Self-Monitoring High-Reliability 254 nm AlGaN Integrated Module for Ultraviolet Bacterial Inactivation

Conventional 254 nm mercury lamps suffer from critical limitations including environmental contamination and short operational lifetime. To replace them, this study focuses on the development of 254 nm AlGaN light emitting diode (LED) with internal quantum efficiency of 84.0%, and proposes a LED and photodetector (PD) integrated device capable of real-time light out power (LOP) monitoring. The optimized integrated devices demonstrate remarkable performance: a photo-to-dark current ratio exceeding 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> at zero bias voltage, and the responsivity, specific detectivity and external quantum efficiency of self-driven PDs are 5.44 A/W, 1.72×10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sup> Jones and 2659%, respectively. Furthermore, we have packaged a high-power 4×4 LED-PD array module and established a quantitative model correlating the LED LOP with the PD photocurrent. The module demonstrates superior germicidal efficacy, achieving 99.9% inactivation of Staphylococcus aureus within 1 second of irradiation. This integrated architecture with inherent self-monitoring capability enhances the operational reliability of high-power DUV devices, thereby advancing their practical applications in advanced disinfection systems.