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Ingénierie Des Défauts Cristallins Pour L'obtention De Gan Semi-Polaire

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Ingénierie Des Défauts Cristallins Pour L'obtention De Gan Semi-Polaire Ingénierie des défauts cristallins pour l’obtention de GaN semi-polaire hétéroépitaxié de haute qualité en vue d’applications optoélectroniques Florian Tendille To cite this version: Florian Tendille. Ingénierie des défauts cristallins pour l’obtention de GaN semi-polaire hétéroépitaxié de haute qualité en vue d’applications optoélectroniques. Autre [cond-mat.other]. Université Nice Sophia Antipolis, 2015. Français. NNT : 2015NICE4094. tel-02947430 HAL Id: tel-02947430 https://tel.archives-ouvertes.fr/tel-02947430 Submitted on 24 Sep 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITE NICE-SOPHIA ANTIPOLIS - UFR Sciences Ecole Doctorale de Sciences Fondamentales et Appliquées THESE pour obtenir le titre de Docteur en Sciences de l’UNIVERSITE de Nice -Sophia Antipolis Discipline : Physique présentée et soutenue par Florian TENDILLE Ingénierie des défauts cristallins pour l’obtention de GaN semi-polaire hétéroépitaxié de haute qualité en vue d’applications optoélectroniques Thèse dirigée par Philippe VENNÉGUÈS et co-dirigée par Philippe DE MIERRY Soutenue publiquement le : 24-11-2015 Jury : N. Grandjean Professeur, EPFL - LASPE, Lausanne Rapporteur T. Baron Directeur de recherche, CNRS/CEA - LTM, Grenoble Rapporteur E. Monroy Ingénieur chercheur, CEA - INAC, Grenoble Examinateur B. Beaumont Directeur technique, Saint-Gobain LUMILOG, Vallauris Examinateur P. De Mierry Chargé de recherche, CNRS - CRHEA, Valbonne Co-directeur de Thèse P. Vennéguès Ingénieur de recherche, CNRS - CRHEA, Valbonne Directeur de Thèse Centre de Recherche sur l’Hétéroépitaxie et ses Applications , Centre National de la Recherche Scientifique, Sophia Antipolis - Valbonne 2 Résumé Résumé Ingénierie des défauts cristallins pour l’obtention de GaN semi -polaire hétéroépitaxié de haute qualité en vue d’applications optoélectroniques Les matériaux semi-conducteurs III-N sont à l’origine d’une véritable révolution technologique. Qui au jourd’hui n’a pas entendu parler ou n’a pas utilisé des dispositifs optoélectroniques composés de diodes électroluminescentes ou lasers de différentes couleurs ? Malgré l’effervescence autour de ces sources lumineuses (bleu notamment), leurs performances dans le vert et l’ultraviolet demeurent limitées. La principale raison à cela est l’orientation cristalline (0001) III-N (dite polaire) selon laquelle ces matériaux sont généralement épitaxiés et qui induit de forts effets de polarisation. Ces effets peuven t cependant être fortement atténués par l’utilisation d’orientations de croissance dite semi -polaires. Malheureusement, les films de GaN semi-polaires hétéroépitaxiés présentent des densités de défauts très importantes ce qui freine très fortement leur utilisation. L’enjeu de cette thèse de doctorat est de réaliser des films de GaN semi -polaire (11-22) de haute qualité cristalline sur un substrat de saphir en utilisant la technique d’épitaxie en phase vapeur au x organométalliques. La réduction de la densi té de défaut étant l’objectif majeur, différentes méthodes d’ingénieries de défauts s’appuyant sur la structuration de la surface des substrats et sur la croissance sélective du GaN, ont été développées. En parallèle, des études combinant cathodoluminescence et microscopie électronique à transmission ont permis de mettre en évidence les défauts structuraux générés lors de l’hétéroépitaxie , mais surtout d’en comprendre le comportement af in d’être en mesure de les annihiler. Grace à une ingénierie fine et à l’optimisation des procédés de croissance, les densités de défauts obtenues ont permis d’établir de l’état l’art actuel du GaN semi-polaire hétéroépitaxié. La reproductibilité de ces résultats a rendu possible la fabrication de pseudo-substrats 2 pouces de GaN semi-polaire (11-22)GaN de haute qualité, constituant ainsi une plateforme idéale aux futurs dispositifs optoélectroniques semi-polaires. Par la suite, dans le but d’améliorer les performances des diodes électroluminescentes vertes, une étude prélim inaire dédiée à l’optimisation de leur zone active, et plus précisément aux puits quantiques semi-polaires InGaN / GaN, a été menée. D’autre part, au cours de cette thèse, le développement de substrats autosupportés de GaN semi - polaires, ainsi que la confection de cristaux 3D de grande taille (200 µm de largeur) dont la qualité cristalline est comparable aux cristaux de GaN massifs ont été démontrés. Ces deux approches représentent aujourd’hui de nouvelles voies à explorer pour s’approcher encore plus de l a situation idéale que serait l’homoépitaxie. Mots-clefs : Semi-conducteurs III-V, nitrure de gallium, semi-polaire, épitaxie, EPVOM, cathodoluminescence, croissance sélective, diode électroluminescente. 