Deep Ultraviolet Light Emitting Diode Based on Aluminum Gallium Nitride

Abstract

AlGaN-based deep ultraviolet LED has gradually attracted people's attention, because it can be used in sterilization, secret communication and other fields. According to the research report of nearly twenty years, there are still many shortcomings in the external quantum efficiency, internal quantum efficiency and light extraction efficiency of AlGaN-based deep ultraviolet LED. For this reason, researchers have made many efforts at the chip level, including epitaxial and doping technology. In recent years, more and more researchers have studied packaging technology with low light efficiency caused by Fresnel and total reflection. In epitaxial technology, this paper mainly introduces the material selection of substrate and the use of buffer layer. In this paper, the most commonly used substrate selection and the existing problems and solutions of substrates are summarized. The current process of buffer layer is also introduced. On the doping level, the present situation and development of N-type doping and P-type doping are introduced respectively. The use of the latest doping elements is introduced in this paper. Packaging technology explains the choice between organic materials and inorganic materials, and how the packaging structure can avoid the reflection loss of light to the maximum extent. Finally, the article predicts the future development direction.