A5014719574- Nanowire Synthesis and Applications
- Geology and Paleoclimatology Research
- Geological and Geochemical Analysis
- Astro and Planetary Science
- Planetary Science and Exploration
- GaN-based semiconductor devices and materials
- Paleontology and Stratigraphy of Fossils
- Geochemistry and Elemental Analysis
- Geomagnetism and Paleomagnetism Studies
- Geological and Geophysical Studies Worldwide
- Photonic and Optical Devices
- Semiconductor materials and devices
- Advancements in Semiconductor Devices and Circuit Design
- Ga2O3 and related materials
- Elasticity and Material Modeling
- Semiconductor materials and interfaces
- Quantum Dots Synthesis And Properties
- Polymer Nanocomposites and Properties
- Semiconductor Quantum Structures and Devices
- Polymer crystallization and properties
- Thermography and Photoacoustic Techniques
- Marine and environmental studies
- Glass properties and applications
- Phase-change materials and chalcogenides
- Metal and Thin Film Mechanics
Institut de Physique de Rennes
2016-2025
Centre National de la Recherche Scientifique
2013-2025
Université de Rennes
2013-2025
Université Paris Cité
2021-2024
Hôpital Cochin
2024
Assistance Publique – Hôpitaux de Paris
2024
Centre Hospitalier Universitaire de Besançon
2024
CEA Grenoble
2014-2023
Université Grenoble Alpes
2013-2023
Institut polytechnique de Grenoble
2013-2023
Two approaches have been compared for the low temperature epitaxy of thick, partially relaxed GeSn layers on top Ge strain buffers. The benefit using step-graded instead constant composition when targeting really high Sn contents (16%, here) was conclusively demonstrated. Digermane (Ge2H6) and tin-tetrachloride (SnCl4) were used as precursors, respectively. growth pressure (100 Torr) F(Ge2H6)/F(SnCl4) mass-flow ratio being constant, it through a lowering that concentration in graded...
With increasing interest in GaN based devices, the control and evaluation of doping are becoming more important. We have studied structural electrical properties a series Si-doped nanowires (NWs) grown by molecular beam epitaxy (MBE) with typical dimension 2-3 μm length 20-200 nm radius. In particular, high resolution energy dispersive X-ray spectroscopy (EDX) has illustrated higher Si incorporation NWs than that two-dimensional (2D) layers segregation at edge NW highest doping. Moreover,...
To fully exploit the potential of semiconducting nanowires for devices, high quality electrical contacts are paramount importance. This work presents a detailed in situ transmission electron microscopy (TEM) study very promising type NW contact where aluminum metal enters germanium nanowire to form an extremely abrupt and clean axial metal-semiconductor interface. We this solid-state reaction between TEM using two different local heating methods. Following interface intrusion Al Ge shows...
Recent advancements in high-resolution spectroscopy analyses within the scanning transmission electron microscope (STEM) have paved way for measuring concentration of chemical species crystalline materials at atomic scale. However, several artifacts complicate direct interpretation experimental data. For instance, case energy dispersive x-ray (EDX) spectroscopy, linear dependency local emission on composition is disrupted by channeling effects and cross-talk during beam propagation. To...
ABSTRACT In this paper, the fatigue life prediction of a carbon black filled natural rubber was carried out using an artificial neural network. A wide range loading ratios were considered under relaxing and non‐relaxing conditions in order to fully describe response, especially lifetime reinforcement. As reinforcement is generally assumed be due highly thermosensitive phenomenon, namely, strain‐induced crystallisation, tests performed at three different temperatures. The criterion defined...
In this Letter we report on the exploration of axial metal/semiconductor (Al/Ge) nanowire heterostructures with abrupt interfaces. The formation process is enabled by a thermal induced exchange reaction between vapor-liquid-solid grown Ge and Al contact pads due to substantially different diffusion behavior in vice versa. Temperature-dependent I-V measurements revealed metallic properties crystalline segments maximum current carrying capacity about 0.8 MA/cm(2). Transmission electron...
Energy dispersive X-ray spectrometry is used to extract a quantitative 3D composition profile of heterostructured nanowires. The analysis hypermaps recorded along limited number projections, with preliminary calibration the signal associated each element, compared intensity profiles calculated for model structure successive shells circular, elliptic, or faceted cross sections. This discrete tomographic technique applied II-VI nanowires grown by molecular beam epitaxy, incorporating ZnTe and...
Gold-catalyzed ZnTe nanowires were grown at low temperature by molecular beam epitaxy on a ZnTe(111) B buffer layer, under different II/VI flux ratios, including with CdTe insertions. High-resolution electron microscopy and energy-dispersive X-ray spectroscopy (EDX) gave information about the crystal structure, polarity, growth mechanisms. We observe, stoichiometric conditions, simultaneous presence of zinc-blende wurtzite spread homogeneously same sample. Wurtzite are cylinder-shaped...
The outstanding properties of chalcogenide phase-change materials (PCMs) led to their successful use in innovative resistive memory devices where the material is switched between its amorphous and crystalline phases. However, PCMs are easily oxidized at interfaces. Oxidation detrimental device performances. In particular, it reduces data retention time since crystallize a lower temperature than nonoxidized ones. aim this study investigate how oxidation affects crystallization process...
Efficient, mercury-free deep ultraviolet (DUV) light-emitting diodes (LEDs) are becoming a crucial challenge for many applications such as water purification. For decades, the poor p-type doping and difficult current injection of Al-rich AlGaN-based DUV LEDs have limited their efficiency therefore use. We present here significant increase in AlN p-doping thanks to Mg/In codoping, which leads an order magnitude higher Mg solubility limit nanowires (NWs). Optimal electrical activation acceptor...
Different types of buffer layers such as InGaN underlayer (UL) and InGaN/GaN superlattices are now well-known to significantly improve the efficiency c-plane InGaN/GaN-based light-emitting diodes (LEDs). The present work investigates role two different kinds pregrowth (low In-content UL GaN namely "GaN spacer") on emission core–shell m-plane single quantum well (QW) grown around Si-doped c̅-GaN microwires obtained by silane-assisted metal organic vapor phase epitaxy. According photo-...
Research Article| April 01, 1998 Extraterrestrial Ni-rich spinel in upper Eocene sediments from Massignano, Italy Olivier Pierrard; Pierrard 1Centre des Faibles Radioactivités, Laboratoire mixte C.E.A./C.N.R.S., 91198 Gif-sur-Yvette, France Search for other works by this author on: GSW Google Scholar Eric Robin; Robin Robert Rocchia; Rocchia Alessandro Montanari 2Osservatorio Geologico di Coldigioco, 62020 Frontale Apiro, Italy, and Ecole Mines de Paris, Author Article Information Publisher:...