Advantages of AlGaN-Based 310-nm UV Light-Emitting Diodes With Al Content Graded AlGaN Electron Blocking Layers

Yang Li; Shengchang Chen; Wu Tian; Zhihao Wu; Yanyan Fang; Jiangnan Dai; Changqing Chen

doi:10.1109/JPHOT.2013.2271718

IEEE Photonics Journal (Jan 2013)

Advantages of AlGaN-Based 310-nm UV Light-Emitting Diodes With Al Content Graded AlGaN Electron Blocking Layers

Yang Li,
Shengchang Chen,
Wu Tian,
Zhihao Wu,
Yanyan Fang,
Jiangnan Dai,
Changqing Chen

Affiliations

Yang Li: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China
Shengchang Chen: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China
Wu Tian: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China
Zhihao Wu: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China
Yanyan Fang: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China
Jiangnan Dai: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China
Changqing Chen: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, China

DOI: https://doi.org/10.1109/JPHOT.2013.2271718
Journal volume & issue: Vol. 5, no. 4
pp. 8200309 – 8200309

Abstract

Read online

In order to improve the performance of deep ultraviolet light-emitting diodes (UV LEDs), the effects of different electron blocking layers (EBLs) on the performance of AlxGa1-xN-based deep UV LEDs at 310 nm have been studied through a numerical simulation. The simulation results show that the adoption of EBLs is critical to improve the device performance. In comparison with a conventional structure using EBL with constant Al composition (0.7), the device structure with an Al-content graded AlxGa1-xN (from 0.9 to 0.4 in the growth direction) EBL possesses numerous advantages such as lower working voltage, higher internal quantum efficiency, and less efficiency droop under high-current injection. By detailedly analyzing the profiles of energy band diagrams, distributions of carrier concentration, and electron current density, the advantages of Al-content graded AlxGa1-xN EBL are attributed to the resulting lower resistivity, higher barrier for electron leakage, and simultaneously reduced barrier for hole injection compared with the conventional EBL with constant Al composition.

Published in IEEE Photonics Journal

ISSN: 1943-0655 (Online)
Publisher: IEEE
Country of publisher: United States
LCC subjects: Technology: Engineering (General). Civil engineering (General): Applied optics. Photonics; Science: Physics: Optics. Light
Website: http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=4563994

About the journal

Abstract

Keywords