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1. Correlation of luminescence measurements to the structural characterization of Pr3+-doped HfSiOx

Author

Etienne Talbot, Larysa Khomenkova, Rémi Demoulin, Celia Castro, Christophe Labbé, Fabrice Gourbilleau, Philippe Pareige, Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Caen Normandie (UNICAEN), V.E. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine (NASU), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Photoluminescence, Materials science, Annealing (metallurgy), Cathodoluminescence, Biophysics, Analytical chemistry, 02 engineering and technology, Atom probe, 010402 general chemistry, 01 natural sciences, Biochemistry, law.invention, law, Rare-earth, Phase transition, Structural properties, General Chemistry, Sputter deposition, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Amorphous solid, Hafnium silicates, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Orthorhombic crystal system, 0210 nano-technology, Luminescence
Abstract

International audience; Luminescence and structural properties of Pr3+ doped HfSiOx thin layer elaborated by magnetron sputtering have been investigated as a function of the annealing temperature. The emission properties of Pr3+ ions were studied using photoluminescence (PL) and cathodoluminescence (CL) spectroscopies. Phase separation between amor- phous SiO2 and crystallized HfO2 nano-grains occurring in the HfSiOx matrix has been investigated by atom probe tomography and transmission electron microscopy with particular consideration for the Pr distribution. Both PL and CL measurements evidenced a strong emission originating from Pr3+ ions in the visible range for an annealing temperature higher than 950◦C. At 950◦C, Pr3+ ions are clearly located in HfO2 nano-grains of cubic structure. Regarding PL, no significant changes are observed between 950◦C and 1050◦C. However, CL mea- surements revealed new emission peaks in the infrared range after an annealing at 1050◦C, corresponding to the appearance of a new orthorhombic crystalline structure of HfO2 nano-grains in the thin layer. The CL signal evolution as a function of the annealing treatment is discussed in regard to the evolution of structural properties.

Published
2021
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2. Evidence of Mg segregation to threading dislocation in normally-off GaN-HEMT

Author

Sébastien Duguay, Andres Echeverri, Celia Castro, Olivier Latry, Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), and Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, business.industry, Doping, Normally off, 02 engineering and technology, Substrate (electronics), High-electron-mobility transistor, Atom probe, 021001 nanoscience & nanotechnology, Computer Science Applications, law.invention, [SPI.MAT]Engineering Sciences [physics]/Materials, law, Threading (manufacturing), Optoelectronics, Electrical and Electronic Engineering, Diffusion (business), Dislocation, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 0210 nano-technology, business, ComputingMilieux_MISCELLANEOUS
Abstract

In this article, the segregation of Mg to threading dislocation is demonstrated in a commercial normally-off GaN High Electron Mobility Transistor using atom probe tomography. The diffusion of Mg from a doped p-type GaN gate through the AlGaN buffer to the GaN substrate is demonstrated.

Published
2019
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3. Influence of RbF post deposition treatment on heterojunction and grain boundaries in high efficient (21.1%) Cu(In,Ga)Se2 solar cells

Author

Mohit Raghuwanshi, Celia Castro, Philippe Pareige, Dimitrios Hariskos, Wolfram Witte, Arantxa Vilalta-Clemente, Emmanuel Cadel, Philip L. Jackson, Sébastien Duguay, Groupe de physique des matériaux (GPM), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Rheinisch-Westfälische Technische Hochschule Aachen University (RWTH), Zentrum fur Sonnenenergie-und Wasserstoff-Forschung (ZSW), Zentrum fur Sonnenenergie-und Wasserstoff-Forschung, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), and RWTH Aachen University

Subjects
Materials science, Analytical chemistry, 02 engineering and technology, Atom probe, 010402 general chemistry, 01 natural sciences, law.invention, [SPI.MAT]Engineering Sciences [physics]/Materials, chemistry.chemical_compound, law, General Materials Science, Electrical and Electronic Engineering, Rubidium fluoride, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, ComputingMilieux_MISCELLANEOUS, Renewable Energy, Sustainability and the Environment, Chalcopyrite, Heterojunction, 021001 nanoscience & nanotechnology, Copper indium gallium selenide solar cells, 0104 chemical sciences, chemistry, Transmission electron microscopy, visual_art, visual_art.visual_art_medium, Grain boundary, 0210 nano-technology, Deposition (chemistry)
Abstract

