Enhanced light extraction of the deep-ultraviolet micro-LED via rational design of chip sidewall

• DOI: 10.1364/ol.441285
• Publication Date: 2021-09-08T12:30:49Z
• Authors: Meng Tian; Huabin Yu; Muhammad Hunain M...; Zhanyong Xing; Chen Huang; Hongfeng Jia; Haochen Zhang; Danhao Wang; Shi Fang; Haiding Sun
• Keywords: 02 engineering and technology; 0210 nano-technology

In this Letter, we perform a comprehensive investigation on the optical characterization of micro-sized deep-ultraviolet (DUV) LEDs (micro-LEDs) emitting below 280 nm, highlighting light extraction behavior in relation to design chip sidewall angle. We found that micro-LEDs with smaller inclined angle ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>∼</mml:mo> </mml:mrow> <mml:msup> <mml:mn>33</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> ) have improved external quantum efficiency (EQE) performance 19% more than larger <mml:mn>75</mml:mn> ). Most importantly, EQE improvement by adopting an can be outstanding as diameter LED reduces from 40 20 <mml:mi>μ</mml:mi> <mml:mi mathvariant="normal">m</mml:mi> . The enhanced angles attributed stronger reflection sidewall, leading (LEE). end, numerical modeling further reveals and verifies impact LEE micro-LEDs, corroborating our experiment results. This Letter provides fundamental understanding optimized geometry fabricate highly efficient DUV spectrum future.