Hostname: page-component-8448b6f56d-gtxcr Total loading time: 0 Render date: 2024-04-17T23:57:05.370Z Has data issue: false hasContentIssue false
  • English
  • Français

Quantitative Chemical Mapping of InGaN Quantum Wells from Calibrated High-Angle Annular Dark Field Micrographs

Published online by Cambridge University Press:  30 June 2015

Daniel Carvalho ,
Francisco M. Morales ,
Teresa Ben ,
Rafael García ,
Andrés Redondo-Cubero ,
Eduardo Alves ,
Katharina Lorenz ,
Paul R. Edwards ,
Kevin P. O’Donnell  and
Christian Wetzel
Daniel Carvalho*
Affiliation:
Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain IMEYMAT: Institute of Research on Electron Microscopy and Materials of the University of Cádiz, Spain
Francisco M. Morales
Affiliation:
Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain IMEYMAT: Institute of Research on Electron Microscopy and Materials of the University of Cádiz, Spain
Teresa Ben
Affiliation:
Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain IMEYMAT: Institute of Research on Electron Microscopy and Materials of the University of Cádiz, Spain
Rafael García
Affiliation:
Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, Universidad de Cádiz, Cádiz, Spain IMEYMAT: Institute of Research on Electron Microscopy and Materials of the University of Cádiz, Spain
Andrés Redondo-Cubero
Affiliation:
IPFN, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, km 139.7, 2695-066 Bobadela LRS, Portugal Departamento de Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid, Spain
Eduardo Alves
Affiliation:
IPFN, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, km 139.7, 2695-066 Bobadela LRS, Portugal
Katharina Lorenz
Affiliation:
IPFN, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, km 139.7, 2695-066 Bobadela LRS, Portugal
Paul R. Edwards
Affiliation:
SUPA Department of Physics, University of Strathclyde, Glasgow, G4 0NG, Scotland, UK
Kevin P. O’Donnell
Affiliation:
SUPA Department of Physics, University of Strathclyde, Glasgow, G4 0NG, Scotland, UK
Christian Wetzel
Affiliation:
Department of Physics and Future Chips Constellation, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
*
*Corresponding author. daniel.carvalho@uca.es
Get access

Abstract

We present a simple and robust method to acquire quantitative maps of compositional fluctuations in nanostructures from low magnification high-angle annular dark field (HAADF) micrographs calibrated by energy-dispersive X-ray (EDX) spectroscopy in scanning transmission electron microscopy (STEM) mode. We show that a nonuniform background in HAADF-STEM micrographs can be eliminated, to a first approximation, by use of a suitable analytic function. The uncertainty in probe position when collecting an EDX spectrum renders the calibration of HAADF-STEM micrographs indirect, and a statistical approach has been developed to determine the position with confidence. Our analysis procedure, presented in a flowchart to facilitate the successful implementation of the method by users, was applied to discontinuous InGaN/GaN quantum wells in order to obtain quantitative determinations of compositional fluctuations on the nanoscale.

