Enhanced light extraction efficiency of micropixel geometry AlGaN DUV light-emitting diodes. (15th July 2021)

• Record Type: Journal Article
• Authors: Floyd, Richard; Gaevski, Mikhail; Hussain, Kamal; Mamun, Abdullah; Chandrashekhar, MVS; Simin, Grigory; Khan, Asif
• Is Part Of: Applied physics express. Volume 14:Number 8(2021)
• Publication Date: 2021-07-15
• Subjects: DUV LED -- UVC LED -- AlGaN micropixel -- light extraction efficiency -- light output power -- micro-LED; Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.35848/1882-0786/ac0fb8
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: We report a 1.8 times improved light extraction efficiency for truncated cone AlGaN DUV (275 nm emission) micropixel LEDs when the pixel size was reduced from 90 to 5 μ m. This is a direct consequence of reducing the re-absorption of sideways-travelling photons, as the lateral absorption length was measured to be 15 μ m using cathodoluminescence. We also investigated the effect of an Al2 O3 /Al sidewall coating on the device performance which led to an on-wafer pulsed-mode brightness of 10.3 kW cm −2 from a single 5 μ m truncated cone micropixel.