Engenharia de defeitos em semicondutores de gap largo
Autor(a) principal: | |
---|---|
Data de Publicação: | 2015 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFSCAR |
Texto Completo: | https://repositorio.ufscar.br/handle/ufscar/7412 |
Resumo: | Defects play a fundamental issue on physical properties of wide bandgap semiconductors (WBS) due to the possibility of application in high temperature. This work shows the features of the defects in di erent kind of WBS grown/synthesized by solid state reaction, Pechini method and Molecular Beam Epitaxy. First we investigated the structural and optical properties of erbium- and manganese-doped strontium aluminates (SrAl2O4). The fundamental optical transitions due to Er3+ and Mn2+ are typical features of the well-diluted doping process. A signi cant enhancement of the Er3+ optical emission band at 1530 nm was observed when the matrix is co-doped with Mn. A model of energy transfer mechanism from Mn2+ to Er3+ is proposed to explain the experimental results. We present also the e ect of preparation and annealing conditions on the properties of Nb2O5. The increase of oxygen vacancies causes an inrreversible phase transition from pseudohexagonal to orthorhombic phase, and they are responsible for the increase in the e ective magnetic moments related to paramagnetic behavior. Finally, we explore the e ects of the interfaces imperfections of quantum wells of cubic GaN alloys. An indication of localized states in low temperature is observed. A decrease of this e ects happens when we increase the number of interfaces. Furthermore, magneto-PL measurements show a higher spin polarizations in the donor-acceptor impurities in the bulk of c-GaN corroborate for the importance of the defects. This work shows that the defects engineering in WBS are fundametal for developing new technologies in spintronics and optoelectronic eld. |
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Herval, Leonilson Kiyoshi Sato deGodoy, Marcio Peron Franco dehttp://lattes.cnpq.br/2609654784637427http://lattes.cnpq.br/5725850954671583aa226974-fdd2-4e22-be1e-2803c1dd1a172016-09-23T18:36:47Z2016-09-23T18:36:47Z2015-12-14HERVAL, Leonilson Kiyoshi Sato de. Engenharia de defeitos em semicondutores de gap largo. 2015. Tese (Doutorado em Física) – Universidade Federal de São Carlos, São Carlos, 2015. Disponível em: https://repositorio.ufscar.br/handle/ufscar/7412.https://repositorio.ufscar.br/handle/ufscar/7412Defects play a fundamental issue on physical properties of wide bandgap semiconductors (WBS) due to the possibility of application in high temperature. This work shows the features of the defects in di erent kind of WBS grown/synthesized by solid state reaction, Pechini method and Molecular Beam Epitaxy. First we investigated the structural and optical properties of erbium- and manganese-doped strontium aluminates (SrAl2O4). The fundamental optical transitions due to Er3+ and Mn2+ are typical features of the well-diluted doping process. A signi cant enhancement of the Er3+ optical emission band at 1530 nm was observed when the matrix is co-doped with Mn. A model of energy transfer mechanism from Mn2+ to Er3+ is proposed to explain the experimental results. We present also the e ect of preparation and annealing conditions on the properties of Nb2O5. The increase of oxygen vacancies causes an inrreversible phase transition from pseudohexagonal to orthorhombic phase, and they are responsible for the increase in the e ective magnetic moments related to paramagnetic behavior. Finally, we explore the e ects of the interfaces imperfections of quantum wells of cubic GaN alloys. An indication of localized states in low temperature is observed. A decrease of this e ects happens when we increase the number of interfaces. Furthermore, magneto-PL measurements show a higher spin polarizations in the donor-acceptor impurities in the bulk of c-GaN corroborate for the importance of the defects. This work shows that the defects engineering in WBS are fundametal for developing new technologies in spintronics and optoelectronic eld.Os defeitos em semicondutores acarretam mudanças nas propriedades físicas do material, tendo