DOI QR코드

DOI QR Code

Temperature Dependence of Efficiency Droop in GaN-based Blue Light-emitting Diodes from 20 to 80℃

  • Received : 2018.09.11
  • Accepted : 2018.09.28
  • Published : 2018.10.25

Abstract

We investigate the temperature dependence of efficiency droop in InGaN/GaN multiple-quantum-well (MQW) blue light-emitting diodes (LEDs) in the temperature range from 20 to $80^{\circ}C$. When the external quantum efficiency (EQE) and the wall-plug efficiency (WPE) of the LED sample were measured as injection current and temperature varied, the droop of EQE and WPE was found to be reduced with increasing temperature. As the temperature increased from 20 to $80^{\circ}C$, the droop ratio of EQE was decreased from 16% to 14%. This reduction in efficiency droop with temperature can be interpreted by a temperature-dependent carrier distribution in the MQWs. When the carrier distribution and radiative recombination rate in MQWs were simulated and compared for different temperatures, the carrier distribution was found to become increasingly homogeneous as the temperature increased, which is believed to partly contribute to the reduction in efficiency droop with increasing temperature.

Keywords

References

  1. P. Pust, P. J. Schmidt, and W. Schnick, "A revolution in lighting," Nat. Mater. 14, 454-458 (2015). https://doi.org/10.1038/nmat4270
  2. J. Bhardwaj, J. M. Cesaratto, I. H. Wildeson, H. Choy, A. Tandon, W. A. Soer, P. J. Schmidt, B. Spinger, P. Deb, O. B. Shchekin, and W. Gotz, "Progress in high-luminance LED technology for solid-state lighting," Phys. Status Solidi A 214, 1600826 (2017). https://doi.org/10.1002/pssa.201600826
  3. J. Cho, J. H. Park, J. K. Kim, and E. F. Schubert, "White light-emitting diodes: History, progress, and future," Laser Photon. Rev. 11, 1600147 (2017). https://doi.org/10.1002/lpor.201600147
  4. 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, 354002 (2010). https://doi.org/10.1088/0022-3727/43/35/354002
  5. J. Piprek, "Efficiency droop in nitride-based light-emitting diodes," Phys. Status Solidi A 207, 2217-2225 (2010). https://doi.org/10.1002/pssa.201026149
  6. G. Verzellesi, D. Saguatti, M. Meneghini, F. Bertazzi, M. Goano, G. Meneghesso, and E. Zanoni, "Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies," J. Appl. Phys. 114, 071101 (2013). https://doi.org/10.1063/1.4816434
  7. L. Wang, J. Jin, C. Mi, Z. Hao, Y. Luo, C. Sun, Y. Han, B. Xiong, J. Wang, and H. Li, "A review on experimental measurements for understanding efficiency droop in InGaN-based light-emitting diodes," Materials 207, 1233 (2017).
  8. M. A. Hopkins, D. W. E. Allsopp, M. J. Kappers, R. A. Oliver, and C. J. Humphreys, "The ABC model of recombination reinterpreted: Impact on understanding carrier transport and efficiency droop in InGaN/GaN light emitting diodes," J. Appl. Phys. 122, 234505 (2017). https://doi.org/10.1063/1.4986434
  9. Y. C. Shen, G. O. Mueller, S. Watanabe, N. F. Gardner, A. Munkholm, and M. R. Krames, "Auger recombination in InGaN measured by photoluminescence," Appl. Phys. Lett. 91, 141101 (2007). https://doi.org/10.1063/1.2785135
  10. M. H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, and Y. Park, “Origin of efficiency droop in GaN-based light-emitting diodes,” Appl. Phys. Lett. 91, 183507 (2007). https://doi.org/10.1063/1.2800290
