In this thesis I present a study of nanowires, and, in particular, I apply EBIC microscopy for investigation of their electro-optical properties. First, I describe details of the EBIC analytical technique together with a brief historical overview of the electron microscopy, the physical principles of the EBIC, its space resolution, parameters defining the signal amplitude, and the information we can acquire concerning defects, electric fields, etc. Then I focus on the characterization of LEDs based on GaN nanowires, which were analyzed in a cross-section and in a top view configurations. The EBIC measurements were correlated with micro-electroluminescence mapping. Further, I address the fabrication and measurement of nanowire-based InGaN/GaN LEDs detached from their original substrate. I present the EBIC measurements of individual nanowires either cut from their substrate and contacted in a planar geometry or kept standing on supphire substrate and cleaved to reveal the horizontal cross-section.The next part of this thesis is dedicated to an EBIC study of irregular Si nanowire array-based solar cells, and then of the regular nanowire array devices. The current generation was analyzed on a submicrometer scale. Finally, I discuss the fabrication and EBIC measurements of GaN nanowires grown on Si substrate. In particular, I show that the p-n junction was induced in the Si substrate by Al atom diffusion during the nanowire growth. / Dans cette thèse je me propose d’étudier des nano-fils, et en particulier d’utiliser la technique EBIC pour explorer leurs propriétés électro-optiques. Je décris d’abord les détails de la technique d’analyse EBIC avec un bref retour historique sur la microscopie électronique, le principe physique de l’EBIC, sa résolution spatiale, les paramètres conditionnant l’amplitude du signal, et les informations que l’on peut en tirer sur le matériau en termes de défauts, champ électrique, etc. Je m’intéresse ensuite à la caractérisation de LEDs à nano-fils à base de GaN, qui ont été observés par EBIC, soit en coupe soit en vue plane (depuis le haut des fils). Les mesures EBIC sont comparées à celles de micro-électroluminescence. Plus loin j’adresse la fabrication et la mesure de nano-fils à base de GaN séparés de leur substrat d’origine. Je présente les mesures EBIC de nano-fils uniques entiers, puis de nano-fils en coupe horizontale.La partie suivante de la thèse traite d’étude EBIC des cellules solaires à base de nano-fils Si ayant d’abord une géométrie aléatoire, puis une géométrie régulière. La génération de courant dans ces cellules solaires est analysée à l’échelle submicronique. A la fin du manuscrit je discute la fabrication et les mesures EBIC de fils GaN épitaxiés sur Si. Je montre en particulier qu’une jonction p-n est enduite dans le substrat Si par la diffusion d’Al lors de la croissance de nanofils.

Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-03-10T19:12:54Z No. of bitstreams: 1 MAURO MASSANORI MIYASHIRO.pdf: 2380997 bytes, checksum: fc2d550825d50d0a996842532845e496 (MD5) / Made available in DSpace on 2017-03-10T19:12:54Z (GMT). No. of bitstreams: 1 MAURO MASSANORI MIYASHIRO.pdf: 2380997 bytes, checksum: fc2d550825d50d0a996842532845e496 (MD5) Previous issue date: 2017-02-09 / Light Emmiting Diode ? LED. Efici?ncia energ?tica. Portaria n? 144/2015. INMETRO. Fator de pot?ncia. Fluxo luminoso. Efici?ncia energ?tica. The objective of this study was to evaluate the energy efficiency of LED light bulbs (Light Emitting Diode) commercialized in the Brazilian market in the period of 2015/2016 and the development of a low cost test system to measure the mains voltage, current, consumption and power factor of LED lamp. For the evaluation of the LED lamps, the equipment available in the laboratories of the Eldorado Research Institute was used, and as a reference, the requirements established by Ordinance No. 144/2015 of the Instituto Nacional de Metrologia, Qualidade e Tecnologia - INMETRO, published on March 13, 2015. This Ordinance made it mandatory for manufacturers and importers to certify LED bulbs as of February 26, 2016. In order to carry out this work, a set of LED lamps from different manufacturers was acquired in the retail market to be subjected to functional tests of consumption of energy (watts), power factor (PF), luminous flux (lumens) and luminous efficiency (lumens/watt). The data obtained were compared with the nominal values declared by the manufacturers, as specified in the INMETRO ordinance. The results show that 11% of the samples failed in the energy consumption test and 83% failed in the power factor test. The developed test system was validated comparing its measurements with the results obtained in the tests carried out in INMETRO certified laboratory. Through this work it was possible to have an overview of the energy efficiency of LED bulbs currently commercialized in the country. / O presente trabalho teve como objetivo avaliar a efici?ncia energ?tica de l?mpadas com tecnologia LED (Light Emitting Diode) comercializadas no mercado brasileiro no per?odo de 2015/2016 e o desenvolvimento de um sistema de teste de baixo custo para medir a tens?o da rede el?trica, a corrente, o consumo e o fator de pot?ncia de l?mpada LED. Para a avalia??o das l?mpadas LED foram utilizados os equipamentos dispon?veis nos laborat?rios do Instituto de Pesquisas Eldorado e como refer?ncia os requisitos estabelecidos pela Portaria n? 144/2015 do Instituto Nacional de Metrologia, Qualidade e Tecnologia - INMETRO, publicada em 13 de mar?o de 2015. Esta Portaria tornou obrigat?ria para fabricantes e importadores a certifica??o das l?mpadas LED a partir de 26 de fevereiro de 2016. Para a realiza??o deste trabalho foi adquirido no mercado de varejo um conjunto de l?mpadas LED de diferentes fabricantes para serem submetidos a testes funcionais de consumo de energia (watts), fator de pot?ncia (FP), fluxo luminoso (lumens) e efici?ncia luminosa (lumens/watt). Os dados obtidos foram comparados com os valores nominais declarados pelos fabricantes conforme especificado na portaria do INMETRO. Os resultados demonstram que 11% das amostras falharam no teste de consumo de energia e 83% falharam no teste de fator de pot?ncia. O sistema de teste desenvolvido foi validado comparando suas medi??es com os resultados obtidos nos testes realizados em laborat?rio certificado pelo INMETRO. Atrav?s deste trabalho foi poss?vel ter um panorama amostral da efici?ncia energ?tica das l?mpadas LED comercializadas atualmente no pa?s.