A5035619124- ZnO doping and properties
- Ga2O3 and related materials
- Advanced Semiconductor Detectors and Materials
- Semiconductor Quantum Structures and Devices
- Chalcogenide Semiconductor Thin Films
- Gas Sensing Nanomaterials and Sensors
- Copper-based nanomaterials and applications
- Quantum Dots Synthesis And Properties
- GaN-based semiconductor devices and materials
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Semiconductor materials and devices
- Perovskite Materials and Applications
- Diamond and Carbon-based Materials Research
- Electronic and Structural Properties of Oxides
- 2D Materials and Applications
- Metal and Thin Film Mechanics
- Photonic and Optical Devices
- Semiconductor materials and interfaces
- Nanowire Synthesis and Applications
- Solid-state spectroscopy and crystallography
- High-pressure geophysics and materials
- Ion-surface interactions and analysis
- Crystallography and molecular interactions
- Thin-Film Transistor Technologies
Groupe d’Étude de la Matière Condensée
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Université de Versailles Saint-Quentin-en-Yvelines
2014-2024
Université Paris-Saclay
2016-2024
Canadian Nautical Research Society
2019
Institut Méditerranéen de Biodiversité et d'Ecologie Marine et Continentale
2017
Cheikh Anta Diop University
2009
CEA LETI
2009
Université Grenoble Alpes
2009
Institut polytechnique de Grenoble
2009
The performance of hybrid organic perovskite (HOP) for solar energy conversion is driving a renewed interest in their light emitting properties. recent observation broad visible emission layered HOP highlights potential as white-light emitters. Improvement the efficiency material requires better understanding its photophysical We present in-depth experimental investigations (WL) thin films (C6H11NH3)2PbBr4. broadband, strongly Stokes shifted presents maximum at 90 K when excited 3.815 eV,...
Organic–inorganic hybrid perovskites (OIHP) are developing rapidly as high-performance semiconductors for solid-state solar cells and light emitting devices. Recently, lead-halide two-dimensional (2D) OIHP were found to present bright broadband visible emission, thus, highlighting their potential single component white-light (WL) emitters. This contribution deals with the preparation of a new Cd-based 2D perovskite, chemical formula (C6H11NH3)2CdBr4 (abbreviated compound 1), which structural...
Multifunctional mononuclear iron(<sc>ii</sc>) complex coordinated with six phosphorescent ligands exhibiting correlated spin-crossover transition and enhanced fluorescence.
We report syntheses, crystal and electronic structures, characterization of three new hybrid organic-inorganic halides (R)ZnBr3(DMSO), (R)2CdBr4·DMSO, (R)CdI3(DMSO) (where (R) = C6(CH3)5CH2N(CH3)3, DMSO dimethyl sulfoxide). The compounds can be conveniently prepared as single crystals bulk polycrystalline powders using a DMSO-methanol solvent system. On the basis single-crystal X-ray diffraction results carried out at room temperature 100 K, all have zero-dimensional (0D) structures...
The electrical activity of nitrogen as an acceptor in ZnO has been investigated two ways. First, was introduced by means diallylamine during metalorganic vapor phase epitaxy (MOVPE) yielding incorporation the range 1016–1021 cm−3. This led to significant compensation natural donors with a minimum electron concentration 5×1014 Second, diffusion carried out on undoped MOVPE layers under high pressure conditions stemming from decomposition NH4NO3. Conversion p-type conductivity observed...
We have investigated the temperature dependence of fundamental absorption edge a series Hg1−xCdxTe alloys (with composition x ranging from 0.5 to 1). Analyzing our data in light three-dimensional theory direct-allowed excitons, we find precise values for Γ8-Γ6 interband transition energy range extending 0 300 K. All experimental results, including previous HgTe and mercury-rich alloys, are well accounted using simple empirical formula: Eg (eV)=−0.303(1−x)+1.606x−0.132x(1−x)+[6.3(1−x) −3.25x...
Continued development of GaN-based light emitting diodes is being hampered by constraints imposed current non-native substrates. ZnO a promising alternative substrate but it decomposes under the conditions used in conventional GaN metal organic vapor phase epitaxy (MOVPE). In this work, was grown on ZnO∕c-Al2O3 using low temperature/pressure MOVPE with N2 as carrier and dimethylhydrazine N source. Characterization confirmed epitaxial growth GaN. The lifted-off c-Al2O3 chemically etching away...
We report on experimental evidence of hydrogen-boron interactions in boron-doped diamond from hydrogen diffusion investigations. Original deuterium studies homoepitaxial B-doped films reveal that is limited by the B concentration with a low effective activation energy. These results are consistent ionization and fairly mobile ${H}^{+}$ form pairs ${B}^{\ensuremath{-}}.$ Infrared spectroscopy experiments show boron acceptor electronic transitions removed under hydrogenation.
