Abstract
Bulk AlN crystals grown by sublimation on SiC substrates exhibit relatively high dislocation densities. The kind of defect formation at early growth stages influences the structural quality of the grown crystals. In this work, the dislocation distribution near to the interface is understood through investigation of thin (≤1.5 mm) continuous (non-cracked) freestanding crystals obtained in one process with the evaporation of the substrates. The AlN specimens were characterized using synchrotron radiation imaging techniques. We revealed by triple-axis X-ray diffraction study that, near to the former interface, randomly distributed dislocations configured to form boundaries between \(\sim \)0.02\(^{\circ }\) misoriented sub-grains (from [0001] direction). Threading dislocation structure similar to that in epitaxial GaN films was not detected. To explain these observations, a theoretical model of misfit stress relaxation near the interface is suggested.
Similar content being viewed by others
References
Seong T-Y, Han J, Amano H, Morko H (eds) (2013) III-Nitride based light emitting diodes and applications. Springer, Berlin. doi:10.1007/978-94-007-5863-6
Hartmann C, Wollweber J, Sintonen S, Dittmar A, Kirste L, Kollowa S, Irmscher K, Bickermann M (2016) Preparation of deep UV transparent AlN substrates with high structural perfection for optoelectronic devices. CrystEngComm 18:3488–3497. doi:10.1039/c6ce00622a
Sumathi RR, Gille P (2014) Role of SiC substrate polarity on the growth and properties of bulk AlN single crystals. J Mater Sci 25:3733–3741. doi:10.1007/s10854-014-2083-z
Nagai I, Kato T, Miura T, Kamata H, Naoe K, Sanada K, Okumura H (2010) AlN bulk single crystal growth on 6H–SiC substrates by sublimation method. J Cryst Growth 312:2699–2704. doi:10.1016/j.jcrysgro.2010.05.044
Sumathi RR (2013) Bulk AlN single crystal growth on foreign substrate and preparation of free-standing native seeds. CrystEngComm 15:2232–2240. doi:10.1039/c2ce26599k
Sumathi RR, Barz RU, Straubinger T, Gille P (2012) Structural and surface topography analysis of AlN single crystals grown on 6H-SiC substrates. J Cryst Growth 360:193–196. doi:10.1016/j.jcrysgro.2011.11.054
Kapolnek D, Wu XH, Heying B, Keller S, Keller BP, Mishra UK, DenBaars SP, Speck JS (1995) Structural evolution in epitaxial metalorganic chemical vapor deposition grown GaN films on sapphire. Appl Phys Lett 67:1541–1543. doi:10.1063/1.114486
Heying B, Wu XH, Keller S, DenBaars SP, Speck JS (1996) Role of threading dislocation structure on the X-ray diffraction peak widths in epitaxial GaN films. Appl Phys Lett 68:643–645. doi:10.1063/1.116495
Kyutt RN, Ratnikov VV, Mosina GN, Shcheglov MP (1999) Structural perfection of GaN epitaxial layers according to X-ray diffraction measurements. Phys Solid State 41:25–31. doi:10.1134/1.1130722
Lee CD, Ramachandran V, Sagar A, Feenstra RM, Greve DW, Sarney WL, Salamanca-Riba L, Look DC, Bai S, Choyke WJ, Devaty RP (2001) Properties of GaN epitaxial layers grown on 6H–SiC (0001) by plasma-assisted molecular beam epitaxy. J Electron Mater 30:162–169. doi:10.1007/s11664-001-0010-6
Argunova TS, Gutkin MY, Mokhov EN, Kazarova OP, Lim J-H, Scheglov MP (2015) Prevention of AlN crystal from cracking on SiC substrates by evaporation of the substrates. Phys Solid State 57:2473–2478. doi:10.1134/S1063783415120057
Argunova TS, Gutkin MY, Kazarova OP, Mokhov EN, Nagalyuk SS, Je JH (2015) Synchrotron X-ray study on crack prevention in AlN crystals grown on gradually decomposing SiC substrates. Mater Sci Forum 821–823:1011–1014. doi:10.4028/www.scientific.net/MSF.821-823.1011
Mokhov E, Izmaylova I, Kazarova O, Wolfson A, Nagalyuk S, Litvin D, Vasiliev A, Helava H, Makarov Y (2013) Specific features of sublimation growth of bulk AlN crystals on SiC wafers. Phys Status Solidi C 10:445–448. doi:10.1002/pssc.201200638
Balzar D (1999) In: Snyder RL, Fiala J, Bunge HJ (eds) Defect and microstructure analysis by diffraction. Oxford University Press, New York, pp 94–126
Floro JA, Follstaedt DM, Provencio P, Hearne SJ, Lee SR (2004) Misfit dislocation formation in the AlGaN/GaN heterointerface. J Appl Phys 96:7087–7094. doi:10.1063/1.1812361
Miyanaga M, Mizuhara N, Fujiwara S, Shimazu M, Nakahata H, Kawase T (2007) Evaluation of AlN single-crystal grown by sublimation method. J Cryst Growth 300:45–49. doi:10.1016/j.jcrysgro.2006.10.233
Bickermann M, Epelbaum BM, Filip O, Heimann P, Nagata S, Winnacker A (2008) Structural properties of aluminum nitride bulk single crystals grown by PVT. Phys Status Solidi C 5:1502–1504. doi:10.1002/pssc.200778422
Kamata H, Naoe K, Sanada K, Ichinose N (2009) Single-crystal growth of aluminum nitride on 6H–SiC substrates by an open-system sublimation method. J Cryst Growth 311:1291–1295. doi:10.1016/j.jcrysgro.2008.12.025
Acknowledgements
Synchrotron X-ray experiments were supported by the Ministry of Trade, Industry and Energy (MOTIE) and Korea Institute for Advancement of Technology (KIAT) through the International Cooperative R&D Program. M. Yu. Gutkin acknowledges the support of the Russian Science Foundation (Grant RSF No. 14-29-00086) in development of the theoretical model of misfit stress relaxation. E. N. Mokhov acknowledges the support of the Russian Science Foundation (Grant RSF No. 16–42–01098) for providing the sublimation growth of AlN layers on evaporating SiC substrates.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Argunova, T.S., Gutkin, M.Y., Shcherbachev, K.D. et al. Microstructure and strength of AlN–SiC interface studied by synchrotron X-rays. J Mater Sci 52, 4244–4252 (2017). https://doi.org/10.1007/s10853-016-0679-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10853-016-0679-9