International Conference of Physicists.SPb, October 20-24, 2025, Saint Petersburg

Reduction of external quantum efficiency of ultraviolet LEDs caused by overdoping of barriers with silicon

E. I. Shabunina^a, N. M. Shmidt^a, A. E. Chernyakov^b, N. A. Talnishnikh^b, A. L. Zakhgeim^b, A. E. Ivanov^bc, L. A. Aleksanyan^d, A. Ya. Polyakov<sup>d

a</sup> Ioffe Institute, St. Petersburg
^b Submicron Heterostructures for Microelectronics Research and Engineering Center, Russian Academy of Sciences, St. Petersburg
^c Saint Petersburg Electrotechnical University "LETI"
^d National University of Science and Technology «MISIS», Moscow

Abstract: Commercial AlGaN ultraviolet LEDs with emission wavelength of 270–280 nm and external quantum efficiency of 5.7% were studied. $C$–$V$ profiling revealed an order of magnitude higher electron concentration in the active region compared to blue LEDs, caused by overdoping with silicon. Analysis of electroluminescence spectra and frequency dependences of the spectral density of low-frequency noise revealed the rearrangement of excited defects in ultraviolet LEDs at injection levels an order of magnitude lower than in blue LEDs, as well as the onset of defect generation during aging after 25 h.

Received: 05.05.2025
Revised: 24.06.2025
Accepted: 18.09.2025

DOI: 10.61011/FTP.2025.07.62003.8101