Analysis of 270/290/330-nm AlGaN-Based Deep Ultraviolet Light-Emitting Diodes With Different Al Content in Quantum Wells and Barriers

• Published in: IEEE photonics journal Vol. 7; no. 6; pp. 1 - 7
• Main Authors: Yang, G. F., Zhang, Q., Wang, J., Gao, S. M., Zhang, R., Zheng, Y. D.
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.12.2015; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: AlGaN; Aluminum; Aluminum gallium nitride; Aluminum gallium nitrides; Barriers; deep ultraviolet; Light emitting diodes; Mathematical model; numerical simulation; Optical polarization; Photonics; Power generation; Quantum well devices; Quantum wells; Ultraviolet; Volt-ampere characteristics; Wide band gap semiconductors; light-emitting diodes (LEDs); deep ultraviolet; numerical simulation; AlGaN
• ISSN: 1943-0655; 1943-0647
• DOI: 10.1109/JPHOT.2015.2491604

The optical and electrical properties of 270/290/330-nm AlGaN-based deep ultraviolet (UV) light-emitting diodes (LEDs) with different Al content in quantum wells and barriers have been investigated systematically. Based on the experimental and numerical study, it is observed that the UV LEDs with longer wavelength and lower Al composition in AlGaN multiple quantum wells (MQWs) possess less dislocation density, higher light output power, and external quantum efficiency. Large ideality factors calculated from the I-V curves and simulated energy band profiles indicate that the current in the deep UV LEDs with high Al content is dominated by tunneling mechanism, which is attributed to the resulting potential drop in the active region caused by large polarization field in AlGaN MQWs.