AlGaN基深紫外LED面临严重的出光效率问题，成为限制其应用的瓶颈。AlGaN量子阱结构的光出射过程受到量子阱的发光偏振特性、光传播过程和光导出过程综合作用，是LED研究面临的新课题。本项目将系统开展AlGaN量子阱能带结构、紫外光与量子阱结构相互作用、光场分布的理论计算和实验研究，明确载流子跃迁的各向异性、光强空间分布的变化规律及内在关系，建立综合发光过程和传播过程的光出射效率和光场分布的分析方法，研究量子阱能带结构调制和传播过程调制方法，设计和制备具有出光增强结构的LED外延片和芯片，通过优化结构参数，显著提高器件的正面出光；研究外延层界面微纳结构、表面等离激元耦合对光出射过程的作用，探索新型有效的提高发光效率和出射效率的方法，为实现高性能的AlGaN基深紫外LED提供基础。

AlGaN based deep UV LEDs are promising in wide applications such as biological detection, medical treatment, air- and water-purification and short distance communication for military uses, and are attracting much attention of researches. However，the low light extraction efficiency usually less than 8%, becomes the key issue hindering the improvement and applications of DUV LEDs. .In this project, facing the new challenges in light extracting from AlGaN-based deep UV LEDs，we plan to begin with the understanding of the mechanisms of light extraction, which evolves carrier recombination transitions, light propagation in the layers and total reflection from the surface of chip. By utilizing the theoretical and experimental researches on the band structure of quantum wells, UV light absorption and reemission from quantum wells, and special distribution of light intensity, the changes the anisotropy transition rate and light intensity distribution as well as the their relations will be revealed. Furthermore, with a newly-built method for describing the synthesized effect light emitting and propagating on the light extraction efficiency and spatial intensity distribution, we will find out the way to modulate these processes and have more amount of light extracted from front surface of DUV LEDS after optimization. Also, a study on the controlling the changes of light extraction behaviors from LED surfaces with structures of micro scale and nano scale, probably also by the aid of expectable coupling effect of SPP from the nano structure of metal and quantum wells, will performed for exploring the new physical mechanism and new method thereafter. Through the above efforts, we will not only make comprehensive understanding on the physical mechanism influencing the light extraction performance of AlGaN-based DUV LEDs, and developing the corresponding control methods, which would provide scientific basis for further improvement of device performance.