Role of the electron blocking layer in the current transport of efficient III-N light-emitting diodes

Electron blocking layers (EBLs) are commonly used to reduce the leakage current in modern multi-quantum well (MQW) InGaN light-emitting diodes (LEDs). We study the effect of the EBL and doping on the operation and efficiency of LEDs. We simulate both conventional MQW LEDs with AlGaN EBL, LEDs with quaternary AlInGaN EBL and LEDs without EBL. We show that the elimination of the polarization charges at the EBL interface greatly enhances the injection efficiency and that the hole injection in MQW lattice can be optimized by doping. The efficiency droop limiting the high power operation is also analyzed to determine the underlying mechanisms in the simulated MQW structures. Based on these results, we discuss the measures to increase the overall efficiency MQW structures.

[1]  K. Delaney,et al.  Auger recombination rates in nitrides from first principles , 2009, 0904.3559.

[2]  Michael R. Krames,et al.  Auger recombination in InGaN measured by photoluminescence , 2007 .

[3]  M. H. Crawford,et al.  Internal quantum efficiency and non-radiative recombination coefficient of GaInN/GaN multiple quantum wells with different dislocation densities , 2009, 2009 Conference on Lasers and Electro-Optics and 2009 Conference on Quantum electronics and Laser Science Conference.

[4]  M. Craford,et al.  Status and Future of High-Power Light-Emitting Diodes for Solid-State Lighting , 2007, Journal of Display Technology.

[5]  James S. Speck,et al.  Prospects for LED lighting , 2009 .

[6]  E. Schubert,et al.  Polarization-matched GaInN∕AlGaInN multi-quantum-well light-emitting diodes with reduced efficiency droop , 2008 .

[7]  K. A. Bulashevich,et al.  Is Auger recombination responsible for the efficiency rollover in III-nitride light-emitting diodes? , 2008 .

[8]  G. Chen,et al.  Performance of high‐power III‐nitride light emitting diodes , 2008 .

[9]  Alexander I. Zhmakin,et al.  Simulation of visible and ultra-violet group-III nitride light emitting diodes , 2006, J. Comput. Phys..

[10]  E. Fred Schubert,et al.  Origin of efficiency droop in GaN-based light-emitting diodes , 2007 .

[11]  Hadis Morkoç,et al.  On the efficiency droop in InGaN multiple quantum well blue light emitting diodes and its reduction with p-doped quantum well barriers , 2008 .