半极性准同质外延绿光LED及量子效率提升技术研究

项目名称： 半极性准同质外延绿光LED及量子效率提升技术研究

项目编号： No.61274040

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： 魏同波

作者单位： 中国科学院半导体研究所

项目金额： 82万元

中文摘要： 红绿蓝三基色实现白光具有光谱范围宽、显色性高、色温可调等优点，是实现白光LED的理想技术路线，但目前绿光LED发光效率低下成为制约三基色白光LED发展和应用的瓶颈。本项目拟在HVPE技术制备的高质量半极性GaN复合衬底基础上，沿半极性方向准同质外延绿光LED实现降低极化电场和droop效应，进而提高绿光LED的效率。通过InAlGaN形核层和多层应力调制层技术研究准同质外延生长规律，揭示穿透位错、堆垛层错等缺陷的湮灭和控制机制；采用理论计算和实验相结合，优化有源区结构设计，掌握半极性InGaN多量子阱输运和复合物理过程，揭示半极性材料中辐射复合中心和非辐射复合中心角色的微观区域结构、和生长条件的关系及其形成机理，进而获取解决绿光大电流效率下降的关键因素；结合表面等离激元耦合和新型垂直封装技术，探索光出射增强物理机制，实现高光提取效率，最终研制出高效率InGaN基半极性绿光LED。

中文关键词： 氮化镓；半极性；发光二极管；纳米柱；表面等离激元

英文摘要： Light-emitting diodes (LEDs) have attracted considerable interest as candidates for next-generation lighting because they promise to reduce energy consumption enormously. Semiconductor-based white-light generation by combining the red, green, and blue light emitting diodes illustrates many merits as ideal technology route, such as the broad spectrum, high color rendering index and regulation of color temperature etc.. However, the peak internal quantum efficiency (IQE) of green LEDs is significantly lower than that of InGaN-based blue and AlGaInP-based red LEDs, which is characteristically called the "green gap". In this project, we plan to homoepitaxy the green LED along the semipolar orientation on the high quality GaN template obtained by hydride vapor phase epitaxy (HVPE) technology. By virtue of the obvious decrease of the polarization effect at high indium content, the quantum efficiency of green LED can be improved. The growth mechanism of quasi-homoepitaxy is investigated near the interface along the semipolar orientation. Using InAlGaN nuclear layer and multi-layer buffer for strain regulation, the residual stress in the quasi-homoepitaxial growth is obviously reduced. The annihilation mechanism of the threading dislocation (TDs) and basal-plane stacking faults (BSFs) is revealed by TEM and CL. With the

英文关键词： GaN；Semipolar；LED；Nanorod；Surface plasmon