uma grande importância nos semicondutores que possuem alta energia de gap devido à possibilidade de aplicação em alta temperatura. No presente trabalho, estudamos as características atribuídas à presença de defeitos em diferentes semicondutores de gap largo, crescidos/sintetizados por reação de estado sólido, método de Pechini e epitaxia de feixes moleculares. Primeiramente, investigamos as propriedades ópticas e estruturais do aluminato de estrôncio (SrAl2O4) dopado com érbio e co-dopado com manganês. Neste caso, um aumento na emissão do Er3+ na região do infravermelho (1530 nm) foi observado na matriz com co-dopagem de manganês. Atribuímos este efeito ao mecanismo de transferência de energia do íon de Mn2+ para o Er3+. Também estudamos os efeitos das condições de preparação e tratamento térmico nas propriedades de pentóxido de nióbio (Nb2O5). Nossa investigação, mostra que vacâncias de oxigênio causam transições irreversíveis da fase pseudo-hexagonal para a ortorrômbica. Além disso, esses defeitos são responsáveis por um acréscimo de momentos magnéticos efetivos, relacionados com o comportamento paramagnético. Por último, averiguamos os efeitos de imperfeições entre as interfaces de poços quânticos de ligas de nitreto de gálio cúbico (cGaN). Esse estudo indicou uma diminuição de estados localizados, em baixa temperatura, com a mudança na quantidade de interfaces do QW. No caso do c GaN bulk, foi observado uma maior polarização de spin na emissão óptica da impureza doadora-aceitadora. Este trabalho evidencia a importância da engenharia de defeitos em semicondutores de gap largo para o aperfeiçoamento de tecnologias ligadas à área de optoeletrônica e spintrônica.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)porUniversidade Federal de São CarlosCâmpus São CarlosPrograma de Pós-Graduação em Física - PPGFUFSCarEngenharia de defeitosSemicondutoresAluminato de Estrôncio (SrAl2O4)Amplificadores ópticosSrAl2OOptical amplifierDilute magnetic semiconductorsNb2O5CIENCIAS EXATAS E DA TERRA::FISICAEngenharia de defeitos em semicondutores de gap largoinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisOnline600600de7ee5a7-6d94-42d5-96b1-bb4d5a1496adinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFSCARinstname:Universidade Federal de São Carlos (UFSCAR)instacron:UFSCARORIGINALTeseLKSH.pdfTeseLKSH.pdfapplication/pdf62711757https://repositorio.ufscar.br/bitstream/ufscar/7412/1/TeseLKSH.pdfdd2b481497af4493346131729910c613MD51LICENSElicense.txtlicense.txttext/plain; charset=utf-81957https://repositorio.ufscar.br/bitstream/ufscar/7412/2/license.txtae0398b6f8b235e40ad82cba6c50031dMD52TEXTTeseLKSH.pdf.txtTeseLKSH.pdf.txtExtracted texttext/plain177238https://repositorio.ufscar.br/bitstream/ufscar/7412/3/TeseLKSH.pdf.txt9777993f78436dad0e0c20e18b641835MD53THUMBNAILTeseLKSH.pdf.jpgTeseLKSH.pdf.jpgIM Thumbnailimage/jpeg4130https://repositorio.ufscar.br/bitstream/ufscar/7412/4/TeseLKSH.pdf.jpg5c37542667b8e8cdd1382749219cdc47MD54ufscar/74122023-09-18 18:30:49.447oai:repositorio.ufscar.br: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Repositório InstitucionalPUBhttps://repositorio.ufscar.br/oai/requestopendoar:43222023-09-18T18:30:49Repositório Institucional da UFSCAR - Universidade Federal de São Carlos (UFSCAR)false |
dc.title.por.fl_str_mv |
Engenharia de defeitos em semicondutores de gap largo |
title |
Engenharia de defeitos em semicondutores de gap largo |
spellingShingle |
Engenharia de defeitos em semicondutores de gap largo Herval, Leonilson Kiyoshi Sato de Engenharia de defeitos Semicondutores Aluminato de Estrôncio (SrAl2O4) Amplificadores ópticos SrAl2O Optical amplifier Dilute magnetic semiconductors Nb2O5 CIENCIAS EXATAS E DA TERRA::FISICA |
title_short |
Engenharia de defeitos em semicondutores de gap largo |
title_full |
Engenharia de defeitos em semicondutores de gap largo |
title_fullStr |
Engenharia de defeitos em semicondutores de gap largo |
title_full_unstemmed |
Engenharia de defeitos em semicondutores de gap largo |
title_sort |
Engenharia de defeitos em semicondutores de gap largo |
author |
Herval, Leonilson Kiyoshi Sato de |
author_facet |
Herval, Leonilson Kiyoshi Sato de |
author_role |
