Reduction in Thermal Droop Using Thick Single-Quantum-Well Structure in Semipolar (20\bar{2}\bar{1}) Blue Light-Emitting Diodes

High-Power, Low-Efficiency-Droop Semipolar (20\bar{2}\bar{1}) Single-Quantum-Well Blue Light-Emitting Diodes

We demonstrate a small-area (0.1mm) semipolar (20 2 1) blue (447 nm) light-emitting diode (LED) with high light output power (LOP) and external quantum efficiency (EQE) by utilizing a single 12-nm-thick InGaN quantum well. The LED had pulsed LOPs of 140, 253, 361, and 460mW, and EQEs of 50.1, 45.3, 43.0, and 41.2%, at current densities of 100, 200, 300, and 400A/cm, respectively. The device sho...

Analysis of low efficiency droop of semipolar InGaN quantum well light-emitting diodes by modified rate equation with weak phase-space filling effect

High-Efficiency Single-Quantum-Well Green and Yellow-Green Light-Emitting Diodes on Semipolar (20\bar{2}1) GaN Substrates

We demonstrate high-efficiency green and yellow-green single-quantum-well light-emitting diodes (LEDs) grown on semipolar (20 21) GaN substrates by metal organic chemical vapor deposition. The output power and external quantum efficiency at a driving current of 20mA under a pulsed condition with a 10% duty cycle are 9.9mW and 20.4% for the green LED and 5.7mW and 12.6% for the yellow-green LED,...

High-power low-droop violet semipolar ( 30 3 ̄ 1 ̄ ) InGaN/GaN light-emitting diodes with thick active layer design

Blue light emitting diode exceeding 100 % quantum efficiency

1 Introduction GaN-based light-emitting diodes (LEDs) deliver the desired high efficiency only at relatively low injection current density [1]. At the elevated current densities required in practical high-brightness applications , the efficiency is substantially reduced. This efficiency droop phenomenon has been intensely investigated for a number of years, but the physical mechanisms behind it...