Download or read book EPITAXIE LOCALISEE PAR JETS CHIMIQUES SUR SUBSTRATS GAAS ET INP written by PHILIPPE.. LEGAY and published by . This book was released on 1995 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: CETTE THESE RAPPORTE UN TRAVAIL SUR L'OPTIMISATION DE LA LOCALISATION DE L'EPITAXIE DANS LE PLAN DU SUBSTRAT PAR LA TECHNIQUE D'EPITAXIE PAR JETS CHIMIQUES (EJC). CETTE ETUDE EST MENEE POUR LES SYSTEMES DE SEMI-CONDUCTEURS III-V ASSOCIES AUX SUBSTRATS GAAS ET INP. L'EPITAXIE PAR JETS CHIMIQUES EST UNE TECHNIQUE DE CROISSANCE EFFECTUEE SOUS VIDE A PARTIR DE PRECURSEURS GAZEUX D'ORGANOMETALLIQUES POUR LES ELEMENTS III ET D'HYDRURES POUR LES ELEMENTS V. L'ETUDE DES MECANISMES DE CROISSANCE SPECIFIQUES A CETTE TECHNIQUE A PERMIS DE DEFINIR LES CONDITIONS OPTIMALES DE TEMPERATURE DE CROISSANCE POUR LES DIFFERENTS SEMI-CONDUCTEURS GAAS, GAINP, INP, GAINAS ET GAINASP. LA TECHNIQUE D'EPITAXIE LOCALISEE ETUDIEE EST CELLE BASEE SUR LA SELECTIVITE DE CROISSANCE SELON LA NATURE DE LA SURFACE DU SUBSTRAT. AINSI LE MASQUAGE PARTIEL DU SUBSTRAT PAR UN FILM DE DIELECTRIQUE A PERMIS POUR CERTAINES CONDITIONS OPERATOIRES DE LOCALISER LA CROISSANCE UNIQUEMENT DANS LES FENETRES DU SUBSTRAT SEMI-CONDUCTEUR. LA TEMPERATURE DE CROISSANCE APPARAIT ETRE LE PARAMETRE PRIMORDIAL QUI EMPECHE AU DELA D'UN CERTAIN SEUIL TOUTE NUCLEATION SUR LE MASQUE. POUR LES DIFFERENTS MATERIAUX ETUDIES, ET EN OPTIMISANT LES AUTRES PARAMETRES DE DEPENDANCE (VITESSE DE CROISSANCE, NATURE DU MASQUE, DU SEMI-CONDUCTEUR ET DES PRECURSEURS D'EPITAXIE), CETTE TEMPERATURE CRITIQUE A PU ETRE ABAISSEE DANS LES FENETRES DE TEMPERATURES DE CROISSANCE OPTIMALES, PREALABLEMENT DEFINIES. LA CARACTERISATION DE CES EPITAXIES LOCALISEES MONTRE QU'ELLES SONT UNIFORMES EN EPAISSEUR, EN COMPOSITION (POUR LES ALLIAGES) QUELLE QUE SOIT LA SUPERFICIE ET LA GEOMETRIE DU MASQUE DEPOSE. L'OPTIMISATION DES PROFILS DE CROISSANCE LOCALISES POUR GAAS ET INP MET EN EVIDENCE DES DIFFERENCES DE COMPORTEMENT ENTRE CES DEUX MATERIAUX QUI SONT DISCUTES. ENFIN, CE TRAVAIL EST APPLIQUE A DEUX DEMONSTRATIONS POUR COMPOSANTS. LE PREMIER, EN MICROELECTRONIQUE SUR GAAS, CONSISTE A AMELIORER LA TECHNOLOGIE, LES PERFORMANCES ET LA FIABILITE D'UN TRANSISTOR BIPOLAIRE A HETEROJONCTION. PAR REPRISE D'EPITAXIE LOCALISEE DE LA BASE ET DU COLLECTEUR, LES TROIS CONTACTS DU COMPOSANT SONT AMENES A UN MEME NIVEAU ET SONT AMELIORES PAR LA CROISSANCE DE MATERIAUX TRES DOPES ET A FAIBLE BARRIERE SCHOTTKY DE SURFACE. LA SECONDE APPLICATION CONCERNE L'INTEGRATION MONOLITHIQUE D'UN GUIDE OPTIQUE AVEC UN COMPOSANT PHOTONIQUE. DANS CE CAS LA STRUCTURE ENTIERE DU GUIDE OPTIQUE EST EPITAXIEE LOCALEMENT DANS UN CAISSON GRAVE DANS LA STRUCTURE DU COMPOSANT INITIAL ET LE PROFIL DE CROISSANCE OBTENU EST FAVORABLE POUR UN BON COUPLAGE BOUT A BOUT AVEC LE COMPOSANT PHOTONIQUE. IL A ETE MESURE A 85%