author |
dc.contributor.authorlattes.por.fl_str_mv |
http://lattes.cnpq.br/5725850954671583 |
dc.contributor.author.fl_str_mv |
Herval, Leonilson Kiyoshi Sato de |
dc.contributor.advisor1.fl_str_mv |
Godoy, Marcio Peron Franco de |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/2609654784637427 |
dc.contributor.authorID.fl_str_mv |
aa226974-fdd2-4e22-be1e-2803c1dd1a17 |
contributor_str_mv |
Godoy, Marcio Peron Franco de |
dc.subject.por.fl_str_mv |
Engenharia de defeitos Semicondutores Aluminato de Estrôncio (SrAl2O4) Amplificadores ópticos SrAl2O |
topic |
Engenharia de defeitos Semicondutores Aluminato de Estrôncio (SrAl2O4) Amplificadores ópticos SrAl2O Optical amplifier Dilute magnetic semiconductors Nb2O5 CIENCIAS EXATAS E DA TERRA::FISICA |
dc.subject.eng.fl_str_mv |
Optical amplifier Dilute magnetic semiconductors Nb2O5 |
dc.subject.cnpq.fl_str_mv |
CIENCIAS EXATAS E DA TERRA::FISICA |
description |
Defects play a fundamental issue on physical properties of wide bandgap semiconductors (WBS) due to the possibility of application in high temperature. This work shows the features of the defects in di erent kind of WBS grown/synthesized by solid state reaction, Pechini method and Molecular Beam Epitaxy. First we investigated the structural and optical properties of erbium- and manganese-doped strontium aluminates (SrAl2O4). The fundamental optical transitions due to Er3+ and Mn2+ are typical features of the well-diluted doping process. A signi cant enhancement of the Er3+ optical emission band at 1530 nm was observed when the matrix is co-doped with Mn. A model of energy transfer mechanism from Mn2+ to Er3+ is proposed to explain the experimental results. We present also the e ect of preparation and annealing conditions on the properties of Nb2O5. The increase of oxygen vacancies causes an inrreversible phase transition from pseudohexagonal to orthorhombic phase, and they are responsible for the increase in the e ective magnetic moments related to paramagnetic behavior. Finally, we explore the e ects of the interfaces imperfections of quantum wells of cubic GaN alloys. An indication of localized states in low temperature is observed. A decrease of this e ects happens when we increase the number of interfaces. Furthermore, magneto-PL measurements show a higher spin polarizations in the donor-acceptor impurities in the bulk of c-GaN corroborate for the importance of the defects. This work shows that the defects engineering in WBS are fundametal for developing new technologies in spintronics and optoelectronic eld. |
publishDate |
2015 |
dc.date.issued.fl_str_mv |
2015-12-14 |
dc.date.accessioned.fl_str_mv |
2016-09-23T18:36:47Z |
dc.date.available.fl_str_mv |
2016-09-23T18:36:47Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
HERVAL, Leonilson Kiyoshi Sato de. Engenharia de defeitos em semicondutores de gap largo. 2015. Tese (Doutorado em Física) – Universidade Federal de São Carlos, São Carlos, 2015. Disponível em: https://repositorio.ufscar.br/handle/ufscar/7412. |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufscar.br/handle/ufscar/7412 |
identifier_str_mv |
HERVAL, Leonilson Kiyoshi Sato de. Engenharia de defeitos em semicondutores de gap largo. 2015. Tese (Doutorado em Física) – Universidade Federal de São Carlos, São Carlos, 2015. Disponível em: https://repositorio.ufscar.br/handle/ufscar/7412. |
url |
https://repositorio.ufscar.br/handle/ufscar/7412 |
dc.language.iso.fl_str_mv |
por |
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por |
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600 600 |
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de7ee5a7-6d94-42d5-96b1-bb4d5a1496ad |
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info:eu-repo/semantics/openAccess |
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openAccess |
dc.publisher.none.fl_str_mv |
Universidade Federal de São Carlos Câmpus São Carlos |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Física - PPGF |
dc.publisher.initials.fl_str_mv |
UFSCar |
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Universidade Federal de São Carlos Câmpus São Carlos |
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