Edge and Defect Luminescence of Powerful Ultraviolet InGaN/GaN Light-Emitting Diodes
XX Международный Симпозиум “Нанофизика и наноэлектроника”
14-18 Mar 2016
, E-ISSN: 1090-6479
Novosibirsk State Technical University, Novosibirsk, 630073 Russia
Rzhanov Institute of Semiconductor Physics, Russian Academy of Science, Siberian Branch, Novosibirsk, 630090 Russia
Ural Federal University, Yekaterinburg, 620002 Russia
The spectrum of ultraviolet (UV) InGaN/GaN light-emitting diodes and its dependence on the current flowing through the structure are studied. The intensity of the UV contribution to the integrated diode luminescence increases steadily with increasing density of current flowing through the structure, despite a drop in the emission quantum efficiency. The electroluminescence excitation conditions that allow the fraction of UV emission to be increased to 97% are established. It is shown that the nonuniform generation of extended defects, which penetrate the active region of the light-emitting diodes as the structures degrade upon local current overheating, reduces the integrated emission intensity but does not affect the relative intensity of diode emission in the UV (370 nm) and visible (550 nm) spectral ranges.