Conclusion

1. Conclusion • In summary, the EQE droop point shifted toward higher current density, with the slope of the EQE droop also diminishing, and the forward voltage drop upon decreasing the quantum barriers of InGaN/GaN MQWs.We conclude that the enhanced performance was due to a more-uniform carrier distribution when NQBs were present. This uniform carrier distribution would decrease the carrier density in the active layer at a given current density . • Furthermore, from our special structure design of LED A and B, again, experimentally demonstrated the more-uniform carrier distribution in NQBs LED. 8

2. Reference • 二極體I-V關係式http://tw.knowledge.yahoo.com/question/question?qid=1608050905312 • pn接面二極體的電流電壓特性http://ezphysics.nchu.edu.tw/prophys/electron/lecturenote/3_2.pdf • M. Maier, K. Köhler, M. Kunzer, W. Pletschen, and J. Wagner, “Reduced nonthermal rollover of wide-well GaInN light-emitting diodes,”Appl. Phys. Lett., vol. 94, no. Art. no. 041103, 2009. • Improved Carrier Distributions by Varying BarrierThickness for InGaN/GaN LEDs S. F. Yu, Ray-Ming Lin, S. J. Chang, Senior Member, IEEE, J. R. Chen, J. Y. Chu, C. T. Kuo, and Z. Y. Jiao • Improved Carrier Distributions by Varying Barrier Thickness for InGaN/GaN LEDsS. F. Yu, Ray-Ming Lin, S. J. Chang, Senior Member, IEEE, J. R. Chen, J. Y. Chu, C. T. Kuo, and Z. Y. Jiao 9

3. Thanks for your attention