physica status solidi (a) · 2009 · 91 citations · 9 references
EngineeringElectrical EngineeringMaterials ScienceOptoelectronicsPhotonicsSemiconductor DevicesLaser DiodesLight SourcesLight-emitting DiodesQuantum DotsQuantum Well DevicesQuantum WellsBlue Light-emitting DiodesCharge Carrier DensityGallium Nitride Light-emitting DiodesGreen Light-emitting DiodesLight-emitting DevicesOptical Loss MechanismsQuantum Well Light-emitting DiodesQuantum Well Structures
Abstract Green InGaN LEDs showed great improvements over the last decade, but still perform not as good as blue InGaN LEDs. Brightness, Efficiency and sub‐linearity of brightness versus driving current (“droop”) are significantly lower for a 530 nm green LED than for a 440 nm blue LED. Assuming an indirect Auger effect as one of the major loss mechanisms in InGaN LEDs, a reduction of the carrier density per emitting well is the key for efficiency improvement for green LEDs. An optimized multiple quantum well (MQW) structure with multiple emitting wells at 525 nm is compared to a single quantum well LED structure. A color‐coding scheme was used to investigate MQW operation: up to four MQWs contribute to the green emission at 525 nm. Packaged 1 × 1 mm 2 ThinGaN ® chips emit up to 109 lm (209 mW) at 350 mA and 170 lm (339 mW) at 700 mA, the efficacy was 90 lm/W and 66 lm/W, respectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
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Origin of efficiency droop in GaN-based light-emitting diodes
Minho Kim, M. Schubert, Qi Dai et al. · Applied Physics Letters · 2007 · 1.3K citations · Full text
Engineering, Electrical Engineering, Materials Engineering +17
Auger recombination in InGaN measured by photoluminescence
Yinchu Shen, Gerd Mueller, Satoshi Watanabe et al. · Applied Physics Letters · 2007 · 1.1K citations