OSA's Digital Library

Energy Express

Energy Express

  • Editor: Bernard Kippelen
  • Vol. 19, Iss. S4 — Jul. 4, 2011
  • pp: A1008–A1021

Optical polarization properties of m-plane Al x Ga1- x N epitaxial films grown on m-plane freestanding GaN substrates toward nonpolar ultraviolet LEDs

Kouji Hazu and Shigefusa F. Chichibu  »View Author Affiliations

Optics Express, Vol. 19, Issue S4, pp. A1008-A1021 (2011)

View Full Text Article

Enhanced HTML    Acrobat PDF (2014 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Light polarization characteristics of the near-band-edge optical transitions in m-plane Al x Ga1- x N epilayers suffering from anisotropic stresses are quantitatively explained. The epilayers were grown on an m-plane freestanding GaN substrate by both ammonia-source molecular beam epitaxy and metalorganic vapor phase epitaxy methods. The light polarization direction altered from Ec to E//c at the AlN mole fraction, x, between 0.25 and 0.32, where E is the electric field component of the light and ⊥ and // represent perpendicular and parallel, respectively. To give a quantitative explanation for the result, energies and oscillator strengths of the exciton transitions involving three separate valence bands are calculated as functions of strains using the Bir-Pikus Hamiltonian. The calculation predicts that the lowest energy transition (E1) is polarized to the m-axis normal to the surface (X3) for 0<x≤1, meaning that E1 emission is principally undetectable from the surface normal for any in-plane tensile strained Al x Ga1- x N. The polarization direction of observable surface emission is predicted to alter from c-axis normal (X1) to c-axis parallel (X2) for the middle energy transition (E2) and X2 to X1 for the highest energy transition (E3) between x = 0.25 and 0.32. The experimental results are consistently reproduced by the calculation.

© 2011 OSA

OCIS Codes
(160.6000) Materials : Semiconductor materials
(300.6250) Spectroscopy : Spectroscopy, condensed matter

ToC Category:
Light-Emitting Diodes

Original Manuscript: June 24, 2011
Revised Manuscript: June 29, 2011
Manuscript Accepted: June 30, 2011
Published: July 1, 2011

