纳米图形化结构高效氮化镓发光器件的机理及光电特性研究

项目名称： 纳米图形化结构高效氮化镓发光器件的机理及光电特性研究

项目编号： No.61274008

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 无线电电子学、电信技术

项目作者： 陈宇

作者单位： 中国科学院半导体研究所

项目金额： 86万元

中文摘要： 围绕图形化结构在高效功率型发光器件中的制备方法，深入研究其对材料外延生长、光提取效率相关基础物理机理，以及图形化制备技术等问题，具有重要的科学意义和应用价值。针对纳米图形化对提高LED的内量子效率和提取效率的影响，主要研究纳米外延成核、生长、应力释放机制对材料晶体质量的机理，特别是亚波长散射效应降低内全反射、图形化引起位错的弯曲、应力降低对LED器件droop效应的影响等核心问题，掌握在图形化结构中光的传播、控制和束缚的物理机制，探索出光子在图形化结构和介质界面的传播规律，并结合自组装技术，设计出基于纳米图形衬底的高效发光外延结构。最终提高发光效率，制备出纳米图形化的LED器件，开发出若干具有自主知识产权的光电器件的关键技术。

中文关键词： 大功率LED；氮化镓；图形结构；发光效率；

英文摘要： GaN and its related compounds such as AlGaN and InGaN have emerged as important semiconductor materials for high-performance light emitters in the ultraviolet (UV), blue, and green spectral regions. However, one still needs to further improve output efficiency of these GaN-based light-emitting diodes (LEDs) for applications such as solid-state lighting. Therefore, based on the fabrication methods of patterned sapphire substrate (PSS), further research of basal physical mechanism with respect to GaN epitaxial growth and light extraction efficiency shows great importance. In this project, in view of the influence of nano-pattern on the enhancement of internal quantum efficiency (IQE) and light extraction efficiency (LEE), our research is focused on the improvement of crystalline quality by nano-epitaxy. This is concerned with the nano-size nuclear layer, strain relaxation and threading dislocation bending due to PSS substrate. The droop effect of LED at high current density may be reduced due to the decrease of the stress during the nano-epitaxy. Additionally, sub-wavelength scattering effect on nano-PSS may obviously reduce the internal reflection and enhance the light extraction efficiency. Furthermore, we aim to understand the physical mechanism of light transporting, regulating and confining in the pattern epi

英文关键词： light-emitting-diode；GaN；patterned sapphire substrate；luminous efficiency；