Abstract
Self-assembled GaN nanorods were grown by metal-organic chemical vapor deposition. A highly regular rosette-shaped cathodoluminescence pattern in the GaN nanorods is observed, where its origin is helpful to deepen the understanding of GaN nanorod growth. The pattern forms at the very early stages of nanorod growth, which consists of yellow luminescence at the edges and the non-luminous region at six vertices of the hexagon. To clarify its origin, we carried out detailed cathodoluminescence studies, electron microscopy studies and nanoscale secondary ion mass spectrometry at both the nanorod surface and cross-section. We found the pattern is not related to optical resonance modes or polarity inversion, which are commonly reported in GaN nanostructures. After chemical composition and strain analysis, we found higher carbon and nitrogen cluster concentration and large compressive strain at the pattern area. The pattern formation may relate to facet preferential distribution of non-radiative recombination centers related to excess carbon/nitrogen. This work provides an insight into strain distribution and defect-related emission in GaN nanorod, which is critical for future optoelectronic applications.
Similar content being viewed by others
References
Ebaid, M.; Kang, J. H.; Lim, S. H.; Ha, J. S.; Lee, J. K.; Cho, Y. H.; Ryu, S. W. Enhanced solar hydrogen generation of high density, high aspect ratio, coaxial InGaN/GaN multi-quantum well nanowires. Nano Energy2015, 12, 215–223.
Golam Sarwar, A. T. M.; Myers, R. C. Exploiting piezoelectric charge for high performance graded InGaN nanowire solar cells. Appl. Phys. Lett.2012, 101, 143905.
Howell, S. L.; Padalkar, S.; Yoon, K.; Li, Q. M.; Koleske, D. D.; Wierer, J. J.; Wang, G. T.; Lauhon, L. J. Spatial mapping of efficiency of GaN/InGaN nanowire array solar cells using scanning photocurrent microscopy. Nano Lett.2013, 13, 5123–5128.
Li, C. Y.; Wright, J. B.; Liu, S.; Lu, P.; Figiel, J. J.; Leung, B.; Chow, W. W.; Brener, I.; Koleske, D. D.; Luk, T. S. et al. Nonpolar InGaN/GaN core-shell single nanowire lasers. Nano Lett.2017, 17, 1049–1055.
Zhao, C.; Ng, T. K.; ElAfandy, R. T.; Prabaswara, A.; Consiglio, G B.; Ajia, I. A.; Roqan, I. S.; Janjua, B.; Shen, C.; Eid, J. et al. Droop-free, reliable, and high-power InGaN/GaN nanowire light-emitting diodes for monolithic metal-optoelectronics. Nano Lett.2016, 16, 4616–4623.
Dai, X.; Messanvi, A.; Zhang, H. Z.; Durand, C.; Eymery, J.; Bougerol, C.; Julien, F. H.; Tchernycheva, M. Flexible light-emitting diodes based on vertical nitride nanowires. Nano Lett.2015, 15, 6958–6964.
Riley, J. R.; Padalkar, S.; Li, Q. M.; Lu, P.; Koleske, D. D.; Wierer, J. J.; Wang, G. T.; Lauhon, L. J. Three-dimensional mapping of quantum wells in a GaN/InGaN core-shell nanowire light-emitting diode array. Nano Lett.2013, 13, 4317–4325.
Neugebauer, J.; Van de Walle, C. G. Gallium vacancies and the yellow luminescence in GaN. Appl. Phys. Lett.1996, 69, 503–505.
Ogino, T.; Aoki, T. Mechanism of yellow luminescence in GaN. Jpn. J. Appl. Phys.1980, 19, 2395–2405.
Ponce, F. A.; Bour, D. P.; Götz, W.; Wright, P. J. Spatial distribution of the luminescence in GaN thin films. Appl. Phys. Lett.1996, 68, 57–59.
Schubert, E. F. Radiative and non-radiative recombination. In Light-Emitting Diodes. Schubert, E. F., Ed.; Cambridge University Press: Cambridge, 2006; pp 35–44.
Pankove, J. I.; Hutchby, J. A. Photoluminescence of ion-implanted GaN. J. Appl. Phys.1976, 47, 5387–5390.
