Efficiency droop suppression in InGaN-based blue LEDs: Experiment and numerical modelling

In this paper, we report on the results of experimental and theoretical study of a promising way for suppression of the efficiency droop with current in InGaN-based light emitting diodes. Simulations carried out using a drift-diffusion approach with quantum-mechanical corrections clearly show that non-radiative Auger recombination is the principal mechanism limiting the device performance at high-injection level. New design of LED heterostructure with short-period superlattice in the active region is proposed and assessed theoretically. Experimentally, the implementation of the structure design in high-power devices has resulted in substantial suppression of the efficiency droop compared to conventional multiquantum-well InGaN LEDs. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim