极化调控GaN基三元合金能带和掺杂效应的研究

项目名称： 极化调控GaN基三元合金能带和掺杂效应的研究

项目编号： No.61306008

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 张连

作者单位： 中国科学院半导体研究所

项目金额： 25万元

中文摘要： GaN基光电器件性能的继续提高依赖于晶体质量、结构设计、极化效应以及p型掺杂等各方面的不断优化，借助III族氮化物中的极化电场所产生的高浓度感应电荷进行极化掺杂，同时利用极化电场进行能带调控，将有利于改善p型掺杂中高受主电离能所导致的低p型电导问题和强极化电场所致的空间电荷分离问题，从而进一步促进器件的发光效率。本项目拟通过理论能带模拟计算和金属有机物化学气相沉积等方法，探索极化调控的p型GaN基三元合金的空穴形成机理及散射机制；分析材料的电学性能与极化效应的变化规律以及极化电场对能带的作用机制；在此基础上发展出性能稳定的高p型电导高质量III族氮化物极化掺杂方法，获得能带和掺杂均极化调控的GaN基三元合金；采用极化调控的组分渐变AlGaN提高空穴注入效率，并采用组分渐变InGaN量子阱的极化电场调控能带，改善空间电荷分离现象，获得高效率低droop的GaN基发光二极管。

中文关键词： GaN基材料；金属有机化合物沉积；极化掺杂；发光二极管；

英文摘要： The further improvement of the performance of GaN based optoelectronic devices depends on optimization of the crystal quality, structure design, polarization effect and p-type doping and so on. Polarization-doping provides an attractive solution to p-type doping problem by ionizing acceptor dopants using the built-in electronic polarization. Further, the polarization electric field can modify the energy band of GaN based ternary alloys, which is expected to improve band bending, consequently enhancing the wave function overlap of the hole and electron . Based on our previous work of the polarization effect of III-V nitride semiconductors, we will use the polarization field to modify the energy band and doping effect of GaN based ternary alloy by using the metal organic chemical vapor deposition method and theoretical calculation in this research. We will investigate the formation mechanism and the scatter mechanism of holes in polarization-controled GaN based ternary alloys; analyse the relationship between the electrical properties and the polarization effect of the materials, study the mechanism of polarization electric field on the band. Then the polarization-modified energy band and doping effect of GaN based ternary alloys with high crystal quality and good performance will be achieved. Based on the above r

英文关键词： GaN；MOCVD；polarization-doping；；