Virtual Issues
Optics in LEDS for Lighting (2011) Optics Express

Kouji Hazu and Shigefusa F. Chichibu, "Optical polarization properties of m-plane AlxGa1-xN epitaxial films grown on m-plane freestanding GaN substrates toward nonpolar ultraviolet LEDs," Opt. Express 19, A1008-A1021 (2011)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. Y. Taniyasu, M. Kasu, and T. Makimoto, “An aluminium nitride light-emitting diode with a wavelength of 210 nanometres,” Nature 441(7091), 325–328 (2006). [CrossRef] [PubMed]
  2. Y. Narukawa, M. Ichikawa, D. Sanga, M. Sano, and T. Mukai, “White light emitting diodes with super-high luminous efficacy,” J. Phys. D Appl. Phys. 43(35), 354002 (2010). [CrossRef]
  3. H. Tsuzuki, F. Mori, K. Takeda, M. Iwaya, S. Kamiyama, H. Amano, I. Akasaki, H. Yoshida, M. Kuwabara, Y. Yamashita, and H. Kan, “Novel UV devices on high-quality AlGaN using grooved underlying layer,” J. Cryst. Growth 311(10), 2860–2863 (2009). [CrossRef]
  4. X. Hu, J. Deng, J. P. Zhang, A. Lunev, Y. Bilenko, T. Katona, M. S. Shur, R. Gaska, M. Shatalov, and A. Khan, “Deep ultraviolet light-emitting diodes,” Phys. Stat. Solidi A 203(7), 1815–1818 (2006). [CrossRef]
  5. H. Hirayama, N. Noguchi, and N. Kamata, “222 nm Deep-Ultraviolet AlGaN Quantum Well Light-Emitting Diode with Vertical Emission Properties,” Appl. Phys. Express 3(3), 032102 (2010). [CrossRef]
  6. D. A. Miller, D. S. Chemla, T. C. Damen, A. C. Gossard, W. Wiegmann, T. H. Wood, and C. A. Burrus, “Band-Edge Electroabsorption in Quantum Well Structures: The Quantum-Confined Stark Effect,” Phys. Rev. Lett. 53(22), 2173–2176 (1984). [CrossRef]
  7. P. Waltereit, O. Brandt, A. Trampert, H. T. Grahn, J. Menniger, M. Ramsteiner, M. Reiche, and K. H. Ploog, “Nitride semiconductors free of electrostatic fields for efficient white light-emitting diodes,” Nature 406(6798), 865–868 (2000). [CrossRef] [PubMed]
  8. M. D. Craven, P. Waltereit, J. S. Speck, and S. P. DenBaars, “Well-width dependence of photoluminescence emission from a-plane GaN/AlGaN multiple quantum wells,” Appl. Phys. Lett. 84(4), 496–498 (2004). [CrossRef]
  9. T. Koida, S. F. Chichibu, T. Sota, M. D. Craven, D. A. Haskell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Improved quantum efficiency in nonpolar (110) AlGaN/GaN quantum wells grown on GaN prepared by lateral epitaxial overgrowth,” Appl. Phys. Lett. 84(19), 3768–3770 (2004). [CrossRef]
  10. J. S. Speck and S. F. Chichibu, “Nonpolar and Semipolar Group III Nitride-Based Materials,” MRS Bull. 34(05), 304–312 (2009). [CrossRef]
  11. H. Masui, T. J. Baker, M. Iza, H. Zhong, S. Nakamura, and S. P. DenBaars, “Light-polarization characteristics of electroluminescence from InGaN/GaN light-emitting diodes prepared on (112)-plane GaN,” J. Appl. Phys. 100(11), 113109 (2006). [CrossRef]
  12. M. Masui, T. J. Baker, R. Sharma, P. M. Pattison, M. Iza, H. Zhong, S. Nakamura, and S. P. DenBaars, “First-Moment Analysis of Polarized Light Emission from InGaN/GaN Light-Emitting Diodes Prepared on Semipolar Planes,” Jpn. J. Appl. Phys. 45(34), L904–L906 (2006). [CrossRef]
  13. R. Sharma, P. M. Pattison, H. Masui, R. M. Farrell, T. J. Baker, B. A. Haskell, F. Wu, S. P. DenBaars, J. S. Speck, and S. Nakamura, “Demonstration of a semipolar (10) InGaN/GaN green light emitting diode,” Appl. Phys. Lett. 87(23), 231110 (2005). [CrossRef]
  14. K. Okamoto, H. Ohta, D. Nakagawa, M. Sonobe, J. Ichihara, and H. Takasu, “Dislocation-Free m-Plane InGaN/GaN Light-Emitting Diodes on m-Plane GaN Single Crystals,” Jpn. J. Appl. Phys. 45(45), L1197–L1199 (2006). [CrossRef]
  15. M. C. Schmidt, K.-C. Kim, H. Sato, N. Fellows, H. Masui, S. Nakamura, S. P. DenBaars, and J. S. Speck, “High Power and High External Efficiency m-Plane InGaN Light Emitting Diodes,” Jpn. J. Appl. Phys. 46(7), L126–L128 (2007). [CrossRef]
  16. K. Fujito, K. Kiyomi, T. Mochizuki, H. Oota, H. Namita, S. Nagao, and I. Fujimura, “High-quality nonpolar m-plane GaN substrates grown by HVPE,” Phys. Stat. Solidi A 205(5), 1056–1059 (2008). [CrossRef]
  17. K. Iso, H. Yamada, H. Hirasawa, N. Fellows, M. Saito, K. Fujito, S. P. DenBaars, J. S. Speck, and S. Nakamura, “High Brightness InGaN/GaN Light Emitting Diode on Nonpolar m-plane Bulk GaN Substrate,” Jpn. J. Appl. Phys. 46(40), L960–L962 (2007). [CrossRef]
  18. S. F. Chichibu, A. Uedono, T. Onuma, S. P. DenBaars, U. K. Mishra, J. S. Speck, and S. Nakamura, “Impact of Point Defects on the Luminescence Properties of (Al,Ga)N,” Mater. Sci. Forum 590, 233–248 (2008). [CrossRef]
  19. T. Onuma, K. Hazu, A. Uedono, T. Sota, and S. F. Chichibu, “Identification of extremely radiative nature of AlN by time-resolved photoluminescence,” Appl. Phys. Lett. 96(6), 061906 (2010). [CrossRef]
  20. S. F. Chichibu, T. Onuma, K. Hazu, and A. Uedono, “Major impacts of point defects and impurities on the carrier recombination dynamics in AlN,” Appl. Phys. Lett. 97(20), 201904 (2010). [CrossRef]
  21. K. Domen, K. Kondo, A. Kuramata, and T. Tanahasi, “Gain analysis for surface emission by optical pumping of wurtzite GaN,” Appl. Phys. Lett. 69(1), 94–96 (1996). [CrossRef]
  22. T. Ohtoshi, A. Niwa, and T. Kuroda, “Dependence of optical gain on crystal orientation in wurtzite-GaN strained quantum-well lasers,” J. Appl. Phys. 82(4), 1518–1520 (1997). [CrossRef]
  23. B. Gil and A. Alemu, “Optical anisotropy of excitons in strained GaN epilayers grown along the <100> direction,” Phys. Rev. B 56(19), 12446–12453 (1997). [CrossRef]
  24. A. Alemu, B. Gil, M. Julier, and S. Nakamura, “Optical properties of wurtzite GaN epilayers grown on A-plane sapphire,” Phys. Rev. B 57(7), 3761–3764 (1998). [CrossRef]
  25. S.-H. Park and S.-L. Chuang, “Crystal-orientation effects on the piezoelectric field and electronic properties of strained wurtzite semiconductors,” Phys. Rev. B 59(7), 4725–4737 (1999). [CrossRef]
  26. S. Ghosh, P. Waltereit, O. Brandt, H. T. Grahn, and K. H. Ploog, “Electronic band structure of wurtzite GaN under biaxial strain in the M plane investigated with photoreflectance spectroscopy,” Phys. Rev. B 65(7), 075202 (2002). [CrossRef]
  27. L. R. Ram-Mohan, A. M. Girgis, J. D. Albrecht, and C. W. Litton, “Wavefunction engineering of layered wurtzite semiconductors grown along arbitrary crystallographic directions,” Superlattices Microstruct. 39(6), 455–477 (2006). [CrossRef]
  28. S. –H. Park and D. Ahn, “Depolarization effects in (112)-oriented InGaN/GaN quantum well structures,” Appl. Phys. Lett. 90, 013505 1–3 (2007). [CrossRef]
  29. A. A. Yamaguchi, “Anisotropic Optical Matrix Elements in Strained GaN Quantum Wells on Semipolar and Nonpolar Substrates,” Jpn. J. Appl. Phys. 46(33), L789–L791 (2007). [CrossRef]
  30. A. A. Yamaguchi, “Anisotropic optical matrix elements in strained GaN-quantum wells with various substrate orientations,” Phys. Stat. Solidi C 5(6), 2329–2332 (2008). [CrossRef]
  31. J. Bhattacharyya, S. Ghosh, and H. T. Grahn, “Optical polarization properties of interband transitions in strained group-III-nitride alloy films on GaN substrates with nonpolar orientation,” Appl. Phys. Lett. 93(5), 051913 (2008). [CrossRef]
