Although deep ultraviolet (UV) light with a wavelength of 265 to 280 nm has a high virus inactivation effect, there are concerns about its effect on the human body. UV light with a wavelength of 220 to 230 nm (far-UV C (UVC) light) is considered to be harmless to the human body, but it has not been put into practical use because its luminous efficiency is extremely inferior to that of light with a wavelength of 265 to 280 nm. In this research, we developed a 230 nm far-UVC light-emitting diode (LED) through joint research with RIKEN. In the fabricated 230 nm far-UVC LED, a single chip achieved a maximum light output power of 2.7 mW in pulse operation, a maximum light output power of 1.1 mW in continuous operation, and a maximum external quantum efficiency of 0.25%. We also created a panel equipped with 25 LEDs and confirmed that there were no problems with its operation.

5.Development_of_230nm_Wavelength_Far_Ultraviolet_C_Light-Emitting_diodes.pdf