Post deposition treatments (PDT) by alkali fluorides applied to chalcopyrite-based absorbers have produced record efficiencies in thin-film solar devices in the past few years and recently the efficiency of 22.6% was achieved with Cu(In,Ga)Se2 (CIGS) using rubidium fluoride (RbF) PDT. However, the effects of RbF-PDT towards changes in its interfacial and grain boundary (GB) properties are still not fully understood. In this work, cells with efficiency higher than 21% are investigated by combination of atom probe tomography (APT) and transmission electron microscopy (TEM) to show how changes in GB and interface chemistry may facilitate high efficiencies. APT studies, carried out at the interface between CIGS absorber and solution-grown CdS buffer layer, show In enrichment and Cu depletion along with traces of Rb. Our APT studies reveal higher amounts of Rb (1.5 at. %) and lower amounts of Na and K (

Published
2019
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4. Reverse Monte Carlo reconstruction algorithm for discrete electron tomography based on HAADF-STEM atom counting

Author

F. Moyon, Celia Castro, M. D. Robertson, Williams Lefebvre, A. Etienne, and D. Hernández-Maldonado

Subjects
010302 applied physics, Physics, Histology, Monte Carlo method, Reconstruction algorithm, 02 engineering and technology, Reverse Monte Carlo, 021001 nanoscience & nanotechnology, 01 natural sciences, Pathology and Forensic Medicine, Computational physics, law.invention, Electron tomography, Transmission (telecommunications), law, 0103 physical sciences, Atom, Particle, Atomic physics, Electron microscope, 0210 nano-technology
Abstract

Summary In this paper, we propose an algorithm to obtain a three-dimensional reconstruction of a single nanoparticle based on the method of atom counting. The location of atoms in three dimensions has been successfully performed using simulations of high-angle-annular-dark-field images from only three zone-axis projections, [110], [310] and [211], for a face-centred cubic particle. These three orientations are typically accessible by low-tilt holders often used in high-performance scanning transmission electron microscopes.

Published
2016
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5. Origin of Pr 3+ luminescence in hafnium silicate films: combined atom probe tomography and TEM investigations

Author

Georges Beainy, Celia Castro, Christophe Labbé, Fabrice Gourbilleau, Larysa Khomenkova, Rémi Demoulin, Philippe Pareige, Etienne Talbot, Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, phase transformation, Biomedical Engineering, chemistry.chemical_element, Bioengineering, 02 engineering and technology, Atom probe, 010402 general chemistry, 01 natural sciences, law.invention, [SPI.MAT]Engineering Sciences [physics]/Materials, [PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph], chemistry.chemical_compound, law, General Materials Science, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, hafnium silicates, rare-earth ions, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, Silicate, 0104 chemical sciences, Hafnium, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, chemistry, atom probe tomography, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Physical chemistry, photoluminescence, 0210 nano-technology, Luminescence
Abstract

International audience; Origin of Pr 3+ luminescence in hafnium silicate films: combined atom probe tomography and TEM investigations To cite this article: Rémi Demoulin et al 2018 Nano Futures 2 035005 View the article online for updates and enhancements. Related content Thermal stability of high-k Si-rich HfO2 layers grown by RF magnetron sputtering L Khomenkova, X Portier, J Cardin et al.-High-k Hf-based layers grown by RF magnetron sputtering L Khomenkova, C Dufour, P-E Coulon et al.-XRD and EXAFS studies on the structure of Er3+-doped SiO2–HfO2 glass-ceramic waveguides: Er3+-activated HfO2 Abstract Structural, chemical, and luminescence properties of Pr 3+-doped HfSiO x layers fabricated by radio-frequency magnetron sputtering were examined as a function of annealing temperature. Phase separation between SiO 2 and HfO 2 as well as the location of Pr 3+ dopants were investigated using atom probe tomography and transmission electron microscopy while optical properties of Pr 3+ ions were studied using photoluminescence measurements. As a result, (i) we evidenced the location of the Pr 3+ dopants in the HfO 2 phase while the SiO 2 phase was discovered to be free of these dopants, (ii) the HfO 2 phase was identified to crystallize in the cubic phase until 1050 °C annealing, (iii) no Pr clusters were detected as function of annealing, and (iv) luminescence properties were discussed in regard to the location of Pr in the HfO 2 cubic phase.

