中国物理B ›› 2019, Vol. 28 ›› Issue (1): 18503-018503.doi: 10.1088/1674-1056/28/1/018503

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Efficiency enhancement of ultraviolet light-emitting diodes with segmentally graded p-type AlGaN layer

Lin-Yuan Wang(王林媛), Wei-Dong Song(宋伟东), Wen-Xiao Hu(胡文晓), Guang Li(李光), Xing-Jun Luo(罗幸君), Hu Wang(汪虎), Jia-Kai Xiao(肖稼凯), Jia-Qi Guo(郭佳琦), Xing-Fu Wang(王幸福), Rui Hao(郝锐), Han-Xiang Yi(易翰翔), Qi-Bao Wu(吴启保), Shu-Ti Li(李述体)   

  1. 1 Guangdong Engineering Research Center of Optoelectronic Functional Materials and Devices, South China Normal University, Guangzhou 510631, China;
    2 School of Intelligent Manufacture and Equipment, Shenzhen Institute of Information Technology, Shenzhen 518172, China;
    3 Guangdong Deli Semiconductor Co., Ltd, Jiangmen 529000, China
  • 收稿日期:2018-06-28 修回日期:2018-09-13 出版日期:2019-01-05 发布日期:2019-01-05
  • 通讯作者: Qi-Bao Wu, Shu-Ti Li E-mail:wuqb@sziit.edu.cn;lishuti@scnu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61874161 and 11474105), the Science and Technology Program of Guangdong Province, China (Grant Nos. 2017B010127001 and 2015B010105011), the Education Department Project of Guangdong Province, China (Grant No. 2017KZDXM022), the Science and Technology Project of Guangzhou City, China (Grant No. 201607010246), the Program for Changjiang Scholars and Innovative Research Team in Universities of China (Grant No. IRT13064), the Science and Technology Project of Shenzhen City, China (Grant No. GJHZ20180416164721073), and the Science and Technology Planning of Guangdong Province, China (Grant No. 2015B010112002).

Efficiency enhancement of ultraviolet light-emitting diodes with segmentally graded p-type AlGaN layer

Lin-Yuan Wang(王林媛)1, Wei-Dong Song(宋伟东)1, Wen-Xiao Hu(胡文晓)1, Guang Li(李光)1, Xing-Jun Luo(罗幸君)1, Hu Wang(汪虎)1, Jia-Kai Xiao(肖稼凯)1, Jia-Qi Guo(郭佳琦)1, Xing-Fu Wang(王幸福)1, Rui Hao(郝锐)3, Han-Xiang Yi(易翰翔)3, Qi-Bao Wu(吴启保)2, Shu-Ti Li(李述体)1   

  1. 1 Guangdong Engineering Research Center of Optoelectronic Functional Materials and Devices, South China Normal University, Guangzhou 510631, China;
    2 School of Intelligent Manufacture and Equipment, Shenzhen Institute of Information Technology, Shenzhen 518172, China;
    3 Guangdong Deli Semiconductor Co., Ltd, Jiangmen 529000, China
  • Received:2018-06-28 Revised:2018-09-13 Online:2019-01-05 Published:2019-01-05
  • Contact: Qi-Bao Wu, Shu-Ti Li E-mail:wuqb@sziit.edu.cn;lishuti@scnu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61874161 and 11474105), the Science and Technology Program of Guangdong Province, China (Grant Nos. 2017B010127001 and 2015B010105011), the Education Department Project of Guangdong Province, China (Grant No. 2017KZDXM022), the Science and Technology Project of Guangzhou City, China (Grant No. 201607010246), the Program for Changjiang Scholars and Innovative Research Team in Universities of China (Grant No. IRT13064), the Science and Technology Project of Shenzhen City, China (Grant No. GJHZ20180416164721073), and the Science and Technology Planning of Guangdong Province, China (Grant No. 2015B010112002).

摘要:

AlGaN-based ultraviolet light-emitting diodes (UV-LEDs) have attracted considerable interest due to their wide range of application fields. However, they are still suffering from low light out power and unsatisfactory quantum efficiency. The utilization of polarization-doped technique by grading the Al content in p-type layer has demonstrated its effectiveness in improving LED performances by providing sufficiently high hole concentration. However, too large degree of grading through monotonously increasing the Al content causes strains in active regions, which constrains application of this technique, especially for short wavelength UV-LEDs. To further improve 340-nm UV-LED performances, segmentally graded Al content p-AlxGa1-xN has been proposed and investigated in this work. Numerical results show that the internal quantum efficiency and output power of proposed structures are improved due to the enhanced carrier concentrations and radiative recombination rate in multiple quantum wells, compared to those of the conventional UV-LED with a stationary Al content AlGaN electron blocking layer. Moreover, by adopting the segmentally graded p-AlxGa1-xN, band bending within the last quantum barrier/p-type layer interface is effectively eliminated.

关键词: AlGaN, ultraviolet light-emitting diodes, polarization-doped p-type layer

Abstract:

AlGaN-based ultraviolet light-emitting diodes (UV-LEDs) have attracted considerable interest due to their wide range of application fields. However, they are still suffering from low light out power and unsatisfactory quantum efficiency. The utilization of polarization-doped technique by grading the Al content in p-type layer has demonstrated its effectiveness in improving LED performances by providing sufficiently high hole concentration. However, too large degree of grading through monotonously increasing the Al content causes strains in active regions, which constrains application of this technique, especially for short wavelength UV-LEDs. To further improve 340-nm UV-LED performances, segmentally graded Al content p-AlxGa1-xN has been proposed and investigated in this work. Numerical results show that the internal quantum efficiency and output power of proposed structures are improved due to the enhanced carrier concentrations and radiative recombination rate in multiple quantum wells, compared to those of the conventional UV-LED with a stationary Al content AlGaN electron blocking layer. Moreover, by adopting the segmentally graded p-AlxGa1-xN, band bending within the last quantum barrier/p-type layer interface is effectively eliminated.

Key words: AlGaN, ultraviolet light-emitting diodes, polarization-doped p-type layer

中图分类号:  (Light-emitting devices)

  • 85.60.Jb
73.40.Kp (III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions) 78.20.Bh (Theory, models, and numerical simulation) 87.16.ad (Analytical theories)