Films of Cu–In–Se alloys can be electrodeposited in a wide range controlled composition. Annealing treatments under Se pressure transform these precursor films large grain CuInSe2 with improved electronic properties. These modifications are shown to depend on the imposed during treatment allowing certain tailoring properties films. The electrodeposited/selenized presented as obtained from luminescence measurements, Hall effect, and photoelectrochemical characterization. An efficiency 6.5%...
Organic–inorganic hybrid (OIH) materials have emerged as a high-performance class of light emitters, which can be used phosphors for optically pumped white-light-emitting diodes (WLEDs). Here, we report new example broadband white (WL) emission from zero-dimensional lead chloride-based OIH material, namely, (TAE)2[Pb2Cl10](Cl)2 (TAE = tris(2aminoethyl)ammonium (C6N4H22)). Single crystals this compound and its corresponding ammonium salt TAE·HCl been synthesized by slow solvent evaporation...
We report experimental and theoretical results on interband intersubband transitions in GaN quantum wells with strained AlN barriers. All of the samples are grown by molecular-beam epitaxy sapphire (0001) substrates. The show that even at room temperature, strong electron localization occurs plane due to combined effect monolayer thickness fluctuations high internal field layers. also demonstrate absorption is systematically blueshifted n-doped respect nominally undoped as a result many-body...
Unintentionally doped ZnO layers grown epitaxially on a sapphire substrate have been exposed either to hydrogen or deuterium plasma. Secondary ion mass spectroscopy measurements performed subsequently showed rapid diffusion of in these layers. Furthermore, the presence samples is found be responsible for nearly factor 3 increase free electron concentration. This effect attributed passivation compensating acceptor impurities present as-grown
Optical and structural properties of the organic-inorganic hybrid perovskite-type (C6H11NH3)2[PbI4] (abbreviated as C6PbI4) were investigated using optical absorption, photoluminescence (PL), x-ray diffraction measurements. Room temperature, absorption measurements, performed on spin-coated films C6PbI4, revealed two bands at 2.44 3.21 eV. Upon 325 nm (3.815 eV) laser irradiation, strong green PL emission peaks observed 2.41 eV (P1) 2.24 (P2) assigned to free localized excitons,...
The value of the impurity-to-band activation energy EA a dopant is basic feature electrical conductivity semiconductors. Various techniques were used to determine in n-type diamond doped with phosphorus, giving values varying from 0.43 eV 0.63 eV, 0.6 being commonly accepted for ionization phosphorus donors diamond. Nevertheless, up now, dispersion experimental remains unexplained. In this work, we investigate properties set homoepitaxial films different concentrations by Hall effect...
GaN/AlN quantum-dot superlattices grown by molecular-beam epitaxy on silicon (111) or sapphire (0001) substrate have been investigated using high-resolution transmission electron microscopy, photoluminescence, and photo-induced absorption spectroscopy. Under interband excitation at λ≈351 nm, three resonances are observed, respectively peaked 2.1 μm (2.36 μm), 1.46 (1.69 1.28 (1.27 μm) for the sample (sapphire) substrate. We show that absorptions involve conduction-band interlevel transitions...
We report on the efficient room-temperature photoluminescence (PL) quenching of ZnO in presence 2,4-dinitrotoluene (DNT) vapor and for concentration as low 180 ppb. Compared to thin films, nanowires exhibit a strong (95%) fast (41 s) PL intensity DNT vapor. Assuming that is due trapping excitons by adsorbed molecules, Monte-Carlo calculations show nanometric dimensions well better crystallographic quality (longer mean free path) result an enhanced process at origin improved sensing...
For high power electronics, diamond is a promising semiconductor with phosphorus being the current substitutional donor. However, up to now, in (100) oriented grown diamond, only small fraction of atoms incorporated sites (&lt;30%) and epilayer surface exhibits macrosteps. In this work, we present phosphorus-doped where ∼100% are sites. The film low roughness (RMS = 0.5 nm). Our conductive (ρ 5.0 × 106 Ω · cm at 300 K) neutral detected infrared absorption.
Abstract Zinc oxide (ZnO) is a stable, direct bandgap semiconductor emitting in the UV with multitude of technical applications. It well known that ZnO emission can be shifted into green for visible light applications through introduction defects. However, generating consistent and efficient this process challenging, particularly given chemical or atomic origin still under debate. In work we present new method, which coin term desulfurization, creating significantly enhanced quantum...
We examine the influence of strain fields in ZnO epilayers. show that a reversal nature fundamental valence band can be observed similarily to what was reported GaN