The limiting energy capabilities of high-power AlInGaN LEDs

The object of study in this work was the most advanced AlInGaN LEDs of the “UX : 3” design with a distributed system of reflective contacts located on the back side of the emitting chip. The current dependences of the output optical power and emission spectral characteristics, including their distribution (mapping) over the emitting surface in a wide range of operating currents up to $\sim$30 A have been studied. An analysis of the near-field emission by intensity and spectrum revealed a high uniformity of the current density distribution at all levels of excitation (no current crowding). Thus, the saturation of the optical power and the quantum efficiency droop are explained by purely internal factors, which are well described by the ABC model.