Cracking the Si Shell Growth in Hexagonal GaP-Si Core-Shell Nanowires
Cracking the Si Shell Growth in Hexagonal GaP-Si Core-Shell Nanowires
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DOI：
10.1021/nl504813e
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发表时间：
2015-05-01
期刊：
影响因子：
10.8
通讯作者：
Fontcuberta i Morral, A.
中科院分区：
文献类型：
--
作者：
Conesa-Boj, S.;Hauge, H. I. T.;Fontcuberta i Morral, A.
半导体纳米线由于其更有效的应变弛豫而增加了可能的异质结构的调色板。其中，核壳异质结构比轴向异质结构对应变敏感得多。现在普遍认为，失配位错的形成取决于晶格失配和核壳的相对尺寸。在这里，我们首次展示了核壳纳米线中存在的一种新的缺陷：裂纹。这些缺陷并不源于晶格失配，（我们证明他们的外观在一个基本上为零失配系统），但从生长过程中的纳米线的热历史。裂纹缺陷导致二次缺陷的发展，如I-1型，层错和弗兰克型位错。这些结果提供了关键的信息，具有重要意义的优化合成的铱基核-壳异质结构。
Semiconductor nanowires have increased the palette of possible heterostructures thanks to their more effective strain relaxation. Among these core shell heterostructures are much more sensitive to strain than axial Ones. It is now accepted that the formation of misfit dislocations depends both oh the lattice mismatch and relative dimensions of the core and the shell. Here, we show for the first time the existence of a new kind of defect in core shell nanowires: cracks. These defects do not originate from a lattice mismatch,(we demonstrate their appearance in an essentially zero-mismatch system) but from the thermal history during the growth of the nanowires. Crack defects lead to the development of secondary defects, such as type-I-1, stacking faults and Frank-type dislocations. These results provide crucial information with important implications for the optimized synthesis of nanowire-based core-shell heterostructures.