Download or read book EPITAXIE PAR JETS CHIMIQUES D HETEROSTRUCTURES INP GA 0 4 7IN 0 5 3AS written by LALLA FATIHA.. ALOUI and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: L'EPITAXIE PAR JETS CHIMIQUES (EJC), NOUVELLE METHODE DE CROISSANCE, COMBINE LA MAJORITE DES AVANTAGES DES DEUX TECHNIQUES MERES. L'EPITAXIE PAR ORGANOMETALLIQUES (EOM) ET L'EPITAXIE PAR JETS MOLECULAIRES (EJM). LE TRAVAIL PRESENTE DANS CE MANUSCRIT DECRIT ET DEMONTRE EXPERIMENTALEMENT CERTAINS AVANTAGES OFFERTS PAR CETTE TECHNIQUE D'EPITAXIE. DE PLUS, CETTE ETUDE CONSTITUE UNE PREMIERE VALIDATION DE CETTE METHODE DE CROISSANCE PAR L'OBTENTION, DANS LE SYSTEME DE SEMICONDUCTEURS INP/GAINAS, DE COUCHES PURES, DE STRUCTURES A PUITS QUANTIQUES ET DE COMPOSANTS D'EMISSION LASER. L'EQUIPEMENT EXPERIMENTAL MIS AU POINT ET SON OPTIMISATION, NOTAMMENT DE LA PARTIE D'INTRODUCTION DES SOURCES GAZEUSES, SONT D'ABORD PRESENTES. L'ETUDE PORTE ESSENTIELLEMENT SUR L'OPTIMISATION DES CONDITIONS DE CROISSANCE DES COMPOSES GAAS, GAINAS ET INP, POUR SURTOUT MINIMISER L'INCORPORATION DU CARBONE QUI APPARAIT ETRE L'IMPURETE RESIDUELLE MAJORITAIRE. DES COUCHES INP AVEC UN DOPAGE INTRINSEQUE AUSSI FAIBLE QUE 2 10#1#4 CM##3 ET UNE MOBILITE DE 112000 A 77 K ONT AUSSI ETE OBTENUES. UN MODELE POUR EXPLIQUER L'INCORPORATION OBSERVE AU CARBONE ET SON ACTIVITE ELECTRIQUE DANS CES DIFFERENTS SEMICONDUCTEURS EN FONCTION DE LA TEMPERATURE DE CROISSANCE ET DU RAPPORT V/III EST AUSSI DISCUTE. L'INCORPORATION VOLONTAIRE D'IMPURETES DOPANTES DE TYPE N (SI) ET P (BE) EVAPORES A PARTIR DE SOURCES SOLIDES EST AUSSI ETUDIE. LES POTENTIALITES DE LA TECHNIQUE SONT ENFIN DEMONTREES PAR L'EPITAXIE SANS INTERRUPTION DE CROISSANCE AUX HETERO-INTERFACES DE STRUCTURES INP/GAINAS AUSSI MINCES QUE 12 A ET CELLE DES DOUBLES HETEROSTRUCTURES LASER AVEC UN COURANT DE SEUIL DE 1,3 KA/CM#2

Download or read book Eighth International Conference on Indium Phosphide and Related Materials written by and published by . This book was released on 1996 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Epitaxie par jets mol culaires sources gazeuses des mat riaux AlGaInP sur substrat GaAs pour applications hyperfr quences written by Olivier Schuler and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les applications actuelles de la micro-electronique requierent des composants de plus en plus rapides. Dans cette perspective, nous avons mis en evidence les potentialites des materiaux phosphores (alga)inp sur gaas elabores par epitaxie par jets moleculaires a sources gazeuses. Nous avons, tout d'abord, effectue des calculs afin d'extraire les principales caracteristiques physiques des alliages relaxes et contraints. Nous avons optimise les conditions de croissance des alliages (al#xga#1##x)#0#,#5#0in#0#,#5#0p en accord de maille et determine experimentalement la transition gap direct - gap indirect. Le dopage volumique et par plans a revele la presence de pieges pour des alliages riches en aluminium. La relaxation des alliages gainp contraints en tension et en compression a ete observee par diffraction d'electrons ; nous montrons que les alliages contraints en tension peuvent etre le siege d'une decomposition spinodale. Si la croissance des materiaux massifs n'a pas pose de problemes, il n'en a pas ete de meme lors de la realisation des premieres heterostructures. Des mesures de photoluminescence ont revele des interfaces arseniures-phosphures diffuses. Le profil de composition en elements v aux interfaces a ete determine par xps et nous avons montre que le caractere diffus des interfaces est cause par des effets extrinseques lies au dispositif experimental. Nous avons propose une methode originale d'habillage de l'interface par alinp, pour obtenir de bonnes caracteristiques de transfert des electrons dans les simples et doubles heterojonctions.

