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

doi:10.1088/1674-1056/28/1/018503

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-Al_xGa_1-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-Al_xGa_1-xN, band bending within the last quantum barrier/p-type layer interface is effectively eliminated.

Keywords: AlGaN ultraviolet light-emitting diodes polarization-doped p-type layer

Received: 28 June 2018
Revised: 13 September 2018
Accepted manuscript online:

PACS:	85.60.Jb	(Light-emitting devices)
	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)

Fund:

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).

Corresponding Authors: Qi-Bao Wu, Shu-Ti Li
E-mail: wuqb@sziit.edu.cn;lishuti@scnu.edu.cn

Cite this article:

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) Efficiency enhancement of ultraviolet light-emitting diodes with segmentally graded p-type AlGaN layer 2019 Chin. Phys. B 28 018503

[1]	Hirayama H, Yatabe T, Noguchi N, Ohashi T and Kamata N 2007 Appl. Phys. Lett. 91 091101
[2]	Hirayama H, Noguchi N, Yatabe T and Kamata N 2009 Int. J. Surg. 7 180
[3]	Piprek J 2012 Opt. Quantum Electron. 44 67
[4]	Zhang Y, Krishnamoorthy S, Akyol F, Allerman A A, Moseley M W, Armstrong A M and Rajan S 2016 Appl. Phys. Lett. 109 082101
[5]	Pimputkar S, Speck J S, Denbaars S P and Nakamura S 2009 Nat. Photon. 3 180
[6]	Bao X, Sun P, Liu S, Ye C, Li S and Kang J 2015 IEEE Photon. J. 7 1
[7]	Lin B C, Wang C H, Lin C C, Chiu C H, Kuo H C, Chen K J, Shih M H, Lee P T, Kuo Y K and Lan Y P 2014 Opt. Express 22 463
[8]	Zhang Z H, Tiam T S, Kyaw Z, Liu W, Ji Y, Ju Z, Zhang X, Wei S X and Volkan D H 2013 Appl. Phys. Lett. 103 263501
[9]	Lei Y, Liu Z Q, He M, Yi X Y, Wang J X, Li J M, Zheng S W and Li S T 2015 J. Semicond. 36 054006
[10]	Cai J X, Sun H Q, Zheng H, Zhang P J and Guo Z Y 2014 Chin. Phys. B 23 058502
[11]	Zhang Y, Yu L, Li K, Pi H, Diao J, Wang X, Shen Y, Zhang C, Hu W and Song W 2015 Superlattices Microstruct. 82 151
[12]	Hu W X, Qin P, Song W D, Zhang C Z, Wang R P, Zhao L L, Xia C, Yuan S Y, Yin Y A and Li S T 2016 S Superlattices Microstruct. 97 353
[13]	Simon J, Protasenko V, Lian C, Xing H and Jena D 2010 Science 327 60
[14]	Gao L, Xie F and Yang G 2014 Superlattices Microstruct. 71 1
[15]	Zhang L, Wei X C, Liu N X, Lu H X, Zeng J P, Wang J X, Zeng Y P and Li J M 2011 Appl. Phys. Lett. 98 101110
[16]	Kuo Y K, Chang J Y, Chang H T, Chen F M, Shih Y H and Liou B T 2017 IEEE J. Quantum Electron. 53 1
[17]	Khokhlev O V, Bulashevich K A and Karpov S Y 2013 Phys. Status Solidi 210 1369
[18]	Li Y, Chen S, Tian W, Wu Z, Fang Y, Dai J and Chen C 2013 IEEE Photon. J. 5 8200309

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

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