Among the ultraviolet rays, light with a wavelength between 200 nanometers and 350 nanometers is called deep ultraviolet, which is widely used in air sterilization and formaldehyde treatment in water purification plants, hospitals, and factory clean rooms. In the past, many deep ultraviolet light sources used mercury lamps, but the "Minamata Convention" signed by the United Nations last year stipulated that the use of mercury should be greatly restricted, so it is necessary to develop alternative light sources.

　　Deep ultraviolet LEDs can be used as light sources to replace mercury ultraviolet fluorescent lamps, but in the past, expensive sapphire substrates were used to make deep ultraviolet LED light sources, and its high cost limited its popularity. A senior researcher at Ritsumeikan University Kexin Aoyagi and others reported that cheap silicone can be used as a substrate instead of sapphire, which can greatly reduce costs.

　　 In addition, in the past process, in order to allow current to pass, it is necessary to peel off a part of the insulating layer on the substrate. The new method is to attach a layer of aluminum nitride to the silicone substrate as an insulator, and then open a number of micro-holes to allow current to pass. In this way, there is no need to peel off the insulating layer, which greatly shortens the process. The previous 5 days of production work can be shortened to 1 day, and the damage to the LED when the insulating layer is peeled off is avoided, and the luminous efficiency is also improved.