The Emission Properties of Light Emitting Diodes using InGaN/AlGaN/GaN Multiple Quantum Wells

Abstract

Luminescence spectra of Light Emitting Diodes (LEDs) with Multiple Quantum Wells (MQWs) were studied at currents J = 0.15 µ A -150 mA. A high quantum efficiency at low J is caused by a low probability of the tunnel current J (which is maximum at J m ≈ 0.5-1.0 mA). J(V) curves were measured in the range J= 10

Simulation of visible and ultra-violet group-III nitride light emitting diodes

“…At the moment, the dislocation impact on the LED efficiency and other characteristics is not examined in detail. And, the question that is still obscure concerns the role of a tunnelling current frequently observed in InGaN blue and, especially, green LEDs (see for instance [11]). …”

Electroluminescence Properties of InGaN/AlGaN/GaN Light Emitting Diodes with Quantum Wells

“…A part ~(J/J 1 ) 0.5 is sufficient between an exponential (injection) and a linear parts, in the range J=2÷30 mA, at usual working currents [1]. Distributions of charged centers in p-regions of InGaN/AlGaN/GaN p-n-heterostructures with MQWs and SQWs are shown, see Fig.…”

“…Low currents could be understood as a tunnel component; tunnel currents in these LEDs play some role at J 3-4 orders of magnitude lower than that for SQWbased LEDs [2][3][4][5]7]; J(V) curves of SQW-based LEDs differed from MQW-based LEDs because of a wider active layer [1]. A good approximation of the J(V) curves for MQW LEDs was done when not only a series resistance R s at the linear part at higher J was taken into account, but also the quadratic part: J ( V-V 1 )…”

“…We describe the main lines in spectra with a model previously applied for fitting the spectra of LEDs with SQW [1][2][3]. The model implies that an effective radiative recombination takes place when carriers of both singes are injected into the active layer at voltages on the layer U < V, U close to ϕ k .…”