  11. J. I. Shim, H. Kim, D. S. Shin, and H. Y. Ryu, "An explanation of efficiency droop in InGaN-based light emitting diodes: Saturated radiative recombination rate at randomly distributed In-rich active areas," J. Korean Phys. Soc. 58, 503-508 (2011). https://doi.org/10.3938/jkps.58.503
  12. H. Y. Ryu, D. S. Shin, and J. I. Shim, "Analysis of efficiency droop in nitride light-emitting diodes by the reduced effective volume of InGaN active material," Appl. Phys. Lett. 100, 131109 (2012). https://doi.org/10.1063/1.3698113
  13. D. S. Meyaard, Q. Shan, J. Cho, E. F. Schubert, S.-H. Han, M.-H. Kim, C. Sone, S. J. Oh, and J. K. Kim, "Temperature-dependent efficiency droop of blue InGaN micro-light emitting diodes," Appl. Phys. Lett. 100, 081106 (2012). https://doi.org/10.1063/1.3688041
  14. P. Tian, J. J. D. McKendry, J. Herrnsdorf, S. Watson, R. Ferreira, I. M. Watson, E. Gu, A. E. Kelly, and M. D. Dawson, "Temperature-dependent efficiency droop of blue InGaN micro-light emitting diodes," Appl. Phys. Lett. 105, 171107 (2014). https://doi.org/10.1063/1.4900865
  15. S. H. Park and Y. T. Moon, "Temperature droop characteristics of internal quantum efficiency in InGaN/GaN quantum well light-emitting diodes," IEEE Photon. J. 6, 1600209 (2014).
  16. C. D. Santi, M. Meneghini, M. L. Grassa, B. Galler, R. Zeisel, M. Goano, S. Dominici, M. Mandurrino, F. Bertazzi, D. Robidas, G. Meneghesso, and E. Zanoni, "Role of defects in the thermal droop of InGaN-based light emitting diodes," J. Appl. Phys. 119, 094501 (2016). https://doi.org/10.1063/1.4942438
  17. F. Nippert, S. Y. Karpov, G. Callsen, B. Galler, T. Kure, C. Nenstiel, M. R. Wagner, M. Strassburg, H. J. Lugauer, and A. Hoffmann, "Temperature-dependent recombination coefficients in InGaN light-emitting diodes: Hole localization, Auger processes, and the green gap," Appl. Phys. Lett. 109, 161103 (2016). https://doi.org/10.1063/1.4965298
  18. J. Mickevicius, J. Jurkevicius, A. Kadys, G. Tamulaitis, M. Shur, M. Shatalov, J. Yang, and R. Gaska, "Temperaturedependent efficiency droop in AlGaN epitaxial layers and quantum wells," AIP Adv. 6, 045212 (2016). https://doi.org/10.1063/1.4947574
  19. K. Kim, J. Cho, D. S. Meyaard, G. B. Lin, E. F. Schubert, and J. K. Kim, "Temperature dependence of efficiency in GaInN/GaN light-emitting diodes with a GaInN underlayer," Int. J. Appl. Ceram. Technol. 13, 234-238 (2016). https://doi.org/10.1111/ijac.12483
  20. L. Zhao, D. Yan, Z. Zhang, B. Hua, G. Yang, Y. Cao, E. X. Zhang, X. Gu, and D. M. Fleetwood, "Temperature-dependent efficiency droop in GaN-based blue LEDs," IEEE Electron. Dev. Lett. 39, 528-531 (2018). https://doi.org/10.1109/LED.2018.2805192
  21. M. F. Schubert, S. Chhajed, J. K. Kim, E. F. Schubert, D. D. Koleske, M. H. Crawford, S. R. Lee, A. J. Fischer, G. Thaler, and M. A. Banas, "Effect of dislocation density on efficiency droop in GaInN/GaN light-emitting diodes," Appl. Phys. Lett. 91, 231114 (2007). https://doi.org/10.1063/1.2822442
  22. Y. H. Choi, G. H. Ryu, and H. Y. Ryu, "Evaluation of the temperature-dependent internal quantum efficiency and the light-extraction efficiency in a GaN-based blue light-emitting diode by using a rate equation model," J. Korean Phys. Soc. 69, 1286-1289 (2016). https://doi.org/10.3938/jkps.69.1286
  23. S. Tanaka, Y. Zhao, I. Koslow, C. C. Pan, H. T. Chen, J. Sonoda, S. P. DenBaars, and S. Nakamura, "Droop improvement in high current range on PSS-LEDs," Electron. Lett. 47, 335-336 (2011). https://doi.org/10.1049/el.2010.3306