3 4 Abstract Abstract Defect engineering applied to the development of high quality heteroepitaxial semipolar GaN for optoelectronic applications Nitride based materials are the source of disruptive technologies. Nowadays, everyone has heard of or used optoelectronic devices made of light emitting diodes or laser diodes of different colors. Despite the technological turmoil generated by these light sources (blue in particular), their efficiency for green or ultraviolet emission is still limited. For these applications, the main issue to address is related to strong polarization effects due to the (0001) III-N crystal growth orientation (polar orientation). Nevertheless these effects can be drastically decreased using semipolar growth orientations. Unfortunately semipolar heteroepitaxial films contain very high defect densities which hamper their adoption for the time being. The aim of this doctoral thesis is to achieve semipolar (11-22) GaN of high crystal quality on sapphire substrate by metalorganic chemical vapor deposition. Defect reduction being the main objective, several defect engineering methods based on sapphire substrate patterning and GaN selective area growth have been developed. In parallel, studies combining characterization techniques such as cathodoluminescence and transmission electron microscopy have highlighted the structural defects generated during heteroepitaxial growth, and most importantly have provided an insight into how they behave in order to lead to their annihilation. Thanks to refined engineering processes and growth condition optimizations, the remaining defect densities have been reduced to a level that establishes the current state of the art in semipolar heteroepitaxial GaN. The reproducibly of these results has enabled the achievement of high quality 2 inches semipolar (11- 22) GaN templates, thus forming an ideal platform for the growth of the forthcoming semipolar optoelectronic devices. With this in mind, in order to improve green light emitting diodes efficiency, a preliminary study dedicated to the optimization of their active region, and more precisely of the semipolar InGaN/ GaN quantum wells, has been conducted. Finally, the development of semipolar GaN freestanding substrate has been performed, and beyond, the realization of large size (200 µm wide) crystals with a structural quality similar to that of bulk GaN has been successfully demonstrated. These last two approaches pave the way to quasi-homoepitaxial growth of semipolar structures. Keywords: III-V semiconductors, gallium nitride, semipolar, epitaxy, MOCVD, cathodoluminescence, selective area growth, light emitting diode. 5 6 Remerciements Remerciements Je remercie tout d’abord Jean -Yves Duboz, Directeur du CRHEA-CNRS de m’avoir accueilli au sein de ce laboratoire pour la réalisation de ce doctorat. Je remercie ensuite Nicolas Grandjean, Professeur à l’ EPFL, et Thierry Baron, Directeur de recherche au LTM, pour l’honneur qu’ils m’ont fait en acceptant d’être rapporteur s de ce manuscrit. Merci également à Eva Monroy, Ingénieur-chercheur du CEA-INAC, qui a présidé le jury de thèse. Je tiens aussi à remercier particulièrement Bernard Beaumont, Directeur technique de Saint Gobain - LUMILOG, d’être examinateur de ce travail , ainsi que d’ avoir suivi les avancées de mes recherches et apporté un regard d’une grande perspicacité sur mes trava ux. Je souhaiterais par la même occasion remercier Saint Gobain - LUMILOG pour le parrainage de ma bourse de doctorat. Mes plus sincères remerciements vont à Philippe Vennéguès et Philippe de Mierry, directeur et co-directeur de cette thèse, pour leur disponibilité, leur patience et leur confiance sans faille tout au long de ces 3 années et sans qui cette thèse n’aurait pu aboutir. Philippe de Mierry, tu as su me faire partager ton expérience unique de la croissance MOCVD et ta connaissance des nitrures. J’ai particulièrement apprécié tes qualités humaines et travailler à tes cotés au cours de ce travail de thèse a été un réel plaisir. Philippe Vennéguès, je te remercie de m’avoir formé à la recherche avec pédagogie ainsi que pour toutes les images TEM que tu as effectué pour cette thèse. Ta science des défauts, tes idées originales et tes randonnées VTT (non moins originales) ont grandement contribuées à la qualité des résultats obtenus. Merci à Jesús Zúñiga-Pérez et Guy
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