High-Performance and Temperature-Stable InGaN Single-Quantum-Well Red Light-Emitting Diodes via Selective Hydrogen Passivation

Herein, a selective passivation of p-GaN via hydrogen plasma treatment for InGaN single-quantum-well (SQW) red light-emitting diodes (LEDs) is reported. Insulating regions are formed on the p-GaN top surface via hydrogen plasma treatment, suppressing current injection beneath the p-pad and along the mesa perimeter to increase light output and mitigate non-radiative recombination. The fabricated LEDs demonstrate a high on-wafer light output power density of >88 mW cm⁻², a peak on-wafer external quantum efficiency of 0.65%, and on-wafer wall-plug efficiency of 0.41% with a 645 nm peak emission wavelength at 10 mA (7.2 A cm⁻²) current injection. Further, the temperature dependence of InGaN SQW red LEDs is compared with their AlGaInP counterparts. InGaN SQW red LEDs exhibit a high characteristic temperature of 208 K and a small redshift coefficient of 0.072 nm K⁻¹ at 72 A cm⁻² current injection, which are almost 3 and 2 times better than the characteristics of AlGaInP red LEDs, respectively.