Published
2018
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6. First transparent oxide ion conducting ceramics synthesized by full crystallization from glass

Author

Celia Castro, Cécile Genevois, Ling Bing Kong, Alberto José Fernández Carrión, Dominique Thiaudière, Guy Matzen, Marina Boyer, Denis Pelloquin, Xiaoyan Yang, Emmanuelle Suard, Emmanuel Véron, Mathieu Allix, Louis Hennet, Quanchao Wang, Xiaojun Kuang, Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Guilin University of Electronic Technology, Institut Laue-Langevin (ILL), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Groupe de physique des matériaux (GPM), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de cristallographie et sciences des matériaux (CRISMAT), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Nanyang Technological University [Singapour], College of materials science and engineering, Guilin University of Technology, ILL, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université d'Orléans (UO)

Subjects
Materials science, Oxide, 02 engineering and technology, Conductivity, engineering.material, 010402 general chemistry, 01 natural sciences, law.invention, chemistry.chemical_compound, law, Phase (matter), General Materials Science, Ceramic, Crystallization, ComputingMilieux_MISCELLANEOUS, Birefringence, Renewable Energy, Sustainability and the Environment, Melilite, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical engineering, chemistry, visual_art, visual_art.visual_art_medium, engineering, Grain boundary, 0210 nano-technology
Abstract

International audience; We propose here to use full crystallization from glass as an innovative process to elaborate completely dense transparent oxide conductors. This is demonstrated in the case of new non-stoichiometric Ln1+xSr1−xGa3O7+δ (Ln = Eu, Gd or Tb) melilite ceramics which show bulk conductivity greater than 0.02 S cm−1 at 500 °C. Full crystallization from glass is used here as an alternative method to conventional solid state synthesis in order to elaborate new crystalline phases, i.e. melilite compositions with small rare earth elements, which could not be synthesized by a solid state reaction. The materials are stable up to 800 °C under cycled conductivity measurement conditions. Moreover, as melilite compositions show similar glass and crystalline phase densities, the process can produce fully dense ceramics with thin grain boundaries. Coupled to the limited birefringence of the melilite structure, such materials retain some of the glass transparency during crystallization, leading to the first transparent oxide ion conducting ceramics. This work may open a way to a new class of fully dense, and possibly transparent, solid state electrolytes.

Published
2018
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7. Nature of the Catalyst Particles in CCVD Synthesis of Multiwalled Carbon Nanotubes Revealed by the Cooling Step Study

Author

Mathieu Pinault, Pascale Launois, Celia Castro, Julien Cambedouzou, Vasile Heresanu, Odile Stéphan, Cécile Reynaud, Martine Mayne-L’Hermite, Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Quenching, Materials science, Electron energy loss spectroscopy, Nanotechnology, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Catalysis, law.invention, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Condensed Matter::Materials Science, Chemical state, General Energy, Electron diffraction, Chemical engineering, law, Carbon nanotube supported catalyst, Physical and Theoretical Chemistry, 0210 nano-technology, Pyrolysis
Abstract

The true chemical nature and physical state of the catalyst particles in Catalytic Chemical Vapor Deposition (CCVD) synthesis of carbon nanotubes are the subject of intense discussions, as it is one of the keys to understand their growth mechanisms. The CCVD method considered in this article involves pyrolysis of mixed liquid aerosols and leads to the synthesis of large carpets of multiwalled nanotubes (MWNTs) partially filled with iron-based materials. The experimental approach consists in studying the influence of the cooling procedure applied at the end of the synthesis. Both slow standard cooling or quenching were performed, and the structure and chemical state of the iron-based particles were compared through complementary local and global investigations involving X-ray diffraction, electron microscopy, electron diffraction, as well as electron energy loss spectroscopy. We clearly demonstrate that iron-based catalyst particles are carbon-rich and oxygen-free in quenched samples, and that they oxidize during the slow cooling step. It is inferred that they are very probably molten supersaturated carbon-metal particles during the NT growth.