Keywords

InGaNHAADF-STEMEDXRBSchemical quantification
Type
Materials Applications and Techniques
Information
Microscopy and Microanalysis , Volume 21 , Issue 4 , August 2015 , pp. 994 - 1005
Copyright
© Microscopy Society of America 2015 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Barradas, N.P. & Jeynes, C. (2008). Advanced physics and algorithms in the IBA DataFurnace. Nucl Instrum Methods Phys Res B 266(8), 1875–1879.CrossRefGoogle Scholar
Cazaux, J. (1995). Correlations between ionization radiation damage and charging effects in transmission electron microscopy. Ultramicroscopy 60(3), 411–425.Google Scholar
Crewe, A.V., Wall, J. & Langmore, J. (1970). Visibility of single atoms. Science 168(3937), 1338–1340.Google Scholar
Detchprohm, T., Zhu, M., Xia, Y., Li, Y., Zhao, W., Senawiratne, J. & Wetzel, C. (2008). Improved performance of GaInN based deep green light emitting diodes through V-defect reduction. Physica Status Solidi (c) 5(6), 2207–2209.Google Scholar
Drouin, D., Couture, A.R., Joly, D., Tastet, X., Aimez, V. & Gauvin, R. (2007). CASINO V2.42 -- A fast and easy-to-use modeling tool for scanning electron microscopy and microanalysis users. Scanning 29(3), 92–101.Google Scholar
Egerton, R.F. (2011). Electron Energy-Loss Spectroscopy in the Electron Microscope. NY, USA: Springer.Google Scholar
Gu, G.H., Park, C.G. & Nam, K.B. (2009). Inhomogeneity of a highly efficient InGaN based blue LED studied by three-dimensional atom probe tomography. Phys Status Solidi Rapid Res Lett 3(4), 100–102.CrossRefGoogle Scholar
Hammersley, S., Badcock, T.J., Watson-Parris, D., Godfrey, M.J., Dawson, P., Kappers, M.J. & Humphreys, C.J. (2011). Study of efficiency droop and carrier localisation in an InGaN/GaN quantum well structure. Phys Status Solidi (C) 8(7–8), 2194–2196.Google Scholar
Hsu, Y.-C., Lo, I., Shih, C.-H., Pang, W.-Y., Hu, C.-H., Wang, Y.-C., Tsai, C.-D., Chou, M.M.C. & Hsu, G.Z.L. (2014). Green light emission by InGaN/GaN multiple-quantum-well microdisks. Appl Phys Lett 104(10), 102105-1--102105-4.Google Scholar
Jesson, D.E. & Pennycook, S.J. (1995). Incoherent imaging of crystals using thermally scattered electrons. Proc R Soc Lond A Math Phys Sci 449(1936), 273–293.Google Scholar
Kim, Y.-M., Jeong, H., Hong, S.-H., Chung, S.-Y., Lee, J. & Kim, Y.-J. (2010). Practical approaches to mitigation of specimen charging in high-resolution transmission electron microscopy. J Anal Sci Technol 1(2), 134–140.Google Scholar
Kisielowski, C., Liliental-Weber, Z. & Nakamura, S. (1997). Atomic scale indium distribution in a GaN/In0.43Ga0.57N/Al0.1Ga0.9N quantum well structure. Jpn J Appl Phys 36, 6932.Google Scholar
Kret, S., Ivaldi, F., Sobczak, K., Czernecki, R. & Leszczyński, M. (2010). Inhomogeneities of InGaN/GaN MOVPE multi quantum wells grown with a two temperatures process studied by transmission electron microscopy. Phys Status Solidi (A) 207(5), 1101–1104.Google Scholar
Lai, Y.-L., Liu, C.-P. & Chen, Z.-Q. (2006). Tuning the emitting wavelength of InGaN/GaN superlattices from blue, green to yellow by controlling the size of InGaN quasi-quantum dot. Thin Solid Films 498(1–2), 128–132.CrossRefGoogle Scholar
Liu, F., Collazo, R., Mita, S., Sitar, Z., Pennycook, S.J. & Duscher, G. (2008). Direct observation of inversion domain boundaries of GaN on c-sapphire at sub-ångstrom resolution. Adv Mater 20(11), 2162–2165.Google Scholar
Mayrock, O., Wünsche, H.J. & Henneberger, F. (2000). Polarization charge screening and indium surface segregation in (In,Ga)N/GaN single and multiple quantum wells. Phys Rev B 62(24), 16870–16880.Google Scholar
