中国物理B ›› 2018, Vol. 27 ›› Issue (11): 114401-114401.doi: 10.1088/1674-1056/27/11/114401

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Effect of graphene/ZnO hybrid transparent electrode on characteristics of GaN light-emitting diodes

Jun-Tian Tan(谭竣天), Shu-Fang Zhang(张淑芳), Ming-Can Qian(钱明灿), Hai-Jun Luo(罗海军), Fang Wu(吴芳), Xing-Ming Long(龙兴明), Liang Fang(方亮), Da-Peng Wei(魏大鹏), Bao-Shan Hu(胡宝山)   

  1. 1 State Key Laboratory of Mechanical Transmission, Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing 400044, China;
    2 College of Software, Chongqing College of Electronic Engineering, Chongqing 401331, China;
    3 College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 400047, China;
    4 Chongqing Engineering Research Center of Graphene Film Manufacturing, Chongqing 401331, China;
    5 College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China
  • 收稿日期:2018-03-30 修回日期:2018-07-20 出版日期:2018-11-05 发布日期:2018-11-05
  • 通讯作者: Shu-Fang Zhang, Hai-Jun Luo, Liang Fang E-mail:roseymcn2000@foxmail.com;lhj19830330@126.com;lfang@cqu.edu.cn
  • 基金资助:

    Project supported by the National High Technology Research and Development Program of China (Grant No. 2015AA034801), the Foundation of the State Key Laboratory of Mechanical Transmission of Chongqing University, China (Grant Nos. SKLMT-ZZKT-2017M15 and SKLM-ZZKT-2015Z16), the National Natural Science Foundation of China (Grant Nos. 11544010, 11374359, 11304405, and 1155305), the Natural Science Foundation of Chongqing, China (Grant Nos. cstc2015jcyjA50035 and cstc2015jcyjA1660), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2018CDJDWL0011, 106112017CDJQJ328839, 106112016CDJZR288805, and 106112015CDJXY300002), and the Sharing Fund of Large-Scale Equipment of Chongqing University, China (Grant Nos. 201612150094, 201712150005, 201712150006, and 201712150010).

Effect of graphene/ZnO hybrid transparent electrode on characteristics of GaN light-emitting diodes

Jun-Tian Tan(谭竣天)1, Shu-Fang Zhang(张淑芳)2, Ming-Can Qian(钱明灿)1, Hai-Jun Luo(罗海军)1,3, Fang Wu(吴芳)1, Xing-Ming Long(龙兴明)3, Liang Fang(方亮)1, Da-Peng Wei(魏大鹏)4, Bao-Shan Hu(胡宝山)5   

  1. 1 State Key Laboratory of Mechanical Transmission, Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing 400044, China;
    2 College of Software, Chongqing College of Electronic Engineering, Chongqing 401331, China;
    3 College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 400047, China;
    4 Chongqing Engineering Research Center of Graphene Film Manufacturing, Chongqing 401331, China;
    5 College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China
  • Received:2018-03-30 Revised:2018-07-20 Online:2018-11-05 Published:2018-11-05
  • Contact: Shu-Fang Zhang, Hai-Jun Luo, Liang Fang E-mail:roseymcn2000@foxmail.com;lhj19830330@126.com;lfang@cqu.edu.cn
  • Supported by:

    Project supported by the National High Technology Research and Development Program of China (Grant No. 2015AA034801), the Foundation of the State Key Laboratory of Mechanical Transmission of Chongqing University, China (Grant Nos. SKLMT-ZZKT-2017M15 and SKLM-ZZKT-2015Z16), the National Natural Science Foundation of China (Grant Nos. 11544010, 11374359, 11304405, and 1155305), the Natural Science Foundation of Chongqing, China (Grant Nos. cstc2015jcyjA50035 and cstc2015jcyjA1660), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2018CDJDWL0011, 106112017CDJQJ328839, 106112016CDJZR288805, and 106112015CDJXY300002), and the Sharing Fund of Large-Scale Equipment of Chongqing University, China (Grant Nos. 201612150094, 201712150005, 201712150006, and 201712150010).

摘要:

In order to reduce the Schottky barrier height and sheet resistance between graphene (Gr) and the p-GaN layers in GaN-based light-emitting diodes (LEDs), conductive transparent thin films with large work function are required to be inserted between Gr and p-GaN layers. In the present work, three kinds of transparent conductive oxide (TCO) zinc oxide (ZnO) films, Al-, Ga-, and In-doped ZnO (AZO, GZO, and IZO), are introduced as a bridge layer between Gr and p-GaN, respectively. The influence of different combinations of Gr/ZnO hybrid transparent conducting layers (TCLs) on the optical and thermal characteristics of the GaN-LED was investigated by the finite element method through COMSOL software. It is found that both the TCL transmittance and the surface temperature of the LED chip reduce with the increase in Gr and ZnO thickness. In order to get the transmittance of the Gr/ZnO hybrid TCL higher than 80%, the appropriate combination of Gr/ZnO compound electrode should be a single layer of Gr with ZnO no thicker than 400 nm (1L Gr/400-nm ZnO), 2L Gr/300-nm ZnO, 3L Gr/200-nm ZnO, or 4L Gr/100-nm ZnO. The LEDs with hybrid TCLs consisting of 1L Gr/300-nm AZO, 2L Gr/300-nm GZO, and 2L Gr/300-nm IZO have good performance, among which the one with 1L Gr/300-nm GZO has the best thermal property. Typically, the temperature of LEDs with 1L Gr/300-nm GZO hybrid TCLs will drop by about 7 K compared with that of the LEDs with a TCL without ZnO film.

关键词: finite element methods, light-emitting diodes, graphene, ZnO

Abstract:

In order to reduce the Schottky barrier height and sheet resistance between graphene (Gr) and the p-GaN layers in GaN-based light-emitting diodes (LEDs), conductive transparent thin films with large work function are required to be inserted between Gr and p-GaN layers. In the present work, three kinds of transparent conductive oxide (TCO) zinc oxide (ZnO) films, Al-, Ga-, and In-doped ZnO (AZO, GZO, and IZO), are introduced as a bridge layer between Gr and p-GaN, respectively. The influence of different combinations of Gr/ZnO hybrid transparent conducting layers (TCLs) on the optical and thermal characteristics of the GaN-LED was investigated by the finite element method through COMSOL software. It is found that both the TCL transmittance and the surface temperature of the LED chip reduce with the increase in Gr and ZnO thickness. In order to get the transmittance of the Gr/ZnO hybrid TCL higher than 80%, the appropriate combination of Gr/ZnO compound electrode should be a single layer of Gr with ZnO no thicker than 400 nm (1L Gr/400-nm ZnO), 2L Gr/300-nm ZnO, 3L Gr/200-nm ZnO, or 4L Gr/100-nm ZnO. The LEDs with hybrid TCLs consisting of 1L Gr/300-nm AZO, 2L Gr/300-nm GZO, and 2L Gr/300-nm IZO have good performance, among which the one with 1L Gr/300-nm GZO has the best thermal property. Typically, the temperature of LEDs with 1L Gr/300-nm GZO hybrid TCLs will drop by about 7 K compared with that of the LEDs with a TCL without ZnO film.

Key words: finite element methods, light-emitting diodes, graphene, ZnO

中图分类号:  (Analytical and numerical techniques)

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42.25.Dd (Wave propagation in random media)