Environnement francophone en milieu plurilingue / / Musanji Nglasso-Mwatha

• Record Nr.: UNINA9910495685203321
• Autore: Abdallah Kaouthar Ben
• Pubbl/distr/stampa: Pessac, : Presses Universitaires de Bordeaux, 2020
• ISBN: 979-1-03-000671-1
• Descrizione fisica: 1 online resource (602 p.)
• Collana: Études africaines et créoles
• Altri autori (Persone): AbdelkaderYamna; Ambassa-BetokoMarie-Thérèse; AmedegnatoOzouf Sénamin; AnatéKouméalo; ArezkiAbdenour; BelhaibaAïcha; BenramdaneFarid; BilliezJacqueline; BoumediniBelkacem; Brou-DialloClémentine; Chauvin-VilenoAndrée; CheikhMohamed Vall Ould; DaflMoussa; EbongueAugustin Emmanuel; EloundouVenant Eloundou; EyeangEugénie; FertatOmar; HadriaNebia Dadoua; KabaleSim Kilosho; KébéAbou Bakry; KomeFerdinand Njoh; KpatchaKomi; MadiniMongi; MalekAzzedine; MassoumouOmer; Mbonji-MouelléMarie-Madeleine; MusindeJulien Kilanga; NapalaKuwèdaten; NdawouoMartine Fandio; Ngalasso-MwathaMusanji; NoumssiGérard Marie; NoyauColette; OuedraogoDragoss; PaliTchaa; SfaxiHafedh; TréfaultThierry; TumbweRomain Kasoro; WambaRodolphine-Sylvie; ZamboClaude Éric Owono; ZeBarnabé Mbala; Nglasso-MwathaMusanji
• Soggetti: Linguistics; toponymie; sociolinguistique; diglossie; plurilinguisme; environnement linguistique; écologie des langues; écolinguistique; langues en contact; écarts et norme; francophonie d’Afrique
• Lingua di pubblicazione: Francese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Sommario/riassunto: La notion d’environnement linguistique ressortit aux développements les plus récents de ce qu’on appelle l’écologie des langues ou, plus précisément, l’écolinguistique. La langue est, comme tout organisme social, conditionnée par l’influence du milieu dans lequel elle vit et qu’elle influence à son tour. L’objectif de ce livre, dont le propos concerne essentiellement le continent africain, est de décrire, caractériser et illustrer la réalité de l’environnement francophone dans les espaces où le français coexiste avec d’autres langues, souvent en position dominante juridiquement mais minoritaire socialement. Il s’agit, concrètement, d’apprécier l’importance et la qualité de l’offre en français dans des contextes où celui-ci n’est pas la langue maternelle des populations. La présence du français est observée dans le marquage du territoire (toponymie, odonymie ou hydronymie) et de l’espace social (anthroponymie, ethnonymie ou glossonymie). Elle est examinée dans l’affichage administratif et commercial. Les lieux, les moments et les situations de contact réel avec le français sont identifiés tout comme les formes de langage pratiquées au quotidien, les normes valorisées et les écarts stigmatisés. L’impact de la francophonie sur la vie quotidienne des populations est évalué autant que son efficacité dans les secteurs formels (école, administration, entreprise) et non-formels (alphabétisation ou petit commerce). Peut-on identifier les lignes de partage, les circuits d’échange et les ; possibilités de dialogue avec les langues locales dans une perspective de développement ? Quelle est l’efficacité du français dans la circulation des informations destinées aux masses populaires ? Quelle est sa capacité de mobilisation ? Quelle est la part de rêve qu’il offre aux jeunes pour l’avenir ? Les auteurs de ce livre se sont efforcés de répondre à toutes ces interrogations avec clarté, rigueur et objectivité.

