Status of Performance and Reliability of 265 nm Commercial UV-C LEDs in 2023

In the last years, the research on ultraviolet-C (UV-C) light emitting diodes (LEDs) focused its efforts on the solution of major problems that limited the emitted optical power (OP) and that caused the sudden failure of the devices. This led to the availability in the market of some devices with interesting electro-optical characteristics and promising lifetimes. In this article, we decided to study the reliability of four commercial UV-C LEDs with a nominal wavelength of 265 nm, in order to study their lifetime and their possible implementation in disinfection systems. We submitted the devices to an accelerated lifetime test of 20000 min, at the absolute maximum current indicated in their respective datasheets. During the tests, we carried out electrical and optical measurements, and we evaluated their spectral characteristics before and after aging. Once identified the best sample, we compared it with the best sample at 275 nm studied in our previous work, in order to show all the problems to consider if these LEDs have to be used in machinery that will be placed on the market.