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Thickness Variations and Absence of Lateral Compositional Fluctuations in Aberration-Corrected STEM Images of InGaN LED Active Regions at Low Dose

Published online by Cambridge University Press:  26 March 2014

Andrew B. Yankovich ,
Alexander V. Kvit ,
Xing Li ,
Fan Zhang ,
Vitaliy Avrutin ,
Huiyong Liu ,
Natalia Izyumskaya ,
Ümit Özgür ,
Brandon Van Leer  and
Hadis Morkoç
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Andrew B. Yankovich*
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin–Madison, Madison, WI 53706, USA
Alexander V. Kvit
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin–Madison, Madison, WI 53706, USA
Xing Li
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Fan Zhang
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Vitaliy Avrutin
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Huiyong Liu
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Natalia Izyumskaya
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Ümit Özgür
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Brandon Van Leer
Affiliation:
FEI Company, Hillsboro, OR 97124, USA
Hadis Morkoç
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
Paul M. Voyles
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin–Madison, Madison, WI 53706, USA
*
*Corresponding author.ayankovich@wisc.edu
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Abstract

Aberration-corrected scanning transmission electron microscopy images of the In0.15Ga0.85N active region of a blue light-emitting diode, acquired at ~0.1% of the electron dose known to cause electron beam damage, show no lateral compositional fluctuations, but do exhibit one to four atomic plane steps in the active layer’s upper boundary. The area imaged was measured to be 2.9 nm thick using position averaged convergent beam electron diffraction, ensuring the sample was thin enough to capture compositional variation if it was present. A focused ion beam prepared sample with a very large thin area provides the possibility to directly observe large fluctuations in the active layer thickness that constrict the active layer at an average lateral length scale of 430 nm.

Keywords

STEMPACBEDFIBInGaNdouble heterostructurelight-emitting diodecompositional variation
Type
Materials Applications
Information
Microscopy and Microanalysis , Volume 20 , Issue 3 , June 2014 , pp. 864 - 868
Copyright
© Microscopy Society of America 2014 

