含有反相畴的3D紫外LED界面调控及发光性能研究

具有大比表面积的纳米阵列结构有助于提升紫外LED的光子提取效率，近年来受到广泛关注。传统等离子体刻蚀方法得到的纳米阵列紫外LED容易因为等离子轰击而产生较高的缺陷态密度，引起载流子非辐射复合加剧而降低出光效率。针对这一不足，本项目拟在图形化AlN缓冲层上外延生长含有反相畴的氮化物薄膜，同时可控湿法刻蚀制备出具有低界面态密度的3D纳米阵列结构的紫外LED。本项目将分析亚微米尺度下反相畴的形成机制和分布规律，探索反相畴对器件内部载流子传输与复合的作用原理，对比湿法刻蚀和等离子体刻蚀制备的3D纳米阵列的发光性能，深入理解缺陷态密度对于紫外LED辐射复合效率的影响机制。本项目的成功实施有望为下一代紫外LED的效率提升提供一种新的思路和实验支撑。

Nanostructure-array used in light extraction enhancement of UV-LEDs has drawn wide attentions due to its large aspect ratio. Traditional nanostructure array UV-LEDs fabricated by plasma etching suffers from high density surface trap centers as a result of plasma damage, leading to non-radiative recombination of carriers. In order to overcome this problem, UV-LEDs with inversion domain boundaries (IDB) will be fabricated based on polarity control of III-nitride materials, followed by wet chemical etching to achieve 3D nanostructures with low surface defects. We will first explore the formation mechanism and distribution condition of IDBs within sub-micrometer scale; Secondly, we will investigate the influence of IDB on the carrier transport and recombination inside UV-LEDs; Furthermore, we will explore the influence of 3D structure defect states on LED radiative recombination efficiency and comparing our 3D UV-LEDs with traditional plasma etched nanostructure UV-LEDs. The successful implantation of this project is important in providing new ideas and strong experimental support to the development of next generation high efficiency UV-LEDs.