Influence of Si(110) misoriented substrates on the microstructure and photoreflectance of GaAs thin films deposited by MBE

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Main Author:	M. A. Vidal
Format:	Artículo científico
Language:	en
Published:	Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C. 2000
Subjects:	Física, Astronomía y Matemáticas MBE Ray GaAs on Si heterostructures photoreflectance
Online Access:	Acceder al recurso
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author	M. A. Vidal
author_facet	M. A. Vidal
contents	Influence of Si(110) misoriented substrates on the microstructure and photoreflectance of GaAs thin films deposited by MBE M. A. Vidal J. Luyo Alvarado M. López López M. Meléndez Lira Física, Astronomía y Matemáticas MBE Ray GaAs on Si heterostructures photoreflectance We have grown GaAs layers by molecular beam epitaxy on Si(110) substrates with different tilted angles towards the[001] direction. The samples where characterized by atomic force microscopy (AFM), high resolution x-ray diffraction(HRXRD), and photoreflectance spectroscopy (PR). The surface morphology analysis by AFM showed that the surfaceroughness decreased as the off-angle increased. The dislocation density was obtained from the full width at half maximumof the HRXRD reflection peaks. By increasing the off-angle we observed a reduction in the dislocation density. The PRspectra showed the presence of oscillations above the band-gap energy value associated to built-in internal electric fields.The built-in electric field strength and the GaAs band-gap energy values were obtained by employing the Franz-Keldyshmodel. We obtained band-gap energy values that suggest the presence of residual strains in the films 2000 artículo científico 1665-3521 https://www.redalyc.org/articulo.oa?id=94201009 en http://www.redalyc.org/revista.oa?id=942 Superficies y vacío application/pdf Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C. Superficies y vacío (México) Num.10
format	Artículo científico
id	redalyc_94201009
language	en
publishDate	2000
publisher	Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C.
spellingShingle	Influence of Si(110) misoriented substrates on the microstructure and photoreflectance of GaAs thin films deposited by MBE M. A. Vidal Física, Astronomía y Matemáticas MBE Ray GaAs on Si heterostructures photoreflectance Influence of Si(110) misoriented substrates on the microstructure and photoreflectance of GaAs thin films deposited by MBE M. A. Vidal J. Luyo Alvarado M. López López M. Meléndez Lira Física, Astronomía y Matemáticas MBE Ray GaAs on Si heterostructures photoreflectance We have grown GaAs layers by molecular beam epitaxy on Si(110) substrates with different tilted angles towards the[001] direction. The samples where characterized by atomic force microscopy (AFM), high resolution x-ray diffraction(HRXRD), and photoreflectance spectroscopy (PR). The surface morphology analysis by AFM showed that the surfaceroughness decreased as the off-angle increased. The dislocation density was obtained from the full width at half maximumof the HRXRD reflection peaks. By increasing the off-angle we observed a reduction in the dislocation density. The PRspectra showed the presence of oscillations above the band-gap energy value associated to built-in internal electric fields.The built-in electric field strength and the GaAs band-gap energy values were obtained by employing the Franz-Keldyshmodel. We obtained band-gap energy values that suggest the presence of residual strains in the films 2000 artículo científico 1665-3521 https://www.redalyc.org/articulo.oa?id=94201009 en http://www.redalyc.org/revista.oa?id=942 Superficies y vacío application/pdf Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C. Superficies y vacío (México) Num.10
title	Influence of Si(110) misoriented substrates on the microstructure and photoreflectance of GaAs thin films deposited by MBE
topic	Física, Astronomía y Matemáticas MBE Ray GaAs on Si heterostructures photoreflectance
url	https://www.redalyc.org/articulo.oa?id=94201009

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