Skip to main content
SpringerLink
Log in

Effect of Thickness Variation in High-Efficiency Ingan/Gan Light Emitting Diodes

  • Published:
MRS Online Proceedings Library Aims and scope

Abstract

We have found that InxGa(1-x)N/GaN multi-quantum-well (MQW) light emitting diodes (LEDs) having periodic thickness variation (TV) in InxGa(1-x)N active layers exhibit substantially higher optical efficiency than LEDs with uniform InxGa(1-x)N layers. In these nano-structured LEDs, the thickness variation of the active layers is shown to be more important than In composition fluctuation in quantum confinement of excitons (carriers). Detailed STEM-Z contrast analysis, where image contrast is proportional to Z2 (atomic number)2, was carried out to investigate the thickness variation as well as the spatial distribution of In. In the nanostructured LEDs, there are short-range (SR-TV, 3 to 4 nm) and long-range thickness variations (LR-TV, 50 to 100 nm) in InxGa(1-x)N layers. It is envisaged that LR-TV is the key to quantum confinement of the carriers and enhancing the optical efficiency. We propose that the LR-TV thickness variation is caused by two-dimensional strain in the InxGa(1-x)N layer below its critical thickness. The SR-TV may be caused by In composition fluctuation. The observations on thickness variation are in good agreement with model calculations based upon strain effects.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. S. Strite and H. Morkoc, J. Vac. Sci. Technol. B 10, 1237 (1992).

    Article  CAS  Google Scholar 

  2. GaN and Related Alloys- 1998 MRS Proceedings Volume 537, ed by S. J. Pearton, C. P. Kao, A. F. Wright, and T. Uenoyama( MRS Internet J. Nitride Semi Res, 4S1, 1999).

  3. S. Nakamura, Science 281, 956 (1998).

    Article  CAS  Google Scholar 

  4. S.C. Jain, M. Willander, J. Narayan, R. Van Overstraeten, J. Appl. Phys. 87, 965 (2000).

    Article  CAS  Google Scholar 

  5. Introduction to Nitride Semiconductor Blue Lasers and Light Emitting Diodes, ed. S. Nakamura, S. F. Chichibu, Taylor and Fancis, New York (2000).

  6. S. Chichibu, K. Wada, and S. Nakamura, Appl. Phys. Lett. 71, 2346 (1997).

    Article  CAS  Google Scholar 

  7. Y. Narukawa, Y. Kawakami, S. Fujita, and S. Nakamura, Phys Rev B 59, 10283 (1999).

  8. R. Singh, D. Doppalapudi, T. D. Moustakas, and L. T. Romano, Appl. Phys. Lett. 70, 1089 (1997).

    Article  CAS  Google Scholar 

  9. F. B. Naranjo, M. A. Sanchez-Garcia, F. Calle, and E. Calleja, Appl. Phys. Lett. 80, 231 (2002).

    Article  CAS  Google Scholar 

  10. N. A. El-Masry, E. L. Piner, S. X. Liu, and S. M. Bedair, Appl. Phys. Lett. 72, 40 (1998).

    Article  CAS  Google Scholar 

  11. H. Hirayama, S. Tanaka, P. Ramvall, and Y. Aoyagi, Appl. Phys. Lett. 72, 1736 (1998).

    Article  CAS  Google Scholar 

  12. J. Zhang, M. Hao, P. Li, and S. J. Chua, Appl. Phys. Lett. 80, 485 (2002).

    Article  CAS  Google Scholar 

  13. M. D. McCluskey, L. T. Romano, B. S. Krusor, D. P. Bour, N. M. Johnson, and S. Brennan, Appl. Phys. Lett. 72, 1730 (1998).

    Article  CAS  Google Scholar 

  14. L. T. Romano, M. D. McCluskey, C. G. Van de Walle, J. E. Northrup, D. P. Bour, M. Kneissi, T. Suski, and J. Jun, Appl. Phys. Lett. 75, 3950 (1999).

    Article  CAS  Google Scholar 

  15. Y. Narukawa, Y. Kawakami, M. Funato, S. Fujita, S. Nakamura, Appl. Phys. Lett. 70, 981 (1997).

    Article  CAS  Google Scholar 

  16. Y-S. Lin, K-J. Ma, C. Hsu, S-W. Feng, Y-C. Cheng, Appl. Phys. Lett. 77, 2988 (2000).

    Article  CAS  Google Scholar 

  17. S. J. Pennycook and J. Narayan, Phys. Rev. Lett. 54, 1543 (1985).

    Article  CAS  Google Scholar 

  18. S. J. Pennycook and D. E. Jesson, Ultramicroscopy 37, 14 (1991).

    Article  Google Scholar 

  19. D. J. Eaglesham and M. Cerullo, Phys. Rev. Lett. 64, 1943 (1990).

    Article  CAS  Google Scholar 

  20. S. Oktyabrsky, H. Wu, R. D. Vispute, and J. Narayan, Phil. Mag. A71, 537 (1995).

  21. D. E. Jesson, K. M. Chen, S. J. Pennycook, T. Thundat and R. J. Warmack, Phys. Rev. Lett 77, 1330 (1996).

    Article  CAS  Google Scholar 

  22. R. J. Asaro and W. A. Tiller, Metall. Trans.3, 1789 (1972).

  23. J. K. Lee, Int. Mater. Rev. 43, 221 (1997).

    Article  Google Scholar 

  24. N. P. Kobayashi, T. R. Ramchandran, P. Chen, and A. Madhukar, Appl. Phys Lett. 68, 3299 (1996).

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Materials Science and Engineering, North Carolina State University, 27695, Raleigh, NC, USA

    J. Narayan & H. Wang

  2. Kopin Corporation, 695 Myles Standish Blvd., 02780, Taunton, MA, USA

    Jinlin Ye, Schang-Jing Hon, Kenneth Fox, Jyh Chia Chen, H. K. Choi & John C. C. Fan

Authors
  1. J. Narayan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. H. Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jinlin Ye
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Schang-Jing Hon
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Kenneth Fox
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Jyh Chia Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. H. K. Choi
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. John C. C. Fan
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Narayan, J., Wang, H., Ye, J. et al. Effect of Thickness Variation in High-Efficiency Ingan/Gan Light Emitting Diodes. MRS Online Proceedings Library 743, 622 (2002). https://doi.org/10.1557/PROC-743-L6.22

Download citation

  • Published:

  • DOI: https://doi.org/10.1557/PROC-743-L6.22

Search

Navigation