Effect of interface roughness on Auger recombination in semiconductor quantum wells

Abstract

Auger recombination in a semiconductor is a three-carrier process, wherein the energy from the recombination of an electron and hole pair promotes a third carrier to a higher energy state. In semiconductor quantum wells with increased carrier densities, the Auger recombination becomes an appreciable fraction of the total recombination rate and degrades luminescence efficiency. Gaining insight into the variables that influence Auger recombination in semiconductor quantum wells could lead to further advances in optoelectronic and electronic devices. Here we demonstrate the important role that interface roughness has on Auger recombination within quantum wells. Our computational studies find that as the ratio of interface roughness to quantum well thickness is increased, Auger recombination is significantly enhanced. Specifically, when considering a realistic interface roughness for an InGaN quantum well, the enhancement in Auger recombination rate over a quantum well with perfect heterointerfaces can be approximately four orders of magnitude.

Impact of Compositional Nonuniformity in (In,Ga)N -Based Light-Emitting Diodes

“…As a matter of fact, both the experimental peak energy and width are better described when alloy nonuniformity is taken into account. Nevertheless, with our work we do not intend to rule out other mechanisms, such as excitonic effects, interface roughness [22,42,43], built-in field and local field effects [16,44], which also lead to broadening and peak emission reduction. Finally, when the presence of nonuniformity is considered, a higher number of optical transitions is allowed due to the translational symmetry breaking induced by clusters.…”

Effect of Carrier Localization on Recombination Processes and Efficiency of InGaN-Based LEDs Operating in the “Green Gap”

“…One more alternative model of the Auger recombination in InGaN QWs mediated by interface roughness has been suggested in [50]. Authors of the paper have considered enhancement of Auger recombination caused by violation of the momentum selection rule and originating from fluctuations of the QW width.…”

“…Besides, the model does not regard any correlations between the width fluctuations, InGaN composition, and conditions of QW growth. Until such a correlation is established, the model of [50] seems to be ineffective for predicting trends in the LED efficiency variation inside the "green gap".…”

Effect of Dielectric Distributed Bragg Reflector on Electrical and Optical Properties of GaN-Based Flip-Chip Light-Emitting Diodes

“…The wide bandgap GaN and related materials have been extensively studied and implemented for optoelectronic devices that emit light in the spectrum between ultraviolet and visible light [1,2,3,4,5,6,7]. GaN-based light-emitting diodes (LEDs) have been extensively adopted in a number of applications such as high-resolution micro-displays, automotive lighting, optogenetics, visible light communication (VLC), and solid-state lighting.…”