Light extraction efficiency enhancement of flip-chip blue light-emitting diodes by anodic aluminum oxide

Yi-Ru Huang; Yao-Ching Chiu; Kuan-Chieh Huang; Shao-Ying Ting; Po-Jui Chiang; Chih-Ming Lai; Chun-Ping Jen; Snow H Tseng; Hsiang-Chen Wang

doi:10.3762/bjnano.9.152

Light extraction efficiency enhancement of flip-chip blue light-emitting diodes by anodic aluminum oxide

Beilstein J Nanotechnol. 2018 May 30:9:1602-1612. doi: 10.3762/bjnano.9.152. eCollection 2018.

Authors

Yi-Ru Huang¹, Yao-Ching Chiu², Kuan-Chieh Huang³, Shao-Ying Ting³, Po-Jui Chiang⁴, Chih-Ming Lai⁵, Chun-Ping Jen⁶, Snow H Tseng¹, Hsiang-Chen Wang²

Affiliations

¹ Graduate Institute of Photonics and Optoelectronics, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan.
² Graduate Institute of Opto-Mechatronics, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chia-Yi 62102, Taiwan.
³ R&D Center, Genesis Photonics Inc., No.5, Dali 3rd Rd., Shanhua Dist., Tainan City 74144, Taiwan.
⁴ Department of Electronic Engineering, National Kaohsiung University of Applied Sciences, No.415, Jiangong Rd., Sanmin Dist., Kaohsiung City 80778, Taiwan.
⁵ Department of Electronic Engineering, Ming Chuan University, Taoyuan 333, Taiwan.
⁶ Department of Mechanical Engineering, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chia-Yi 62102, Taiwan.

Abstract

We produced an anodic aluminum oxide (AAO) structure with periodic nanopores on the surface of flip-chip blue light-emitting diodes (FC-BLEDs). The nanopores had diameters ranging from 73 to 85 nm and were separated by distances ranging from approximately 10 to 15 nm. The light extraction efficiency enhancement of the FC-BLEDs subjected to different durations of the second pore-widening process was approximately 1.6-2.9%. The efficiency enhancement may be attributed to the following mechanism: periodic nanopores on the surface of FC-BLEDs reduce the critical angle of total reflection and effective energy transfer from a light emitter into a surface plasmon mode produced by AAO.

Keywords: anodic aluminum oxide; critical angle of total reflection; efficiency enhancement; flip-chip blue light-emitting diode.