Origin of efficiency droop in GaN-based light-emitting diodes
Year: 2007
Type: article
Abstract: The efficiency droop in GaInN∕GaN multiple-quantum well (MQW) light-emitting diodes is investigated. Measurements show that the efficiency droop, occurring under high injection conditions, is unrelated to junction temperature. Furthermore, the photoluminescence output as a function of excitation power shows no droop, indicating that the droop is not related to MQW efficiency but rather to the recombination of carriers outside the MQW region. Simulations show that polarization fields in the MQW and electron blocking layer enable the escape of electrons from the MQW region and thus are the physical origin of the droop. It is shown that through the use of proper quaternary AlGaInN compositions, polarization effects are reduced, thereby minimizing droop and improving efficiency.
Source: Applied Physics Letters
DOI: 10.1063/1.2800290
Authors: Min-Ho Kim, Martin F. Schubert, Qi Dai, Jong Kyu Kim, E. Fred Schubert, Joachim Piprek, Yongjo Park
Institutions: Rensselaer Polytechnic Institute, Samsung (South Korea)
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2034186025