AlGaN-based deep ultraviolet micro-LED emitting at 275 nm

• DOI: 10.1364/ol.431933
• Publication Date: 2021-06-16T13:00:09Z
• Authors: Huabin Yu; Muhammad Hunain M...; Danhao Wang; Zhongjie Ren; Haochen Zhang; Chen Huang; Meng Tian; Haiding Sun; Shibing Long
• Keywords: 0103 physical sciences; 01 natural sciences

The investigation of electrical and optical properties micro-scale AlGaN deep ultraviolet (DUV) light-emitting diodes (LEDs) emitting at <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:mn>275</mml:mn> <mml:mspace width="thickmathspace" /> <mml:mi mathvariant="normal">n</mml:mi> mathvariant="normal">m</mml:mi> </mml:math> was carried out, with an emphasis on fabricated devices having a diameter 300, 200, 100, 50, 20 µm, respectively. It revealed that the LED chips smaller mesa areas deliver considerably higher light output power density; meanwhile, they can sustain current density, which is mainly attributed to enhanced spreading uniformity in chips. Importantly, when decreases from 300 µm peak external quantum efficiency (EQE) increases by 20%, EQE density be boosted <mml:mn>8.85</mml:mn> <mml:msup> mathvariant="normal">A</mml:mi> <mml:mo>/</mml:mo> mathvariant="normal">c</mml:mi> <mml:mn>2</mml:mn> </mml:msup> <mml:mn>99.52</mml:mn> . Moreover, we observed longer wavelength emission enlarged full-width half-maximum (FWHM) LEDs chip sizes because self-heating effect high injection. These experimental observations provide insights into design fabrication high-efficiency micro-LEDs DUV regime different device geometries for various future applications.