A5053620832- Silicon Nanostructures and Photoluminescence
- Semiconductor materials and devices
- Ion-surface interactions and analysis
- Nanowire Synthesis and Applications
- Semiconductor materials and interfaces
- Integrated Circuits and Semiconductor Failure Analysis
- Thin-Film Transistor Technologies
- Silicon and Solar Cell Technologies
- Photonic and Optical Devices
- Laser-Ablation Synthesis of Nanoparticles
- Diamond and Carbon-based Materials Research
- Advanced Memory and Neural Computing
- Gold and Silver Nanoparticles Synthesis and Applications
- Electronic and Structural Properties of Oxides
- Nonlinear Optical Materials Studies
- Ga2O3 and related materials
- Advanced ceramic materials synthesis
- Advanced Electron Microscopy Techniques and Applications
- Photonic Crystals and Applications
- Advanced Surface Polishing Techniques
- Ferroelectric and Negative Capacitance Devices
- Quantum Dots Synthesis And Properties
- Phase-change materials and chalcogenides
- Silicon Effects in Agriculture
- Nanomaterials and Printing Technologies
Centre National pour la Recherche Scientifique et Technique (CNRST)
2025
Centre d’Élaboration de Matériaux et d’Études Structurales
2005-2022
Centre National de la Recherche Scientifique
2009-2022
Université de Toulouse
2011-2019
Institut d'Électronique et des Systèmes
2004-2018
Université Toulouse III - Paul Sabatier
2005-2018
Laboratoire d'Optique Appliquée
2015-2018
Université de Strasbourg
2010-2014
Instituto Nacional de Educação de Surdos
2006
Laboratoire de Physique Corpusculaire de Caen
2004-2005
The correlation between the structural (average size and density) optoelectronic properties [band gap photoluminescence (PL)] of Si nanocrystals embedded in SiO2 is among essential factors understanding their emission mechanism. This has been difficult to establish past due lack reliable methods for measuring distribution from electron microscopy, mainly because insufficient contrast SiO2. With this aim, we have recently developed a successful method imaging matrices. done by using...
The ability of surface passivation to enhance the photoluminescence (PL) emission Si nanocrystals in SiO2 has been investigated. No significant increase average nanocrystal size detected for annealings at 1100 °C between 1 min and 16 h. In contrast, PL intensity steadily increases reaches saturation after 3–4 h annealing time. Such behavior shows an inverse correlation with amount dangling bonds (Pb centers) interface matrix. A postannealing 450 forming gas enhances lifetime, due a reduction...
In silicon nanocrystal based metal–oxide–semiconductor memory structures, tuning of the electron tunneling distance between Si substrate and nanocrystals located in gate oxide is a crucial requirement for pinpointing optimal device architectures. this work it demonstrated that “injection distance” can be achieved by varying Si+ ion energy or thickness during fabrication ultralow-energy implantation. Using an accurate cross-section transmission microscopy (XTEM) method, two-dimensional arrays...
Abstract This study investigates the mechanisms underlying colour production in family Coccinellidae, focusing on two model species: A. bipunctata (L) and C. quatuordecimguttata . In this family, colours have traditionally been attributed primarily to pigments such as carotenoids melanins. We propose an alternative perspective, considering elytra integrated optical medium whose properties result from both its architectural design of constituent materials, including matrix pigments. present...
Pump and probe experiments on Er3+ ions coupled to Si nanoclusters have been performed in rib-loaded waveguides investigate optical amplification at 1.5μm. Rib-loaded were obtained by photolithographic reactive ion etching of Er-doped silica layers containing grown sputtering. Insertion losses measurements the infrared erbium absorption region allowed gauge an cross section about 5×10−21cm2 1534nm. Signal transmission under pumping 1310nm shows confined carrier nanoclusters. Amplification...
The microstructural and optical analysis of SiO2 layers emitting white luminescence is reported. These structures have been synthesized by sequential Si+ C+ ion implantation high-temperature annealing. Their emission results from the presence up to three bands in photoluminescence (PL) spectra, covering whole visible spectral range. characterization reveals a complex multilayer structure: Si nanocrystals are only observed outside main C-implanted peak region, with lower density closer...