Published
2008
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8. Evolution of shape, size, and areal density of a single plane of Si nanocrystals embedded in SiO2 matrix studied by atom probe tomography

Author

Bin Han, Gerard Ben Assayag, Celia Castro, Michele Perego, Yasuyoshi Nagai, Yasuo Shimizu, Koji Inoue, Gabriele Seguini, Elisa Arduca, Sylvie Schamm-Chardon, WPI Advanced Institute for Materials Research (WPI-AIMR), Tohoku University [Sendai], Laboratorio MDM (IMM-CNR), Consiglio Nazionale delle Ricerche [Roma] (CNR), Matériaux et dispositifs pour l'Electronique et le Magnétisme (CEMES-MEM), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Silicon, Materials science, E beam evaporation, Annealing (metallurgy), General Chemical Engineering, Layer thickness, Analytical chemistry, chemistry.chemical_element, High resolution transmission electron microscopy, 02 engineering and technology, Atom probe, Multilayer structures, 01 natural sciences, law.invention, Areal densities, law, 0103 physical sciences, Energy filtered transmission electron microscopy, Area density, High-resolution transmission electron microscopy, 010302 applied physics, [PHYS]Physics [physics], Si nanocrystal, General Chemistry, 021001 nanoscience & nanotechnology, Nanocrystals, Atom probe tomography, chemistry, Nanocrystal, Transmission electron microscopy, Probes, Si (100) substrate, 0210 nano-technology
Abstract

cited By 4; International audience; Single planes of Si nanocrystals (NCs) embedded in a SiO2 matrix were synthesized by annealing SiO2/SiO/SiO2 multilayer structures deposited on Si (100) substrates by e-beam evaporation. The dependence of the shape, size, and areal density of Si NCs on the thickness of the initial SiO layer was investigated using atom probe tomography and validated by energy filtered transmission electron microscopy. Three kinds of samples were prepared with SiO layer thicknesses of 4, 6, and 10 nm. The size of Si NCs enlarged with increasing SiO layer thickness. The shape of Si NCs was mainly extended spheroid in all three kinds of samples. In the sample with the 4 nm-thick SiO layer, the Si NCs were more prolate than those in the other two samples. Moreover, many rod-shaped Si NCs appeared in the sample with the 10 nm-thick SiO layer. These rod-shaped Si NCs were found to be connected by small Si NCs. The areal densities of Si NCs were in the order of 1012 NCs per cm2 in all samples. © 2016 The Royal Society of Chemistry.

Published
2016
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9. Structural and optical study of Ce segregation in Ce-doped SiO 1.5 thin films

Author

Hervé Rinnert, Jennifer Weimmerskirch-Aubatin, Etienne Talbot, Michel Vergnat, Georges Beainy, Celia Castro, Philippe Pareige, Mathieu Stoffel, Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), and Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010302 applied physics, Photoluminescence, Materials science, Silicon, Annealing (metallurgy), Inorganic chemistry, Doping, Analytical chemistry, General Physics and Astronomy, chemistry.chemical_element, 02 engineering and technology, Atom probe, 021001 nanoscience & nanotechnology, 01 natural sciences, law.invention, Cerium, chemistry, law, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Thin film, 0210 nano-technology, Luminescence
Abstract

International audience; Cerium doped SiO 1.5 thin films fabricated by evaporation and containing silicon nanocrystals were investigated by atom probe tomography. The effect of post-growth annealing treatment has been systematically studied to correlate the structural properties obtained by atom probe tomography to the optical properties measured by photoluminescence spectroscopy. The atom probe results demonstrated the formation of Ce-Si rich clusters upon annealing at 900 C which leads to a drastic decrease of the Ce-related luminescence. At 1100 C, pure Si nanocrystals and optically active cerium silicate compounds are formed. Consequently, the Ce-related luminescence is found to reappear at this temperature while no Si-nanocrystal related luminescence is observed for films containing more than 3% Ce. V C 2015 AIP Publishing LLC. [http://dx.

Published
2015
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10. Atomic characterization of Au clusters in vapor-liquid-solid grown silicon nanowires

Author

Didier Stiévenard, Bruno Grandidier, Wanghua Chen, Celia Castro, Tao Xu, Philippe Pareige, Pere Roca i Cabarrocas, Laboratoire de physique des interfaces et des couches minces [Palaiseau] (LPICM), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), University of Connecticut (UCONN), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), and Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Microscope, Scanning electron microscope, Nanowire, Analytical chemistry, General Physics and Astronomy, 02 engineering and technology, Atom probe, 01 natural sciences, Focused ion beam, law.invention, Condensed Matter::Materials Science, law, 0103 physical sciences, Scanning transmission electron microscopy, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], ComputingMilieux_MISCELLANEOUS, 010302 applied physics, business.industry, 021001 nanoscience & nanotechnology, Transmission electron microscopy, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Scanning tunneling microscope, 0210 nano-technology, business
Abstract

