Far-UVC emission of polarity-engineered AlGaN MQW using carbon nanotube-based cold cathode electron beam

• Published in: Applied physics letters Vol. 122; no. 9
• Main Authors: Choi, Uiho, Yoo, Sung Tae, Kim, Minho, So, Byeongchan, Cheon, Changheon, Yang, Mino, Lee, Moonsang, Park, Kyu Chang, Nam, Okhyun
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 27-02-2023
• Subjects: Applied physics; Carbon nanotubes; Cold cathodes; Electrode polarization; Electromagnetic absorption; Electron beams; Emitters; Emitters (electron); Energy conversion efficiency; Epitaxial growth; Light emission; Light emitting diodes; Low conductivity; Maximum power
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/5.0122697

Far-ultraviolet-C (UVC) light is an efficient and safe germicide because the wavelength band eradicates viruses but is harmless to human cells. In this study, electron-beam-pumped AlGaN emitters have been introduced as an alternative to far-UVC light emitting diodes which are limited by certain drawbacks, such as low conductivity and light absorption of the p-layer and side emission due to polarization at short wavelengths. We demonstrate a highly efficient far-UVC AlGaN emitter using a carbon nanotube-based cold cathode electron beam (C-beam). To maximize light emission, materials were grown via novel in situ lateral polarity engineering epitaxy. The C-beam enables the large-area emission of up to 528 mm2, and the maximum power conversion efficiency is 0.5% at 232 nm.