Japan's deep ultraviolet light emitting diode output power record

The Japan Institute of Physical Chemistry and the Agency for the Promotion of Science and Technology announced that a deep-ultraviolet light emitting diode (LED) with a wavelength of 250 nanometers developed by one of their research teams has successfully achieved a high output power of 15 milliwatts for the first time in the world, and its electron injection efficiency has improved. 80%. This deep ultraviolet light emitting diode is 7 times higher than the current highest output of the same type of equipment, and has a good bactericidal effect, and it can rapidly decompose the harmful substances such as BC and HL. It has reached a practical level. The research results have been applied for a patent on February 24, and the paper is scheduled to be published on the "Applied Physics Letters" published on March 25.

High power deep UV LEDs with wavelengths between 220 nm and 350 nm in sterilizing, water purification, medical, high-density light recording, high color rendering LEDled/'target='_blank'> lighting and high-speed decomposition of hazardous substances, etc. There are wide applications in the field. Until now, ultraviolet lasers and gas lamps using deep laser light sources such as excimer lasers and various frequency doubler lasers have been the mainstream. However, they have the disadvantages of large size, short life, and high cost, and are difficult to use. The use of high-brightness deep-ultraviolet LEDs and deep-ultraviolet LDs for semiconductors can achieve miniaturization and provide inexpensive, efficient, and long-life UV light sources with a broader application perspective.

The aluminum nitride gallium material is considered to be the most ideal deep ultraviolet luminescent material, and the research team achieved the highest in the world by reducing the dislocation density of the aluminum gallium nitride buffer layer and inserting a multi-quantum barrier as an electron block layer in the upper part of the quantum well luminescent layer. Power output. The results of this research have broken the understanding that deep ultraviolet LEDs cannot achieve high efficiency in the past, and have succeeded in bringing the UV output power to a practical level. At the same time, multi-quantum barriers may not only improve the efficiency of the ultraviolet light emitting devices but also the already practical blue LEDs, green LDs, and LED and white LED lamps.

In terms of sterilization, the highest efficiency of direct UV disinfection is in the wavelength range from 250 nm to 280 nm, and in the decomposition of organic matter, dust, and hardly decomposable pollutants such as Erlenmeyer, ultraviolet radiation with a wavelength of 270 nm to 320 nm is used. The ultraviolet irradiation system of photocatalysts such as titanium oxide has a relatively good decomposition effect. The research team plans to further increase the efficiency of deep ultraviolet sterilization for wavelengths from 250 nm to 280 nm, and to achieve efficient wavelengths at wavelengths from 220 nm to 390 nm, and to conduct in-depth research on the deep-ultraviolet high-power output to achieve the current 1.5 The efficiency of % increases to ten digits.