By correlating atom probe tomography with other conventional microscope techniques (scanning electron microscope, scanning transmission electron microscope, and scanning tunneling microscopy), the distribution and composition of Au clusters in individual vapor-liquid-solid grown Si nanowires is investigated. Taking advantage of the characteristics of atom probe tomography, we have developed a sample preparation method by inclining the sample at certain angle to characterize the nanowire sidewall without using focused ion beam. With three-dimensional atomic scale reconstruction, we provide direct evidence of Au clusters tending to remain on the nanowire sidewall rather than being incorporated into the Si nanowires. Based on the composition measurement of Au clusters (28% ± 1%), we have demonstrated the supersaturation of Si atoms in Au clusters, which supports the hypothesis that Au clusters are formed simultaneously during nanowire growth rather than during the cooling process.

Published
2015
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11. Silicon crystallization in nanodot arrays organized by block copolymer lithography

Author

Celia Castro, Gabriele Seguini, Michele Perego, A Andreozzi, Sylvie Schamm-Chardon, Gérard Benassayag, Laboratorio MDM (IMM-CNR), Consiglio Nazionale delle Ricerche [Roma] (CNR), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Matériaux et dispositifs pour l'Electronique et le Magnétisme (CEMES-MEM), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), NanoSci-E+ - ANR-08-NSCI-003: NANOBLOCK, ANR-08-NSCI-0003,NANO-BLOCK(2008), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse)

Subjects
Amorphous silicon, electron beam, Nanoporous templates, synthesis, crystallization, Silicon oxides, law.invention, evaporation, high temperature, chemistry.chemical_compound, law, Electron beam evaporation, General Materials Science, Crystallization, [PHYS]Physics [physics], density, Nanoporous, Lateral distributions, Block copolymer lithography, quantum dot, Self-assembly, Nanostructured materials, Self assembly, Condensed Matter Physics, Block copolymers, Atomic and Molecular Physics, and Optics, Nanocrystals, unclassified drug, Si nanocrystals, silicon nanodot, Transmission electron microscopy, Modeling and Simulation, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Nanodot, Specific substrates, High-temperature annealing, Materials science, E beam evaporation, Silicon, Nanolithography, chemistry.chemical_element, Bioengineering, Nanotechnology, film, Electron beam physical vapor deposition, Article, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Si nanocrystal, copolymer, silicon, General Chemistry, Amorphous solid, chemistry, Chemical engineering, TEM, polystyrene b polymethylmethacrylate block copolymer, E-beam evaporation, Amorphous films
Abstract

cited By 2; International audience; Asymmetric polystyrene-b-polymethylmethacrylate (PS-b-PMMA) block copolymers are used to fabricate nanoporous PS templates with different pore diameter depending on the specific substrate neutralization protocol. The resulting polymeric templates are used as masks for the subsequent deposition of a thin (h = 5 nm) amorphous Si layer by electron beam evaporation. After removal of the polymeric film and of the silicon excess, well-defined hexagonally packed amorphous Si nanodots are formed on the substrate. Their average diameter (d

Published
2014
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12. The role of hydrogen in the aerosol-assisted chemical vapor deposition process in producing thin and densely packed vertically aligned carbon nanotubes

Author

Celia Castro, Mathieu Pinault, Martine Mayne-L’Hermite, Dominique Porterat, Cécile Reynaud, Laboratoire Francis PERRIN (LFP - URA 2453), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Hydrogen, Nucleation, Nanoparticle, chemistry.chemical_element, Nanotechnology, 02 engineering and technology, Chemical vapor deposition, Carbon nanotube, 010402 general chemistry, 7. Clean energy, 01 natural sciences, law.invention, Catalysis, chemistry.chemical_compound, law, General Materials Science, Thermal decomposition, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Ferrocene, chemistry, Chemical engineering, 0210 nano-technology
Abstract

