Influence of crystal quality of underlying GaN buffer on the formation and optical properties of InGaN/GaN quantum dots
Influence of crystal quality of underlying GaN buffer on the formation and optical properties of InGaN/GaN quantum dots
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DOI：
10.1063/1.3224897
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发表时间：
2009-09-07
影响因子：
4
通讯作者：
Wang, T.
中科院分区：
文献类型：
--
作者：
Davies, S. C.;Mowbray, D. J.;Wang, T.
报道了在两种不同的GaN模板上生长InGaN量子点（QD）的研究-使用传统两步法生长GaN和使用我们最近开发的高温（HT）AlN作为缓冲层生长。HT AlN缓冲层导致随后沉积的GaN中的位错密度，特别是螺旋位错的显著降低。这种减少通过（0002）X射线衍射摇摆曲线宽度的显著减小来证实。HT AlN缓冲层上的GaN导致InGaN QD的高密度（10（10）/cm（2）），而相比之下，使用两步方法生长的常规GaN层上的InGaN QD具有小得多的密度（类似于10（8）/cm（2））。此外，已发现GaN/HT AlN上的量子点的载流子寿命比常规GaN上的量子点的载流子寿命长9倍。
A study of InGaN quantum dots (QDs) grown on two different GaN templates-GaN growth using a conventional two-step approach and growth using our recently developed high temperature (HT) AlN as a buffer-is reported. The HT AlN buffer leads to a significant reduction in the dislocation density, particularly screw dislocations, in subsequently deposited GaN. This reduction is confirmed by a significant decrease in the (0002) x-ray diffraction rocking curve width. The GaN on the HT AlN buffer leads to a high density (10(10)/cm(2)) of InGaN QDs, whereas in contrast InGaN QDs on the conventional GaN layer grown using the two-step approach have a much smaller density (similar to 10(8)/cm(2)). Furthermore, the carrier lifetimes for the QDs on the GaN/HT AlN have been found to be up to nine times longer than those for the QDs on the conventional GaN.