the thickness increase with time of deposition. Under optimum deposition conditions a low resistivity and a high optical transmittance of the order of 2.8 × 10−4 Ω cm and 85 %, respectively, were obtained.Item Effect of H2O Content on Structure and Optical Properties of TiO2 Thin Films Derived by Sol-Gel Dip-Coating Process at Low Temperature(2008) Kermadi, Salim; Agoudjil, N.; Sali, S.; Tala-Ighil, RazikaPure TiO2 thin films were prepared on the glass substrates by sol–gel dip coating technique with titanium (IV) isopropoxide including simultaneously acetylacetone and acetic acid as stabilizing reagents. The effect of the amount of water in the sol on structural and optical properties of TiO2 thin films was investigated. The structural and optical properties of post- sintered films for 1 hour at 500°C in air were investigated By X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–Vis spectroscopy and ellipsometry. The results showed a simultaneous appearance of the rutile and the anatase phases with different rutile / anatase proportions for all samples. The increase of the water content leads to the decrease of rutile / anatase proportion. The crystalline size varies from 7.94 to 24.84 nm for the anatase phase and from 17.70 to 22.31 nm for the rutile phase. The optical measurements showed that the structure was strongly influenced by the water / alcoxides molar ratios. In comparison with the bulk material, the TiO2 thin films prepared by this way exhibit low refractive index in the range of 2.15 and high band gap energy narrowing from 3.88 to 3.95 eV for direct allowed transition and from 3.09 to 3.39 eV for indirect allowed transition according to the cristallinity degree and the rutile /anatase weight fraction.Item Measurement of Square Resistance In Situ of SnO2: F Thin Film With Annealing at High Temperature Under Air(ICTP, 2008) Tahi, Hakim; Boumaour, Messaoud; Tala-Ighil, Razika; Belkaid, M. S.Thin films of fluorine doped tin oxide (SnO2: F), deposited by spray pyrolysis on silicon substrate, were characterized by the method of four points probe in situ during annealing at high temperature under air. The evolution of square resistance (in situ) with the annealing temperature was interpreted in terms of competition between electronic conduction and ionic conduction. A square resistance of 136�/□ is measured before annealing and after annealing at 900°C, the square resistance increases appreciably to reach 40k�/□. This increase is explained by the absorption of oxygen at the films surface and an increase in SiO2 thickness at interface SnO2/SiItem Numerical Simulation of Silicon Based Solar Cells with a Degenerated SnO2:F Window Layer(Cambridge Core, 2007) Tala-Ighil, Razika; Boumaour, MessaoudThe paper presents a numerical simulation of the behaviour of SnO{2}:F/Si(N+)/Si(P) solar cells. The simulation addresses in particular the question of the role of the window layer SnO{2}:F for the device performance. As beginning step, the transparent conductive oxide of SnO{2}:F must be modelled in order to introduce its parameters in simulation codes. Two approaches were employed: one empirical by collecting the experimental data of spray deposited SnO{2}:F while the second one is theoretical by using models of highly degenerate wide band gap semiconductors. The second step consists in injecting the deduced parameters of fluorine doped tin oxide in simulation codes. We use two well-known photovoltaic simulation codes as PC1D and SCAPS 2.5. A comparative study of the results of structures SnO{2}:F/Si(N+)/Si(P) and Si(N+)/Si(P) have been done with a confirmation in enhancing the conversion efficiency by SnO{2}:F window layer addition.Item The Effect of CO Reducing Atmosphere on the Structural and Optical properties of SnO2: F films Deposited on a Si( N+)/Si(P) solar cell(2006) Tala-Ighil, Razika; Boumaour, Messaoud; Maallemi, Abderrezak; Melhani, KheiraItem Analyse de la conception d'un montage d'usinage à l'aide d'éléments modulaires(2007) Zirmi, Said; Paris, Henri; Belaidi, IdirUn montage d'usinage est un outillage indispensable pour fixer la pièce solidement à la bonne position dans l'espace de travail de la machine outil. La conception du montage d'usinage joue un rôle important pour obtenir une pièce usinée de bonne qualité. Nous avons déjà formalisé les connaissances sur les prises de pièce de manière à pouvoir les gérer tout au long du processus de conception de la gamme d'usinage. Maintenant nous nous intéressons à la conception du montage d'usinage de manière à passer du modèle prise de pièce retenu à la solution technologique qui sera utilisée sur le poste de travail. Cet article aborde le problème de conception du montage d'usinage modulaire du point de vue technologique dans sa globalité ; c'est-à-dire le choix et le placement des éléments technologiques en tenant compte de toutes les contraintes de qualité, d'accessibilité et de comportement mécanique du système pièce-montage d'usinage-outil de coupe durant l'usinage