Liao, H.; Li, J. C.; Wei, T. T.; Wen, P. J.; Li, M.; Hu, X. D. First-principles study of CN point defects on sidewall surface of [0001]-oriented GaN nanowires. Appl. Surf. Sci.2019, 467–468, 293–297.
Kucheyev, S. O.; Toth, M.; Phillips, M. R.; Williams, J. S.; Jagadish, C.; Li, G. Chemical origin of the yellow luminescence in GaN. J. Appl. Phys.2002, 91, 5867–5874.
Li, X.; Bohn, P. W.; Coleman, J. J. Impurity states are the origin of yellow-band emission in GaN structures produced by epitaxial lateral overgrowth. Appl. Phys. Lett.1999, 75, 4049–4051.
Christenson, S. G.; Xie, W. Y.; Sun, Y. Y.; Zhang, S. B. Carbon as a source for yellow luminescence in GaN: Isolated CN defect or its complexes. J. Appl. Phys.2015, 118, 135708.
Reshchikov, M. A.; Demchenko, D. O.; Usikov, A.; Helava, H.; Makarov, Y. Carbon defects as sources of the green and yellow luminescence bands in undoped GaN. Phys. Rev. B2014, 90, 235203.
Lyons, J. L.; Janotti, A.; Van de Walle, C. G. Carbon impurities and the yellow luminescence in GaN. Appl. Phys. Lett.2010, 97, 152108.
Armitage, R.; Hong, W.; Yang, Q.; Feick, H.; Gebauer, J.; Weber, E. R.; Hautakangas, S.; Saarinen, K. Contributions from gallium vacancies and carbon-related defects to the “yellow luminescence” in GaN. Appl. Phys. Lett.2003, 82, 3457–3459.
Demchenko, D. O.; Diallo, I. C.; Reshchikov, M. A. Yellow luminescence of gallium nitride generated by carbon defect complexes. Phys. Rev. Lett.2013, 110, 087404.
Götz, W.; Johnson, N. M.; Chen, C.; Liu, H.; Kuo, C.; Imler, W. Activation energies of Si donors in GaN. Appl. Phys. Lett.1996, 68, 3144–3146.
Soh, C. B.; Chua, S. J.; Lim, H. F.; Chi, D. Z.; Tripathy, S.; Liu, W. Assignment of deep levels causing yellow luminescence in GaN. J. Appl. Phys.2004, 96, 1341–1347.
Kaufmann, U.; Kunzer, M.; Obloh, H.; Maier, M.; Manz, C.; Ramakrishnan, A.; Santic, B. Origin of defect-related photoluminescence bands in doped and nominally undoped GaN. Phys. Rev. B1999, 59, 5561–5567.
Mattila, T.; Nieminen, R. M. Point-defect complexes and broadband luminescence in GaN and AlN. Phys. Rev. B1997, 55, 9571–9576.
Toth, M.; Fleischer, K.; Phillips, M. R. Direct experimental evidence for the role of oxygen in the luminescent properties of GaN. Phys. Rev. B1999, 59, 1575–1578.
Slack, G. A.; Schowalter, L. J.; Morelli, D.; Freitas Jr, J. A. Some effects of oxygen impurities on AlN and GaN. J. Cryst. Growth2002, 246, 287–298.
Liu, B. D.; Yuan, F.; Dierre, B.; Sekiguchi, T.; Zhang, S.; Xu, Y. K.; Jiang, X. Origin of yellow-band emission in epitaxially grown GaN nanowire arrays. ACS Appl. Mater. Interfaces2014, 6, 14159–14166.
Coulon, P. M.; Alloing, B.; Brändli, V.; Vennéguès, P.; Leroux, M.; Zúñiga-Pérez, J. Dislocation filtering and polarity in the selective area growth of GaN nanowires by continuous-flow metal organic vapor phase epitaxy. Appl. Phys. Express2016, 9, 015502.
Colby, R.; Liang, Z. W.; Wildeson, I. H, Ewoldt, D. A.; Sands, T. D.; García, R. E.; Stach, E. A. Dislocation filtering in GaN nanostructures. Nano Lett.2010, 10, 1568–1573.
Zhao, C.; Ng, T. K.; Prabaswara, A.; Conroy, M.; Jahangir, S.; Frost, T.; O’Connell, J.; Holmes, J. D.; Parbrook, P. J.; Bhattacharya, P. et al. An enhanced surface passivation effect in InGaN/GaN disk-in-nanowire light emitting diodes for mitigating Shockley-Read-Hall recombination. Nanoscale2015, 7, 16658–16665.
