Publications Scientifiques
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Item Speed-up of high accuracy analog test stimulus optimization(1999) Khouas, Abdelhakim; Derieux, AnneAnalog integrated circuit testing and diagnosis is a very challenging problem. The inaccuracy of measurements, the infinite domain of possible values and the parameter deviations are among the major difficulties. During the process of optimizing production tests, Monte Carlo simulation is often needed due to parameter variations, but because of its...Item Methodology for Fast and Accurate Analog Production Test(1999) Khouas, Abdelhakim; Derieux, AnneThis paper describes a new technique to reduce the number of simulations required during analog fault simulation. 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. In section I a review of the state of the art.Item Speed-up of High Accurate Analog Test Stimulus(1999) Khouas, Abdelhakim; Derieux, AnneAnalog integrated circuit testing and diagnosis is a very challenging problem. The inaccuracy of measurements, the innite domain of possible values and the parameter deviations are among the major diOEculties. During the process of optimizing production tests, Monte Carlo simulation is often needed due to parameter variations, but because of its expensive computational cost, it becomes the bottleneck of such a process. This paper describes a new technique to reduce the number of simulations required during analog fault simulation. This leads to the optimization of production tests subjected to parameter variations. In section I a review of the state of the art is presented, section II introduces the algorithm and describes the methodology of our approach. The results on CMOS 2-stage opamp and conclusions are given in sections III and IVItem 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 Contact Resistance Determination For Multi-crystalline Silicon Solar Cells By Using Transmission Line Method (TLM)(2008) Tala-Ighil, Razika; Sali, S.; Oussalah, Slimane; Boumaour, Messaoudhe main objective in solar cells realization consists in increasing their performances. The mechanisms of this increase obey specific phenomena of physics. There is necessarily a contact resistance value behind each value of conversion efficiency. The question is how to quantify the contact resistance and what is its behaviour with different temperature profiles and consequently with the conversion efficiency. This work responds to all of these questions. We have taken square multicrystalline silicon wafers of 10 cm sides. These wafers have followed the traditional process steps i.e.: chemistry, diffusion, silicon nitride PECVD deposition and metallization of the front grid with TLM (Transmission Line Method) mask. The TLM measures are obtained using a test bench which includes a four-point prober and an analyzer. The contact resistance is deduced by the plot of the resistance versus the TLM line distance. It represents the R(D2), R(D3), R(D23), R(D4) and R(D34) where D2, D3, D23, D4 and D34 are the TLM distances. The TLM resistance is the half of the intersection of the slope R(D) with the y-axis. A profile of the evolution of the contact resistance versus the screen printing temperature annealing from 650°C to 800°C for the multi-crystalline silicon solar cells has been obtained.Item 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.