| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 748918 | Solid-State Electronics | 2011 | 5 Pages |
The efficiency droop behavior of GaN-based light emitting diodes (LEDs) is studied when the LEDs are under reverse-current and high-temperature stress tests respectively. It is found that reverse-current stress mainly induces additional non-radiative recombination centers within the active region of InGaN/GaN multiple quantum wells, which degrade the overall efficiency of the GaN LED under test but push the peak-efficiency-current towards higher magnitude. The up-shift of peak-efficiency-current can be explained by a rate-equation model in which the newly-created defects by reverse-current stress enlarge the dominant low-current region of non-radiative recombinations. Comparatively, high-temperature stress mainly increases the series resistance of the LED under test. Although the overall efficiency of the GaN LED also drops, there is no shift of peak-efficiency-current induced by the high-temperature stress.
Research highlights► Efficiency droop of GaN LEDs was studied under reverse-current and high-temperature stress. ► Reverse-current stress could cause an up-shift of peak-efficiency-current of the LEDs. ► High-temperature stress has no impact on the efficiency roll-off point. ► The observations can be explained by a rate-equation model.