Li, Q. M.; Wang, G. T. Spatial distribution of defect luminescence in GaN nanowires. Nano Lett.2010, 10, 1554–1558.
Huang, P.; Zong, H.; Shi, J. J.; Zhang, M.; Jiang, X. H.; Zhong, H. X.; Ding, Y. M.; He, Y. P.; Lu, J.; Hu, X. D. Origin of 3.45 eV emission line and yellow luminescence band in GaN nanowires: Surface microwire and defect. ACS Nano2015, 9, 9276–9283.
Zhao, B.; Lockrey, M. N.; Caroff, P.; Wang, N.; Li, L.; Wong-Leung, J.; Tan, H. H.; Jagadish, C. The effect of nitridation on the polarity and optical properties of GaN self-assembled nanorods. Nanoscale2018, 10, 11205–11210.
de la Mata, M.; Magen, C.; Gazquez, J.; Utama, M. I. B.; Heiss, M.; Lopatin, S.; Furtmayr, F.; Fernández-Rojas, C. J.; Peng, B.; Morante, J. R. et al. Polarity assignment in ZnTe, GaAs, ZnO, and GaN-AlN nanowires from direct dumbbell analysis. Nano Lett.2012, 12, 2579–2586.
Wang, N. W.; Chen, X. D.; Yang, Y. H.; Dong, J. W.; Wang, C. X.; Yang, G. W. Diffuse reflection inside a hexagonal nanocavity. Sci. Rep. 2013, 3, 1298.
Tamboli, A. C.; Schmidt, M. C.; Hirai, A.; DenBaars, S. P.; Hu, E. L. Observation of whispering gallery modes in nonpolar m-plane GaN microdisks. Appl. Phys. Lett.2009, 94, 251116.
Kouno, T.; Kishino, K.; Sakai, M. Lasing action on whispering gallery mode of self-organized GaN hexagonal microdisk crystal fabricated by RF-plasma-assisted molecular beam epitaxy. IEEE J. Quantum Elect.2011, 47, 1565–1570.
Tessarek, C.; Dieker, C.; Spiecker, E.; Christiansen, S. Growth of GaN nanorods and wires and spectral tuning of whispering gallery modes in tapered GaN wires. Jpn. J. Appl. Phys.2013, 52, 08JE09.
Tessarek, C.; Goldhahn, R.; Sarau, G.; Heilmann, M.; Christiansen, S. Carrier-induced refractive index change observed by a whispering gallery mode shift in GaN microrods. New J. Phys.2015, 17, 083047.
Baek, H.; Hyun, J. K.; Chung, K.; Oh, H.; Yi, G. C. Selective excitation of Fabry-Pérot or whispering-gallery mode-type lasing in GaN microrods. Appl. Phys. Lett.2014, 105, 201108.
Coulon, P. M.; Hugues, M.; Alloing, B.; Beraudo, E.; Leroux, M.; Zuniga-Perez, J. GaN microwires as optical microcavities: Whispering gallery modes vs. Fabry-Pérot modes. Opt. Express2012, 20, 18707–18716.
Coulon, P. M.; Mexis, M.; Teisseire, M.; Jublot, M.; Vennéguès, P.; Leroux, M.; Zuniga-Perez, J. Dual-polarity GaN micropillars grown by metalorganic vapour phase epitaxy: Cross-correlation between structural and optical properties. J. Appl. Phys.2014, 115, 153504.
Volotsenko, I.; Molotskii, M.; Barkay, Z.; Marczewski, J.; Grabiec, P.; Jaroszewicz, B.; Meshulam, G.; Grunbaum, E.; Rosenwaks, Y. Secondary electron doping contrast: Theory based on scanning electron microscope and Kelvin probe force microscopy measurements. J. Appl. Phys.2010, 107, 014510.
Seiler, H. Secondary electron emission in the scanning electron microscope. J. Appl. Phys.1983, 54, R1–R18.
Sealy, C. P.; Castell, M. R.; Wilshaw, P. R. Mechanism for secondary electron dopant contrast in the SEM. J. Electron Microsc.2000, 49, 311–321.
