Improved Hole Transport by ${\rm p}\hbox{-}{\rm In}_{x}{\rm Ga}_{1-x}{\rm N}$ Layer in Multiple Quantum Wells of Visible LEDs

Abstract

Studied is the effect of indium (In) mole fraction in p-In x Ga 1−x N:Mg layers with 0 ≤ x In ≤ 0.035 on hole injection and transport behaviors in InGaN/GaN multiple quantum wells (MQWs) using dual-wavelength and triple-wavelength active regions. Electro-optical characteristics of light-emitting diodes containing p-layers with different In content and with silicon doping in selected QW barriers (QWBs) are compared to evaluate hole transport in the active region. The results show that enhanced hole transport and corresponding more uniform distribution of holes across the MQW region are achieved by increasing x In in the p-In x Ga 1−x N:Mg layer, possibly due to modification in energy of holes by a potential barrier between the p-InGaN and GaN QWB.

Effect of lattice‐matched InAlGaN electron‐blocking layer on hole transport and distribution in InGaN/GaN multiple quantum wells of visible light‐emitting diodes

“…This efficiency droop is a common feature of III‐N LEDs and poses a major technical challenge in the development of high‐power and high‐brightness III‐N LEDs operating at high current densities. Although several possible mechanisms have been proposed, including carrier spill‐over , Auger recombination , high‐density crystalline defects , limited hole injection, transport , etc., the dominant mechanisms responsible for efficiency droop with a complete unified view have not been identified. In addition, the reported mechanisms are possibly interrelated and coupled one another and they all may partially contribute to the efficiency droop.…”

Effect of Polarization Field and Nonradiative Recombination Lifetime on the Performance Improvement of Step Stage InGaN/GaN Multiple Quantum Well LEDs

“…P to date, GaN based light emitting diode, as a green light source, is of great prospect to take the place of the incandescent lamp [1]. The researchers mainly focus on the light extraction efficiency [2] and internal quantum efficiency.…”