Origin of defect-insensitive emission probability in In-containing (Al,In,Ga)N alloy semiconductors

Abstract

Group-III-nitride semiconductors have shown enormous potential as light sources for full-colour displays, optical storage and solid-state lighting. Remarkably, InGaN blue- and green-light-emitting diodes (LEDs) emit brilliant light although the threading dislocation density generated due to lattice mismatch is six orders of magnitude higher than that in conventional LEDs. Here we explain why In-containing (Al,In,Ga)N bulk films exhibit a defect-insensitive emission probability. From the extremely short positron diffusion lengths (<4 nm) and short radiative lifetimes of excitonic emissions, we conclude that localizing valence states associated with atomic condensates of In–N preferentially capture holes, which have a positive charge similar to positrons. The holes form localized excitons to emit the light, although some of the excitons recombine at non-radiative centres. The enterprising use of atomically inhomogeneous crystals is proposed for future innovation in light emitters even when using defective crystals.

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Figure 1: Schematic representation for polarizations and energy band profiles of strained In0.15Ga0.85N/GaN quantum wells.
Figure 2: Internal quantum efficiency ηint of the near-band-edge emission peaks in In-containing 3D (Al,In,Ga)N films.
Figure 3: Radiative and non-radiative lifetimes for the NBE emission in In-containing 3D (Al,In,Ga)N films.
Figure 4: Panchromatic CL mapping image and intensity line profile for the NBE CL peak in a-plane In0.1Ga0.9N/GaN MQW.
Figure 5: Schematic representations of trapped positrons in In-containing 3D (Al,In,Ga)N films.
Figure 6: Relations between effective non-radiative lifetime τNR,eff for the near-band-edge PL peak at 300 K and point defects in In-containing 3D (Al,In,Ga)N films.

References

  1. 1

    Nakamura, S. & Fasol, G. The Blue Laser Diode (Springer, Berlin, 1997).

    Google Scholar 

  2. 2

    Akasaki, I. & Amano, H. Crystal growth and conductivity control of group III nitride semiconductors and their application to short wavelength light emitters. Jpn J. Appl. Phys. 1 36, 5393–5408 (1997).

    Article  Google Scholar 

  3. 3

    Ponce, F. A. & Bour, D. Nitride-based semiconductors for blue and green light-emitting devices. Nature 386, 351–359 (1997).

    Article  Google Scholar 

  4. 4

    Chichibu, S. F. et al. Limiting factors of room-temperature nonradiative photoluminescence lifetime in polar and nonpolar GaN studied by time-resolved photoluminescence and slow positron annihilation techniques. Appl. Phys. Lett. 86, 021914 (2005).

    Article  Google Scholar 

  5. 5

    Miller, D. A. et al. Band-edge electroabsorption in quantum well structures: The quantum-confined Stark effect. Phys. Rev. Lett. 53, 2173–2176 (1984).

    Article  Google Scholar 

  6. 6

    Chichibu, S., Azuhata, T., Sota, T. & Nakamura, S. Spontaneous emission of localized excitons in InGaN single and multiquantum well structures. Appl. Phys. Lett. 69, 4188–4190 (1996).

    Article  Google Scholar 

  7. 7

    Takeuchi, T. et al. Quantum-confined Stark effect due to piezoelectric fields in GaInN strained quantum wells. Jpn J. Appl. Phys. 2 36, L382–L385 (1997).

    Article  Google Scholar 

  8. 8

    Bernardini, F. & Fiorentini, V. Macroscopic polarization and band offsets at nitride heterojunctions. Phys. Rev. B 57, R9427–R9430 (1998).

    Article  Google Scholar 

  9. 9

    Chichibu, S. F. et al. Optical properties of InGaN quantum wells. Mater. Sci. Eng. B 59, 298–306 (1999).

    Article  Google Scholar 

  10. 10

    Hangleiter, A., Im, J. S., Off, J. & Scholz, F. Optical properties of nitride quantum wells: How to separate fluctuations and polarization field effects. Phys. Status Solidi B 216, 427–430 (1999).

    Article  Google Scholar 

  11. 11

    Chichibu, S. F. et al. Impact of internal electric field and localization effect on quantum well excitons in AlGaN/GaN/InGaN light emitting diodes. Phys. Status Solidi A 183, 91–98 (2001).

    Article  Google Scholar 

  12. 12

    Narukawa, Y., Kawakami, Y., Fujita, Sg. & Nakamura, S. Dimensionality of excitons in laser-diode structures composed of InxGa1−xN multiple quantum wells. Phys. Rev. B 59, 10283–10288 (1999).

    Article  Google Scholar 

  13. 13

    Chichibu, S., Wada, K. & Nakamura, S. Spatially resolved cathodoluminescence spectra of InGaN quantum wells. Appl. Phys. Lett. 71, 2346–2348 (1997).

