Efficiency improvement analysis of nano-patterned sapphire substrates and semi-transparent superlattice contact layer in UVC light-emitting diodes

被引：14

作者：

Huang, Chia-Yen ^{[1
]}

Tsai, Chia-Lung ^{[1
]}

Huang, Cheng-Yao ^{[2
]}

Yang, Rong-Yu ^{[3
]}

Wu, YewChung Sermon ^{[4
]}

Yen, Hung-Wei ^{[2
]}

Fu, Yi-Keng ^{[1
]}

机构：

[1] Ind Technol Res Inst, Elect & Optoelect Syst Res Labs, 195,Sec 4,Chung Hsing Rd, Hsinchu, Taiwan

[2] Natl Taiwan Univ, Dept Mat Sci & Engn, 1,Sec 4,Roosevelt Rd, Taipei, Taiwan

[3] Natl Chung Hsing Univ, Dept Mat Sci & Engn, 145 Xingda Rd, Taichung, Taiwan

[4] Natl Chiao Tung Univ, Dept Mat Sci & Engn, 1001 Ta Hsueh Rd, Hsinchu, Taiwan

来源：

APPLIED PHYSICS LETTERS | 2020年 / 117卷 / 26期

关键词：

ALN; QUALITY; POWER;

D O I：

10.1063/5.0037588

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

UVC light-emitting diodes (LEDs, lambda =275nm) with different types of contact layers and sapphire substrates were demonstrated on high-quality AlN templates. For LEDs on flat sapphire substrates (FSSs), replacing the absorbing p-GaN contact with p-AlGaN short-period superlattices (p-SPSLs) strongly enhanced the emission along the substrate normal. The integrated external quantum efficiency (EQE) increased from 2.4% to 3.9% under I=350mA. For LEDs with a p-SPSL contact, replacing the FSS with nano-patterned sapphire substrates slightly deteriorated the quality of epitaxy, but the overall EQE is still enhanced to 4.4% under I>350mA without lens encapsulation. According to the far-field intensity measurement, the light extraction is better improved along the high emission angle to the substrate normal. The interplay among substrates, dipole polarization, and EQE enhancement factors was further analyzed and discussed in the context.

引用

页数：6

共 36 条

[1] Reduction of threading dislocation densities in AlN/sapphire epilayers driven by growth mode modification [J].

Bai, J ;

Dudley, M ;

Sun, WH ;

Wang, HM ;

Khan, MA .

APPLIED PHYSICS LETTERS, 2006, 88 (05) :1-3

[2] Internal Quantum Efficiency of Whole-Composition-Range AlGaN Multiquantum Wells [J].

Ban, Kazuhito ;

Yamamoto, Jun-ichi ;

Takeda, Kenichiro ;

Ide, Kimiyasu ;

Iwaya, Motoaki ;

Takeuchi, Tetsuya ;

Kamiyama, Satoshi ;

Akasaki, Isamu ;

Amano, Hiroshi .

APPLIED PHYSICS EXPRESS, 2011, 4 (05)

[3] High internal quantum efficiency in AlGaN multiple quantum wells grown on bulk AlN substrates [J].

Bryan, Zachary ;

Bryan, Isaac ;

Xie, Jinqiao ;

Mita, Seiji ;

Sitar, Zlatko ;

Collazo, Ramon .

APPLIED PHYSICS LETTERS, 2015, 106 (14)

[4] Modeling and optimization of p-AlGaN super lattice structure as the p-contact and transparent layer in AlGaN UVLEDs [J].

Chen, Xinhui ;

Ho, Kuan-Ying ;

Wu, Yuh-Renn .

OPTICS EXPRESS, 2015, 23 (25) :32367-32376

[5] Angular distribution of polarized light and its effect on light extraction efficiency in AlGaN deep-ultraviolet light-emitting diodes [J].

Chen, Xinjuan ;

Ji, Cheng ;

Xiang, Yong ;

Kang, Xiangning ;

Shen, Bo ;

Yu, Tongjun .

OPTICS EXPRESS, 2016, 24 (10) :A935-A942

[6] Sandwich method to grow high quality AlN by MOCVD [J].

Demir, I. ;

Li, H. ;

Robin, Y. ;

McClintock, R. ;

Elagoz, S. ;

Razeghi, M. .

JOURNAL OF PHYSICS D-APPLIED PHYSICS, 2018, 51 (08)

[7] 282-nm AlGaN-based deep ultraviolet light-emitting diodes with improved performance on nano-patterned sapphire substrates [J].

Dong, Peng ;

Yan, Jianchang ;

Wang, Junxi ;

Zhang, Yun ;

Geng, Chong ;

Wei, Tongbo ;

Cong, Peipei ;

Zhang, Yiyun ;

Zeng, Jianping ;

Tian, Yingdong ;

Sun, Lili ;

Yan, Qingfeng ;

Li, Jinmin ;

Fan, Shunfei ;

Qin, Zhixin .

APPLIED PHYSICS LETTERS, 2013, 102 (24)

[8] AlN nanostructures and flat, void-less AlN templates formed by hydride vapor phase epitaxy on patterned sapphire substrates [J].

Fujikura, Hajime ;

Konno, Taichiro ;

Kimura, Takeshi ;

Miyake, Hideto .

APPLIED PHYSICS EXPRESS, 2020, 13 (02)

[9] Improving AlN Crystal Quality and Strain Management on Nanopatterned Sapphire Substrates by High-Temperature Annealing for UVC Light-Emitting Diodes [J].

Hagedorn, Sylvia ;

Walde, Sebastian ;

Susilo, Norman ;

Netzel, Carsten ;

Tillner, Nadine ;

Unger, Ralph-Stephan ;

Manley, Phillip ;

Ziffer, Eviathar ;

Wernicke, Tim ;

Becker, Christiane ;

Lugauer, Hans-Juergen ;

Kneissl, Michael ;

Weyers, Markus .

PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE, 2020, 217 (07)

[10] 231-261 nm AlGaN deep-ultraviolet light-emitting diodes fabricated on AlN multilayer buffers grown by ammonia pulse-flow method on sapphire [J].

Hirayama, Hideki ;

Yatabe, Tohru ;

Noguchi, Norimichi ;

Ohashi, Tomoaki ;

Kamata, Norihiko .

APPLIED PHYSICS LETTERS, 2007, 91 (07)

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