摘要
文章研究了MOCVD系统中影响A lN生长速率的机制。我们通过在位监控曲线控制生长过程,改变了不同的生长条件,得到了A lN生长速率与生长温度、反应室压力、NH3流量、TMA l流量等生长参数的关系。实验发现,A lN生长速率与生长温度、反应室压力、NH3流量等参数之间表现出反常的依赖关系。我们认为,MOCVD系统中存在A l原子的寄生反应,导致了反常现象的发生。A lN生长速率与TMA l流量的关系进一步证明了这一点。实验结果表明,较低的生长温度、较小的反应室压力能够有效地提高A lN生长速率,同时也将有利于提高A l-GaN材料中的A l组分。
The Al composition of MOCVD-grown AIGaN alloy layers is found to be greatly influenced by the parasitic reaction between NH3 and TMAl. The growth process of AlN is carefully investigated by monitoring the in situ optical reflection. The abnormal dependencies of growth rate on growth temperature, reactor pressure, and flux of NH3 are observed,and can be well explained by the effect of parasitic reaction. The increase of growth rate with increasing flux of TMAl is found to depend on the growth temperature and reactor pressure due to the presence of parasitic effect. A relatively low growth temperature and a reduced reactor pressure are suggested for the effective decrease of parasitic reaction during the MOCVD growth of AlN and a more effective incorporation of Al into the AlGaN layers. N ; parasitic reaction
出处
《激光与红外》
CAS
CSCD
北大核心
2005年第11期877-879,共3页
Laser & Infrared