Molina, S.I., Sales, D.L., Galindo, P.L., Fuster, D., González, Y., Alén, B., González, L., Varela, M. & Pennycook, S.J. (2009). Column-by-column compositional mapping by Z-contrast imaging. Ultramicroscopy 109(2), 172–176.Google Scholar
Narayan, J., Wang, H., Ye, J., Hon, S.-J., Fox, K., Chen, J.C., Choi, H.K. & Fan, J.C.C. (2002). Effect of thickness variation in high-efficiency InGaN/GaN light-emitting diodes. Appl Phys Lett 81(5), 841–843.Google Scholar
O’Donnell, K.P., Auf der Maur, M., Di Carlo, A. & Lorenz, K., the S.C. (2012). It’s not easy being green: Strategies for all-nitrides, all-colour solid state lighting. Phys Status Solidi Rapid Res Lett 6(2), 49–52.Google Scholar
O’Donnell, K.P., Fernandez-Torrente, I., Edwards, P.R. & Martin, R.W. (2004). The composition dependence of the InxGa1−xN bandgap. J Cryst Growth 269(1), 100–105.Google Scholar
Özdöl, V.B., Koch, C.T. & van Aken, P.A. (2010). A nondamaging electron microscopy approach to map in distribution in InGaN light-emitting diodes. J Appl Phys 108(5), 056103-1--056103-3.Google Scholar
Pantzas, K., Patriarche, G., Troadec, D., Gautier, S., Moudakir, T., Suresh, S., Largeau, L., Mauguin, O., Voss, P.L. & Ougazzaden, A. (2012). Nanometer-scale, quantitative composition mappings of InGaN layers from a combination of scanning transmission electron microscopy and energy dispersive x-ray spectroscopy. Nanotechnology 23(45), 455707.Google Scholar
Pennycook, S.J., Berger, S.D. & Culbertson, R.J. (1986). Elemental mapping with elastically scattered electrons. J Microsc 144(3), 229–249.Google Scholar
Pennycook, S.J., Rafferty, B. & Nellist, P.D. (2000). Z-contrast imaging in an aberration-corrected scanning transmission electron microscope. Microsc Microanal 6(4), 343–352.Google Scholar
Rigutti, L., Blum, I., Shinde, D., Hernández-Maldonado, D., Lefebvre, W., Houard, J., Vurpillot, F., Vella, A., Tchernycheva, M., Durand, C., Eymery, J. & Deconihout, B. (2013). Correlation of microphotoluminescence spectroscopy, scanning transmission electron microscopy, and atom probe tomography on a single nano-object containing an InGaN/GaN multiquantum well system. Nano Lett 14(1), 107–114.Google Scholar
Rosenauer, A., Mehrtens, T., Müller, K., Gries, K., Schowalter, M., Venkata Satyam, P., Bley, S., Tessarek, C., Hommel, D., Sebald, K., Seyfried, M., Gutowski, J., Avramescu, A., Engl, K. & Lutgen, S. (2011 a). Composition mapping in InGaN by scanning transmission electron microscopy. Ultramicroscopy 111(8), 1316–1327.Google Scholar
Rosenauer, A., Thorsten, M., Müller, K., Gries, K., Schowalter, M., Stephanie, B., Parlapalli Venkata, S., Avramescu, A., Karl, E. & Stephan, L. (2011 b). 2D-composition mapping in InGaN without electron beam induced clustering of indium by STEM HAADF Z-contrast imaging. J Phys Conf Ser 326(1), 012040.CrossRefGoogle Scholar
Van den Broek, W., Rosenauer, A., Goris, B., Martinez, G.T., Bals, S., Van Aert, S. & Van Dyck, D. (2012). Correction of non-linear thickness effects in HAADF STEM electron tomography. Ultramicroscopy 116, 8–12.Google Scholar
Verzellesi, G., Saguatti, D., Meneghini, M., Bertazzi, F., Goano, M., Meneghesso, G. & Zanoni, E. (2013). Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies. J Appl Phys 114(7), 071101-1--071101-14.CrossRefGoogle Scholar
Walther, T. (2006). A new experimental procedure to quantify annular dark field images in scanning transmission electron microscopy. J Microsc 221(2), 137–144.Google Scholar
Watson-Parris, D., Godfrey, M.J., Oliver, R.A., Dawson, P., Galtrey, M.J., Kappers, M.J. & Humphreys, C.J. (2010). Energy landscape and carrier wave-functions in InGaN/GaN quantum wells. Phys Status Solidi (C) 7(7–8), 2255–2258.Google Scholar