    Article  Google Scholar 

  14. 14

    Kisielowski, C., Liliental-Weber, Z. & Nakamura, S. Atomic scale indium distribution in a GaN/In0.43Ga0.57N/Al0.1Ga0.9N quantum well structure. Jpn J. Appl. Phys. 1 36, 6932–6936 (1997).

    Article  Google Scholar 

  15. 15

    Narukawa, Y. et al. Role of self-formed InGaN quantum dots for exciton localization in the purple laser diode emitting at 420 nm. Appl. Phys. Lett. 70, 981–983 (1997).

    Article  Google Scholar 

  16. 16

    Im, J. S. et al. Evidence for quantum-dot-like states in GaInN/GaN quantum wells? J. Cryst. Growth 189/190, 597–600 (1998).

    Article  Google Scholar 

  17. 17

    O’Donnell, K. P., Martin, R. W. & Middleton, P. G. Origin of luminescence from InGaN diodes. Phys. Rev. Lett. 82, 237–240 (1999).

    Article  Google Scholar 

  18. 18

    Smeeton, T. M., Kappers, M. J., Barnard, J. S., Vickers, M. E. & Humphreys, C. J. Electron-beam-induced strain within InGaN quantum wells: False indium cluster detection in the transmission electron microscope. Appl. Phys. Lett. 83, 4519–4521 (2003).

    Article  Google Scholar 

  19. 19

    Chichibu, S. F., Azuhata, T., Sota, T. & Mukai, T. Localized excitons in an In0.06Ga0.94N multiple-quantum-well laser diode lased at 400 nm. Appl. Phys. Lett. 79, 341–343 (2001).

    Article  Google Scholar 

  20. 20

    Holst, J. et al. The origin of optical gain in cubic InGaN grown by molecular beam epitaxy. Appl. Phys. Lett. 76, 2832–2834 (2000).

    Article  Google Scholar 

  21. 21

    Waltereit, P. et al. Nitride semiconductors free of electrostatic fields for efficient white light-emitting diodes. Nature 406, 865–868 (2000).

    Article  Google Scholar 

  22. 22

    Chichibu, S. F. et al. Recombination dynamics of localized excitons in cubic InxGa1−xN/GaN multiple quantum wells grown by radio frequency molecular beam epitaxy on 3C-SiC substrate. J. Vac. Sci. Technol. B 21, 1856–1862 (2003).

    Article  Google Scholar 

  23. 23

    Ponce, F. A. et al. Microstructure and electronic properties of InGaN alloys. Phys. Status Solidi B 240, 273–284 (2003).

    Article  Google Scholar 

  24. 24

    Onuma, T. et al. Localized exciton dynamics in nonpolar (11.hivin.20) InxGa1−xN multiple quantum wells grown on GaN templates prepared by lateral epitaxial overgrowth. Appl. Phys. Lett. 86, 151918 (2005).

    Article  Google Scholar 

  25. 25

    Pereira, S. et al. Structural and optical properties of InGaN/GaN layers close to the critical layer thickness. Appl. Phys. Lett. 81, 1207–1209 (2002).

    Article  Google Scholar 

  26. 26

    Wu, X. H. et al. Structural origin of V-defects and correlation with localized excitonic centers in InGaN/GaN multiple quantum wells. Appl. Phys. Lett. 72, 692–694 (1998).

    Article  Google Scholar 

  27. 27

    Hangleiter, A. et al. Suppression of nonradiative recombination by V-shaped pits in GaInN/GaN quantum wells produces a large increase in the light emission efficiency. Phys. Rev. Lett. 95, 127402 (2005).

    Article  Google Scholar 

  28. 28

    Morita, D. et al. Watt-class high-output-power 365 nm ultraviolet light-emitting diodes. Jpn J. Appl. Phys. 1 43, 5945–5950 (2004).

    Article  Google Scholar 

  29. 29

    Wetzel, C., Takeuchi, T., Amano, H. & Akasaki, I. Piezoelectric Stark-like ladder in GaN/GaInN/GaN heterostructures. Jpn J. Appl. Phys. 2 38, L163–L165 (1999).

    Article  Google Scholar 

  30. 30

    Morel, A. et al. Donor-acceptor-like behavior of electron-hole pair recombinations in low-dimensional (Ga,In)N/GaN systems. Phys. Rev. B 68, 045331 (2003).

    Article  Google Scholar 

  31. 31

    Bellaiche, L., Mattila, T., Wang, L.-W., Wei, S.-H. & Zunger, A. Resonant hole localization and anomalous optical bowing in InGaN alloys. Appl. Phys. Lett. 74, 1842–1844 (1999).

    Article  Google Scholar 

  32. 32

    Kent, P. R. C. & Zunger, A. Carrier localization and the origin of luminescence in cubic InGaN alloys. Appl. Phys. Lett. 79, 1977–1979 (2001).

    Article  Google Scholar 

  33. 33

    Wang, L.-W. Calculations of carrier localization in InxGa1−xN. Phys. Rev. B 63, 245107 (2001).