We compare the morphology and optical response of plasmonic nanostructures produced by pulsed laser deposition, consisting a 2D distribution Ag nanoparticles exposed to air or buried under an amorphous Al2O3 layer whose thickness is tuned in 0.5 14 nm range. observe that covering process leads drastic changes content, which are interpreted terms sputtering atoms promoted incoming Al ions. This avoided as soon embedded subnanometer-thick Al2O3. Meanwhile, spectral position nanoparticles'...
The characteristics of nonvolatile memories making use Si nanocrystals as charge storage elements buried in the gate oxide regular metal–oxide–semiconductor transistors strongly depend on distances between and two electrodes, channel gate. In this letter, we compare transmission electron microscopy methods that can be used to extract such distances. We demonstrate by using image simulations conventional under out-of-Bragg underfocused conditions is fastest most efficient technique for...
In this work, silicon-rich silicon nitride (SRN) layers were deposited on a wafer by microwave-assisted plasma-enhanced chemical vapor deposition (MW-PECVD) using NH3 and SiH4 as precursor gases. The Si excess in the as-deposited determined Rutherford backscattering technique was controlled varying gas ratio. We able to produce nanoparticles (Si-nps) (SiNx) upon thermal annealing at high temperature. Energy-filtered TEM (EFTEM), complemented photoluminescence measurements, used identify...
Abstract In this study, a wide range of a-SiN x :H films with an excess silicon (20 to 50%) were prepared electron-cyclotron resonance plasma-enhanced chemical vapor deposition system under the flows NH 3 and SiH 4 . The silicon-rich (SRSN) sandwiched between bottom thermal SiO 2 top Si N layer, subsequently annealed within temperature 500-1100°C in study effect annealing on light-emitting charge storage properties. A strong visible photoluminescence (PL) at room has been observed for...
In this paper we use spectroscopic ellipsometry to investigate the optical properties of silicon quantum dots (Si-QDs) embedded in silicon-rich nitride (SRSN) films over (1.5–5.9 eV) photon energy range. These were elaborated by microwave plasma enhanced chemical vapor deposition for various gas flow ratio [R=(NH3)/(SiH4)]. We have analyzed ellipsometric data using modeling methods: Forouhi–Bloomer (FB) and Tauc–Lorentz (TL) dispersion formulas wavelength-by-wavelength (λ-by-λ) numerical...
Silicon nanocrystals embedded in a thin oxide layer can be used as charge storage elements nonvolatile memory devices. The structural characteristics of the and their position determine electrical properties In this work, silicon have been formed by ultralow-energy implantation (0.65–2.0 keV) 10 nm thermally grown SiO2 film on Si (100) followed thermal treatment. A time flight secondary ion mass spectrometry (TOF-SIMS) methodology has developed to detect presence characterize them. allows...
Semiconductor nanowires have an excellent ability to trap, guide, scatter, or absorb light for specific morphology-dependent resonant optical modes. The electromagnetic field enhancement associated with these modes could be used modify the luminescence of emitters positioned in vicinity nanowire, a way similar plasmonic nanostructures. We show that photoluminescence single plane silicon nanocrystals silica, at about 3 nm below surface, can enhanced by factor 2 presence nanowire antenna on...
In this letter, we propose an original method to investigate Si nanocrystal-based nonvolatile memory devices, taking benefit of the photoluminescence (PL) spectroscopy and specific optoelectronic properties nanocrystals (Si-NCs). Ordered two-dimensional-arrays Si-NCs were synthesized by ultralow-energy ion implantation in 7-nm-thick SiO2 subsequent annealing. The population characteristics (size density) adjusted different oxidizing This allowed, at same time, progressive healing oxide...
This work reports on the structural and optical properties of multilayers composed silicon dioxide (SiO2) rich nitride (SRN) films. These nanometer scale layers have been alternately deposited by electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR-PECVD) quartz (Si) substrates. The samples then annealed at high temperature in order to obtain a crystallization Si atoms present excess SRN formation crystalline has witnessed resolution transmission microscopy (HREM)...