Download or read book Molecular Beam Epitaxy written by John Wilfred Orton and published by . This book was released on 2015 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is a history of Molecular Beam Epitaxy (MBE) as applied to the growth of semiconductor thin films (note that it does not cover the subject of metal thin films). It begins by examining the origins of MBE, first of all looking at the nature of molecular beams and considering their application to fundamental physics, to the development of nuclear magnetic resonance and to the invention of the microwave MASER. It shows how molecular beams of silane (SiH4) were used to study the nucleation of silicon films on a silicon substrate and how such studies were extended to compound semiconductors such as GaAs. From such surface studies in ultra-high vacuum the technique developed into a method of growing high quality single crystal films of a wide range of semiconductors. Comparing this with earlier evaporation methods of deposition and with other epitaxial deposition methods such as liquid phase and vapour phase epitaxy (LPE and VPE). The text describes the development of MBE machines from the early 'home-made' variety to that of commercial equipment and show how MBE was gradually refined to produce high quality films with atomic dimensions. This was much aided by the use of various in-situ surface analysis techniques, such as reflection high energy electron diffraction (RHEED) and mass spectrometry, a feature unique to MBE. It looks at various modified versions of the basic MBE process, then proceed to describe their application to the growth of so-called 'low-dimensional structures' (LDS) based on ultra-thin heterostructure films with thickness of order a few molecular monolayers. Further chapters cover the growth of a wide range of different compounds and describe their application to fundamental physics and to the fabrication of electronic and opto-electronic devices. The authors study the historical development of all these aspects and emphasise both the (often unexpected) manner of their discovery and development and the unique features which MBE brings to the growth of extremely complex structures with monolayer accuracy.

Download or read book ZnO Thin Films written by Paolo Mele and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zinc oxide (ZnO) is an n-type semiconductor with versatile applications such as optical devices in ultraviolet region, piezoelectric transducers, transparent electrode for solar cells and gas sensors. This book "ZnO Thin Films: Properties, Performance and Applications" gives a deep insight in the intriguing science of zinc oxide thin films. It is devoted to cover the most recent advances and reviews the state of the art of ZnO thin films applications involving energy harvesting, microelectronics, magnetic devices, photocatalysis, photovoltaics, optics, thermoelectricity, piezoelectricity, electrochemistry, temperature sensing. It serves as a fundamental information source on the techniques and methodologies involved in zinc oxide thin films growth, characterization, post-deposition plasma treatments and device processing. This book will be invaluable to the experts to consolidate their knowledge and provide insight and inspiration to beginners wishing to learn about zinc oxide thin films.

Download or read book Organic Solid State Lasers written by Sébastien Forget and published by Springer. This book was released on 2013-07-03 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic lasers are broadly tunable coherent sources, potentially compact, convenient and manufactured at low-costs. Appeared in the mid 60’s as solid-state alternatives for liquid dye lasers, they recently gained a new dimension after the demonstration of organic semiconductor lasers in the 90's. More recently, new perspectives appeared at the nanoscale, with organic polariton and surface plasmon lasers. After a brief reminder to laser physics, a first chapter exposes what makes organic solid-state organic lasers specific. The laser architectures used in organic lasers are then reviewed, with a state-of-the-art review of the performances of devices with regard to output power, threshold, lifetime, beam quality etc. A survey of the recent trends in the field is given, highlighting the latest developments with a special focus on the challenges remaining for achieving direct electrical pumping of organic semiconductor lasers. A last chapter covers the applications of organic solid-state lasers.

Download or read book Physical Properties of Amorphous Materials written by David Adler and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Institute for Amorphous Studies was founded in 1982 as the international center for the investigation of amorphous mate rials. It has since played an important role in promoting the und er standing of disordered matter in general. An Institute lecture series on "Fundamentals of Amorphous Materials and Devices" was held during 1982-83 with distinguished speakers from universities and industry. These events were free and open to the public ,and were attended by many representatives of the scientific community. The lectures themselves were highly successful inasmuch as they provided not only formal instruction but also an opportunity for vigorous and stimulating debate. That last element could not be captured within the pages of a book I but the lectures concentrated on the latest advances in the field I which is why their essential contents are he re reproduced in collective form. Together they constitute an interdisciplinary status report of the field. The speakers brought many different viewpoints and a variety of back ground experiences io bear on the problems involved I but though language and conventions vary I the essential unity of the concerns is very clear I as indeed are the ultimate benefits of the many-sided approach.

Download or read book Laser 50 Years Of Discoveries written by Fabien Bretenaker and published by World Scientific. This book was released on 2014-10-27 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique book provides an overview of the principle and applications of lasers enriched with numerous illustrations.Being over fifty years old, lasers continue to amaze us. Their performance characteristics are constantly reaching new limits, and the scope of their applications continues to expand. Yet, it took years of effort by teams of physicists to transform the fundamental notions of Einstein into the first experimental beam of laser light. And history is still going on as fundamental research is now triggered by its remarkable properties.This book addresses every aspects of laser light, from its fundamental principles to its industrial applications, at a level particularly suited for high school teachers, students, and anybody curious about science and technology.