Improved performance of GaN-based blue light emitting diodes with InGaN/GaN multilayer barriers

Hun Jae Chung; Rak Jun Choi; Min Ho Kim; Jae Woong Han; Young Min Park; Yu Seung Kim; Ho Sun Paek; Cheol Soo Sone; Yong Jo Park; Jong Kyu Kim; Schubert, E. Fred
December 2009
Applied Physics Letters;12/14/2009, Vol. 95 Issue 24, p241109
Academic Journal
Multi-layer barrier structure is suggested as an alternative approach to single-layer polarization matching barrier structure for the reduction of efficiency droop. Time resolved photoluminescence measurement showed that polarization field was reduced by 19% in the multilayer barrier light emitting diodes structures. Optical power measurements on packaged devices showed overall increase of external quantum efficiency for all currents up to the current density of 150 A/cm2. Increase of optical power is attributed to reduced polarization and decreased current overflow to p-side cladding layers. These results provide additional evidences that polarization is important in addressing the droop problem.


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