An explanation for invalidity of working currents' derating on improving light-emitting diode devices' reliability

Derating of the working current level does not work for improving GaN-based light-emitting diode (LED) devices' reliability. The present work demonstrates that it is not the levels but the specific components of the applied electrical currents weighing more on LEDs' degradation. Existing defects are sources for tunneling currents and Shockley-Read-Hall (SRH) non-radiative recombination current, and the component of tunneling currents and SRH non-radiative recombination current in the applied electrical current will in turn induce fast increase of defect density. The current component from electron tunneling to deep levels in the vicinity of mixed/screw dislocations will affect more on LEDs' degradation than other components, such as heavy-hole tunneling via intermediate state. In a whole, the overflow leakage current from the active region and Auger recombination currents in the applied electrical current will generate positive effects to alleviate LEDs' degradation.

[1]  S. Buso,et al.  Performance Degradation of High-Brightness Light Emitting Diodes Under DC and Pulsed Bias , 2008, IEEE Transactions on Device and Materials Reliability.

[2]  Xian-An Cao,et al.  Electrical characteristics of InGaN∕GaN light-emitting diodes grown on GaN and sapphire substrates , 2004 .

[3]  Gang Wang,et al.  Efficiency degradation behaviors of current/thermal co-stressed GaN-based blue light emitting diodes with vertical-structure , 2012 .

[4]  R. Olshansky,et al.  Measurement of radiative and nonradiative recombination rates in InGaAsP and AlGaAs light sources , 1984 .

[5]  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 .

[6]  E. Schubert,et al.  On the temperature dependence of electron leakage from the active region of GaInN/GaN light-emitting diodes , 2011 .

[7]  Meng Zhang,et al.  Direct measurement of auger recombination in In0.1Ga0.9N/GaN quantum wells and its impact on the efficiency of In0.1Ga0.9N/GaN multiple quantum well light emitting diodes , 2009 .

[8]  W. Read,et al.  Statistics of the Recombinations of Holes and Electrons , 1952 .

[9]  S. Goto,et al.  Dislocation related issues in the degradation of GaN-based laser diodes , 2004, IEEE Journal of Selected Topics in Quantum Electronics.

[10]  Shuji Nakamura,et al.  Measurement of electron overflow in 450 nm InGaN light-emitting diode structures , 2009 .

[11]  Gaudenzio Meneghesso,et al.  Influence of short-term low current dc aging on the electrical and optical properties of InGaN blue light-emitting diodes , 2006 .

[12]  Jeong-Hyeon Choi,et al.  Life-time estimation of high-power blue light-emitting diode chips , 2009, Microelectron. Reliab..

[13]  Dunjun Chen,et al.  Efficiency droop behavior of direct current aged GaN-based blue light-emitting diodes , 2009 .

[14]  Paddy K. L. Chan,et al.  Physical mechanisms for hot-electron degradation in GaN light-emitting diodes , 2010 .

[15]  Sergey Bychikhin,et al.  Low-frequency noise sources in as-prepared and aged GaN-based light-emitting diodes , 2005 .

[16]  Eugene B. Yakimov,et al.  Two channels of non-radiative recombination in InGaN/GaN LEDs , 2009 .

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

[18]  C. L. Reynolds,et al.  Tunneling entity in different injection regimes of InGaN light emitting diodes , 2008 .

[19]  A. David,et al.  Droop in InGaN light-emitting diodes: A differential carrier lifetime analysis , 2010 .