Investigations on deep ultraviolet light-emitting diodes with quaternary AlInGaN streamlined quantum barriers for reducing polarization effect. (September 2020)

• Record Type: Journal Article
• Authors: Li, Kai; Zeng, Ni; Liao, Fengbo; Yin, YiAn
• Is Part Of: Superlattices and microstructures. Volume 145(2020)
• Publication Date: 2020-09
• Subjects: Deep ultraviolet light-emitting diode -- Quaternary AlInGaN -- Streamlined quantum barriers -- Polarization -- Efficiency droop -- Radiation recombination; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2020.106601
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: The characteristics of AlGaN-based deep ultraviolet light-emitting diodes (UV LEDs) with quaternary AlInGaN streamlined quantum barriers (QBs) are investigated in this paper. The simulated results show that the light output power and the internal quantum efficiency (IQE) of deep UV LEDs with AlInGaN streamlined QBs have been improved obviously, and the efficiency droop effect has been significantly alleviated. After in-depth study, it is shown that quaternary AlInGaN streamlined QBs is designed to reduce the polarization charge density between quantum wells (QWs) and QBs, and relieve band bending. In addition, the streamline barrier can reduce the kinetic energy of injected carriers, and improve the probability of the carriers being bounced back to the quantum wells, so as to enhance the capture of carriers in the quantum wells. As a result, the recombination rate of electron and hole in the QWs is enhanced, the light output power and the IQE are improved, and the efficiency droop effect is alleviated. Highlights: Quaternary AlInGaN streamlined quantum barriers are used on AlGaN-based deep ultraviolet light-emitting diodes. The light output power is 4.35 times higher than that of conventional structure. The efficiency droop has been reduced to 0.54%, which is 88 times lower than that of conventional structure. The polarization charge density between quantum wells and quantum barriers decreases significantly. The bending of energy band is obviously alleviated and the radiation recombination efficiency is obviously enhanced.