Current-induced degradation of high performance deep ultraviolet light emitting diodes

摘要

Lifetime measurements on single-chip, packaged 285 nm light-emitting diodes u0002LEDsu0003 performednunder constant current injection at 20 and 75 mA, were compared to the performance of unbiasednLEDs baked at the equivalent operating junction temperatures. The thermally stressed devicesnshowed a lesser degradation than those electrically stressed, indicating that elevated temperaturenalone does not cause degradation. Despite a decay to less than half of the initial power under currentninjection, time-resolved photoluminescence of the active region exhibits little change, whilencapacitance-voltage measurements imply that the reduced efficiency and power decay originatenfrom the generation of point defects near the p-side of the p-n junction. © 2010 American Institutenof Physics. u0004doi:10.1063/1.3435485