Sim, Kee-Baek Jin, Jun-Young Kim, Su-Kyung Ko, Young-Jin Hwang, Gyu Weon Seong, Tae-Yeon Amano, Hiroshi 2024-01-19T11:34:13Z 2024-01-19T11:34:13Z 2022-06-02 2022-07 0925-8388 https://pubs.kist.re.kr/handle/201004/114920 In this study, chlorine (Cl) treatment was carried out on p-AlGaN to enhance the performance of ultraviolet C light emitting diodes (UVC LEDs) by modifying ITO work function and hence reducing the contact resistance of ITO/Al reflector. The Cl-treated UVC LEDs exhibit the forward voltage of 6.88 V at 20 mA, whereas the reference samples show 7.50 V. The light output power and relative wall plug efficiency (WPE) of the Cl-treated UVC LEDs are enhanced by 17.1% at 500 mW and 19.5% at 100 mA, respectively, as compared to the reference. Additionally, the Cl-treated LEDs also display reduction in both the leakage current and ideality factor. Further, the photoluminescence (PL) intensity of AlGaN micro-disks is also enhanced by the Cl-treatment. X-ray photoemission spectroscopy (XPS) results indicate the formation of Cl-ITO at the ITO/p-AlGaN interface and the passivation of the surface states of AlGaN by Cl radicals. Based on the XPS results, a possible mechanism for the improved performance of Cl-treated UVC AlGaN-based LEDs is described and discussed. (c) 2022 Elsevier B.V. All rights reserved. English Elsevier BV Improved performance of deep ultraviolet AlGaN-based light-emitting diode by reducing contact resistance of Al-based reflector Article 10.1016/j.jallcom.2022.164895 1 Journal of Alloys and Compounds, v.910 Journal of Alloys and Compounds 910 N scie scopus 000797918000005 Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metallurgy & Metallurgical Engineering Article INDIUM TIN OXIDE UV-LEDS H3PO4 TREATMENT ENHANCEMENT PASSIVATION UVC LEDs Chlorine treatment ITO Work function Surface passivation UVC LEDs Chlorine treatment ITO Work function Surface passivation