Ko, S. M.; Kim, J. H.; Ko, Y. H.; Chang, Y. H.; Kim, Y. H.; Yoon, J.; Lee, J. Y.; Cho, Y. H. Growth mechanism of catalyst-free and mask-free heteroepitaxial GaN submicrometer- and micrometer-sized rods under biaxial strain: Variation of surface energy and adatom kinetics. Cryst. Growth Des.2012, 12, 3838–3844.
Bae, S. Y.; Lee, J. Y.; Min, J. H.; Lee, D. S. Morphology evolution of pulsed-flux Ga-polar GaN nanorod growth by metal organic vapor phase epitaxy and its nucleation dependence. Appl. Phys. Express2013, 6, 075501.
Yuan, X. M.; Yang, J. B.; He, J.; Tan, H. H.; Jagadish, C. Role of surface energy in nanowire growth. J. Phys. D: Appl. Phys.2018, 51, 283002.
Thillosen, N.; Sebald, K.; Hardtdegen, H.; Meijers, R.; Calarco, R.; Montanari, S.; Kaluza, N.; Gutowski, J.; Lüth, H. The state of strain in single GaN nanocolumns as derived from micro-photoluminescence measurements. Nano Lett.2006, 6, 704–708.
Hytch, M. J.; Snoeck, E.; Kilaas, R. Quantitative measurement of displacement and strain fields from HREM micrographs. Ultramicroscopy1998, 74, 131–146.
Lyons, J. L.; Janotti, A.; Van de Walle, C. G. Effects of carbon on the electrical and optical properties of InN, GaN, and AlN. Phys. Rev. B2014, 89, 035204.
Wright, A. F. Substitutional and interstitial carbon in wurtzite GaN. J. Appl. Phys.2002, 92, 2575–2585.
Paskov, P. P.; Monemar, B. 2-point defects in group-III nitrides. In Defects in Advanced Electronic Materials and Novel Low Dimensional Structures. Stehr, J.; Buyanova, I.; Chen, W., Eds.; Woodhead Publishing: Duxford, 2018; pp 27–61.
Takakuwa-Hongo, C.; Tomita, M. High-sensitivity SIMS analysis of carbon in gan films by molecular ion detection. Surf. Interface Anal.1997, 25, 966–969.
Qian, F.; Brewster, M.; Lim, S. K.; Ling, Y. C.; Greene, C.; Laboutin, O.; Johnson, J. W.; Gradečak, S.; Cao, Y.; Li, Y. Controlled synthesis of AlN/GaN multiple quantum well nanowire structures and their optical properties. Nano Lett.2012, 12, 3344–3350.
Lim, S. K.; Brewster, M.; Qian, F.; Li, Y.; Lieber, C. M.; Gradečak, S. Direct correlation between structural and optical properties of III–V nitride nanowire heterostructures with nanoscale resolution. Nano Lett.2009, 9, 3940–3944.
Zheng, C. L.; Wong-Leung, J.; Gao, Q.; Tan, H. H.; Jagadish, C.; Etheridge, J. Polarity-driven 3-fold symmetry of GaAs/AlGaAs core multishell nanowires. Nano Lett.2013, 13, 3742–3748.
Acknowledgements
The Australian Research Council is acknowledged for its financial support. Access to the facilities is made possible through the Australian National Fabrication Facility, Australian Capital Territory Node. The authors also acknowledge the assistance of Dr Gilberto Casillas Garcia at the Electron Microscopy Centre at the University of Wollongong and Paul Guagliardo at Centre for Microscopy, Characterisation and Analysis at the University of Western Australia. B. J. Z. would like to thank for Dr Xiangyuan Cui at the University of Sydney for helpful discussion on the GaN related defects. B. J. Z. would like to thank the China Scholarship Council and the Australia National University for her scholarship support. X. Y. thanks the National Natural Science Foundation of China (Nos. 61974166 and 51702368) for financial support.
Author information
Authors and Affiliations
Corresponding authors
Electronic Supplementary Material
Rights and permissions
About this article
Cite this article
Zhao, B., Lockrey, M.N., Wang, N. et al. Highly regular rosette-shaped cathodoluminescence in GaN self-assembled nanodisks and nanorods. Nano Res. 13, 2500–2505 (2020). https://doi.org/10.1007/s12274-020-2886-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12274-020-2886-6