  24. A. David, M. J. Grundmann, J. F. Kaeding, N. F. Gardner, T. G. Mihopoulos, and M. R. Krames, "Carrier distribution in (0001) InGaN/GaN multiple quantum well light-emitting diodes," Appl. Phys. Lett. 92, 053502 (2008). https://doi.org/10.1063/1.2839305
  25. H. Y. Ryu and J. I. Shim, "Effect of current spreading on the efficiency droop of InGaN light-emitting diodes," Opt. Express 19, 2886-2894 (2011). https://doi.org/10.1364/OE.19.002886
  26. D. S. Shin, D. P. Han, J. Y. Oh, and J. I. Shim, "Study of droop phenomena in InGaN-based blue and green lightemitting diodes by temperature-dependent electroluminescence," Appl. Phys. Lett. 100, 153506 (2012). https://doi.org/10.1063/1.3703313
  27. F. Zhang, N. Can, S. Hafiz, M. Monavarian, S. Das, V. Avrutin, U. Ozgur, and H. Morkoc, "Improvement of carrier injection symmetry and quantum efficiency in InGaN light-emitting diodes with Mg delta-doped barriers," Appl. Phys. Lett. 106, 181105 (2015). https://doi.org/10.1063/1.4919917
  28. H. Y. Ryu, K. S. Jeon, M. G. Kang, H. K. Yuh, Y. H. Choi, and J. S. Lee, "A comparative study of efficiency droop and internal electric field for InGaN blue light-emitting diodes on silicon and sapphire substrates," Sci. Rep. 7, 44814 (2017). https://doi.org/10.1038/srep44814
  29. APSYS by Crosslight Software, Inc., Burnaby, Canada, Available: http://www.crosslight.com.
  30. J. Piprek, "AlGaN polarization doping effects on the efficiency of blue LEDs," Proc. SPIE 8262, 82620E (2012).
  31. H. Y. Ryu, G. H. Ryu, Y. H. Choi, and B. J. Ma, "Modeling and simulation of efficiency droop in GaN-based blue light-emitting diodes incorporating the effect of reduced active volume of InGaN quantum wells," Curr. Appl. Phys. 17, 1298-1302 (2017). https://doi.org/10.1016/j.cap.2017.06.014
  32. V. Fiorentini, F. Bernardini, and O. Ambacher, "Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures," Appl. Phys. Lett. 80, 1204-1206 (2002). https://doi.org/10.1063/1.1448668
  33. J. Piprek, "Comparative efficiency analysis of GaN-based light-emitting diodes and laser diodes," Appl. Phys. Lett. 109, 021104 (2016). https://doi.org/10.1063/1.4958619
  34. M. Farahmand, C. Garetto, E. Bellotti, K. F. Brennan, M. Goano, E. Ghillino, G. Ghione, J. D. Albrecht, and P. P. Ruden, "Monte Carlo simulation of electron transport in the III-nitride wurtzite phase materials system: binaries and ternaries," IEEE Trans. Electron. Devices 48, 535-542 (2001). https://doi.org/10.1109/16.906448
  35. J. R. Chen, Y. C. Wu, S. C. Ling, T. S. Ko, T. C. Lu, H. C. Kuo, Y. K. Kuo, S. C. Wang, "Investigation of wavelength-dependent efficiency droop in InGaN lightemitting diodes," Appl. Phys. B 98, 779-789 (2010). https://doi.org/10.1007/s00340-009-3856-6
  36. J. Piprek, Semiconductor Optoelectronic Devices (Academic Press, 2003), Chapter 9.
  37. H. Y. Ryu and K. H. Ha, "Effect of active-layer structures on temperature characteristics of InGaN blue laser diodes," Opt. Express 16, 10849-10857 (2008). https://doi.org/10.1364/OE.16.010849
  38. H. Y. Ryu, "Investigation into the anomalous temperature characteristics of InGaN double quantum well blue laser diodes using numerical simulation," Nanoscale Res. Lett. 12, 366 (2017). https://doi.org/10.1186/s11671-017-2141-6