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References

Arif, R.A., Ee, Y.-K. & Tansu, N. (2007). Polarization engineering via staggered InGaN quantum wells for radiative efficiency enhancement of light emitting diodes. Appl Phys Lett 91, 091110.CrossRefGoogle Scholar
Bartel, T.P., Specht, P., Ho, J.C. & Kisielowski, C. (2007). Phase separation in In x Ga 1−x N. Philos Mag 87, 1983–1998.Google Scholar
Cho, H.K., Lee, J.Y., Sharma, N., Humphreys, C.J., Yang, G.M., Kim, C.S., Song, J.H. & Yu, P.W. (2001). Effect of growth interruptions on the light emission and indium clustering of InGaN/GaN multiple quantum wells. Appl Phys Lett 79, 2594.CrossRefGoogle Scholar
Costa, P.M.F.J., Datta, R., Kappers, M.J., Vickers, M.E., Humphreys, C.J., Graham, D.M., Dawson, P., Godfrey, M.J., Thrush, E.J. & Mullins, J.T. (2006). Misfit dislocations in In-rich InGaN/GaN quantum well structures. Phys Status Solidi (a) 203, 1729–1732.Google Scholar
Egerton, R.F. (1996). Electron Energy-Loss Spectroscopy in the Electron Microscope , 2nd ed. New York, USA: Springer.Google Scholar
El-Masry, N.A., Piner, E.L., Liu, S.X. & Bedair, S.M. (1998). Phase separation in InGaN grown by metalorganic chemical vapor deposition. Appl Phys Lett 72, 40–42.Google Scholar
Giannuzzi, L.A. & Stevie, F.A. (2005). Introduction to Focused Ion Beams: Instrumentation, Theory , Techniques and Practice. New York, USA: Springer.CrossRefGoogle Scholar
Hartel, P., Rose, H. & Dinges, C. (1996). Conditions and reasons for incoherent imaging in STEM. Ultramicroscopy 63, 93–114.Google Scholar
Ho, I. & Stringfellow, G.B. (1996). Solid phase immiscibility in GaInN. Appl Phys Lett 69, 2701.CrossRefGoogle Scholar
Humphreys, C.J. (2007). Does In form In-rich clusters in InGaN quantum wells? Philos Mag 87, 1971–1982.Google Scholar
Iakoubovskii, K., Mitsuishi, K., Nakayama, Y. & Furuya, K. (2008). Thickness measurements with electron energy loss spectroscopy. Microsc Res Tech 71, 626–631.Google Scholar
Kirkland, E.J. (1998). Advanced Computing in Electron Microscopy, 1st ed. New York, USA: Springer.Google Scholar
Kret, S., Dłużewski, P., Szczepańska, A., Zak, M., Czernecki, R., Kryśko, M., Leszczyński, M. & Maciejewski, G. (2007). Homogenous indium distribution in InGaN/GaN laser active structure grown by LP-MOCVD on bulk GaN crystal revealed by transmission electron microscopy and X-ray diffraction. Nanotechnology 18, 465707.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, 1101–1104.Google Scholar
LeBeau, J.M., D’Alfonso, A.J., Wright, N.J., Allen, L.J. & Stemmer, S. (2011). Determining ferroelectric polarity at the nanoscale. Appl Phys Lett 98, 052904.Google Scholar
LeBeau, J.M., Findlay, S.D., Allen, L.J. & Stemmer, S. (2010). Position averaged convergent beam electron diffraction: Theory and applications. Ultramicroscopy 110, 118–125.Google Scholar
Li, X., Liu, H.Y., Liu, S., Ni, X., Wu, M., Avrutin, V., Izyumskaya, N., Özgür, Ü. & Morkoç, H. (2010). InGaN based light emitting diodes with Ga doped ZnO as transparent conducting oxide. Phys Status Solidi (a) 207, 1993–1996.Google Scholar
Mutta, G.R., Ruterana, P., Doualan, J.L., Chauvat, M.P., Ivaldi, F., Kret, S., Kaufmann, N.A.K., Dussaigne, A., Martin, D. & Grandjean, N. (2011). Investigation of the In composition in InGaN/GaN quantum wells deposited by MOVPE and/or MBE with emission from violet to green. Phys Status Solidi (b) 248, 1187–1190.CrossRefGoogle Scholar
Narukawa, Y., Kawakami, Y., Funato, M., Fujita, S., Fujita, S. & Nakamura, S. (1997). Role of self-formed InGaN quantum dots for exciton localization in the purple laser diode emitting at 420 nm. Appl Phys Lett 70, 981.CrossRefGoogle Scholar
Oliver, R.A., Galtrey, M.J. & Humphreys, C.J. (2008). High resolution transmission electron microscopy and three-dimensional atom probe microscopy as complementary techniques for the high spatial resolution analysis of GaN based quantum well systems. Mater Sci Technol 24, 675–681.Google Scholar
Park, C.G., Gu, G.H., Lee, B.H. & Jang, D.H. (2013). Effects of growth pressure on the structural and optical properties of multi quantum wells (MQWs) in blue LED. Ultramicroscopy 127, 114–118.Google Scholar
Powell, R.G., Lee, N., Kim, Y. & Greene, J.E. (1993). Heteroepitaxial by reactlve-ion wurtzite and zinc-blende structure GaN grown molecular-beam epitaxy: Growth kinetics, and properties. J Appl Phys 73, 189–204.Google Scholar
Reshchikov, M.A. & Morkocç, H. (2005). Luminescence properties of defects in GaN. J Appl Phys 97, 061301.Google Scholar
Rosenauer, A., Mehrtens, T., Müller, K., Gries, K., Schowalter, M., Satyam, P.V., Bley, S., Tessarek, C., Hommel, D., Sebald, K., Seyfried, M., Gutowski, J., Avramescu, A., Engl, K. & Lutgen, S. (2011). Composition mapping in InGaN by scanning transmission electron microscopy. Ultramicroscopy 111, 1316–1327.CrossRefGoogle ScholarPubMed
Ruterana, P., Kret, S., Vivet, A., Maciejewski, G. & Dluzewski, P. (2002). Composition fluctuation in InGaN quantum wells made from molecular beam or metalorganic vapor phase epitaxial layers. J Appl Phys 91, 8979.CrossRefGoogle Scholar
Sharma, N., Thomas, P., Tricker, D. & Humphreys, C. (2000). Chemical mapping and formation of V-defects in InGaN multiple quantum wells. Appl Phys Lett 77, 1274.Google Scholar
Singh, R., Doppalapudi, D., Moustakas, T.D. & Romano, L.T. (1997). Phase separation in InGaN thick films and formation of InGaN/GaN double heterostructures in the entire alloy composition. Appl Phys Lett 70, 1089.Google Scholar
Smeeton, T.M., Kappers, M.J., Barnard, J.S., Vickers, M.E. & Humphreys, C.J. (2003). Electron-beam-induced strain within InGaN quantum wells: False indium “cluster” detection in the transmission electron microscope. Appl Phys Lett 83, 5419.CrossRefGoogle Scholar
Van der Laak, N.K., Oliver, R.A., Kappers, M.J. & Humphreys, C.J. (2007). Characterization of InGaN quantum wells with gross fluctuations in width. J Appl Phys 102, 013513.Google Scholar
Voyles, P.M., Grazul, J.L. & Muller, D.A. (2003). Imaging individual atoms inside crystals with ADF-STEM. Ultramicroscopy 96, 251–273.Google Scholar
Wu, Z.H., Fischer, A.M., Ponce, F.A., Lee, W., Ryou, J.H., Limb, J., Yoo, D. & Dupuis, R.D. (2007). Effect of internal electrostatic fields in InGaN quantum wells on the properties of green light emitting diodes. Appl Phys Lett 91, 041915.Google Scholar
Xie, J., Özgür, Ü., Fu, Y., Ni, X., Morkoç, H., Inoki, C.K., Kuan, T.S., Foreman, J.V. & Everitt, H.O. (2007). Low dislocation densities and long carrier lifetimes in GaN thin films grown on a SiNx nanonetwork. Appl Phys Lett 90, 041107.CrossRefGoogle Scholar
Xiong, X. & Moss, S.C. (1997). X-ray studies of defects and thermal vibrations in an organometallic vapor phase epitaxy grown GaN thin film. J Appl Phys 82, 2308.CrossRefGoogle Scholar
Yankovich, A.B., Kvit, A.V., Li, X., Zhang, F., Avrutin, V., Liu, H.Y., Izyumskaya, N., Özgür, Ü., Morkoç, H. & Voyles, P.M. (2012). Absence of lateral composition fluctuations in aberration-corrected STEM images of an InGaN quantum well at low dose. MRS Proceedings 1432, mrss121432g0403.CrossRefGoogle Scholar
Zhang, L., Cheng, K., Liang, H., Lieten, R., Leys, M. & Borghs, G. (2012). Photoluminescence studies of polarization effects in InGaN/(In)GaN multiple quantum well structures. Jpn J Appl Phys 51, 030207.Google Scholar
Zhao, H., Liu, G., Zhang, J., Poplawsky, J.D., Dierolf, V. & Tansu, N. (2011). Approaches for high internal quantum efficiency green InGaN light-emitting diodes with large overlap quantum wells. Opt Express 19(Suppl 4), A991–A1007.Google Scholar
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