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Paviet-Salomon B.,French National Solar Energy Institute | Gall S.,French National Solar Energy Institute | Monna R.,French National Solar Energy Institute | Manuel S.,French National Solar Energy Institute | And 4 more authors.
Energy Procedia | Year: 2011

Phosphorus-doped silicon nitride (SiN(P)) layers have been investigated as dopant sources for laser-induced diffusion. Their optical properties were measured and revealed that reflectivity and refractive index were weakly affected by adding phosphorus (P) and that SiN(P) layers could consequently be used as anti-reflection coatings. These layers were also found to offer efficient surface passivation regardless of the introduced P quantity. Laser doping (LD) and thermal annealing (TA) were then carried out and showed that a wide doping range can be obtained from SiN(P) layers using both driving-in methods. Selective emitter solar cells were then processed using TA to realize the thin emitter and LD to pattern the heavily-doped areas to be metalized. Though cells results need to be further improved, SiN(P) layers appear to be extremely promising as dopant sources for low-thermal budget selective emitter solar cells processing. © 2010 Published by Elsevier Ltd.

Rotaru C.,University of Caen Lower Normandy | Pawlak F.,University of Caen Lower Normandy | Khalfaoui N.,University of Caen Lower Normandy | Dufour C.,University of Caen Lower Normandy | And 5 more authors.
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2012

Vitreous silica thin film (a-SiO 2) and mixed deuterated and hydrogenated amorphous carbon thin film (a-C:D,H), grown or deposited, respectively, on silicon, have been irradiated at GANIL in the MeV/u energy range with ions between C and U in order to reach electronic energy loss between 0.7 and 25 keV/nm. The evolution of Si-O bonds and C-D bonds contents was determined by infrared absorption spectroscopy. Complementary physico-chemical characterization was performed for a-C:D,H using Rutherford backscattering spectrometry (RBS) and elastic recoil detection analysis (ERDA). For a-SiO 2, the band at 1076 cm -1 decreases with the appearance of a band at 1046 cm -1. In the case of the diamond like amorphous carbon, the main effects due to MeV/u ion irradiations are the decrease of sp 3 bonding content and of deuterium relative concentration (D/C atomic ratio) as a function of fluence with the appearance of the sp 1 bond. The cylinder radii in which these physical phenomena are confined can be deduced from a statistical analysis. Using the inelastic thermal spike model (i-TS) these track radii can be described using the electron-phonon mean free path which takes values equal to 3 and 0.9 nm for a-SiO 2 and a-C:D, respectively. Extrapolation to low energy range (∼1 MeV in total or ∼0.02 MeV/u) will be made. © 2011 Elsevier B.V. All rights reserved.

Zaiour A.,Lebanese University | Hamie A.,Lebanese University | Hage-Ali M.,Institute of Electronics of Solids and Systems
Physics Procedia | Year: 2014

Several attempts were made during the last 3 decades to improve the quality of CdTe in order to enhance its efficiency as material for nuclear and photovoltaic devices. These attempts considered the high values of impurity segregation coefficients and the contamination problems due to handling at high temperature. In this study, we prepared three high purity CdTe single crystals with high resistivity. The three starting Te samples were purified through three purification processes: horizontal zone refining, vacuum distillation, and by combining both processes. Purities were characterized, by determining the concentration of 22 impurities by Atomic Absorption (AASGF), for the three kinds of tellurium ingots and the corresponding elaborated CdTe materials. A series of four effective segregation coefficients for metallic impurities: Ag, Al, Cu, and Fe were found in CdTe. Their high values confirmed the difficulty to remove them by the purification processes using the segregation phenomenon. In addition, the low concentration values of impurities in CdTe samples (6N purity) make from our CdTe high quality electronic grade materials. © 2014 Elsevier B.V.

Avasthi D.K.,Inter University Accelerator Center | Mishra Y.K.,Institute for Materials Science | Singh F.,Inter University Accelerator Center | Stoquert J.P.,Institute of Electronics of Solids and Systems
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2010

Swift heavy ions have unique feature of creating ion tracks in insulators of dimension from a few nm to about 10 nm. This particular feature of the swift heavy ions is used to engineer the size and shape of the nanoparticles embedded in silica matrix. On the basis of several experiments, it is evidenced that the embedded nanoparticles either grow in size or reduce in size, if they are smaller than or comparable to the ion track size. The shape transformation from spherical to elongated along the beam direction occurs, when the nanoparticle size is larger than the ion track diameter in silica. The reduction, growth and elongation of Au nanoparticles embedded in silica matrix under swift heavy ion irradiation have been discussed in the frame work of thermal spike model. © 2010 Elsevier B.V. All rights reserved.

Kabir A.,Skikda University | Meftah A.,Skikda University | Stoquert J.P.,Institute of Electronics of Solids and Systems | Toulemonde M.,University of Caen Lower Normandy | Monnet I.,University of Caen Lower Normandy
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2010

In our previous work [15], we have evidenced, using RBS-C, two effects in the aluminium sublattice of sapphire irradiated with 90.3 MeV xenon ions: a partial disorder creation that saturates at ∼40% followed above a threshold fluence by a highly disordered layer appearing behind the surface. In this work, by RBS-C analysis of the oxygen sublattice, we have observed only one regime of partial disorder creation that saturates at ∼60% in tracks of cross-section double of that found for the aluminium sublattice. Complementary analysis by X-ray diffraction shows that the lattice strain increases with the fluence until a maximum is reached about 7.5 × 1012 ions/cm2. For higher fluences, strain decreases first indicating a little stress relaxation in the material and tends afterwards, to remain constant. This stress relaxation is found to be related to the aluminium sublattice high disorder. © 2010 Elsevier B.V. All rights reserved.

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