title: Air-ring microstructure arrays for enhanced light extraction from a face-up light-emitting diode.
abstract: In this Letter, a light-emitting diode (LED) with prism-shaped-air-ring microstructures (PSAMs) formed on flat sapphire substrate is demonstrated as an alternative design to face-up LEDs on patterned sapphire substrate (PSS) for enhanced light extraction efficiency. In this LED design, the emitted photons can be deflected to the top of the chip for its effective extraction, contrary to the PSS-LED wherein photons are guided to sapphire and get absorbed by packaging materials. The PSAM-LED showed an enhancement in the radiometric power as high as 10% with a low far-field angle of 129° over that of a PSS-LED under an injection current of 20 mA.
authors: School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University, Jeonju, South Korea.
authors: Hyun Kyu
authors: HK
authors: Kim
authors: Young Jae
authors: YJ
authors: Park
authors: Ji Hye
authors: JH
authors: Kang
authors: Nam
authors: N
authors: Han
authors: Min
authors: M
authors: Han
authors: Beo Deul
authors: BD
authors: Ryu
authors: Kang Bok
authors: KB
authors: Ko
authors: Jong Han
authors: JH
authors: Yang
authors: Young Taek
authors: YT
authors: Kim
authors: S
authors: S
authors: Chandramohan
authors: Hyun
authors: H
authors: Jeong
authors: Mun Seok
authors: MS
authors: Jeong
authors: Chang-Hee
authors: CH
authors: Hong