Ultraviolet (UV) light usually are light waves with 100 to 280 nanometer (nm) wavelengths, according to a report by Chinese-language newspaper Science and Technology Daily. These lights are mostly used to kill germs, medically, and in biochemical tests. It also has high application value in storing highly classified messages and telecommunications. Compared to UV light sources from mercury lamps, AlGaN based UV LEDs have the advantages of being robust, energy-efficient, long lifetime, and is mercury free making them environmental friendly. These LED lights are gradually penetrating conventional mercury light application fields. At the same time, UV LEDs advantages have inspired many new consumer electronics to adopt these applications, for example in white household appliances disinfection modules, portable water purification systems, smartphone disinfection and others. It shows wide market applications, and after semiconductor LED lighting has become the next popular global LED R&D and investment field.
According to research reports, the future LED market might be split in two. One field uses visible light LED in general lighting, and the other uses innovative UV LED. Compared to visible light, UV LED has lower luminous efficacy and power output. For AlGaN to make breakthroughs in these two fields, the research focus should be on making technology advancements in low dislocation density material AIN and AlGaN material core, epitaxal and other mixed technologies to design LED components with high quantum efficiency and light extraction efficiency, said Zhang Yun, Researcher, Institute of Semiconductors, Chinese Academy of Sciences (CAS). The research can also help in developing highly reliable chip preparation technology and LED package technology.
The material quality and lighting extraction efficiency was improved by using nanotechnology to make patterned substrates, researchers pointed out in their research report published in Applied Physics Letter. A UV LED that emits a UV wavelength of 280 nm under 20 amp electric current can reach a light output of more than 3 mW. Its quantum efficiency and light output efficiency is nearly double that of traditional substrates. Through optimized package technology, it also enabled UV LED to reach more than 4 mW light output. In 2013, the CAS institute became the leader in China’s key UV LED material and component manufacturing.