Gallium oxide : technology, devices and applications / / edited by Stephen Pearton, Fan Ren, Michael Mastro

• Record Nr.: UNINA9910583355203321
• Pubbl/distr/stampa: Amsterdam, Netherlands : , : Elsevier, , [2018]; ©2018
• ISBN: 0-12-814522-6
• Descrizione fisica: 1 online resource (481 pages)
• Collana: Metal oxides series
• Disciplina: 621.38152
• Soggetti: Gallium compounds; Oxides
• Lingua di pubblicazione: Inglese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Nota di contenuto: Front Cover -- Gallium Oxide: Technology, Devices and Applications -- Copyright -- Contents -- List of contributors -- Series editor's biography -- Editors biography -- Preface to the series -- Preface -- Part One: Growth technology of Ga2O3 -- Chapter 1: Progress in MOVPE growth of Ga2O3 -- 1.1. Introduction -- 1.2. Homoepitaxial deposition of β-Ga2O3 -- 1.3. Heteroepitaxial deposition of β-Ga2O3 -- 1.4. Heteroepitaxial deposition of -Ga2O3 -- References -- Chapter 2: MBE growth and characterization of gallium oxide -- 2.1. Introduction -- 2.2. MBE growth of Ga2O3 and materials characterization -- 2.2.1. Oxide MBE equipment considerations -- 2.2.2. Amorphous Ga2O3 for gate dielectrics -- 2.2.3. Heteroepitaxy of Ga2O3 -- 2.2.4. Homoepitaxy of Ga2O3 -- 2.2.4.1. Substrate selection -- 2.2.4.2. Substrate cleaning -- 2.2.4.3. MBE growth optimization -- Substrate temperature -- Ga and oxygen flux -- 2.2.5. Stabilizing ; metastable phases -- 2.2.5.1. Tin-assisted -Ga2O3 -- 2.2.5.2. Indium-assisted -Ga2O3 -- 2.3. Current status and future prospects -- 2.4. Summary -- Acknowledgments -- References -- Chapter 3: Properties of sputter-deposited gallium oxide -- 3.1. Introduction -- 3.2. Experimental -- 3.2.1. Film fabrication -- 3.2.2. Characterization -- 3.2.2.1. Rutherford backscattering spectroscopy (RBS) -- 3.2.2.2. X-ray photoelectron spectroscopy (XPS) -- 3.2.2.3. Grazing incidence X-ray diffraction (GIXRD) -- 3.2.2.4. UV-vis spectroscopy -- 3.2.2.5. Spectroscopic ellipsoemetry -- 3.2.2.6. Mechanical characterization -- 3.3. Results and discussion -- 3.3.1. Chemical composition -- 3.3.1.1. RBS -- 3.3.1.2. XPS -- 3.3.2. Crystal structure -- 3.3.3. Optical properties -- 3.3.3.1. Spectrophotometry -- 3.3.4. Mechanical properties -- 3.4. Summary and conclusions -- Acknowledgments -- References.; Chapter 4: Synthesis, optical characterization, and environmental applications of β-Ga2O3 nanowires -- 4.1. Introduction -- 4.2. Ambient controlled synthesis of β-Ga2O3 nanowires -- 4.3. Optical characterization of β-Ga2O3 nanowires -- 4.4. Photocatalytic property of β-Ga2O3 nanowires -- 4.5. Summary -- References -- Chapter 5: Growth, properties, and applications of β-Ga2O3 nanostructures -- 5.1. Introduction -- 5.2. Study of β-Ga2O3 nanostructures -- 5.2.1. β-Ga2O3 nanostructures using the CVD technique -- 5.2.2. β-Ga2O3 nanowires: Morphological and structural properties -- 5.2.3. Optical properties of β-Ga2O3 nanostructures -- 5.2.4. Application of β-Ga2O3 nanostructures -- 5.3. Functional nanowires based on β-Ga2O3 -- 5.3.1. Coaxial β-Ga2O3/GaN nanowires through ammonification of β-Ga2O3 nanowires -- 5.3.2. ZnGa2O4 nanowires through coaxial ZnO/β-Ga2O3 nanowires -- 5.3.3. β-Ga2O3 nanowires template mediated high-quality ultralong GaN nanowires -- 5.4. Conclusions and future perspective -- Acknowledgments -- References -- Part Two: Properties and Processing -- Chapter 6: Properties of (In,Ga)2O3 alloys -- 6.1. Introduction -- 6.2. Overview on crystal structures observed in (In,Ga)2O3 -- 6.3. Lattice parameters of bulk