International audience; Aerosol-assisted catalytic chemical vapor deposition (CCVD) is an efficient single-step process to synthesize vertically aligned carbon nanotube (VACNT) arrays from ferrocene and toluene precursors. While no promoters are needed, adding hydrogen to the carrier gas assists the process. In order to understand the role of hydrogen, we performed syntheses at 850 and 800 °C. The product distribution along the length of the reactor was analyzed by electron microscopy to follow the effect of the hydrogen, as well as the characteristics of the CNT and catalyst nanoparticles. Increasing the hydrogen content shifts the CNT growth towards the furnace entrance and strongly reduces the CNT diameters, while the CNT number density increases. Hydrogen demonstrably affects the gas phase phenomena by lowering the decomposition temperature of ferrocene and increasing the nucleation site density of the catalytic nanoparticles. The yield under hydrogen remains reasonable in the aerosol-assisted CCVD process, and is even improved at 800 °C. Hydrogen content appears to be an interesting parameter to control the characteristics of vertically aligned CNT.

Published
2013
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13. Dynamics of catalyst particle formation and multi-walled carbon nanotube growth in aerosol-assisted catalytic chemical vapor deposition

Author

Celia Castro, Cécile Reynaud, Nedjma Bendiab, Dominique Porterat, Mathieu Pinault, S. Coste-Leconte, Martine Mayne-L’Hermite, Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Systèmes hybrides de basse dimensionnalité (HYBRID), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Systèmes hybrides de basse dimensionnalité (NEEL - HYBRID), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)

Subjects
inorganic chemicals, Nanotube, Vapor pressure, Nanoparticle, chemistry.chemical_element, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, 7. Clean energy, 01 natural sciences, complex mixtures, Catalysis, law.invention, law, Organic chemistry, General Materials Science, technology, industry, and agriculture, General Chemistry, 021001 nanoscience & nanotechnology, equipment and supplies, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Chemical engineering, chemistry, Particle, Carbon nanotube supported catalyst, 0210 nano-technology, Carbon
Abstract

International audience; In aerosol-assisted catalytic chemical vapor deposition (CCVD), the catalyst and carbon precursors are introduced simultaneously in the reactor. Catalyst particles are formed in situ and aligned multi-walled CNTs grow at a high rate. To scale-up the process, it is crucial to understand the chemical transformation of the precursors along the thermal gradient of the reactor, and to correlate nanotube growth with catalyst nanoparticle formation. The products synthesized along a cylindrical CVD reactor from an aerosol composed of ferrocene and toluene, as catalyst and carbon precursor, respectively, were studied. The product surface density and iron content are determined as a function of the location and the iron vapor pressure in the reactor. Samples are analyzed by electron microscopy, X-ray diffraction and Raman spectroscopy. We show the strong influence of the thermal gradient on location and rate of formation of both iron particles and CNTs, and demonstrate that catalyst particles are formed by gas phase homogeneous nucleation with a size which correlates with iron vapor pressure. They are gradually deposited on the reactor walls where nanotubes grow with an efficiency which is varying linearly with catalyst particle density. CNT crystallinity appears very high for a large range of temperature and iron content.

Published
2010
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14. X-ray diffraction study of the evolution of Fe-filled multiwalled carbon nanotubes under pressure

Author

Mathieu Pinault, Celia Castro, Mohamed Mezouar, Martine Mayne-L’Hermite, Julien Cambedouzou, F. Datchi, Vasile Heresanu, Nedjma Bendiab, Pascale Launois, Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Diffraction, Nanotube, Materials science, Nanowire, Nanotechnology, Mechanical properties of carbon nanotubes, 02 engineering and technology, Carbon nanotube, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 01 natural sciences, Electronic, Optical and Magnetic Materials, law.invention, Optical properties of carbon nanotubes, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Condensed Matter::Materials Science, Chemical engineering, Transition metal, law, 0103 physical sciences, X-ray crystallography, 010306 general physics, 0210 nano-technology
Abstract

International audience; We present in situ high pressure X-ray diffraction experiments on multi-walled carbon nanotubes (MWNTs) filled with iron-based nanowires. In addition to our diffraction results, we provide a detailed characterization of our samples in terms of nanotube length, iron contents, nanotube number of walls and radial dimension. Both carbon nanotubes and encapsulated iron-based nanowires were found to be stable under high pressure conditions, in contrast with previous experiments performed on Fe-filled MWNTs where structural transitions of nanotubes and Fe3C nanowires were recorded around 9 GPa. We point out the importance of providing a complete structural characterization of the studied material and we propose an explanation for the contradictory results found in the literature based on different structural characteristics of the samples and on recent results on the non-hydrostaticity of some pressure transmitting media.