  32. G. L. Bir and G. E. Pikus, Symmetry and Strain-Induced Effect in Semiconductors, (Wiley, New York, 1974).
  33. T. Hoshi, K. Hazu, K. Ohshita, M. Kagaya, T. Onuma, K. Fujito, H. Namita, and S. F. Chichibu, “Impacts of anisotropic lattice relaxation on crystal mosaicity and luminescence spectra of m-plane AlxGa1-xN films grown on m-plane freestanding GaN substrates by NH3 source molecular beam epitaxy,” Appl. Phys. Lett. 94(7), 071910 (2009). [CrossRef]
  34. S. F. Chichibu, H. Yamaguchi, L. Zhao, M. Kubota, K. Okamoto, and H. Ohta, “Optical properties of nearly stacking-fault-free m-plane GaN homoepitaxial films grown by metal organic vapor phase epitaxy on low defect density freestanding GaN substrates,” Appl. Phys. Lett. 93(12), 129901 (2008) (erratum). [CrossRef]
  35. R. People and J. C. Bean, “Calculation of critical layer thickness versus lattice mismatch for GexSi1-x/Si strained-layer heterostructures,” Appl. Phys. Lett. 47(3), 322–324 (1985). [CrossRef]
  36. T. Onuma, T. Koyama, A. Chakraborty, M. McLaurin, B. A. Haskell, P. T. Fini, S. Keller, S. P. DenBaars, J. S. Speck, S. Nakamura, U. K. Mishra, T. Sota, and S. F. Chichibu, “Radiative and nonradiative lifetimes in nonpolar m-plane InxGa1-xN/GaN multiple quantum wells grown on GaN templates prepared by lateral epitaxial overgrowth,” J. Vac. Sci. Technol. B 25(4), 1524–1528 (2007). [CrossRef]
  37. E. C. Young, C. S. Gallinat, F. Wu, and J. S. Speck, “Ammonia molecular beam epitaxy of m-plane GaN and InGaN for long wavelength optoelectronics,” presented at International Workshop on Nitride Semiconductors (IWN), Montreux, Switzerland, 6–10, Oct. 2008.
  38. S. F. Chichibu, H. Yamaguchi, L. Zhao, M. Kubota, T. Onuma, and H. Ohta, “Improved characteristics and issues of m-plane freestanding GaN substrates by metalorganic vapor phase epitaxy,” Appl. Phys. Lett. 93(15), 151908 (2008). [CrossRef]
  39. A. Shikanai, T. Azuhata, T. Sota, S. Chichibu, A. Kuramata, K. Horino, and S. Nakamura, “Biaxial strain dependence of exciton resonance energies in wurtzite GaN,” J. Appl. Phys. 81(1), 417–424 (1997). [CrossRef]
  40. T. Onuma, T. Shibata, K. Kosaka, K. Asai, S. Sumiya, M. Tanaka, T. Sota, A. Uedono, and S. F. Chichibu, “Free and bound exciton fine structures in AlN epilayers grown by low-pressure metalorganic vapor phase epitaxy,” J. Appl. Phys. 105(2), 023529 (2009). [CrossRef]
  41. T. Onuma, S. F. Chichibu, A. Uedono, T. Sota, P. Cantu, T. M. Katona, J. F. Keading, S. Keller, U. K. Mishra, S. Nakamura, and S. P. DenBaars, “Radiative and nonradiative processes in strain-free AlxGa1-xN films studied by time-resolved photoluminescence and positron annihilation techniques,” J. Appl. Phys. 95(5), 2495–2504 (2004). [CrossRef]
  42. B. Monemar, “Fundamental energy gap of GaN from photoluminescence excitation spectra,” Phys. Rev. B 10(2), 676–681 (1974). [CrossRef]
  43. H. Ikeda, T. Okamura, K. Matsukawa, T. Sota, M. Sugawara, T. Hoshi, P. Cantu, R. Sharma, J. F. Kaeding, S. Keller, U. K. Mishra, K. Kosaka, K. Asai, S. Sumiya, T. Shibata, M. Tanaka, J. S. Speck, S. P. DenBaars, S. Nakamura, T. Onuma, and S. F. Chichibu, ““Impact of strain on free-exciton resonance energies in wurtzite AlN,” J. Appl. Phys. 103(8), 089901 (2008) (erratum). [CrossRef]
  44. H. G. Grimmeiss and B. Monemar, “Low-Temperature Luminescence of GaN,” J. Appl. Phys. 41(10), 4054–4058 (1970). [CrossRef]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article

OSA is a member of CrossRef.

CrossCheck Deposited