Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer
Autor(a) principal: | |
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Data de Publicação: | 2017 |
Outros Autores: | , , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/1822/47699 |
Resumo: | Raman spectroscopy, with both resonant and non-resonant excitation, and infra-red (IR) spectroscopy, in the attenuated total reflection (ATR) configuration, was employed to study lattice vibration modes in a set of carbon-doped GaN (GaN:C) epilayers grown by metalorganic vapour phase epitaxy (MOVPE). We analyse Raman and IR-ATR spectra from the point of view of possible effects of the carbon doping, namely: (i) local vibration mode of C atom in a N sublattice (whose frequency we theoretically estimate as 768 cm-1 using an isotope defect model), and (ii) shift in the positions of longitudinal modes owing to the phonon-plasmon coupling. We find only some indirect hints of the doping effect on the resonant Raman spectra. However, we show theoretically and confirm experimentally that the IR-ATR spectroscopy can be a much more sensitive tool for this purpose, at least for the considered structures. A weak perturbation of the dielectric function of GaN:C, caused by the substitutional carbon impurity, is shown to produce a measurable dip in the ATR reflectivity spectra at ≈ 770 cm-1, for both p- and s-polarizations. Moreover, it influences a specific (guided-wave-type) mode observed at ≈ 737 cm-1, originating from the GaN layer, which appears in the narrow frequency window where the real parts of the two components of the dielectric tensor of the hexagonal crystal have the opposite signs. This interpretation is supported by our modelling of the whole multilayer structure using a transfer matrix formalism. |
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Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layerRaman spectroscopyATR-IR spectroscopyPhononPolaritonCarbon dopingGallium nitrideCiências Naturais::Ciências FísicasScience & TechnologyRaman spectroscopy, with both resonant and non-resonant excitation, and infra-red (IR) spectroscopy, in the attenuated total reflection (ATR) configuration, was employed to study lattice vibration modes in a set of carbon-doped GaN (GaN:C) epilayers grown by metalorganic vapour phase epitaxy (MOVPE). We analyse Raman and IR-ATR spectra from the point of view of possible effects of the carbon doping, namely: (i) local vibration mode of C atom in a N sublattice (whose frequency we theoretically estimate as 768 cm-1 using an isotope defect model), and (ii) shift in the positions of longitudinal modes owing to the phonon-plasmon coupling. We find only some indirect hints of the doping effect on the resonant Raman spectra. However, we show theoretically and confirm experimentally that the IR-ATR spectroscopy can be a much more sensitive tool for this purpose, at least for the considered structures. A weak perturbation of the dielectric function of GaN:C, caused by the substitutional carbon impurity, is shown to produce a measurable dip in the ATR reflectivity spectra at ≈ 770 cm-1, for both p- and s-polarizations. Moreover, it influences a specific (guided-wave-type) mode observed at ≈ 737 cm-1, originating from the GaN layer, which appears in the narrow frequency window where the real parts of the two components of the dielectric tensor of the hexagonal crystal have the opposite signs. This interpretation is supported by our modelling of the whole multilayer structure using a transfer matrix formalism.This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Financing UID/FIS/04650/2013 and Infineon Technologies Austria AG.info:eu-repo/semantics/publishedVersionIOP PublishingUniversidade do MinhoCerqueira, M. F.Vieira, L. G.Alves, A.Correia, R.Huber, M.Andreev, A.Bonanni, A.Vasilevskiy, Mikhail20172017-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/1822/47699engJournal of Physics D: Applied Physics 50, 365103 (2017)0022-37271361-646310.1088/1361-6463/aa7c4bhttps://doi.org/10.1088/1361-6463/aa7c4binfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-21T12:32:16ZPortal AgregadorONG |
dc.title.none.fl_str_mv |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
title |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
spellingShingle |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer Cerqueira, M. F. Raman spectroscopy ATR-IR spectroscopy Phonon Polariton Carbon doping Gallium nitride Ciências Naturais::Ciências Físicas Science & Technology |
title_short |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
title_full |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
title_fullStr |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
title_full_unstemmed |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
title_sort |
Raman and IR-ATR spectroscopy studies of heteroepitaxial structures with a GaN:C top layer |
author |
Cerqueira, M. F. |
author_facet |
Cerqueira, M. F. Vieira, L. G. Alves, A. Correia, R. Huber, M. Andreev, A. Bonanni, A. Vasilevskiy, Mikhail |
author_role |
author |
author2 |
Vieira, L. G. Alves, A. Correia, R. Huber, M. Andreev, A. Bonanni, A. Vasilevskiy, Mikhail |
author2_role |
author author author author author author author |
dc.contributor.none.fl_str_mv |
Universidade do Minho |
dc.contributor.author.fl_str_mv |
Cerqueira, M. F. Vieira, L. G. Alves, A. Correia, R. Huber, M. Andreev, A. Bonanni, A. Vasilevskiy, Mikhail |
dc.subject.por.fl_str_mv |
Raman spectroscopy ATR-IR spectroscopy Phonon Polariton Carbon doping Gallium nitride Ciências Naturais::Ciências Físicas Science & Technology |
topic |
Raman spectroscopy ATR-IR spectroscopy Phonon Polariton Carbon doping Gallium nitride Ciências Naturais::Ciências Físicas Science & Technology |
description |
Raman spectroscopy, with both resonant and non-resonant excitation, and infra-red (IR) spectroscopy, in the attenuated total reflection (ATR) configuration, was employed to study lattice vibration modes in a set of carbon-doped GaN (GaN:C) epilayers grown by metalorganic vapour phase epitaxy (MOVPE). We analyse Raman and IR-ATR spectra from the point of view of possible effects of the carbon doping, namely: (i) local vibration mode of C atom in a N sublattice (whose frequency we theoretically estimate as 768 cm-1 using an isotope defect model), and (ii) shift in the positions of longitudinal modes owing to the phonon-plasmon coupling. We find only some indirect hints of the doping effect on the resonant Raman spectra. However, we show theoretically and confirm experimentally that the IR-ATR spectroscopy can be a much more sensitive tool for this purpose, at least for the considered structures. A weak perturbation of the dielectric function of GaN:C, caused by the substitutional carbon impurity, is shown to produce a measurable dip in the ATR reflectivity spectra at ≈ 770 cm-1, for both p- and s-polarizations. Moreover, it influences a specific (guided-wave-type) mode observed at ≈ 737 cm-1, originating from the GaN layer, which appears in the narrow frequency window where the real parts of the two components of the dielectric tensor of the hexagonal crystal have the opposite signs. This interpretation is supported by our modelling of the whole multilayer structure using a transfer matrix formalism. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017 2017-01-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/1822/47699 |
url |
http://hdl.handle.net/1822/47699 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Journal of Physics D: Applied Physics 50, 365103 (2017) 0022-3727 1361-6463 10.1088/1361-6463/aa7c4b https://doi.org/10.1088/1361-6463/aa7c4b |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
IOP Publishing |
publisher.none.fl_str_mv |
IOP Publishing |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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