    Article  Google Scholar 

  34. 34

    Walukiewicz, W. et al. Optical properties and electronic structure of InN and In-rich group III-nitride alloys. J. Cryst. Growth 269, 119–127 (2004).

    Article  Google Scholar 

  35. 35

    Onuma, T. et al. Recombination dynamics of localized excitons in Al1−xInxN epitaxial films on GaN templates grown by metalorganic vapor phase epitaxy. J. Appl. Phys. 94, 2449–2453 (2003).

    Article  Google Scholar 

  36. 36

    Onuma, T. et al. Radiative and nonradiative processes in strain-free AlxGa1−xN films studied by time-resolved photoluminescence and positron annihilation techniques. J. Appl. Phys. 95, 2495–2504 (2004).

    Article  Google Scholar 

  37. 37

    Dudiy, S. V. & Zunger, A. Type I to type II transition at the interface between random and ordered domains of AlxGa1−xN alloys. Appl. Phys. Lett. 84, 1874–1876 (2004).

    Article  Google Scholar 

  38. 38

    Chichibu, S., Azuhata, T., Sota, T. & Nakamura, S. Luminescences from localized states in InGaN epilayers. Appl. Phys. Lett. 70, 2822–2824 (1997).

    Article  Google Scholar 

  39. 39

    Hirayama, H. Quaternary InAlGaN-based high-efficiency ultraviolet light-emitting diodes. J. Appl. Phys. 97, 091101 (2005).

    Article  Google Scholar 

  40. 40

    Krause-Rehberg, R. & Leipner, H. S. Positron Annihilation in Semiconductors. Solid-State Sciences Vol. 127 (Springer, Berlin, 1999).

    Google Scholar 

  41. 41

    Coleman, P. G. Positron Beams and Their Application (World Scientific, Singapore, 2000).

    Google Scholar 

  42. 42

    Van de Walle, C. G. & Neugebauer, J. First-principles calculations for defects and impurities: Applications to III-nitrides. J. Appl. Phys. 95, 3851–3879 (2004).

    Article  Google Scholar 

  43. 43

    Wright, A. F. Interaction of hydrogen with gallium vacancies in wurtzite GaN. J. Appl. Phys. 90, 1164–1169 (2001).

    Article  Google Scholar 

  44. 44

    Stampfl, C. & Van de Walle, C. G. Theoretical investigation of native defects, impurities, and complexes in aluminum nitride. Phys. Rev. B 65, 155212 (2002).

    Article  Google Scholar 

  45. 45

    Van Veen, A. et al. VEPFIT applied to depth profiling problems. Appl. Surf. Sci. 85, 216–224 (1995).

    Article  Google Scholar 

  46. 46

    Uedono, A. et al. Study of defects in GaN grown by the two-flow metalorganic chemical vapor deposition technique using monoenergetic positron beams. J. Appl. Phys. 90, 181–186 (2001).

    Article  Google Scholar 

  47. 47

    Chichibu, S., Azuhata, T., Sota, T. & Nakamura, S. Excitonic emissions from hexagonal GaN epitaxial layers. J. Appl. Phys. 79, 2784–2786 (1996).

    Article  Google Scholar 

  48. 48

    Uedono, A. et al. Vacancy-type defects in Si-doped InN grown by plasma-assisted molecular-beam epitaxy probed using monoenergetic positron beams. J. Appl. Phys. 97, 043514 (2005).

    Article  Google Scholar 

  49. 49

    Van de Walle, C. G. & Neugebauer, J. Universal alignment of hydrogen levels in semiconductors, insulators and solutions. Nature 423, 626–628 (2003).

    Article  Google Scholar 

  50. 50

    Suski, T. et al. Light emission versus energy gap in group-III nitrides: hydrostatic pressure studies. Phys. Status Solidi B 235, 225–231 (2003).

    Article  Google Scholar 

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Acknowledgements

This work was supported in part by the 21st Century COE program ‘Promotion of Creative Interdisciplinary Materials Science for Novel Functions’ under MEXT, Japan.

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A.U. carried out the positron annihilation measurement; T.O., T.K. and T.S. carried out TRPL and CL measurements; B.A.H., A.C., P.T.F., S.K., S.P.D., J.S.S., U.K.M. and S.N. grew GaN, InGaN and AlGaN films and QWs; S.Y., S.K., H.A. and I.A. grew AlInN films; J.H. grew AlInGaN films; S.F.C. carried out several of the above measurements and analysis, and organized this research project.

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Correspondence to Shigefusa F. Chichibu.

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The authors declare no competing financial interests.

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Chichibu, S., Uedono, A., Onuma, T. et al. Origin of defect-insensitive emission probability in In-containing (Al,In,Ga)N alloy semiconductors. Nature Mater 5, 810–816 (2006). https://doi.org/10.1038/nmat1726

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