Published
2009
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15. Quantitative analysis of doped/undoped ZnO nanomaterials using laser assisted atom probe tomography: Influence of the analysis parameters

Author

Corine Sartel, Lorenzo Mancini, Xavier Portier, Said Hassani, Vincent Sallet, Nooshin Amirifar, Jonathan Houard, Lorenzo Rigutti, Ahmed Ziani, Celia Castro, Emir Zehani, Etienne Talbot, Rodrigue Lardé, Philippe Pareige, Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Groupe d'Etude de la Matière Condensée (GEMAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Caen Normandie (UNICAEN), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, General Physics and Astronomy, Nanotechnology, 02 engineering and technology, Atom probe, 01 natural sciences, law.invention, Nanomaterials, Condensed Matter::Materials Science, law, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Microelectronics, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010302 applied physics, business.industry, Doping, 021001 nanoscience & nanotechnology, Laser, Evaporation (deposition), Semiconductor, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Atom optics, Optoelectronics, 0210 nano-technology, business
Abstract

International audience; In the last decade, atom probe tomography has become a powerful tool to investigate semiconductor and insulator nanomaterials in microelectronics, spintronics, and optoelectronics. In this paper, we report an investigation of zinc oxide nanostructures using atom probe tomography. We observed that the chemical composition of zinc oxide is strongly dependent on the analysis parameters used for atom probe experiments. It was observed that at high laser pulse energies, the electric field at the specimen surface is strongly dependent on the crystallographic directions. This dependence leads to an inhomogeneous field evaporation of the surface atoms, resulting in unreliable measurements. We show that the laser pulse energy has to be well tuned to obtain reliable quantitative chemical composition measurements of undoped and doped ZnO nanomaterials.

Published
2015
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16. Enhanced Transparency through Second Phase Crystallization in BaAl4O7 Scintillating Ceramics

Author

Gaël Patton, Federico Moretti, Guillaume Bonnefont, Salaheddine Alahrache, Celia Castro, Guy Matzen, Cécile Genevois, Marina Boyer, Marina Licheron, Christophe Dujardin, François-Xavier Lefevre, Mathieu Allix, Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO), Laboratoire de cristallographie et sciences des matériaux (CRISMAT), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC), Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Matériaux, ingénierie et science [Villeurbanne] (MATEIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut Lumière Matière [Villeurbanne] (ILM), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), and Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Ceramics, Materials science, Zener pinning, Cost effectiveness, Characterization, 02 engineering and technology, Transparency, 010402 general chemistry, 01 natural sciences, [SPI.MAT]Engineering Sciences [physics]/Materials, law.invention, Optics, law, Transparent ceramic, Fabrication process, Ceramic materials, General Materials Science, Ceramic, Crystallization, Scintillation, Polycrystalline ceramics, Birefringence, Optical properties, Transparent ceramics, business.industry, Nano structuration, Light scattering, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Structural characterization, 0104 chemical sciences, Material birefringence, Scintillation properties, visual_art, visual_art.visual_art_medium, Nanoparticles, Optoelectronics, Grain, Glass, Crystallite, 0210 nano-technology, business, Crystalline phasis
Abstract

cited By 5; International audience; A series of biphasic (100 - z)BaAl4O7-zBaAl2O4 (0 < z ≤ 45) transparent polycrystalline ceramics have been synthesized by full crystallization from glass process. Despite being composed of two birefringent crystalline phases, these new materials exhibit improved transparency compared to the pure BaAl4O7 ceramic recently reported to show remarkable scintillation properties. Multiscale structural characterizations demonstrate that this transparency enhancement can be explained by the presence of nanometer scale BaAl2O4 crystals which crystallize coherently with the BaAl4O7 matrix. We show that the BaAl2O4 nanostructuration limits the BaAl4O7 growth via an original Zener pinning effect, such decreasing light scattering due to the material birefringence. Interestingly, the BaAl4O7 scintillation properties can be retained in these two-phase transparent ceramics. These new materials, showing easier fabrication process, especially glass forming, could further drive the development of cost-effective scintillators. © 2015 American Chemical Society.

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