material -- 6.3.1. Rhombohedral (InxGa1-x)2O3 -- 6.3.2. Monoclinic β-(InxGa1-x)2O3 -- 6.3.3. Cubic (GaxIn1-x)2O3 -- 6.3.4. Hexagonal InGaO3 -- 6.4. Thin film growth -- 6.4.1. Growth of (In,Ga)2O3 thin films with lateral composition spread by PLD -- 6.4.2. Growth and phase formation of (In,Ga)2O3 thin films -- 6.5. Deep-UV absorption and band gap engineering -- 6.6. Phonon modes -- 6.7. Dielectric function and index of refraction -- 6.8. Schottky barrier diodes -- 6.9. Photodetectors -- 6.10. Summary and outlook -- References -- Further reading -- Chapter 7: Low-field and high-field transport in β-Ga2O3 -- 7.1. Introduction.; 7.2. Electron-phonon interaction in β-Ga2O3 -- 7.2.1. Electron-LO phonon coupling -- 7.2.2. Electron-LO phonon-plasmon coupling -- 7.2.3. Short-range (nonpolar) electron-phonon coupling -- 7.3. Electron mobility in β-Ga2O3 -- 7.3.1. Bulk electron mobility -- 7.3.2. 2DEG mobility -- 7.4. Velocity-field curves in β-Ga2O3 -- 7.5. Summary -- Acknowledgments -- References -- Chapter 8: Electron paramagnetic resonance (EPR) from β-Ga2O3 crystals -- 8.1. Introduction -- 8.2. Crystal structure of β-Ga2O3 -- 8.3. Shallow donors and conduction electrons -- 8.4. Acceptors and self-trapped holes -- 8.4.1. Doubly ionized gallium vacancies -- 8.4.2. Neutral Mg acceptors -- 8.4.3. Self-trapped holes -- 8.5. Transition-metal and rare-earth ions -- 8.5.1. Cr3+ ions -- 8.5.2. Fe3+ ions -- 8.5.3. Mn2+ ions -- 8.5.4. Ti3+ ions -- 8.5.5. Er3+ ions -- 8.6. Oxygen vacancies -- Acknowledgments -- References -- Chapter 9: Hydrogen in Ga2O3 -- 9.1. Introduction -- 9.2. Hydrogen in the transparent conducting ; oxides ZnO, SnO2, and In2O3 -- 9.3. Hydrogen in β-Ga2O3 -- 9.3.1. Theory -- 9.3.2. Thermal stability of deuterium in Ga2O3 -- 9.3.3. Muon spin resonance -- 9.3.4. Vibrational properties of H in Ga2O3 -- 9.3.4.1. Vibrational spectroscopy -- 9.3.4.2. Evidence for a ``hidden hydrogen´´ species -- 9.3.4.3. Theory of defect structures and their vibrational properties -- 9.3.4.4. Additional IR lines -- 9.4. Conclusion -- Acknowlegments -- References -- Chapter 10: Ohmic contacts to gallium oxide -- 10.1 Introduction -- 10.2 Ohmic contacts and contact resistance -- 10.3 Ohmic contacts to gallium oxide -- 10.4 Development of Ohmic contacts for Ga2O3 microelectronics -- 10.5 Research opportunities for Ohmic contacts to Ga2O3 -- Acknowledgment -- References -- Chapter 11: Schottky contacts to β-Ga2O3 -- Chapter Outline -- 11.1. Introduction.; 11.2. Physics of Schottky contacts and SBH measurements -- 11.2.1. Physics of Schottky contacts -- 11.2.2. Shottky Barrier Height measurements -- 11.2.2.1. phiB calculation from I-V measurements -- 11.2.2.2. phiB calculation from I-V-T measurements (Richardson plot) -- 11.2.2.3. phiB calculation from C-V measurements -- 11.2.2.4. phiB calculation from IPE measurements -- 11.3. Properties of Ga2O3 for SBDs -- 11.4. Schottky contacts on β-Ga2O3: Materials and processing -- 11.5. Defects relevant to β-Ga2O3 Schottky contacts -- 11.5.1. Point defects and impurities -- 11.5.2. Extended crystallographic defects -- 11.5.3. Defect states in the band gap -- 11.6. Nonideal and inhomogeneous Schottky barriers -- 11.7. β-Ga2O3 Schottky devices -- 11.7.1. SBDs as rectifiers -- 11.7.2. Metal-semiconductor field-effect transistors -- 11.8. Summary -- Acknowledgments -- References -- Chapter 12: Dry etching of Ga2O3 -- 12.1. Introduction -- 12.2. Dry etching -- 12.2.1. Mechanisms of dry etching -- 12.3. Dry etching techniques -- 12.4. Etch results for Ga2O3 -- 12.4.1. Etch rates -- 12.4.2. Damage induced by dry etching -- 12.5. Summary -- Acknowledgments -- References -- Chapter 13: Band alignments of dielectrics on (-201) β-Ga2O3 -- 13.1. Introduction -- 13.2. Methods -- 13.2.1. Determination of bandgap -- 13.2.2. Determination of band offset -- 13.3. Band offsets -- 13.3.1. Aluminum oxide -- 13.3.2. Lanthanum aluminate -- 13.3.3. SiO2 and HfSiO4 -- 13.3.4. Indium tin oxide -- 13.3.5. Aluminum zinc oxide (AZO) -- 13.4. Conclusion -- References -- Chapter 14: Radiation damage in Ga2O3 -- 14.1. Introduction -- 14.2. Radiation damage in wide bandgap semiconductors -- 14.3. Properties of Ga2O3 -- 14.4. Radiation damage effects in Ga2O3 -- 14.5. Summary and conclusion -- Acknowledgments -- References -- Part Three: Applications -- Chapter 15: Ga2O3 nanobelt devices.; 15.1. Introduction -- 15.1.1. Bottom-up methods -- 15.1.2. Top-down methods -- 15.2. β-Ga2O3-based optoelectronic nanodevice -- 15.2.1. Introduction of β-Ga2O3-based optoelectronic nanodevice -- 15.2.2. Development of β-Ga2O3-based photodetectors -- 15.2.2.1. Photoconductive detectors -- 15.2.2.2. Metal-semiconductor-metal (MSM) structure -- 15.2.2.3. Photovoltaic structure -- 15.3. β-Ga2O3-based nanoelectronic devices -- 15.3.1. Introduction of β-Ga2O3 nanobelt-based transistors -- 15.3.2. Development of β-Ga2O3 nanobelt-based transistors -- 15.3.2.1. Back-gated FETs -- 15.3.2.2. Top-gated FETs -- 15.3.2.3. Heterostructure MISFETs -- 15.4. Summary -- References -- Chapter 16: Advances in Ga2O3 solar-blind UV photodetectors -- 16.1. Introduction -- 16.1.1. The UV spectrum -- 16.1.2. Applications: UV spectrum -- 16.1.3. Ga2O3-Background -- 16.2. Figures of merit for photodetectors -- 16.2.1. Quantum efficiency and spectral responsivity -- 16.2.2. Bandwidth, rise/fall times, and persistent photoconductivity -- 16.2.3. Noise equivalent power and ; specific detectivity -- 16.2.4. UV-to-visible rejection ratio -- 16.2.5. Linearity -- 16.3. β-Ga2O3 UV photodetectors: Types, operational principles, and status -- 16.3.1. Metal-semiconductor-metal photodetectors -- 16.3.2. Schottky photodetectors -- 16.4. Gain mechanism and barrier height calculation -- 16.5. Comparison with AlGaN deep-UV photodetectors -- 16.6. Design consideration, possible geometries, and arrays of detectors for deep UV detection -- 16.7. Summary, conclusion/future work -- References -- Chapter 17: Power MOSFETs and diodes -- 17.1. Introduction -- 17.2. Properties -- 17.3. Schottky diodes -- 17.4. Power MOSFETs -- 17.5. Application space and competing technologies -- 17.6. Future -- References -- Chapter 18: Ga2O3-photoassisted decomposition of insecticides -- 18.1. Introduction.; 18.2. Photochemical and photocatalytic degradation reactions.
• Sommario/riassunto: Gallium Oxide: Technology, Devices and Applications discusses the wide bandgap semiconductor and its promising applications in power electronics, solar blind UV detectors, and in extreme environment electronics. It also covers the fundamental science of gallium oxide, providing an in-depth look at the most relevant properties of this materials system. High quality bulk Ga2O3 is now commercially available from several sources and n-type epi structures are also coming onto the market. As researchers are focused on creating new complex structures, the book addresses the latest processing and synthesis methods. Chapters are designed to give readers a complete picture of the Ga2O3 field and the area of devices based on Ga2O3, from their theoretical simulation, to fabrication and application.