Raman scattering and electrical characterization of AlGaAs/GaAs rectangular and triangular barriers grown by MOCVD

It presents the structural and electrical characterization of rectangular and triangular barriers based on AlxGa1- xAs/GaAs heterostructures grown in a metallic-arsenic-based-MOCVD system. The gallium and aluminum precursors were the organmetallic compounds trimethylgallium and trimethylaluminum, re...

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Detalles Bibliográficos
Autores: J. Díaz-Reyes, M. Galván-Arellano, R. Peña-Sierra
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:México
Institución:Instituto Politécnico Nacional
Repositorio:Redalyc-IPN
OAI Identifier:oai:redalyc.org:94215036003
Acceso en línea:https://www.redalyc.org/articulo.oa?id=94215036003
Access Level:acceso abierto
Palabra clave:Física, Astronomía y Matemáticas
GaAs
MOCVD
Barrier height
Semiconductors III
Raman spectroscopy
Descripción
Sumario:It presents the structural and electrical characterization of rectangular and triangular barriers based on AlxGa1- xAs/GaAs heterostructures grown in a metallic-arsenic-based-MOCVD system. The gallium and aluminum precursors were the organmetallic compounds trimethylgallium and trimethylaluminum, respectively. The barriers were grown with different aluminum concentrations for varying the AlGaAs bandgap and as consequence the potential barrier height. To obtain the triangular barriers increased the Al concentration gradually each minute up to reach 40% molar fraction. Raman spectroscopy was used to the structural characterization of the barriers. Potential barrier height and carrier transport mechanism through them is obtained by the current-voltage measurements. Raman spectra of the rectangular barrier present the TO GaAs-like, LO GaAs-like and LO AlAslike as main vibrational modes. As the growth temperature is increased the layers compensation decreases but theRaman spectra show that the layers become more defective. The triangular barriers Raman spectra presented the same vibrational modes. As the Al concentration is increased the Triangular barriers phononic bands shifted slightly to lower wavenumbers and are broader compared with the phononic bands of the rectangular barriers.