Unified Model for the GaN LED Efficiency Droop
نویسندگان
چکیده
Nitride-based light-emitting diodes (LEDs) suffer from a reduction (droop) of the internal quantum efficiency with increasing injection current. This droop phenomenon is currently the subject of intense research worldwide, as it delays general lighting applications of GaN-based LEDs. Several proposals have been forwarded to explain the efficiency droop. Among the suggested droop mechanisms are defect-related recombination, Auger recombination, and electron leakage. However, different sample preparation and measurement conditions as well as the application of different models lead to a confusing and sometimes contradicting variety of efficiency droop observations and explanations. This paper combines different droop models in a simple yet unified framework and it helps to bring more clarity to the ongoing droop discussion.
منابع مشابه
Efficiency droop in nitride-based light-emitting diodes
Nitride-based light-emitting diodes (LEDs) suffer from a reduction (droop) of the internal quantum efficiency with increasing injection current. This droop phenomenon is currently the subject of intense research worldwide, as it delays general lighting applications of GaN-based LEDs. Several explanations of the efficiency droop have been proposed in recent years, but none is widely accepted. Th...
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