GaN基发光二极管外延中p型AlGaN电子阻挡层的优化生长  

Optimized growth of p-type AlGaN electron blocking layer in the GaN-based LED

作　　者：王兵[1] 李志聪[1] 姚然[1] 梁萌[1] 闫发旺[1] 王国宏[1] 

机构地区：[1]中国科学院半导体研究所半导体照明研发中心,北京100083

出　　处：《物理学报》2011年第1期473-478,共6页Acta Physica Sinica

基　　金：国家高技术研究发展计划(批准号:2006AA03A114)资助的课题~~

摘　　要：本文利用金属有机物化学气相沉积(MOCVD)方法系统地研究了p-AlGaN层掺杂机理及优化设计生长.明确了生长温度、压力及TMAl的流量对AlGaN层Al组分的影响关系,并给出了各自不同的机理与作用.研究发现,Al组分介于10%—30%之间能够很好地将电子限定在量子阱区域并保持高的材料晶体质量.发展了一种新的生长技术来克服p-AlGaN层掺入效率低下和空穴注入不足的问题.优化条件下生长的p型AlGaN电子阻挡层很大地提升了InGaN/GaN基LED的输出光功率.In the High-power InGaN /GaN-based LED structures,p-AlGaN layer plays a role as electron blocking layer. In this paper,GaN /InGaN-based LED have been grown on sapphire by metal organic chemical vapor deposition （MOCVD）,and the p-type doping mechanism and structural optimization of AlGaN layer were studied. The ways to change AlGaN components have been discussed. We found that the growth temperature,growth pressure and flow TMAl （ mole ratio） have strong effect on the Al components through different mechanisms. In the AlGaN electron blocking layer,the Al composition is between 10% —30% and the electron could be well limited to the quantum well region,maintaining a high quality crystal material. The p-type doping efficiency of AlGaN layer is low,and there is a magnesium droop problem due to lack of hole injection. A new growth method is suggestece to solve the problem. Grown under optimal conditions,the p-type AlGaN inserted in a LED structure greatly improves the output optical power of LED device.

关 键 词：氮化镓基 LED AL组分 电子阻挡层 

分 类 号：O471[理学—半导体物理]